10 Vạn câu hỏi vì sao

["V\u00ec sao c\u00f3 th\u1ec3 d\u1ef1 \u0111o\u00e1n th\u1eddi ti\u1ebft qua h\u00ecnh d\u1ea1ng M\u1eb7t tr\u0103ng? D\u00e2n gian Trung Qu\u1ed1c c\u00f3 kh\u00f4ng \u00edt c\u00e2u ng\u1ea1n ng\u1eef n\u00f3i v\u1ec1 th\u1eddi ti\u1ebft l\u00e0 d\u1ef1a v\u00e0o h\u00ecnh d\u1ea1ng M\u1eb7t tr\u0103ng \u0111\u1ec3 d\u1ef1 b\u00e1o s\u1ef1 thay \u0111\u1ed5i th\u1eddi ti\u1ebft. V\u00ed d\u1ee5 nh\u01b0 \u201ckh\u00f4ng s\u1ee3 m\u1ed3ng m\u1ed9t \u00e2m u, th\u00ec s\u1ee3 m\u1ed3ng hai m\u1ed3ng ba m\u01b0a xu\u1ed1ng; kh\u00f4ng s\u1ee3 m\u01b0\u1eddi l\u0103m, m\u01b0\u1eddi s\u00e1u \u00e2m u, th\u00ec s\u1ee3 m\u01b0\u1eddi b\u1ea3y m\u01b0\u1eddi t\u00e1m m\u01b0a r\u01a1i\u201d, \u201cTr\u01b0\u1edbc xem m\u1ed3ng hai m\u1ed3ng ba, sau xem m\u01b0\u1eddi b\u1ea3y m\u01b0\u1eddi t\u00e1m\u201d. C\u00e2u ng\u1ea1n ng\u1eef th\u1ee9 nh\u1ea5t v\u00e0o ng\u00e0y m\u1ed3ng m\u1ed9t v\u00e0 m\u01b0\u1eddi l\u0103m m\u01b0\u1eddi s\u00e1u \u00e2m l\u1ecbch m\u00e0 tr\u1eddi \u00e2m u m\u1ed9t ch\u00fat c\u0169ng kh\u00f4ng \u0111\u00e1ng s\u1ee3, nh\u01b0ng n\u1ebfu ng\u00e0y m\u1ed3ng hai m\u1ed3ng ba ho\u1eb7c m\u01b0\u1eddi b\u1ea3y m\u01b0\u1eddi t\u00e1m m\u00e0 c\u00f3 m\u01b0a r\u01a1i th\u00ec m\u1ea5y ng\u00e0y k\u1ebf ti\u1ebfp sau \u0111\u00f3 m\u01b0a c\u00f3 th\u1ec3 c\u00e0ng to v\u00e0 k\u00e9o d\u00e0i h\u01a1n. C\u00e2u ng\u1ea1n ng\u1eef th\u1ee9 hai c\u00f3 ngh\u0129a l\u00e0 s\u1ef1 thay \u0111\u1ed5i th\u1eddi ti\u1ebft c\u1ee7a n\u1eeda th\u00e1ng \u0111\u1ea9u ch\u1ee7 y\u1ebfu n\u00ean theo d\u00f5i th\u1eddi ti\u1ebft ng\u00e0y m\u1ed3ng hai m\u1ed3ng ba, s\u1ef1 thay \u0111\u1ed5i th\u1eddi ti\u1ebft c\u1ee7a n\u1eeda th\u00e1ng sau ch\u1ee7 y\u1ebfu n\u00ean theo d\u00f5i th\u1eddi ti\u1ebft ng\u00e0y m\u01b0\u1eddi b\u1ea3y m\u01b0\u1eddi t\u00e1m. K\u1ef3 th\u1ef1c th\u00ec \u00fd ngh\u0129a c\u1ee7a hai c\u00e2u ng\u1ea1n ng\u1eef v\u1ec1 th\u1eddi ti\u1ebft n\u00e0y c\u0169ng t\u01b0\u01a1ng t\u1ef1 nhau. Hay nh\u01b0 v\u00f9ng l\u01b0u v\u1ef1c s\u00f4ng Tr\u01b0\u1eddng Giang Trung Qu\u1ed1c c\u00f3 c\u00e2u: \u201cB\u00e1n b\u1ee9c Nga Mi nguy\u1ec7t (ch\u1ec9 \u00e1nh tr\u0103ng ng\u00e0y \u00e2m l\u1ecbch \u0111\u1ea9u th\u00e1ng), vi\u1ec7t t\u00e0 t\u00e0 b\u1ea5t l\u1ea1c, vi\u1ec7t \u0111o\u1ea1n \u0111o\u1ea1n b\u1ea5t tr\u1ee5\u201d, \u201cminh nguy\u1ec7t chi\u1ebfu th\u1ea5p \u0111\u1ecba, b\u1ea5t l\u1ea1c ch\u00e2n hi k\u00ec\u201d, \u0111\u1ec1u l\u00e0 nh\u1eefng c\u00e2u ng\u1ea1n ng\u1eef v\u1ec1 th\u1eddi ti\u1ebft c\u00f3 li\u00ean quan t\u1edbi h\u00ecnh d\u1ea1ng tr\u0103ng. Mu\u1ed1n gi\u1ea3i \u0111\u00e1p v\u00ec sao c\u00f3 th\u1ec3 d\u1ef1a v\u00e0o h\u00ecnh d\u1ea1ng tr\u0103ng \u0111\u1ec3 d\u1ef1 b\u00e1o th\u1eddi ti\u1ebft, \u0111\u1ea9u ti\u00ean ph\u1ea3i hi\u1ec3u h\u00ecnh d\u1ea1ng tr\u0103ng l\u00e0 g\u00ec? H\u00ecnh d\u1ea1ng tr\u0103ng ch\u00ednh l\u00e0 s\u1ef1 thay \u0111\u1ed5i tr\u00f2n khuy\u1ebft c\u1ee7a M\u1eb7t tr\u0103ng. Trong m\u1ed9t th\u00e1ng \u00e2m l\u1ecbch, v\u1ecb tr\u00ed c\u1ee7a M\u1eb7t tr\u0103ng M\u1eb7t tr\u1eddi v\u00e0 Tr\u00e1i \u0111\u1ea5t \u0111\u1ec1u thay \u0111\u1ed5i. V\u00e0o l\u00fac M\u1eb7t tr\u0103ng \u1edf v\u00e0o v\u1ecb tr\u00ed ch\u00ednh gi\u1eefa M\u1eb7t tr\u1eddi v\u00e0 Tr\u00e1i \u0111\u1ea5t, t\u1eeb Tr\u00e1i \u0111\u1ea5t kh\u00f4ng th\u1ec3 nh\u00ecn th\u1ea5y s\u1ef1 ph\u1ea3n chi\u1ebfu tia s\u00e1ng M\u1eb7t tr\u1eddi c\u1ee7a M\u1eb7t tr\u1eddi, do \u0111\u00f3 l\u00fac n\u00e0y ta nh\u00ecn th\u1ea5y M\u1eb7t tr\u0103ng c\u00f3 m\u00e0u \u0111en, ng\u00e0y h\u00f4m \u0111\u00f3 ch\u00ednh l\u00e0 m\u1ed3ng m\u1ed9t \u00e2m l\u1ecbch, trong thi\u00ean v\u0103n h\u1ecdc g\u1ecdi l\u00e0 S\u00f3c. V\u00e0o l\u00fac M\u1eb7t tr\u1eddi v\u00e0 M\u1eb7t tr\u0103ng \u1edf hai n\u1eeda Tr\u00e1i \u0111\u1ea5t v\u00e0 c\u00f9ng v\u1edbi Tr\u00e1i \u0111\u1ea5t t\u1ea1o th\u00e0nh m\u1ed9t \u0111\u01b0\u1eddng th\u1eb3ng, l\u00fac n\u00e0y nh\u00ecn t\u1eed Tr\u00e1i \u0111\u1ea5t th\u1ea5y M\u1eb7t tr\u0103ng tr\u00f2n nh\u1ea5t v\u00e0 s\u00e1ng nh\u1ea5t, ng\u00e0y \u0111\u00f3 \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 V\u1ecdng, ch\u00ednh l\u00e0 ng\u00e0y m\u01b0\u1eddi l\u0103m, m\u01b0\u1eddi s\u00e1u \u00e2m l\u1ecbch. L\u00fac M\u1eb7t tr\u0103ng, M\u1eb7t tr\u1eddi v\u00e0 Tr\u00e1i \u0111\u1ea5t t\u1ea1o th\u00e0nh g\u00f3c vu\u00f4ng 90 \u0111\u1ed9, nh\u00ecn t\u1eeb Tr\u00e1i \u0111\u1ea5t th\u1ea5y n\u1eeda b\u00ean ph\u1ea3i s\u00e1ng, ng\u00e0y h\u00f4m \u0111\u00f3 g\u1ecdi l\u00e0 Th\u01b0\u1ee3ng huy\u1ec1n, ch\u00ednh l\u00e0 m\u1ed3ng t\u00e1m ho\u1eb7c m\u1ed3ng ch\u00edn \u00e2m l\u1ecbch. L\u00fac M\u1eb7t tr\u0103ng, M\u1eb7t tr\u1eddi v\u00e0 Tr\u00e1i \u0111\u1ea5t t\u1ea1o th\u00e0nh g\u00f3c 270 \u0111\u1ed9, nh\u00ecn t\u1eeb Tr\u00e1i \u0111\u1ea5t th\u1ea5y M\u1eb7t tr\u0103ng s\u00e1ng n\u1eeda b\u00ean tr\u00e1i, ng\u00e0y h\u00f4m \u0111\u00f3 g\u1ecdi l\u00e0 H\u1ea1 huy\u1ec1n, ch\u00ednh l\u00e0 hai hai ho\u1eb7c hai ba \u00e2m l\u1ecbch. Do \u0111\u00f3 chu k\u1ef3 bi\u1ebfn \u0111\u1ed5i tr\u00f2n khuy\u1ebft c\u1ee7a M\u1eb7t tr\u0103ng (t\u1ee9c l\u00e0 chu k\u1ef3 d\u1ea1ng tr\u0103ng) ch\u00ednh l\u00e0 m\u1ed9t th\u00e1ng \u00e2m l\u1ecbch, l\u1ea1i c\u0169ng \u0111\u00fang l\u00e0 m\u1ed9t th\u00e1ng s\u00f3c v\u1ecdng trong thi\u00ean v\u0103n h\u1ecdc. Ch\u00fang ta bi\u1ebft r\u1eb1ng M\u1eb7t tr\u1eddi v\u00e0 M\u1eb7t tr\u0103ng c\u00f3 l\u1ef1c d\u1eabn tri\u1ec1u \u0111\u1ed1i v\u1edbi Tr\u00e1i \u0111\u1ea5t, c\u00f3 th\u1ec3 l\u00e0m cho n\u01b0\u1edbc bi\u1ec3n d\u00e2ng l\u00ean h\u1ea1 xu\u1ed1ng, c\u0169ng c\u00f3 th\u1ec3 khi\u1ebfn l\u1edbp v\u1ecf Tr\u00e1i \u0111\u1ea5t chuy\u1ec3n \u0111\u1ed9ng l\u00ean xu\u1ed1ng. \u0110\u00f3 ch\u00ednh l\u00e0 thu\u1ef7 tri\u1ec1u v\u00e0 tri\u1ec1u \u0111\u1eb7c. Tr\u01b0\u1edbc \u0111\u00e2y nhi\u1ec1u ng\u01b0\u1eddi t\u01b0\u1edfng r\u1eb1ng \u1ea3nh","h\u01b0\u1edfng c\u1ee7a l\u1ef1c d\u1eabn tri\u1ec1u \u0111\u1ed1i v\u1edbi kh\u00ed quy\u1ec3n kh\u00f4ng l\u1edbn. Nh\u01b0ng g\u1ea9n 20 n\u0103m tr\u1edf l\u1ea1i \u0111\u00e2y, c\u00e1c nh\u00e0 khoa h\u1ecdc Trung Qu\u1ed1c nghi\u00ean c\u1ee9u v\u00e0 ph\u00e1t hi\u1ec7n ra r\u1eb1ng l\u1ef1c d\u1eabn tri\u1ec1u c\u1ee7a M\u1eb7t tr\u0103ng v\u00e0 M\u1eb7t tr\u1eddi c\u00f3 t\u00e1c \u0111\u1ed9ng r\u1ea5t l\u1edbn t\u1edbi s\u1ef1 v\u1eadn \u0111\u1ed9ng c\u1ee7a kh\u00ed quy\u1ec3n v\u00e0 s\u1ef1 thay \u0111\u1ed5i th\u1eddi ti\u1ebft, \u0111\u1eb7c bi\u1ec7t nh\u1eefng thay \u0111\u1ed5i th\u1eddi ti\u1ebft \u0111\u1ed9t ng\u1ed9t v\u00e0 nh\u1eefng ph\u00e1t sinh nguy h\u1ea1i c\u1ee7a th\u1eddi ti\u1ebft th\u01b0\u1eddng c\u00f3 li\u00ean quan t\u1edbi s\u1ef1 thay \u0111\u1ed5i c\u1ee7a l\u1ef1c d\u1eabn tri\u1ec1u. Trong m\u1ed9t th\u00e1ng \u00e2m l\u1ecbch, ng\u00e0y S\u00f3c v\u00e0 ng\u00e0y V\u1ecdng l\u00e0 l\u00fac l\u1ef1c d\u1eabn tri\u1ec1u c\u1ee7a M\u1eb7t tr\u0103ng v\u00e0 M\u1eb7t tr\u1eddi h\u1ee3p l\u1ea1i \u1edf m\u1ee9c cao nh\u1ea5t, sau \u0111\u00f3 h\u1ee3p l\u1ef1c c\u1ee7a l\u1ef1c d\u1eabn tri\u1ec1u d\u1ea9n d\u1ea9n gi\u1ea3m \u0111i. N\u1ebfu v\u00e0o m\u1ed3ng m\u1ed9t \u00e2m l\u1ecbch (S\u00f3c) v\u00e0 m\u01b0\u1eddi l\u0103m m\u01b0\u1eddi s\u00e1u \u00e2m l\u1ecbch (V\u1ecdng) th\u1eddi ti\u1ebft kh\u00f4ng chuy\u1ec3n t\u1eeb s\u00e1ng s\u1ee7a sang \u00e2m u, th\u00ec v\u00e0o m\u1ed3ng hai m\u1ed3ng ba \u00e2m l\u1ecbch ho\u1eb7c m\u01b0\u1eddi b\u1ea3y m\u01b0\u1eddi t\u00e1m \u00e2m l\u1ecbch th\u1eddi ti\u1ebft s\u1ebd chuy\u1ec3n x\u1ea5u, cho th\u1ea5y r\u1eb1ng l\u1ef1c d\u1eabn tri\u1ec1u c\u00f3 th\u1ec3 c\u00f3 nh\u1eefng thay \u0111\u1ed5i kh\u00e1c th\u01b0\u1eddng, ho\u1eb7c c\u00f3 th\u1ec3 c\u00f3 qu\u00e1 tr\u00ecnh th\u1eddi ti\u1ebft kh\u00e1 l\u1edbn \u1ea3nh h\u01b0\u1edfng t\u1edbi n\u01a1i \u0111\u00f3, b\u00e1o tr\u01b0\u1edbc r\u1eb1ng trong kho\u1ea3ng th\u1eddi gian s\u1eafp t\u1edbi th\u1eddi ti\u1ebft c\u00f3 th\u1ec3 s\u1ebd ti\u1ebfp t\u1ee5c x\u1ea5u \u0111i, ph\u1ea3i \u0111\u1ec1 ph\u00f2ng tr\u01b0\u1edbc s\u1ef1 chuy\u1ec3n bi\u1ebfn x\u1ea5u c\u1ee7a th\u1eddi ti\u1ebft. \u0110\u00f3 ch\u00ednh l\u00e0 \u00fd ngh\u0129a c\u1ee7a c\u00e2u \u201ckh\u00f4ng s\u1ee3 m\u1ed3ng m\u1ed9t \u00e2m u th\u00ec s\u1ee3 m\u1ed3ng hai m\u1ed3ng ba m\u01b0a xu\u1ed1ng\u201d. D\u1ef1a v\u00e0o d\u1ea1ng tr\u0103ng \u0111\u1ec3 d\u1ef1 b\u00e1o th\u1eddi ti\u1ebft l\u00e0 c\u00f3 c\u01a1 s\u1edf khoa h\u1ecdc nh\u1ea5t \u0111\u1ecbnh. Nh\u01b0 ng\u00e0y nay c\u00e1c nh\u00e0 kh\u00ed t\u01b0\u1ee3ng \u0111\u00e3 v\u1ec1 c\u01a1 b\u1ea3n l\u00e0m r\u00f5 \u0111\u01b0\u1ee3c \u1ea3nh h\u01b0\u1edfng c\u1ee5 th\u1ec3 c\u1ee7a l\u1ef1c d\u1eabn tri\u1ec1u \u0111\u1ed1i v\u1edbi th\u1eddi ti\u1ebft, \u0111\u1ed3ng th\u1eddi c\u00f3 th\u1ec3 tr\u1ef1c ti\u1ebfp d\u1ef1a v\u00e0o s\u1ef1 thay \u0111\u1ed5i c\u1ee7a l\u1ef1c d\u1eabn tri\u1ec1u, k\u1ebft h\u1ee3p v\u1edbi nh\u1eefng bi\u1ebfn \u0111\u1ed5i c\u1ee7a t\u00ecnh h\u00ecnh th\u1eddi ti\u1ebft nh\u01b0 \u00e1p su\u1ea5t cao, \u00e1p su\u1ea5t th\u1ea5p \u0111\u1ec3 d\u1ef1 \u0111o\u00e1n s\u1ef1 thay \u0111\u1ed5i c\u1ee7a th\u1eddi ti\u1ebft s\u1eafp t\u1edbi. T\u1ea1i sao c\u00f3 th\u1ec3 th\u1ea5y M\u1eb7t tr\u0103ng gi\u1eefa ban ng\u00e0y? M\u1eb7t tr\u0103ng xu\u1ea5t hi\u1ec7n v\u00e0o ban ng\u00e0y c\u0169ng nhi\u1ec1u nh\u01b0 v\u00e0o ban \u0111\u00eam. Ch\u1ec9 c\u00f3 \u0111i\u1ec1u ban ng\u00e0y M\u1eb7t tr\u1eddi s\u00e1ng h\u01a1n t\u1ea5t c\u1ea3 m\u1ecdi th\u1ee9, s\u00e1ng \u0111\u1ebfn n\u1ed7i ch\u00fang ta kh\u00f4ng th\u1ec3 nh\u1eadn ra M\u1eb7t tr\u0103ng ngay c\u1ea3 khi n\u00f3 \u0111ang xu\u1ea5t hi\u1ec7n. Tuy v\u1eady, v\u00e0o ban \u0111\u00eam ch\u1ecb H\u1eb1ng l\u00e0 th\u1ee9 s\u00e1ng nh\u1ea5t tr\u00ean b\u1ea9u tr\u1eddi. Do M\u1eb7t tr\u0103ng di chuy\u1ec3n quanh Tr\u00e1i \u0111\u1ea5t trong m\u1ed9t th\u00e1ng, n\u00ean n\u00f3 c\u00f3 m\u1eb7t \u1edf m\u1ecdi v\u1ecb tr\u00ed tr\u00ean b\u1ea9u tr\u1eddi trong su\u1ed1t 24 gi\u1edd. Di\u1ec7n t\u00edch b\u1ec1 m\u1eb7t M\u1eb7t tr\u0103ng \u0111\u01b0\u1ee3c nh\u00ecn th\u1ea5y ph\u1ee5 thu\u1ed9c v\u00e0o tu\u1ea9n tr\u0103ng, hay v\u00e0o di\u1ec7n t\u00edch m\u00e0 n\u00f3 \u0111\u01b0\u1ee3c \u00e1nh M\u1eb7t tr\u1eddi chi\u1ec1u t\u1edbi t\u1ea1i m\u1ed9t th\u1eddi \u0111i\u1ec3m nh\u1ea5t \u0111\u1ecbnh. Ban ng\u00e0y tr\u1eddi s\u00e1ng v\u00ec b\u1ea9u kh\u00ed quy\u1ec3n t\u00e1n x\u1ea1 \u00e1nh M\u1eb7t tr\u1eddi, nh\u01b0ng M\u1eb7t tr\u0103ng \u0111\u1ee7 g\u1ea9n v\u00e0 \u0111\u1ee7 to \u0111\u1ec3 ph\u1ea3n chi\u1ebfu \u0111\u1ee7 \u00e1nh M\u1eb7t tr\u1eddi n\u00ean n\u00f3 s\u00e1ng h\u01a1n b\u1ea9u tr\u1eddi xung quanh. V\u00ec th\u1ebf ta v\u1eabn th\u1ea5y M\u1eb7t tr\u0103ng. Song \u0111i\u1ec1u n\u00e0y kh\u00f4ng \u0111\u00fang v\u1edbi c\u00e1c v\u00ec sao. Tuy v\u1eady, m\u1ed9t nh\u00e0 du h\u00e0nh tr\u00ean M\u1eb7t tr\u0103ng th\u1eadm ch\u00ed v\u1eabn c\u00f3 th\u1ec3 nh\u00ecn th\u1ea5y c\u00e1c v\u00ec sao khi m\u00e0 M\u1eb7t tr\u1eddi \u0111ang m\u1ecdc, b\u1edfi v\u00ec tr\u00ean th\u1ef1c t\u1ebf M\u1eb7t tr\u0103ng kh\u00f4ng c\u00f3 b\u1ea9u kh\u00ed quy\u1ec3n \u0111\u1ec3 ph\u00e2n t\u00e1n \u00e1nh M\u1eb7t tr\u1eddi v\u00e0 l\u00e0m s\u00e1ng lo\u00e1 b\u1ea9u tr\u1eddi ban ng\u00e0y. L\u00e0m th\u1ebf n\u00e0o \u0111\u1ec3 b\u1ea3o v\u1ec7 m\u00ecnh gi\u1eefa c\u01a1n d\u00f4ng? Trong c\u01a1n d\u00f4ng, \u0111\u00e1ng s\u1ee3 nh\u1ea5t kh\u00f4ng ph\u1ea3i l\u00e0 b\u1ea9u tr\u1eddi \u0111en k\u1ecbt, gi\u00f3 r\u00edt \u00e0o \u00e0o, s\u1ea5m","gi\u1eadt hay m\u00e0n n\u01b0\u1edbc t\u00e1p xi\u00ean v\u00e0o m\u1eb7t, m\u00e0 l\u00e0 nh\u1eefng c\u00fa s\u00e9t ch\u1ebft ng\u01b0\u1eddi \u0111\u00e1nh xu\u1ed1ng \u0111\u1ea5t. D\u01b0\u1edbi \u0111\u00e2y l\u00e0 l\u1eddi khuy\u00ean c\u1ee7a c\u00e1c chuy\u00ean gia n\u1ebfu b\u1ea1n ch\u1ec9 c\u00f3 m\u1ed9t m\u00ecnh trong c\u01a1n d\u00f4ng. Tr\u00ean c\u00e1c c\u00e1nh \u0111\u1ed3ng Tr\u01b0\u1edbc ti\u00ean, \u0111\u1ec3 kh\u00f4ng b\u1ecb \u0111e do\u1ea1 b\u1edfi nguy c\u01a1 c\u00e1i c\u00e2y \u0111\u1ed5 xu\u1ed1ng \u0111\u1ee9ng \u0111\u1ea9u, b\u1ea1n h\u00e3y tr\u00e1nh xa c\u00e1c g\u1ed1c c\u00e2y, \u0111\u1eb7c bi\u1ec7t l\u00e0 nh\u1eefng c\u00e2y \u0111\u1ee9ng ri\u00eang l\u1ebb. Th\u1ef1c t\u1ebf l\u00e0 nh\u1eefng ng\u1ecdn gi\u00f3 m\u1ea1nh trong su\u1ed1t c\u01a1n m\u01b0a khi\u1ebfn cho kh\u1ea3 n\u0103ng che m\u01b0a c\u1ee7a c\u00e2y kh\u00f4ng c\u00f2n, nh\u1ea5t l\u00e0 khi tr\u1eddi m\u01b0a nh\u01b0 tr\u00fat n\u01b0\u1edbc. Sau n\u1eefa, v\u1edbi \u0111\u1ed9 cao c\u1ee7a n\u00f3, c\u00e2y thu h\u00fat s\u00e9t. V\u00e0 v\u00ec khung x\u01b0\u01a1ng c\u1ee7a ng\u01b0\u1eddi c\u00f3 \u0111i\u1ec7n tr\u1edf nh\u1ecf h\u01a1n g\u1ed7, n\u00ean ch\u00fang ta s\u1ebd l\u00e0 m\u1ed9t ph\u01b0\u01a1ng ti\u1ec7n t\u1ed1t h\u01a1n cho s\u00e9t ti\u1ebfp \u0111\u1ea5t. Khi b\u1ea1n \u0111\u1ee9ng c\u00e1ch xa c\u00e2y, th\u1eadm ch\u00ed khi \u0111\u1ee9ng th\u1eb3ng, c\u0169ng gi\u1ea3m nguy c\u01a1 thu h\u00fat s\u00e9t h\u01a1n 50 l\u1ea9n. Th\u1ebf nh\u01b0ng nguy hi\u1ec3m v\u1eabn c\u00f2n. Ng\u01b0\u1eddi n\u00f4ng d\u00e2n, v\u1edbi c\u00e1c d\u1ee5ng c\u1ee5 b\u1eb1ng s\u1eaft tr\u00ean tay, c\u0169ng v\u00f4 t\u00ecnh bi\u1ebfn m\u00ecnh th\u00e0nh m\u1ee5c ti\u00eau c\u1ee7a s\u00e9t. V\u00ec v\u1eady, c\u00e1ch t\u1ed1t nh\u1ea5t khi g\u1eb7p d\u00f4ng t\u1ed1 \u1edf n\u01a1i tr\u1ed1ng tr\u1ea3i nh\u01b0 c\u00e1nh \u0111\u1ed3ng l\u00e0 qu\u1ef3 xu\u1ed1ng \u0111\u1ea5t. D\u00f9 c\u00f3 h\u01a1i b\u1ea9n, nh\u01b0ng b\u1ea1n \u00edt c\u00f3 nguy c\u01a1 ch\u1ea1m tr\u00e1n Thi\u00ean L\u00f4i. C\u00f2n n\u1ebfu \u0111ang b\u01a1i M\u1ed9t t\u00ecnh hu\u1ed1ng nguy hi\u1ec3m! S\u00e9t kh\u00f4ng c\u1ea9n \u0111\u00e1nh tr\u1ef1c ti\u1ebfp l\u00ean m\u1ed9t ng\u01b0\u1eddi \u0111ang b\u01a1i v\u1eabn c\u00f3 th\u1ec3 bi\u1ebfn anh ta tr\u1edf th\u00e0nh n\u1ea1n nh\u00e2n. V\u00ec th\u1ef1c t\u1ebf d\u00f2ng \u0111i\u1ec7n t\u1eeb tr\u00ean tr\u1eddi kh\u00f4ng bi\u1ebfn m\u1ea5t ngay khi n\u00f3 \u0111\u00e1nh xu\u1ed1ng \u0111\u1ea5t, m\u00e0 ch\u1ec9 y\u1ebfu d\u1ea9n trong m\u00f4i tr\u01b0\u1eddng \u0111\u1ea5t. B\u1edfi v\u00ec n\u01b0\u1edbc l\u00e0 m\u1ed9t ch\u1ea5t d\u1eabn \u0111i\u1ec7n r\u1ea5t t\u1ed1t. Do v\u1eady, khi \u0111\u00e1nh xu\u1ed1ng n\u01b0\u1edbc, ho\u1eb7c xu\u1ed1ng m\u1eb7t \u0111\u1ea5t \u1edf g\u1ea9n \u0111\u00f3, d\u00f2ng \u0111i\u1ec7n s\u1ebd r\u1ea5t d\u1ec5 d\u00e0ng ch\u1ea1y t\u1edbi ng\u01b0\u1eddi. V\u00ec v\u1eady, kh\u00f4ng n\u00ean b\u01a1i khi tr\u1eddi n\u1ed5i d\u00f4ng. Trong xe h\u01a1i Chi\u1ebfc xe l\u00e0 m\u1ed9t n\u01a1i \u1ea9n n\u1ea5p an to\u00e0n trong c\u01a1n d\u00f4ng. \u1ede \u0111\u00e2y, n\u00f3 \u0111\u00f3ng vai tr\u00f2 t\u01b0\u01a1ng t\u1ef1 nh\u01b0 m\u1ed9t \u201cchi\u1ebfc l\u1ed3ng Faraday\u201d (t\u00ean c\u1ee7a nh\u00e0 khoa h\u1ecdc \u0111\u1ea9u ti\u00ean ch\u1ee9ng minh r\u1eb1ng vi\u1ec7c \u1ea9n m\u00ecnh ph\u00eda trong m\u1ed9t c\u1ea5u tr\u00fac b\u1eb1ng kim lo\u1ea1i l\u00e0 bi\u1ec7n ph\u00e1p t\u1ed1t nh\u1ea5t \u0111\u1ec3 tr\u00e1nh s\u00e9t). N\u1ebfu s\u00e9t \u0111\u00e1nh tr\u00fang xe th\u00ec \u0111i\u1ec7n s\u1ebd d\u1eabn truy\u1ec1n tr\u00ean v\u1ecf xe m\u00e0 kh\u00f4ng xuy\u00ean v\u00e0o ph\u00eda trong tr\u01b0\u1edbc khi ti\u1ebfp x\u00fac v\u1edbi m\u1eb7t \u0111\u1ea5t. Do v\u1ecf xe b\u1eb1ng kim lo\u1ea1i d\u1eabn \u0111i\u1ec7n t\u1ed1t h\u01a1n nhi\u1ec1u so v\u1edbi kh\u00f4ng kh\u00ed trong xe, n\u00ean d\u00f2ng \u0111i\u1ec7n c\u1ef1c m\u1ea1nh c\u1ee7a s\u00e9t s\u1ebd \u0111\u01b0\u1ee3c truy\u1ec1n nhanh ch\u00f3ng xu\u1ed1ng m\u1eb7t \u0111\u1ea5t. Tuy nhi\u00ean, trong t\u00ecnh hu\u1ed1ng n\u00e0y, nh\u1eefng ng\u01b0\u1eddi ng\u1ed3i trong xe tuy\u1ec7t \u0111\u1ed1i kh\u00f4ng \u0111\u01b0\u1ee3c s\u1edd v\u00e0o m\u00e1y thu thanh hay b\u1ea5t k\u1ef3 m\u1ed9t b\u1ed9 ph\u1eadn kimlo\u1ea1i n\u00e0o kh\u00e1c c\u1ee7a xe. V\u00e0 nh\u1ea5t l\u00e0 kh\u00f4ng \u0111\u01b0\u1ee3c b\u1ecf mui. Tr\u00ean m\u00e1y bay Tr\u01b0\u1edbc ti\u00ean, c\u1ea9n ph\u1ea3i bi\u1ebft r\u1eb1ng m\u00e1y bay th\u01b0\u1eddng xuy\u00ean b\u1ecb s\u00e9t \u0111\u00e1nh. Trung b\u00ecnh c\u1ee9","sau 5.000 hay 10.000 gi\u1edd bay, m\u1ed9t chi\u1ebfc m\u00e1y bay s\u1ebd b\u1ecb s\u00e9t \u0111\u00e1nh m\u1ed9t l\u1ea9n. Nh\u01b0ng \u0111\u00f3 l\u00e0 hi\u1ec7n t\u01b0\u1ee3ng b\u00ecnh th\u01b0\u1eddng, kh\u00f4ng \u0111\u1ec3 l\u1ea1i h\u1eadu qu\u1ea3. Nh\u1edd v\u00e0o l\u1edbp v\u1ecf kim lo\u1ea1i, m\u00e1y bay truy\u1ec1n \u0111i\u1ec7n c\u1ee7a s\u00e9t m\u00e0 kh\u00f4ng g\u1eb7p tr\u1edf ng\u1ea1i g\u00ec, v\u00ec l\u00fac \u0111\u00f3, n\u00f3 ch\u1ec9 tr\u1edf th\u00e0nh v\u1eadt th\u1ebf ch\u00e2n trong m\u1ed9t v\u00e0i gi\u00e2y \u0111\u01b0\u1eddng truy\u1ec1n t\u1ef1 nhi\u00ean c\u1ee7a s\u00e9t trong kh\u00f4ng kh\u00ed. Do v\u1eady, khi phi c\u00f4ng t\u00ecm c\u00e1ch \u0111i tr\u00e1nh c\u01a1n d\u00f4ng, \u0111\u00f3 kh\u00f4ng ph\u1ea3i l\u00e0 v\u00ec anh ta s\u1ee3 s\u00e9t, m\u00e0 l\u00e0 v\u00ec c\u00e1c d\u00f2ng kh\u00ed m\u1ea1nh do hi\u1ec7n t\u01b0\u1ee3ng th\u1eddi ti\u1ebft n\u00e0y m\u1edbi th\u1ef1c s\u1ef1 nguy hi\u1ec3m, \u0111\u1eb7c bi\u1ec7t khi ti\u1ebfp \u0111\u1ea5t v\u00e0 c\u1ea5t c\u00e1nh. V\u00ec sao tr\u01b0\u1edbc c\u01a1n m\u01b0a r\u00e0o tr\u1eddi r\u1ea5t oi b\u1ee9c? Bu\u1ed5i s\u00e1ng, M\u1eb7t tr\u1eddi v\u1eeba m\u1edbi m\u1ecdc m\u00e0 kh\u00f4ng kh\u00ed \u0111\u00e3 r\u1ea5t n\u00f3ng n\u1ef1c, qu\u1ea1t quay t\u00edt nh\u01b0ng m\u1ed3 h\u00f4i m\u1ed3 k\u00ea b\u1ea1n r\u1ea5t nh\u1ec5 nh\u1ea1i. Tr\u1eddi kh\u00f4ng ch\u1ec9 n\u00f3ng b\u1ee9c m\u00e0 c\u00f2n ng\u1ed9t ng\u1ea1t n\u1eefa: \u0110\u00f3 ch\u00ednh l\u00e0 d\u1ea5u hi\u1ec7u b\u1eaft \u0111\u1ea9u c\u1ee7a m\u1ed9t c\u01a1n m\u01b0a r\u00e0o. M\u01b0a r\u00e0o th\u01b0\u1eddng x\u1ea3y ra v\u00e0o m\u00f9a h\u00e8. Mu\u1ed1n c\u00f3 m\u01b0a r\u00e0o c\u1ea9n ph\u1ea3i c\u00f3 hai \u0111i\u1ec1u ki\u1ec7n. M\u1ed9t l\u00e0 nhi\u1ec7t \u0111\u1ed9 m\u1eb7t \u0111\u1ea5t cao, hai l\u00e0 kh\u00f4ng kh\u00ed ph\u1ea3i c\u00f3 \u0111\u1ed9 \u1ea9m cao. M\u1eb7t \u0111\u1ea5t n\u00f3ng l\u00e0m l\u1edbp kh\u00f4ng kh\u00ed s\u00e1t m\u1eb7t \u0111\u1ea5t c\u0169ng \u1ea5m l\u00ean, tr\u1edf n\u00ean nh\u1eb9 h\u01a1n v\u00e0 bay l\u00ean kh\u00f4ng trung. Nh\u01b0ng n\u1ebfu n\u00f3ng m\u00e0 kh\u00f4ng kh\u00ed l\u1ea1i kh\u00f4 r\u00e1o th\u00ec m\u01b0a r\u00e0o kh\u00f4ng th\u1ec3 x\u1ea3y ra. Ch\u1ec9 khi \u0111\u1ed9 \u1ea9m cao, h\u01a1i n\u01b0\u1edbc b\u1ed1c l\u00ean tr\u00ean tr\u1eddi h\u00ecnh th\u00e0nh m\u00e2y v\u0169 t\u00edch th\u00ec m\u1edbi c\u00f3 kh\u1ea3 n\u0103ng cho m\u01b0a \u0111\u01b0\u1ee3c. Kh\u00f4ng kh\u00ed \u0111\u00e3 n\u00f3ng l\u1ea1i \u1ea9m, khi\u1ebfn cho n\u01b0\u1edbc \u1edf b\u1ec1 m\u1eb7t Tr\u00e1i \u0111\u1ea5t kh\u00f4ng th\u1ec3 b\u1ed1c h\u01a1i \u0111\u01b0\u1ee3c. M\u1ed3 h\u00f4i tr\u00ean c\u01a1 th\u1ec3 ng\u01b0\u1eddi c\u0169ng kh\u00f3 kh\u00f4 \u0111i. Khi \u1ea5y ta c\u1ea3m th\u1ea5y oi b\u1ee9c ng\u1ed9t ng\u1ea1t kh\u00f3 ch\u1ecbu. C\u1ea3m gi\u00e1c \u0111\u00f3 t\u01b0\u01a1ng t\u1ef1 nh\u01b0 khi ta \u1edf trong bu\u1ed3ng t\u1eafm k\u00edn m\u00f9a h\u00e8, v\u1edbi \u0111\u1ed9 \u1ea9m l\u1edbn \u0111\u1ed3ng th\u1eddi nhi\u1ec7t \u0111\u1ed9 cao. V\u00ec th\u1ebf, khi b\u1ea1n c\u1ea3m th\u1ea5y oi b\u1ee9c t\u1ee9c l\u00e0 kh\u00f4ng kh\u00ed xung quanh v\u1eeba c\u00f3 \u0111\u1ed9 \u1ea9m l\u1edbn, v\u1eeba c\u00f3 nhi\u1ec7t \u0111\u1ed9 cao, \u0111\u1ee7 \u0111i\u1ec1u ki\u1ec7n \u0111\u1ec3 cho m\u1ed9t c\u01a1n m\u01b0a r\u00e0o x\u1ea3y ra. Nh\u01b0ng \u0111\u00f4i khi hi\u1ec7n t\u01b0\u1ee3ng kh\u00f4ng kh\u00ed oi b\u1ee9c x\u1ea3y ra m\u00e0 v\u1eabn kh\u00f4ng h\u1ec1 c\u00f3 m\u01b0a. \u0110\u00f3 l\u00e0 v\u00ec ph\u1ea1m vi c\u1ee7a nh\u1eefng c\u01a1n m\u01b0a m\u00f9a h\u1ea1 t\u01b0\u01a1ng \u0111\u1ed1i nh\u1ecf. C\u00f3 th\u1ec3 \u1edf \u0111\u00e2u \u0111\u00f3 \u0111ang m\u01b0a r\u00e0o nh\u01b0ng \u1edf ch\u1ed7 ch\u00fang ta l\u1ea1i kh\u00f4ng. \u0110i\u1ec1u g\u00ec quy\u1ebft \u0111\u1ecbnh s\u1ef1 to nh\u1ecf c\u1ee7a h\u1ea1t m\u01b0a \u0111\u00e1? Kh\u00f4ng ph\u1ea3i c\u1ee9 b\u1ea9u tr\u1eddi c\u00e0ng nhi\u1ec1u n\u01b0\u1edbc th\u00ec h\u1ea1t m\u01b0a \u0111\u00e1 c\u00e0ng to. C\u00e1c nh\u00e0 nghi\u00ean c\u1ee9u cho bi\u1ebft s\u1ee9c m\u1ea1nh c\u1ee7a c\u00e1c d\u00f2ng kh\u00f4ng kh\u00ed chuy\u1ec3n \u0111\u1ed9ng l\u00ean ph\u00eda tr\u00ean trong c\u01a1n b\u00e3o s\u1ea5m m\u1edbi l\u00e0 y\u1ebfu t\u1ed1 quy\u1ebft \u0111\u1ecbnh k\u00edch c\u1ee1 c\u1ee7a ch\u00fang. T\u1ea1i n\u01a1i c\u01a1n b\u00e3o xu\u1ea5t hi\u1ec7n, kh\u00f4ng kh\u00ed chuy\u1ec3n \u0111\u1ed9ng l\u00ean tr\u00ean r\u1ea5t nhanh. Khi \u0111\u1ea1t \u0111\u1ebfn \u0111\u1ed9 cao nh\u1ea5t \u0111\u1ecbnh, lu\u1ed3ng kh\u00f4ng kh\u00ed n\u00e0y l\u1ea1nh \u0111i, h\u01a1i n\u01b0\u1edbc trong c\u00e1c h\u1ea1t n\u01b0\u1edbc b\u1ed1c h\u01a1i ng\u01b0ng t\u1ee5 l\u1ea1i th\u00e0nh m\u1ed9t \u0111\u00e1m m\u00e2y b\u00e3o. Cu\u1ed1i c\u00f9ng, s\u1ef1 k\u1ebft t\u1ee7a \u0111\u01b0\u1ee3c t\u1ea1o th\u00e0nh trong c\u00e1c \u0111\u00e1m m\u00e2y, \u0111\u1ea9u ti\u00ean gi\u1ed1ng nh\u01b0 c\u00e1c v\u1ea9y tuy\u1ebft, sau \u0111\u00f3 gi\u1ed1ng nh\u01b0 c\u00e1c h\u1ea1t m\u01b0a. N\u1ebfu c\u00e1c h\u1ea1t m\u01b0a n\u00e0y l\u1ea1i b\u1ecb b\u1eaft l\u1ea1i v\u00e0o lu\u1ed3ng kh\u00f4ng kh\u00ed chuy\u1ec3n \u0111\u1ed9ng l\u00ean tr\u00ean m\u1ed9t l\u1ea9n n\u1eefa, n\u00f3 s\u1ebd ti\u1ebfp t\u1ee5c di chuy\u1ec3n v\u01b0\u1ee3t l\u00ean tr\u00ean m\u1ee9c \u0111\u00f3ng b\u0103ng, v\u00e0 tr\u1edf th\u00e0nh m\u1ed9t qu\u1ea3","b\u00f3ng nh\u1ecf b\u1eb1ng n\u01b0\u1edbc \u0111\u00e1. H\u1ea1t n\u01b0\u1edbc \u0111\u00e1 n\u00e0y ti\u1ebfp nh\u1eadn th\u00eam c\u00e1c h\u1ea1t \u0111\u00e1 nh\u1ecf li ti trong m\u00f4i tr\u01b0\u1eddng xung quanh, v\u00e0 cu\u1ed1i c\u00f9ng, khi \u0111\u00e3 \u0111\u1ee7 n\u1eb7ng, n\u00f3 r\u01a1i xu\u1ed1ng, v\u00e0 r\u1ed3i l\u1ea1i b\u1ecb gi\u1eef l\u1ea1i trong s\u1ef1 ho\u1ea1t \u0111\u1ed9ng h\u1ed7n lo\u1ea1n c\u1ee7a kh\u00f4ng kh\u00ed. V\u1edbi m\u1ed7i chuy\u1ebfn \u0111i l\u00ean v\u00e0 \u0111i xu\u1ed1ng nh\u01b0 v\u1eady, h\u1ea1t m\u01b0a \u0111\u00e1 l\u1ea1i \u0111\u01b0\u1ee3c b\u1ed5 sung th\u00eam c\u00e1c ch\u1ea5t m\u1edbi. Khi c\u1eaft ngang qua m\u1ed9t h\u1ea1t m\u01b0a nh\u01b0 v\u1eady, ta s\u1ebd th\u1ea5y c\u00e1c l\u1edbp gi\u1ed1ng nh\u01b0 v\u00f2ng tu\u1ed5i c\u1ee7a c\u00e2y, cho bi\u1ebft n\u00f3 \u0111\u00e3 th\u1ef1c hi\u1ec7n bao nhi\u00eau chuy\u1ebfn \u0111i \u201ckh\u1ee9 h\u1ed3i\u201d. Nh\u1eefng v\u00f9ng kh\u00f4ng kh\u00ed ho\u1ea1t \u0111\u1ed9ng h\u1ed7n lo\u1ea1n l\u00e0 nh\u1eefng n\u01a1i sinh ra c\u00e1c h\u1ea1t m\u01b0a \u0111\u00e1 l\u1edbn nh\u1ea5t. \u01af\u1edbc t\u00ednh lu\u1ed3ng kh\u00f4ng kh\u00ed chuy\u1ec3n \u0111\u1ed9ng l\u00ean ph\u00eda tr\u00ean v\u1edbi v\u1eadn t\u1ed1c kho\u1ea3ng 160 km\/ h c\u00f3 th\u1ec3 t\u1ea1o ra c\u00e1c h\u1ea1t m\u01b0a \u0111\u00e1 c\u00f3 \u0111\u01b0\u1eddng k\u00ednh 12 c\u00e1ch m\u1ea1ng ho\u1eb7c h\u01a1n. M\u1ed9t h\u1ea1t m\u01b0a \u0111\u00e1 n\u1ed5i ti\u1ebfng r\u01a1i xu\u1ed1ng Coffeyville, Kansasn\u0103m 1979 c\u00e2n n\u1eb7ng 750 gram, c\u00f3 \u0111\u01b0\u1eddng k\u00ednh kho\u1ea3ng 20 centimet. V\u00ec sao m\u01b0a \u0111\u00e1 ch\u1ec9 xu\u1ea5t hi\u1ec7n v\u00e0o m\u00f9a n\u00f3ng? V\u00e0o cu\u1ed1i m\u00f9a \u0110\u00f4ng v\u00e0 trong m\u00f9a h\u00e8, khi nhi\u1ec7t \u0111\u1ed9 kh\u00f4ng kh\u00ed l\u00ean cao, nh\u1eefng c\u01a1n m\u01b0a th\u01b0\u1eddng qu\u0103ng xu\u1ed1ng m\u1eb7t \u0111\u1ea5t v\u00f4 s\u1ed1 h\u1ea1t b\u0103ng h\u00ecnh c\u1ea9u, h\u00ecnh c\u00f4n v\u00e0 c\u00e1c h\u00ecnh d\u1ea1ng kh\u00e1c. Ng\u01b0\u1eddi ta g\u1ecdi ch\u00fang l\u00e0 m\u01b0a \u201c\u0111\u00e1\u201d. Trong khi m\u00f9a \u0110\u00f4ng, k\u1ec3 c\u1ea3 nh\u1eefng h\u00f4m gi\u00e1 r\u00e9t nh\u1ea5t c\u0169ng kh\u00f4ng bao gi\u1edd c\u00f3 m\u01b0a \u0111\u00e1. T\u1ea1i sao l\u1ea1i \u201cng\u01b0\u1ee3c \u0111\u1eddi\u201d th\u1ebf nh\u1ec9? Mu\u1ed1n hi\u1ec3u r\u00f5 v\u1ea5n \u0111\u1ec1 n\u00e0y, tr\u01b0\u1edbc ti\u00ean c\u1ea9n t\u00ecm hi\u1ec3u m\u01b0a \u0111\u00e1 \u0111\u01b0\u1ee3c h\u00ecnh th\u00e0nh nh\u01b0 th\u1ebf n\u00e0o. M\u01b0a \u0111\u00e1 v\u00e0 m\u01b0a r\u00e0o v\u1ed1n l\u00e0 anh em v\u1edbi nhau, \u0111\u1ec1u do v\u0169 t\u00edch sinh ra. Ch\u1ec9 kh\u00e1c nhau \u1edf ch\u1ed7 m\u01b0a \u0111\u00e3 h\u00ecnh th\u00e0nh trong \u0111i\u1ec1u ki\u1ec7n c\u00e1c d\u00f2ng kh\u00f4ng kh\u00ed l\u00ean xu\u1ed1ng (\u0111\u1ed1i l\u01b0u) r\u1ea5t m\u00e3nh li\u1ec7t. M\u00e0 \u0111i\u1ec1u ki\u1ec7n n\u00e0y ch\u1ec9 c\u00f3 \u0111\u01b0\u1ee3c v\u00e0o m\u00f9a n\u00f3ng, ch\u1ee9 r\u1ea5t \u00edt khi xu\u1ea5t hi\u1ec7n trong m\u00f9a l\u1ea1nh. V\u00e0o m\u00f9a n\u00f3ng \u1ea9m, n\u1eafng gay g\u1eaft, h\u00e0m l\u01b0\u1ee3ng h\u01a1i n\u01b0\u1edbc trong kh\u00f4ng kh\u00ed r\u1ea5t cao. Kh\u00ed quy\u1ec3n \u1edf t\u1ea9ng th\u1ea5p nh\u1eadn \u0111\u01b0\u1ee3c nhi\u1ec1u nhi\u1ec7t n\u0103ng s\u1ebd n\u00f3ng l\u00ean, h\u00ecnh th\u00e0nh c\u1ed9t kh\u00f4ng kh\u00ed d\u01b0\u1edbi n\u00f3ng tr\u00ean l\u1ea1nh, r\u1ea5t kh\u00f4ng \u1ed5n \u0111\u1ecbnh. L\u00fac n\u00e0y hi\u1ec7n t\u01b0\u1ee3ng \u0111\u1ed1i l\u01b0u m\u00e3nh li\u1ec7t ph\u00e1t sinh, t\u1ea1o ra nh\u1eefng \u0111\u00e1m m\u00e2y v\u0169 t\u00edch c\u00f3 kh\u1ea3 n\u0103ng g\u00e2y m\u01b0a \u0111\u00e1. \u0110\u1ed3ng th\u1eddi d\u00f2ng kh\u00ed \u0111i l\u00ean trong \u0111\u00e1m m\u00e2y c\u0169ng r\u1ea5t m\u1ea1nh, \u0111\u1ee7 \u0111\u1ec3 n\u00e2ng \u0111\u1ee1 nh\u1eefng h\u1ea1t b\u0103ng l\u1edbn h\u00ecnh th\u00e0nh v\u00e0 l\u1edbn d\u1ea9n l\u00ean trong m\u00e2y, khi\u1ebfn ch\u00fang ti\u1ebfp t\u1ee5c k\u1ebft h\u1ee3p v\u1edbi b\u00f4ng tuy\u1ebft hay gi\u1ecdt n\u01b0\u1edbc nh\u1ecf tr\u00ean \u0111\u01b0\u1eddng \u0111i, cu\u1ed1i c\u00f9ng tr\u1edf th\u00e0nh c\u1ee5c b\u0103ng c\u00f3 c\u1ea5u t\u1ea1o nhi\u1ec1u l\u1edbp trong v\u00e0 \u0111\u1ee5c xen k\u1ebd nhau. Khi c\u1ee5c b\u0103ng l\u1edbn t\u1edbi m\u1ed9t m\u1ee9c \u0111\u1ed9 m\u00e0 d\u00f2ng kh\u00ed \u0111i l\u00ean kh\u00f4ng c\u00f2n \u0111\u1ee7 s\u1ee9c n\u00e2ng \u0111\u1ee1 n\u1eefa th\u00ec s\u1ebd r\u01a1i xu\u1ed1ng \u0111\u1ea5t, g\u00e2y ra tr\u1eadn m\u01b0a \u0111\u00e1. M\u00f9a \u0110\u00f4ng, \u0111\u1ed1i l\u01b0u y\u1ebfu kh\u00f4ng t\u1ea1o b\u0103ng Sang \u0110\u00f4ng, do \u00e1nh n\u1eafng M\u1eb7t tr\u1eddi chi\u1ebfu xi\u00ean xu\u1ed1ng m\u1eb7t \u0111\u1ea5t n\u00ean nhi\u1ec7t l\u01b0\u1ee3ng thu \u0111\u01b0\u1ee3c \u1edf \u0111\u00e2y r\u1ea5t y\u1ebfu, kh\u00f4ng g\u00e2y ra s\u1ef1 \u0111\u1ed1i l\u01b0u m\u1ea1nh m\u1ebd. Trong khi \u0111\u00f3 kh\u00f4ng kh\u00ed l\u1ea1i kh\u00f4 hanh, n\u00ean d\u00f9 c\u00f3 \u0111\u1ed1i l\u01b0u ch\u0103ng n\u1eefa c\u0169ng kh\u00f4ng d\u1ec5 d\u00e0ng t\u1ea1o ra nh\u1eefng \u0111\u00e1m m\u00e2y c\u00f3 v\u0169","t\u00edch l\u1edbn. Th\u1eadm ch\u00ed n\u1ebfu m\u00e2y v\u0169 t\u00edch \u0111\u01b0\u1ee3c t\u1ea1o ra, nh\u01b0ng d\u00f2ng \u0111\u1ed1i l\u01b0u \u0111i l\u00ean trong n\u00f3 kh\u00f4ng \u0111\u1ee7 m\u1ea1nh c\u0169ng kh\u00f4ng duy tr\u00ec \u0111\u01b0\u1ee3c quan tr\u1ecdng h\u00ecnh th\u00e0nh v\u00e0 l\u1edbn l\u00ean c\u1ee7a h\u1ea1t b\u0103ng, v\u00ec th\u1ebf m\u00f9a gi\u00e1 l\u1ea1nh kh\u00f4ng c\u00f3 m\u01b0a \u0111\u00e1. C\u00f3 ng\u01b0\u1eddi s\u1ebd h\u1ecfi: \u201c\u0110i\u1ec1u ki\u1ec7n h\u00ecnh th\u00e0nh h\u1ea1t b\u0103ng \u0111\u00f2i h\u1ecfi nhi\u1ec7t \u0111\u1ed9 r\u1ea5t th\u1ea5p, trong khi m\u00f9a h\u00e8 l\u1ea1i r\u1ea5t n\u00f3ng, l\u00e0m sao c\u00f3 b\u0103ng \u0111\u01b0\u1ee3c?\u201d V\u1ea5n \u0111\u1ec1 l\u00e0 trong m\u00f9a h\u00e8 n\u00f3ng n\u1ef1c, nhi\u1ec7t \u0111\u1ed9 \u1edf d\u01b0\u1edbi \u0111\u1ea5t c\u00f3 th\u1ec3 l\u00ean t\u1edbi 30 \u0111\u1ed9 C, nh\u01b0ng kh\u00f4ng kh\u00ed c\u00e0ng l\u00ean cao l\u1ea1i c\u00e0ng l\u1ea1nh d\u1ea9n \u0111i. N\u1ebfu \u1edf d\u01b0\u1edbi \u0111\u00e1y \u0111\u00e1m m\u00e2y, nhi\u1ec7t \u0111\u1ed9 c\u00f2n 20 \u0111\u1ed9 C th\u00ec \u1edf trong \u0111\u00e1m m\u00e2y, ch\u1ed7 c\u00f3 \u0111\u1ed9 cao 4 km, nhi\u1ec7t \u0111\u1ed9 \u0111\u00e3 xu\u1ed1ng d\u01b0\u1edbi 0 \u0111\u1ed9 C. M\u1ed9t \u0111\u00e1m m\u00e2y m\u01b0a \u0111\u00e1 c\u00f3 th\u1ec3 v\u01b0\u01a1n t\u1edbi \u0111\u1ed9 cao tr\u00ean 10 km. V\u00ec v\u1eady, tr\u00ean kh\u00f4ng trung c\u00f3 nh\u1eefng v\u00f9ng nhi\u1ec7t \u0111\u1ed9 xu\u1ed1ng th\u1ea5p h\u01a1n \u0111i\u1ec3m \u0111\u00f3ng b\u0103ng, t\u1ea1o \u0111i\u1ec1u ki\u1ec7n cho nh\u1eefng h\u1ea1t b\u0103ng h\u00ecnh th\u00e0nh. T\u1ea1i sao khi tr\u1eddi s\u1eafp m\u01b0a m\u00e2y chuy\u1ec3n m\u00e0u x\u00e1m? Ch\u00ednh \u0111\u1ed9 d\u00e0y hay chi\u1ec1u cao c\u1ee7a \u0111\u00e1m m\u00e2y l\u00e0 nguy\u00ean nh\u00e2n khi\u1ebfn cho m\u00e2y c\u00f3 m\u00e0u x\u00e1m. Khi m\u00e2y m\u1ecfng, ch\u00fang s\u1ebd \u0111\u1ec3 cho ph\u1ea9n l\u1edbn \u00e1nh s\u00e1ng xuy\u00ean qua v\u00e0 c\u00f3 m\u00e0u tr\u1eafng. Nh\u01b0ng c\u0169ng nh\u01b0 nh\u1eefng v\u1eadt th\u1ec3 truy\u1ec1n \u00e1nh s\u00e1ng kh\u00e1c, m\u00e2y s\u1ebd tu\u00e2n theo quy lu\u1eadt c\u00e0ng d\u00e0y c\u00e0ng \u00edt \u00e1nh s\u00e1ng c\u00f3 th\u1ec3 xuy\u00ean qua. Tr\u01b0\u1edbc h\u1ebft ch\u00fang ta c\u1ea9n t\u00ecm hi\u1ec3u qua v\u1ec1 b\u1ea3n ch\u1ea5t c\u1ee7a m\u00e2y. M\u00e2y l\u00e0 t\u1eadp h\u1ee3p c\u1ee7a r\u1ea5t nhi\u1ec1u h\u1ea1t n\u01b0\u1edbc ho\u1eb7c tinh th\u1ec3 \u0111\u00e1 nh\u1ecf li ti, \u0111\u01b0\u1ee3c t\u1ea1o th\u00e0nh khi h\u01a1i n\u01b0\u1edbc ng\u01b0ng t\u1ee5 l\u1ea1i trong nh\u1eefng t\u00fai kh\u00f4ng kh\u00ed \u0111ang b\u1ed1c l\u00ean. Trong \u0111i\u1ec1u ki\u1ec7n th\u1eddi ti\u1ebft b\u00ecnh th\u01b0\u1eddng, kh\u00f4ng kh\u00ed ti\u1ebfp t\u1ee5c \u0111\u01b0\u1ee3c \u0111\u1ea9y l\u00ean khi\u1ebfn cho \u0111\u00e1m m\u00e2y \u0111\u01b0\u1ee3c b\u1ed3i \u0111\u1eafp th\u00eam. Nh\u1eefng h\u1ea1t n\u01b0\u1edbc v\u00e0 tinh th\u1ec3 \u0111\u00e1 nh\u1ecf x\u00edu n\u00e0y c\u00f3 k\u00edch c\u1ee1 nh\u1ecf v\u1eeba \u0111\u1ee7 \u0111\u1ec3 c\u00f3 th\u1ec3 ph\u00e2n t\u00e1n t\u1ea5t c\u1ea3 c\u00e1c m\u00e0u s\u1eafc c\u1ee7a \u00e1nh s\u00e1ng. Khi \u00e1nh s\u00e1ng \u0111\u01b0\u1ee3c h\u1ee3p th\u00e0nh t\u1eeb t\u1ea5t c\u1ea3 c\u00e1c m\u00e0u, n\u00f3 s\u1ebd \u0111\u01b0\u1ee3c m\u1eaft ch\u00fang ta c\u1ea3m nh\u1eadn l\u00e0 m\u00e0u tr\u1eafng. Khi m\u00e2y m\u1ecfng, ch\u00fang s\u1ebd \u0111\u1ec3 cho ph\u1ea9n l\u1edbn \u00e1nh s\u00e1ng xuy\u00ean qua v\u00e0 l\u00fac \u0111\u00f3 m\u00e2y c\u00f3 m\u00e0u tr\u1eafng. Khi \u0111\u1ed9 d\u00e0y c\u1ee7a \u0111\u00e1m m\u00e2y t\u0103ng l\u00ean, ph\u1ea9n \u0111\u00e1y c\u1ee7a \u0111\u00e1m m\u00e2y s\u1ebd c\u00f3 m\u00e0u t\u1ed1i h\u01a1n do \u00edt \u00e1nh s\u00e1ng xuy\u00ean qua, nh\u01b0ng v\u1eabn c\u00f3 th\u1ec3 ph\u00e2n t\u00e1n \u0111\u01b0\u1ee3c t\u1ea5t c\u1ea3 c\u00e1c m\u00e0u. B\u1eb1ng m\u1eaft th\u01b0\u1eddng ch\u00fang ta s\u1ebd nh\u00ecn th\u1ea5y \u0111\u00e1m m\u00e2y c\u00f3 m\u00e0u x\u00e1m v\u00e0 n\u1ebfu \u0111\u1ec3 \u00fd ta s\u1ebd th\u1ea5y ph\u1ea9n \u0111\u00e1y ph\u1eb3ng c\u1ee7a \u0111\u00e1m m\u00e2y lu\u00f4n c\u00f3 m\u00e0u s\u1eabm h\u01a1n so v\u1edbi m\u1eb7t b\u00ean. T\u1ea1i sao c\u1ea7u v\u1ed3ng l\u1ea1i tr\u00f2n v\u00e0 th\u01b0\u1eddng k\u00e9p? Nh\u1eefng c\u1ea9u v\u00f2ng th\u00f4ng th\u01b0\u1eddng nh\u1ea5t \u0111\u01b0\u1ee3c h\u00ecnh th\u00e0nh khi \u00e1nh s\u00e1ng M\u1eb7t tr\u1eddi chi\u1ebfu qua c\u00e1c h\u1ea1t m\u01b0a. C\u00e1c gi\u1ecdt m\u01b0a n\u00e0y c\u00f3 t\u00e1c d\u1ee5ng gi\u1ed1ng nh\u01b0 l\u0103ng k\u00ednh v\u00e0 t\u00e1n x\u1ea1 \u00e1nh s\u00e1ng M\u1eb7t tr\u1eddi th\u00e0nh quang ph\u1ed5 m\u00e0u s\u1eafc quen thu\u1ed9c: \u0111\u1ecf, cam, v\u00e0ng, xanh l\u1ee5c, xanh lam, ch\u00e0m, t\u00edm. C\u1ea9u v\u1ed3ng c\u00f3 h\u00ecnh tr\u00f2n do c\u00f3 li\u00ean quan \u0111\u1ebfn \u0111\u1eb7c t\u00ednh h\u00ecnh h\u1ecdc khi nh\u00ecn ch\u00fang. B\u1ea1n th\u1ea5y m\u1ed9t c\u00e1i c\u1ea9u v\u1ed3ng khi M\u1eb7t tr\u1eddi \u1edf ph\u00eda sau l\u01b0ng b\u1ea1n v\u00e0 c\u00e1c h\u1ea1t m\u01b0a th\u00ec \u1edf trong c\u00e1c \u0111\u00e1m m\u00e2y ph\u00eda tr\u01b0\u1edbc m\u1eb7t b\u1ea1n. C\u00e1c tia s\u00e1ng \u0111i qua tr\u00ean \u0111\u1ea9u b\u1ea1n t\u1eeb ph\u00eda sau, chi\u1ebfu v\u00e0o c\u00e1c h\u1ea1t m\u01b0a, b\u1ecb t\u00e1n x\u1ea1 th\u00e0nh m\u00e0u s\u1eafc, ph\u1ea3n x\u1ea1 ra ph\u00eda sau c\u00e1c h\u1ea1t m\u01b0a r\u1ed3i \u0111i v\u00e0o m\u1eaft","b\u1ea1n. M\u1eaft ph\u1ea3i ti\u1ebfp nh\u1eadn c\u00e1c tia s\u00e1ng chi\u1ebfu t\u1edbi t\u1eeb h\u1ea1t m\u01b0a theo m\u1ed9t g\u00f3c c\u1ee5 th\u1ec3 \u0111\u1ec3 c\u00f3 th\u1ec3 nh\u1eadn \u0111\u01b0\u1ee3c m\u00e0u s\u1eafc. M\u1ed9t c\u1ea9u v\u1ed3ng nh\u00ecn \u0111\u01b0\u1ee3c ch\u1ec9 \u0111\u01b0\u1ee3c h\u00ecnh th\u00e0nh n\u1ebfu c\u00e1c h\u1ea1t m\u01b0a n\u1eb1m \u0111\u00fang v\u1ecb tr\u00ed, nh\u1edd \u0111\u00f3 s\u1ebd c\u00f3 m\u1ed9t g\u00f3c nh\u1ea5t \u0111\u1ecbnh gi\u1eefa M\u1eb7t tr\u1eddi, gi\u1ecdt m\u01b0a v\u00e0 m\u1eaft b\u1ea1n. C\u00e1c g\u00f3c n\u00e0y ph\u1ea3i l\u00e0 g\u00f3c c\u1ed1 \u0111\u1ecbnh v\u00e0 c\u00e1c \u0111\u1eb7c t\u00ednh h\u00ecnh h\u1ecdc gi\u1eef cho g\u00f3c n\u00e0y kh\u00f4ng \u0111\u1ed5i c\u00f3 li\u00ean quan t\u1edbi m\u1ed9t \u0111\u01b0\u1eddng tr\u00f2n. B\u1ea1n ch\u1ec9 c\u00f3 th\u1ec3 nh\u00ecn th\u1ea5y m\u1ed9t ph\u1ea9n c\u1ee7a \u0111\u01b0\u1eddng tr\u00f2n n\u00e0y n\u1eb1m ph\u00eda tr\u00ean c\u1ee7a \u0111\u01b0\u1eddng ch\u00e2n tr\u1eddi. N\u1ebfu b\u1ea1n t\u01b0\u1edfng t\u01b0\u1ee3ng ph\u1ea9n c\u00f2n l\u1ea1i c\u1ee7a \u0111\u01b0\u1eddng tr\u00f2n n\u1eb1m \u1edf \u0111\u00e2u, b\u1ea1n s\u1ebd th\u1ea5y l\u00e0 b\u1ea1n c\u00f3 th\u1ec3 v\u1ebd m\u1ed9t \u0111\u01b0\u1eddng th\u1eb3ng t\u1eeb M\u1eb7t tr\u1eddi xuy\u00ean qua \u0111\u1ea9u b\u1ea1n \u0111\u1ebfn \u0111i\u1ec3m gi\u1eefa c\u1ee7a h\u00ecnh tr\u00f2n, m\u00e0 m\u1ed9t ph\u1ea9n c\u1ee7a n\u00f3 ch\u00ednh l\u00e0 c\u1ea9u v\u1ed3ng. \u0110i\u1ec1u n\u00e0y nghe c\u00f3 v\u1ebb thi v\u1ecb, nh\u01b0ng v\u1ec1 m\u1eb7t khoa h\u1ecdc, kh\u00f4ng c\u00f3 hai ng\u01b0\u1eddi n\u00e0o nh\u00ecn th\u1ea5y c\u00f9ng m\u1ed9t c\u1ea9u v\u1ed3ng. N\u1ebfu ba ng\u01b0\u1eddi c\u00f9ng nh\u00ecn v\u00e0o c\u1ea9u v\u1ed3ng, m\u1ed7i ng\u01b0\u1eddi \u0111\u1ec1u \u1edf m\u1ed9t g\u00f3c \u0111\u00fang \u0111\u1ec3 nh\u00ecn th\u1ea5y c\u1ea9u v\u1ed3ng \u0111\u00f3. \u0110\u00f4i khi ng\u01b0\u1eddi ta c\u00f2n nh\u00ecn th\u1ea5y m\u1ed9t c\u1ea9u v\u1ed3ng th\u1ee9 hai b\u00ean ngo\u00e0i c\u1ea9u v\u1ed3ng th\u1ee9 nh\u1ea5t, m\u1ed9t v\u00f2ng tr\u00f2n l\u1edbn h\u01a1n. M\u00e0u s\u1eafc \u1edf c\u1ea9u v\u1ed3ng th\u1ee9 hai n\u00e0y s\u1eafp x\u1ebfp ng\u01b0\u1ee3c l\u1ea1i, r\u1ea5t m\u1edd \u1ea3o m\u1ed9t c\u00e1ch kh\u00e1 \u0111\u1eb7c tr\u01b0ng. \u0110i\u1ec1u n\u00e0y x\u1ea3y ra ch\u00ednh l\u00e0 \u00e1nh s\u00e1ng \u0111i c\u00f9ng theo m\u1ed9t con \u0111\u01b0\u1eddng, nh\u01b0ng tia s\u00e1ng \u0111\u01b0\u1ee3c ph\u1ea3n x\u1ea1 l\u1ea1i hai l\u1ea9n trong gi\u1ecdt m\u01b0a. Hai l\u1ea9n ph\u1ea3n x\u1ea1 \u0111em l\u1ea1i hai hi\u1ec7u qu\u1ea3: tr\u1eadt t\u1ef1 m\u00e0u s\u1eafc b\u1ecb l\u1eadt ng\u01b0\u1ee3c v\u00e0 trong m\u1ed7i l\u1ea9n ph\u1ea3n x\u1ea1 \u00e1nh s\u00e1ng b\u1ecb y\u1ebfu \u0111i, ph\u00e2n t\u00e1n ra kh\u1ecfi h\u1ea1t m\u01b0a, l\u00e0m cho c\u1ea9u v\u1ed3ng th\u1ee9 hai m\u1edd \u1ea3o v\u00e0 \u00edt khi \u0111\u01b0\u1ee3c nh\u00ecn th\u1ea5y. \u0110\u1ec3 t\u1ef1 ki\u1ec3m ch\u1ee9ng, v\u00e0o l\u00fac th\u1eddi ti\u1ebft \u1ea5m, b\u1ea1n c\u00f3 th\u1ec3 t\u1ef1 t\u1ea1o ra m\u1ed9t c\u1ea9u v\u1ed3ng b\u1eb1ng \u1ed1ng t\u01b0\u1edbi n\u01b0\u1edbc \u0111\u1ec3 sao cho n\u01b0\u1edbc phun ra th\u1eadt \u0111\u1eb9p v\u00e0 M\u1eb7t tr\u1eddi n\u1eb1m \u0111\u00fang \u1edf ph\u00eda sau l\u01b0ng b\u1ea1n. V\u00ec sao b\u1ea7u tr\u1eddi xanh m\u00e0 kh\u00f4ng t\u00eda? M\u00e0u xanh l\u01a1 c\u1ee7a b\u1ea9u tr\u1eddi, c\u00e1c nh\u00e0 v\u1eadt l\u00fd gi\u1ea3i th\u00edch, l\u00e0 do c\u00e1c tia s\u00e1ng xanh b\u1ecb b\u1ebb cong \u0111i nhi\u1ec1u h\u01a1n tia s\u00e1ng \u0111\u1ecf. Nh\u01b0ng s\u1ef1 cong th\u00eam n\u00e0y -c\u00f2n g\u1ecdi l\u00e0 hi\u1ec7n t\u01b0\u1ee3ng t\u00e1n x\u1ea1 -c\u0169ng m\u1ea1nh kh\u00f4ng k\u00e9m \u1edf c\u00e1c tia t\u00edm, v\u1eady t\u1ea1i sao b\u1ea9u tr\u1eddi kh\u00f4ng ph\u1ea3i l\u00e0 m\u00e0u t\u00eda! C\u00e2u tr\u1ea3 l\u1eddi, \u0111\u01b0\u1ee3c gi\u1ea3i th\u00edch \u0111\u00f3 l\u00e0 do m\u1eaft c\u1ee7a ng\u01b0\u1eddi quan s\u00e1t. \u00c1nh s\u00e1ng tr\u1eafng \u0111\u01b0\u1ee3c t\u1ea1o th\u00e0nh t\u1eeb t\u1ea5t c\u1ea3 c\u00e1c m\u00e0u trong c\u1ea9u v\u1ed3ng. Khi \u00e1nh s\u00e1ng M\u1eb7t tr\u1eddi \u0111i v\u00e0o b\u1ea9u tr\u1eddi kh\u00ed quy\u1ec3n Tr\u00e1i \u0111\u1ea5t, g\u1eb7p ph\u1ea3i c\u00e1c ph\u00e2n t\u1eed nh\u1ecf nit\u01a1 v\u00e0 \u00f4xy tr\u00ean b\u1ea9u tr\u1eddi, n\u00f3 b\u1ecb t\u00e1n x\u1ea1, ho\u1eb7c kh\u00fac x\u1ea1. C\u00e1c tia s\u00e1ng c\u00f3 b\u01b0\u1edbc s\u00f3ng ng\u1eafn nh\u1ea5t (xanh v\u00e0 t\u00edm) b\u1ecb t\u00e1n x\u1ea1 m\u1ea1nh h\u01a1n c\u00e1c tia s\u00e1ng c\u00f3 b\u01b0\u1edbc s\u00f3ng d\u00e0i (\u0111\u1ecf v\u00e0 v\u00e0ng). V\u00ec th\u1ebf, khi ch\u00fang ta nh\u00ecn theo m\u1ed9t h\u01b0\u1edbng tr\u00ean b\u1ea9u tr\u1eddi, ch\u00fang ta nh\u00ecn th\u1ea5y nh\u1eefng b\u01b0\u1edbc s\u00f3ng b\u1ecb b\u1ebb cong nhi\u1ec1u nh\u1ea5t, th\u01b0\u1eddng l\u00e0 cu\u1ed1i d\u1ea3i m\u00e0u xanh. C\u00e1ch l\u00fd gi\u1ea3i truy\u1ec1n th\u1ed1ng v\u1ec1 b\u1ea9u tr\u1eddi xanh l\u00e0 \u00e1nh s\u00e1ng M\u1eb7t tr\u1eddi b\u1ecb t\u00e1n x\u1ea1 -c\u00e1c b\u01b0\u1edbc s\u00f3ng ng\u1eafn h\u01a1n th\u00ec t\u00e1n x\u1ea1 m\u1ea1nh h\u01a1n c\u00e1c tia s\u00f3ng d\u00e0i. Song th\u1ef1c t\u1ebf, m\u1ed9t n\u1eeda l\u1eddi gi\u1ea3i th\u00edch th\u01b0\u1eddng b\u1ecb b\u1ecf qua: \u0111\u00f3 l\u00e0 b\u1eb1ng c\u00e1ch n\u00e0o m\u0103t ch\u00fang ta nh\u1eadn \u0111\u01b0\u1ee3c ph\u1ed5 n\u00e0y.","M\u1eaft ng\u01b0\u1eddi nh\u00ecn \u0111\u01b0\u1ee3c m\u00e0u s\u1eafc l\u00e0 nh\u1edd v\u00e0o 3 lo\u1ea1i t\u1ebf b\u00e0o h\u00ecnh n\u00f3n tr\u00ean v\u00f5ng m\u1ea1c. M\u1ed7i lo\u1ea1i c\u1ea3m nh\u1eadn t\u01b0\u01a1ng \u1ee9ng v\u1edbi m\u1ed9t lo\u1ea1i \u00e1nh s\u00e1ng c\u00f3 b\u01b0\u1edbc s\u00f3ng kh\u00e1c nhau: d\u00e0i, v\u1eeba v\u00e0 ng\u1eafn. \u201cB\u1ea1n s\u1ebd c\u1ea9n c\u1ea3 ba lo\u1ea1i t\u1ebf b\u00e0o n\u00e0y m\u1edbi nh\u00ecn m\u00e0u ch\u00ednh x\u00e1c \u0111\u01b0\u1ee3c\u201d. Khi m\u1ed9t b\u01b0\u1edbc s\u00f3ng \u00e1nh s\u00e1ng \u0111i \u0111\u1ebfn m\u1eaft, t\u1ebf b\u00e0o h\u00ecnh n\u00f3n s\u1ebd g\u1eedi m\u1ed9t t\u00edn hi\u1ec7u t\u1edbi n\u00e3o. N\u1ebfu \u00e1nh s\u00e1ng xanh d\u01b0\u01a1ng v\u1edbi c\u00e1c g\u1ee3n s\u00f3ng ng\u1eafn, t\u1ebf b\u00e0o n\u00f3n s\u1ebd ph\u00e1t t\u00edn hi\u1ec7u \u0111\u1ec3 n\u00e3o nh\u00ecn ra m\u00e0u xanh. N\u1ebfu l\u00e0 s\u00f3ng \u0111\u1ecf v\u1edbi c\u00e1c b\u01b0\u1edbc s\u00f3ng d\u00e0i, n\u00e3o s\u1ebd nh\u00ecn th\u1ea5y m\u00e0u \u201c\u0111\u1ecf\u201d. Tuy nhi\u00ean c\u1ea3 ba lo\u1ea1i t\u1ebf b\u00e0o n\u00f3n tr\u00ean \u0111\u1ebfu nh\u1ea1y c\u1ea3m tr\u00ean m\u1ed9t kho\u1ea3ng r\u1ed9ng, c\u00f3 ch\u1ed7 ch\u1ed3ng ch\u1eadp l\u00ean nhau, \u0111i\u1ec1u \u0111\u00f3 c\u00f3 ngh\u0129a l\u00e0 hai ph\u1ed5 kh\u00e1c nhau c\u00f3 th\u1ec3 g\u00e2y ra c\u00f9ng m\u1ed9t ph\u1ea3n \u1ee9ng \u1edf m\u1ed9t nh\u00f3m c\u00e1c t\u1ebf b\u00e0o n\u00f3n. Ch\u1eb3ng h\u1ea1n n\u1ebfu m\u1ed9t s\u00f3ng \u0111\u1ecf v\u00e0 s\u00f3ng xanh l\u1ee5c \u0111i v\u00e0o m\u1eaft c\u00f9ng l\u00fac, c\u00e1c t\u1ebf b\u00e0o n\u00f3n kh\u00e1c nhau s\u1ebd g\u1eedi m\u1ed9t t\u00edn hi\u1ec7u m\u00e0 n\u00e3o d\u1ecbch ra l\u00e0 m\u00e0u v\u00e0ng. M\u00e0u c\u1ea9u v\u1ed3ng \u0111a s\u1eafc c\u1ee7a b\u1ea9u tr\u1eddi khi \u0111i v\u00e0o m\u1eaft ng\u01b0\u1eddi s\u1ebd \u0111\u01b0\u1ee3c c\u1ea3m nh\u1eadn t\u01b0\u01a1ng t\u1ef1 nh\u01b0 s\u1ef1 ch\u1ed3ng ch\u1eadp c\u1ee7a \u00e1nh s\u00e1ng xanh d\u01b0\u01a1ng \u201cnguy\u00ean ch\u1ea5t\u201d v\u1edbi \u00e1nh s\u00e1ng tr\u1eafng. V\u00e0 \u0111\u00f3 l\u00e0 l\u00fd do v\u00ec sao b\u1ea9u tr\u1eddi xanh l\u01a1 -ho\u1eb7c g\u1ea9n nh\u01b0 v\u1eady. M\u1eaft c\u1ee7a b\u1ea1n kh\u00f4ng th\u1ec3 ph\u00e2n bi\u1ec7t s\u1ef1 kh\u00e1c nhau gi\u1eefa ph\u1ed5 t\u1ed5ng h\u1ee3p xanh d\u01b0\u01a1ng t\u00edm v\u1edbi h\u1ed7n h\u1ee3p c\u1ee7a \u00e1nh s\u00e1ng xanh d\u01b0\u01a1ng nguy\u00ean ch\u1ea5t v\u00e0 \u00e1nh s\u00e1ng tr\u1eafng. Trong m\u1eaft c\u00e1c lo\u00e0i \u0111\u1ed9ng v\u1eadt kh\u00e1c, m\u00e0u c\u1ee7a b\u1ea9u tr\u1eddi l\u1ea1i kh\u00e1c h\u1eb3n. Tr\u1eeb ng\u01b0\u1eddi v\u00e0 m\u1ed9t s\u1ed1 lo\u00e0i linh tr\u01b0\u1edfng, h\u1ea9u h\u1ebft \u0111\u1ed9ng v\u1eadt ch\u1ec9 c\u00f3 hai lo\u1ea1i t\u1ebf b\u00e0o h\u00ecnh n\u00f3n thay v\u00ec ba. Ong m\u1eadt v\u00e0 m\u1ed9t s\u1ed1 lo\u00e0i chim nh\u00ecn \u1edf b\u01b0\u1edbc s\u00f3ng c\u1ef1c t\u00edm lo\u1ea1i b\u01b0\u1edbc s\u00f3ng v\u00f4 h\u00ecnh tr\u01b0\u1edbc con ng\u01b0\u1eddi. T\u1ea1i sao con ng\u01b0\u1eddi kh\u00f4ng b\u1ecb v\u0103ng ra kh\u1ecfi Tr\u00e1i \u0111\u1ea5t, khi Tr\u00e1i \u0111\u1ea5t quay? Khi xo\u00e1y nhanh c\u00e1i \u00f4 che m\u01b0a, nh\u1eefng gi\u1ecdt n\u01b0\u1edbc m\u01b0a s\u1ebd t\u1eeb xung quanh \u00f4 v\u0103ng ra. Tr\u00e1i \u0111\u1ea5t quay n\u00ean t\u1ea1i H\u00e0 N\u1ed9i m\u1ecdi v\u1eadt c\u0169ng quay v\u1edbi v\u1eadn t\u1ed1c 1.500 km\/ gi\u1edd hay 430 km \/ gi\u00e2y. Nh\u01b0ng ch\u1eb3ng nh\u1eefng m\u1ecdi v\u1eadt kh\u00f4ng b\u1ecb v\u0103ng ra m\u00e0 cho d\u00f9 c\u00f3 nh\u1ea3y l\u00ean cao v\u1eabn b\u1ecb r\u01a1i xu\u1ed1ng m\u1eb7t \u0111\u1ea5t ngay. S\u1ee9c h\u00fat c\u1ee7a Tr\u00e1i \u0111\u1ea5t l\u00e0 nguy\u00ean nh\u00e2n l\u00e0m cho ng\u01b0\u1eddi v\u00e0 c\u00e1c v\u1eadt xung quanh kh\u00f4ng th\u1ec3 v\u0103ng ra kh\u1ecfi Tr\u00e1i \u0111\u1ea5t. V\u1eadt th\u1ec3 mu\u1ed1n tho\u00e1t kh\u1ecfi s\u1ee9c h\u00fat c\u1ee7a Tr\u00e1i \u0111\u1ea5t \u0111\u1ec3 bay \u0111i th\u00ec c\u1ea9n ph\u1ea3i \u0111\u1ea1t \u0111\u01b0\u1ee3c t\u1ed1c \u0111\u1ed9 8 km\/ gi\u00e2y. Ph\u1ea3i ph\u00f3ng t\u00ean l\u1eeda v\u1edbi t\u1ed1c \u0111\u1ed9 g\u1ea9n 8 km \/ gi\u00e2y th\u00ec t\u00ean l\u1eeda kh\u00f4ng b\u1ecb r\u01a1i t\u1ea1i m\u1eb7t \u0111\u00e2t m\u00e0 chuy\u1ec3n \u0111\u1ed9ng theo qu\u1ef9 \u0111\u1ea1o v\u00f2ng tr\u00f2n quanh Tr\u00e1i \u0111\u1ea5t. V\u00ec v\u1eady mu\u1ed1n ph\u00f3ng v\u1ec7 tinh nh\u00e2n t\u1ea1o hay con t\u1ea9u v\u0169 tr\u1ee5 ph\u1ea3i c\u00f3 t\u00ean l\u1eeda \u0111\u1ea9y \u0111\u1ea1t \u0111\u01b0\u1ee3c t\u1ed1c \u0111\u1ed9 t\u1ed1i","thi\u1ec3u 8 km\/ gi\u00e2y th\u00ec v\u1ec7 tinh con t\u00e0u m\u1edbi chuy\u1ec3n \u0111\u1ed9ng quanh Tr\u00e1i \u0111\u1ea5t. Cho n\u00ean ng\u01b0\u1eddi ta g\u1ecdi t\u1ed1c \u0111\u1ed9 g\u1ea9n 8 km\/ gi\u00e2u l\u00e0 t\u1ed1c \u0111\u1ed9 v\u0169 tr\u1ee5 c\u1ea5p 1. L\u00e0m th\u1ebf n\u00e0o \u0111\u1ec3 bay kh\u1ecfi Tr\u00e1i \u0111\u1ea5t? Khi b\u1ea1n \u0111\u00e1 qu\u1ea3 b\u00f3ng hay b\u1eafn vi\u00ean \u0111\u1ea1n l\u00ean tr\u1eddi, d\u00f9 cao \u0111\u1ebfn \u0111\u00e2u, r\u1ed3i ch\u00fang c\u0169ng r\u01a1i xu\u1ed1ng \u0111\u1ea5t. T\u1ea1i sao ch\u00fang kh\u00f4ng l\u00ean cao m\u00e3i v\u00e0 \u201c\u0111i lu\u00f4n\u201d nh\u1ec9? \u0110\u01a1n gi\u1ea3n l\u00e0 t\u1ea5t c\u1ea3 c\u00e1c v\u1eadt th\u1ec3 quanh Tr\u00e1i \u0111\u1ea5t \u0111\u1ec1u kh\u00f4ng th\u1ec3 \u201cch\u1ea1y tr\u1ed1n\u201d kh\u1ecfi s\u1ee9c h\u00fat c\u1ee7a n\u00f3? V\u1eady m\u00e0 c\u00e1c v\u1ec7 tinh nh\u00e2n t\u1ea1o v\u00e0 phi thuy\u1ec1n kh\u00f4ng gian v\u1eabn c\u00f3 th\u1ec3 bay quanh Tr\u00e1i \u0111\u1ea5t r\u1ea5t nhi\u1ec1u ng\u00e0y m\u00e0 kh\u00f4ng b\u1ecb r\u01a1i? Mu\u1ed1n gi\u1ea3i th\u00edch \u0111i\u1ec1u n\u00e0y, tr\u01b0\u1edbc ti\u00ean ch\u00fang ta h\u00e3y l\u00e0m m\u1ed9t th\u00ed nghi\u1ec7m \u0111\u01a1n gi\u1ea3n: Bu\u1ed9c m\u1ed9t v\u1eadt n\u1eb7ng v\u00e0o \u0111\u1ea9u d\u00e2y, c\u1ea9m ch\u1eafc \u0111\u1ea9u kia s\u1ee3i d\u00e2y v\u00e0 quay m\u1ea1nh. Tay b\u1ea1n s\u1ebd c\u1ea3m th\u1ea5y c\u00f3 m\u1ed9t l\u1ef1c k\u00e9o c\u0103ng ra c\u00e1c ph\u00eda. T\u1ed1c \u0111\u1ed9 quay c\u00e0ng nhanh, l\u1ef1c k\u00e9o \u0111i ra c\u00e0ng m\u1ea1nh. L\u1ef1c k\u00e9o \u0111\u00f3 g\u1ecdi l\u00e0 l\u1ef1c ly t\u00e2m. M\u1ed9t l\u1ef1c kh\u00e1c c\u1ee7a s\u1ee3i d\u00e2y gi\u1eef ch\u1eb7t v\u1eadt n\u1eb7ng v\u00e0 b\u1eaft n\u00f3 quay tr\u00f2n, g\u1ecdi l\u00e0 l\u1ef1c h\u01b0\u1edbng t\u00e2m. L\u1ef1c ly t\u00e2m v\u00e0 l\u1ef1c h\u01b0\u1edbng t\u00e2m tuy ng\u01b0\u1ee3c nhau nh\u01b0ng c\u00e2n b\u1eb1ng v\u00e0 t\u00e1c \u0111\u1ed9ng v\u00e0o hai v\u1eadt th\u1ec3 (s\u1ee3i d\u00e2y v\u00e0 v\u1eadt n\u1eb7ng). M\u1ecdi v\u1eadt khi chuy\u1ec3n \u0111\u1ed9ng tr\u00f2n \u0111\u1ec1u b\u1ecb t\u00e1c \u0111\u1ed9ng c\u1ee7a l\u1ef1c h\u01b0\u1edbng t\u00e2m. 11,2 kmI gi\u00e2y m\u1edbi th\u1eafng s\u1ee9c h\u00fat Tr\u00e1i \u0111\u1ea5t Khi bay, v\u1ec7 tinh nh\u00e2n t\u1ea1o c\u0169ng ch\u1ecbu t\u00e1c d\u1ee5ng c\u1ee7a l\u1ef1c h\u01b0\u1edbng t\u00e2m c\u1ea9n thi\u1ebft kh\u00f4ng \u0111\u1ee7 l\u1edbn, th\u00ec s\u1ee9c h\u00fat n\u00e0y kh\u00f4ng nh\u1eefng bu\u1ed9c v\u1ec7 tinh nh\u00e2n t\u1ea1o ph\u1ea3i bay quanh m\u00e0 c\u00f2n k\u00e9o n\u00f3 tr\u1edf l\u1ea1i Tr\u00e1i \u0111\u1ea5t. Ch\u1ec9 khi v\u1ec7 tinh nh\u00e2n t\u1ea1o bay v\u1edbi t\u1ed1c \u0111\u1ed9 c\u1ef1c l\u1edbn, \u0111\u1ebfn m\u1ee9c l\u1ef1c h\u01b0\u1edbng t\u00e2m ho\u00e0n to\u00e0n d\u00f9ng v\u00e0o chuy\u1ec3n \u0111\u1ed9ng tr\u00f2n c\u1ee7a v\u1ec7 tinh th\u00ec n\u00f3 m\u1edbi kh\u00f4ng b\u1ecb r\u01a1i. Theo t\u00ednh to\u00e1n khoa h\u1ecdc, \u0111\u1ec3 kh\u1ea3 n\u0103ng n\u00e0y kh\u00f4ng x\u1ea3y ra, v\u1ec7 tinh nh\u00e2n t\u1ea1o ph\u1ea3i \u0111\u1ea1t t\u1ed1c \u0111\u1ed9 7,8 kmI gi\u00e2y v\u00e0 ph\u1ea3i bay theo h\u01b0\u1edbng n\u00e9m v\u0103ng ra kh\u1ecfi m\u1eb7t n\u01b0\u1edbc. T\u1ed1c \u0111\u1ed9 n\u00e0y \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 \u201ct\u1ed1c \u0111\u1ed9 v\u0169 tr\u1ee5 1\u201d. Tuy v\u1eady, ngay c\u1ea3 \u1edf t\u1ed1c \u0111\u1ed9 n\u00e0y, do g\u1eb7p ph\u1ea3i l\u1edbp kh\u00f4ng kh\u00ed m\u1ecfng ngo\u00e0i Tr\u00e1i \u0111\u1ea5t, v\u1ec7 tinh s\u1ebd chuy\u1ec3n \u0111\u1ed9ng ch\u1eadm d\u1ea9n v\u00e0 cu\u1ed1i c\u00f9ng r\u01a1i v\u00e0o t\u1ea9ng kh\u00ed quy\u1ec3n \u0111\u1eadm \u0111\u1eb7c, c\u1ecd s\u00e1t n\u00f3ng l\u00ean v\u00e0 b\u1ed1c ch\u00e1y. \u0110\u1ec3 kh\u1eafc ph\u1ee5c hi\u1ec7n t\u01b0\u1ee3ng \u0111\u00f3 v\u00e0 \u201ctho\u00e1t ly\u201d kh\u1ecfi Tr\u00e1i \u0111\u1ea5t, v\u1ec7 tinh ph\u1ea3i \u0111\u1ea1t t\u1ed1c \u0111\u1ed9 11,2 km \/ gi\u00e2y, khi \u0111\u00f3 n\u00f3 s\u1ebd tr\u1edf th\u00e0nh v\u1ec7 tinh nh\u00e2n t\u1ea1o. T\u1ed1c \u0111\u1ed9 n\u00e0y c\u00f2n g\u1ecdi l\u00e0 \u201ct\u1ed1c \u0111\u1ed9 tho\u00e1t ly\u201d ho\u1eb7c \u201ct\u1ed1c \u0111\u1ed9 v\u0169 tr\u1ee5 2\u201d. N\u1ebfu mu\u1ed1n bay t\u1edbi c\u00e1c h\u00e0nh tinh kh\u00e1c, v\u1ec7 tinh c\u1ea9n \u0111\u1ea1t t\u1ed1c \u0111\u1ed9 16,7 km\/gi\u00e2y. T\u1ed1c \u0111\u1ed9 n\u00e0y l\u00e0 \u201ct\u1ed1c \u0111\u1ed9 v\u0169 tr\u1ee5 3\u201d.","\u1ede \u0111\u00e2u c\u00e1c v\u1eadt n\u1eb7ng h\u01a1n? C\u00e0ng l\u00ean cao, l\u1ef1c Tr\u00e1i \u0111\u1ea5t h\u00fat c\u00e1c v\u1eadt c\u00e0ng gi\u1ea3m, v\u00ec th\u1ebf, ch\u00fang c\u00e0ng nh\u1eb9 \u0111i. N\u1ebfu v\u01b0\u1ee3t ra kh\u1ecfi b\u1ea9u kh\u00ed quy\u1ec3n c\u1ee7a Tr\u00e1i \u0111\u1ea5t, tr\u1ecdng l\u01b0\u1ee3ng c\u1ee7a v\u1eadt s\u1ebd b\u1eb1ng 0. Suy ng\u01b0\u1ee3c ra, b\u1ea1n c\u00f3 th\u1ec3 cho r\u1eb1ng c\u00e0ng v\u00e0o s\u00e2u trong l\u00f2ng \u0111\u1ea5t, v\u1eadt c\u00e0ng n\u1eb7ng h\u01a1n. Ch\u00fa \u00fd nh\u00e9, \u0111i\u1ec1u n\u00e0y ho\u00e0n to\u00e0n l\u00e0 ng\u1ed9 nh\u1eadn! Tr\u00e1i \u0111\u1ea5t h\u00fat nh\u1eefng v\u1eadt th\u1ec3 b\u00ean ngo\u00e0i y nh\u01b0 to\u00e0n b\u1ed9 kh\u1ed1i l\u01b0\u1ee3ng c\u1ee7a n\u00f3 t\u1eadp trung \u1edf t\u00e2m. Theo \u0111\u1ecbnh lu\u1eadt v\u1ea1n v\u1eadt h\u1ea5p d\u1eabn, l\u1ef1c h\u00fat gi\u1ea3m t\u1ef7 l\u1ec7 ngh\u1ecbch v\u1edbi b\u00ecnh ph\u01b0\u01a1ng kho\u1ea3ng c\u00e1ch, c\u00e0ng l\u00ean cao, l\u1ef1c h\u00fat c\u1ee7a Tr\u00e1i \u0111\u1ea5t l\u00ean c\u00e1c v\u1eadt c\u00e0ng y\u1ebfu \u0111i. N\u1ebfu \u0111\u01b0a qu\u1ea3 c\u00e2n 1 kg l\u00ean \u0111\u1ed9 cao 6.400 km,t\u1ee9c l\u00e0 d\u1eddi n\u00f3 ra xa t\u00e2m Tr\u00e1i \u0111\u1ea5t g\u1ea5p hai l\u1ea9n b\u00e1n k\u00ednh Tr\u00e1i \u0111\u1ea5t, th\u00ec l\u1ef1c h\u00fat s\u1ebd gi\u1ea3m \u0111i 2 m\u0169 2 l\u1ea9n, t\u1ee9c l\u00e0 4 l\u1ea9n, v\u00e0 qu\u1ea3 c\u00e2n treo v\u00e0o c\u00e2n l\u00f2 xo s\u1ebd ch\u1ec9 n\u1eb7ng c\u1ea3 th\u1ea3y 250 gram, ch\u1ee9 kh\u00f4ng ph\u1ea3i 1 kg. N\u1ebfu \u0111em qu\u1ea3 c\u00e2n \u0111i xa m\u1eb7t \u0111\u1ea5t 12.800 km, t\u1ee9c l\u00e0 xa t\u00e2m Tr\u00e1i \u0111\u1ea5t g\u1ea5p 3 l\u1ea9n, th\u00ec l\u1ef1c h\u00fat gi\u1ea3m \u0111i 9 l\u1ea9n, qu\u1ea3 c\u00e2n 1kg l\u00fac n\u00e0y ch\u1ec9 c\u00f2n n\u1eb7ng 111 g... T\u1eeb t\u00ednh to\u00e1n tr\u00ean, t\u1ea5t b\u1ea1n s\u1ebd n\u1ea3y ra \u00fd ki\u1ebfn cho r\u1eb1ng khi \u0111\u01b0a qu\u1ea3 c\u00e2n v\u00e0o s\u00e2u trong l\u00f2ng Tr\u00e1i \u0111\u1ea5t, t\u1ee9c l\u00e0 khi \u0111\u01b0a v\u1eadt ti\u1ebfn v\u1ec1 t\u00e2m, th\u00ec ta ph\u1ea3i th\u1ea5y s\u1ee9c h\u00fat t\u0103ng h\u01a1n, hay khi \u0111\u00f3 qu\u1ea3 c\u00e2n n\u1eb7ng h\u01a1n. Song, th\u1ef1c t\u1ebf, v\u1eadt th\u1ec3 kh\u00f4ng t\u0103ng tr\u1ecdng l\u01b0\u1ee3ng khi \u0111\u01b0a v\u00e0o s\u00e2u trong l\u00f2ng Tr\u00e1i \u0111\u1ea5t, m\u00e0 ng\u01b0\u1ee3c l\u1ea1i, nh\u1eb9 \u0111i. S\u1edf d\u0129 nh\u01b0 th\u1ebf l\u00e0 v\u00ec b\u00e2y gi\u1edd v\u1eadt th\u1ec3 kh\u00f4ng c\u00f2n ch\u1ecbu s\u1ee9c h\u00fat t\u1eeb m\u1ed9t ph\u00eda n\u1eefa, m\u00e0 l\u00e0 t\u1eeb nhi\u1ec1u ph\u00eda trong l\u00f2ng \u0111\u1ea5t (d\u01b0\u1edbi, tr\u00e1i, ph\u1ea3i.). R\u00fat c\u1ee5c, c\u00e1c l\u1ef1c h\u00fat c\u1ee7a qu\u1ea3 c\u1ea9u c\u00f3 b\u00e1n k\u00ednh b\u1eb1ng kho\u1ea3ng c\u00e1ch t\u1eeb t\u00e2m Tr\u00e1i \u0111\u1ea5t \u0111\u1ebfn ch\u1ed7 \u0111\u1eb7t \u0111\u1ed3 v\u1eadt l\u00e0 c\u00f3 gi\u00e1 tr\u1ecb. V\u00ec v\u1eady, c\u00e0ng \u0111i s\u00e2u v\u00e0o l\u00f2ng Tr\u00e1i \u0111\u1ea5t th\u00ec tr\u1ecdng l\u01b0\u1ee3ng c\u1ee7a v\u1eadt c\u00e0ng gi\u1ea3m nhanh. Khi t\u1edbi t\u00e2m Tr\u00e1i \u0111\u1ea5t, v\u1eadt tr\u1edf th\u00e0nh kh\u00f4ng tr\u1ecdng l\u01b0\u1ee3ng. Nh\u01b0 th\u1ebf, \u1edf tr\u00ean m\u1eb7t \u0111\u1ea5t, v\u1eadt s\u1ebd n\u1eb7ng h\u01a1n c\u1ea3 (1) (1) T\u00ecnh h\u00ecnh x\u1ea3y ra \u0111\u00fang nh\u01b0 th\u1ebf n\u1ebfu Tr\u00e1i \u0111\u1ea5t ho\u00e0n to\u00e0n \u0111\u1ed3ng nh\u1ea5t v\u1ec1 kh\u1ed1i l\u01b0\u1ee3ng ri\u00eang. Nh\u01b0ng tr\u00ean th\u1ef1c t\u1ebf, kh\u1ed1i l\u01b0\u1ee3ng ri\u00eang c\u1ee7a Tr\u00e1i \u0111\u1ea5t t\u0103ng l\u00ean khi v\u00e0o g\u1ea9n t\u00e2m: V\u00ec v\u1eady, khi v\u00e0o s\u00e2u trong l\u00f2ng Tr\u00e1i \u0111\u1ea5t th\u00ec tho\u1ea1t \u0111\u1ea9u tr\u1ecdng l\u1ef1c t\u0103ng l\u00ean m\u1ed9t kho\u1ea3ng n\u00e0o \u0111\u00f3, r\u1ed3i sau \u0111\u00f3 m\u1edbi b\u1eaft \u0111\u1ea9u gi\u1ea3m. V\u00ec sao ch\u00fang takh\u00f4ng c\u1ea3m th\u1ea5y Tr\u00e1i \u0111\u1ea5t chuy\u1ec3n \u0111\u1ed9ng? M\u1ed7i gi\u00e2y, Tr\u00e1i \u0111\u1ea5t v\u01b0\u1ee3t \u0111\u01b0\u1ee3c ch\u1eb7ng \u0111\u01b0\u1eddng t\u1edbi 30 kmquanh M\u1eb7t tr\u1eddi. \u0110\u00f3 l\u00e0 ch\u01b0a k\u1ec3 t\u1edbi vi\u1ec7c Tr\u00e1i \u0111\u1ea5t t\u1ef1 quay quanh m\u00ecnh v\u1edbi t\u1ed1c \u0111\u1ed9 \u1edf \u0111\u01b0\u1eddng x\u00edch \u0111\u1ea1o l\u00e0 465 m\u00e9t \/ gi\u00e2y. V\u1eady m\u00e0 c\u00f3 v\u1ebb nh\u01b0 Tr\u00e1i \u0111\u1ea5t \u0111ang \u0111\u1ee9ng y\u00ean, trong khi ch\u1ec9 c\u1ea9n ng\u1ed3i tr\u00ean xe, b\u1ea1n s\u1ebd th\u1ea5y xe lao \u0111i nhanh ch\u00f3ng m\u1eb7t. Tr\u1edf l\u1ea1i v\u1edbi m\u1ed9t t\u00ecnh hu\u1ed1ng th\u01b0\u1eddng g\u1eb7p: Khi \u0111i thuy\u1ec1n tr\u00ean s\u00f4ng, b\u1ea1n s\u1ebd th\u1ea5y","thuy\u1ec1n l\u01b0\u1edbt r\u1ea5t nhanh, c\u00e2y c\u1ed1i v\u00e0 m\u1ecdi v\u1eadt hai b\u00ean b\u1edd c\u1ee9 tr\u00f4i qua v\u00f9n v\u1ee5t. Nh\u01b0ng khi b\u1ea1n \u0111i t\u00e0u thu\u1ef7 tr\u00ean bi\u1ec3n r\u1ed9ng, tr\u01b0\u1edbc m\u1eaft b\u1ea1n l\u00e0 tr\u1eddi bi\u1ec3n xanh bi\u1ebfc m\u1ed9t m\u00e0u, nh\u1eefng con chimh\u1ea3i \u00e2u tr\u00f4ng xa nh\u01b0 m\u1ed9t \u0111\u1ed1m tr\u1eafng l\u01a1 l\u1eedng tr\u00ean kh\u00f4ng trung, l\u00fac \u0111\u00f3, b\u1ea1n s\u1ebd c\u1ea3m th\u1ea5y t\u00e0u thu\u1ef7 \u0111i qu\u00e1 ch\u1eadm, m\u1eb7c d\u00f9 t\u1ed1c \u0111\u1ed9 c\u1ee7a n\u00f3 h\u01a1n h\u1eb3n t\u1ed1c \u0111\u1ed9 c\u1ee7a thuy\u1ec1n tr\u00ean s\u00f4ng. V\u1ea5n \u0111\u1ec1 ch\u00ednh l\u00e0 \u1edf ch\u1ed7 \u0111\u00f3. Khi \u0111i thuy\u1ec1n, c\u00e2y c\u1ed1i hai b\u00ean b\u1edd s\u00f4ng kh\u00f4ng di chuy\u1ec3n m\u00e0 ch\u00ednh l\u00e0 thuy\u1ec1n di chuy\u1ec3n. N\u1ebfu c\u00e2y c\u1ed1i ven b\u1edd lao \u0111i c\u00e0ng nhanh, ch\u1ee9ng t\u1ecf t\u1ed1c \u0111\u1ed9 c\u1ee7a thuy\u1ec1n c\u00e0ng l\u1edbn. Nh\u01b0ng tr\u00ean bi\u1ec3n r\u1ed9ng kh\u00f4ng c\u00f3 g\u00ec l\u00e0m m\u1ed1c \u0111\u1ec3 ta th\u1ea5y t\u00e0u \u0111ang \u0111i nhanh. B\u1edfi th\u1ebf b\u1ea1n th\u1ea5y n\u00f3 l\u01b0\u1edbt \u0111i r\u1ea5t ch\u1eadm, th\u1eadm ch\u00ed c\u00f3 l\u00fac \u0111\u1ee9ng y\u00ean. Tr\u00e1i \u0111\u1ea5t nh\u01b0 m\u1ed9t chi\u1ebfc t\u00e0u kh\u1ed5ng l\u1ed3 trong kh\u00f4ng gian. N\u1ebfu b\u00ean c\u1ea1nh qu\u1ef9 \u0111\u1ea1o c\u1ee7a n\u00f3 c\u0169ng c\u00f3 nh\u1eefng v\u1eadt m\u1ed1c nh\u01b0 c\u00e2y c\u1ed1i b\u00ean b\u1edd s\u00f4ng, ch\u00fang ta s\u1ebd d\u1ec5 d\u00e0ng nh\u1eadn th\u1ea5y Tr\u00e1i \u0111\u1ea5t \u0111ang chuy\u1ec3n \u0111\u1ed9ng. Nh\u01b0ng \u1edf g\u1ea9n Tr\u00e1i \u0111\u1ea5t, ti\u1ebfc thay, l\u1ea1i kh\u00f4ng c\u00f3 v\u1eadt g\u00ec l\u00e0m chu\u1ea9n. Ch\u1ec9 c\u00f3 nh\u1eefng v\u00ec sao xa t\u00edt t\u1eafp gi\u00fap ta th\u1ea5y \u0111\u01b0\u1ee3c Tr\u00e1i \u0111\u1ea5t thay \u0111\u1ed5i v\u1ecb tr\u00ed theo ng\u00e0y, th\u00e1ng m\u00e0 th\u00f4i. C\u00e1c v\u00ec sao n\u00e0y \u1edf qu\u00e1 xa, n\u00ean trong m\u1ed9t th\u1eddi gian ng\u1eafn m\u1ea5y ph\u00fat, m\u1ea5y gi\u00e2y, ch\u00fang ta r\u1ea5t kh\u00f3 c\u1ea3m nh\u1eadn th\u1ea5y Tr\u00e1i \u0111\u1ea5t \u0111ang chuy\u1ec3n d\u1ecbch. C\u00f2 n v\u1ec1 vi\u1ec7c Tr\u00e1i \u0111\u1ea5t t\u1ef1 quay quanh n\u00f3 v\u1edbi t\u1ed1c \u0111\u1ed9 kh\u00e1 nhanh, ch\u00fang ta v\u00e0 m\u1ecdi v\u1eadt \u1edf tr\u00ean \u0111\u00f3 c\u0169ng \u0111ang quay v\u1edbi c\u00f9ng m\u1ed9t t\u1ed1c \u0111\u1ed9, b\u1edfi v\u1eady ch\u00fang ta kh\u00f4ng c\u1ea3m nh\u1eadn \u0111\u01b0\u1ee3c chuy\u1ec3n \u0111\u1ed9ng n\u00e0y. Nh\u01b0ng c\u00e1c b\u1ea1n ch\u1edb qu\u00ean r\u1eb1ng, h\u00e0ng ng\u00e0y, ch\u00fang ta nh\u00ecn th\u1ea5y M\u1eb7t tr\u1eddi, M\u1eb7t tr\u0103ng v\u00e0 c\u00e1c v\u00ec sao m\u1ecdc \u0111\u1eb1ng \u0110\u00f4ng v\u00e0 l\u1eb7n \u0111\u1eb1ng T\u00e2y, \u0111\u00f3 ch\u00ednh l\u00e0 k\u1ebft qu\u1ea3 c\u1ee7a vi\u1ec7c Tr\u00e1i \u0111\u1ea5t t\u1ef1 quay quanh m\u00ecnh n\u00f3. Tr\u00e1i \u0111\u1ea5t c\u00f3 th\u1ec3 ph\u00f3ng nhi\u1ec7t ra ngo\u00e0i \u0111\u01b0\u1ee3c kh\u00f4ng? Ng\u01b0\u1eddi ta th\u01b0\u1eddng d\u1ef1a v\u00e0o \u0111o nhi\u1ec7t \u0111\u1ed9 \u1edf gi\u1ebfng s\u00e2u \u0111\u1ec3 \u0111o nhi\u1ec7t \u0111\u1ed9 d\u01b0\u1edbi m\u1eb7t \u0111\u1ea5t, c\u1ee9 gi\u1ebfng s\u00e2u th\u00eam 100 mth\u00ec nhi\u1ec7t \u0111\u1ed9 t\u0103ng th\u00eam 3 \u0111\u1ed9 C. Ng\u01b0\u1eddi ta g\u1ecdi \u0111\u00f3 l\u00e0 thang \u0111\u1ecba nhi\u1ec7t. N\u1ebfu t\u00ednh theo c\u00f4ng th\u1ee9c oC I 100m ho\u1eb7c oC I 10m th\u00ec ta s\u1ebd t\u00ednh \u0111\u01b0\u1ee3c nhi\u1ec7t \u0111\u1ed9 trung t\u00e2m Tr\u00e1i \u0111\u1ea5t ph\u1ea3i g\u1ea9n 200.000 \u0111\u1ed9 C. Th\u1ebf nh\u01b0ng nhi\u1ec7t \u0111\u1ed9 th\u1ef1c t\u1ebf \u1edf trung t\u00e2m Tr\u00e1i \u0111\u1ea5t ch\u1ec9 kho\u1ea3ng 300 \u0111\u1ebfn 4.500 \u0111\u1ed9 C. Nhi\u1ec7t \u0111\u1ed9 Tr\u00e1i \u0111\u1ea5t l\u00e0 do c\u00e1c nguy\u00ean t\u1ed1 ph\u00f3ng x\u1ea1 c\u1ea5u t\u1ea1o n\u00ean Tr\u00e1i \u0111\u1ea5t g\u00e2y n\u00ean, nhi\u1ec7t \u0111\u1ed9 Tr\u00e1i \u0111\u1ea5t do c\u00e1c t\u1ea9ng nham th\u1ea1ch n\u00f3ng ch\u1ea3y mang l\u00ean Tr\u00e1i \u0111\u1ea5t. Nhi\u1ec7t \u0111\u1ed9 Tr\u00e1i \u0111\u1ea5t t\u00e1n x\u1ea1 ra ngo\u00e0i m\u1eb7t t\u00ednh theo 1 cm2 \u0111\u01a1n v\u1ecb PPm (lItri\u1ec7u) tr\u00ean 1 cm3I gy v\u00e0 nhi\u1ec7t l\u01b0\u1ee3ng t\u00e1n x\u1ea1 b\u00ecnh qu\u00e2n tr\u00ean to\u00e0n b\u1ec1 m\u1eb7t Tr\u00e1i \u0111\u1ea5t l\u00e0 1,4. \u1ede nh\u1eefng n\u01a1i c\u00f3 n\u00fai l\u1eeda ho\u1eb7c su\u1ed1i n\u01b0\u1edbc n\u00f3ng \u1edf \u0111\u00e1y bi\u1ec3n c\u0169ng ch\u1ec9 tr\u00ean d\u01b0\u1edbi 3. Nh\u01b0ng do Tr\u00e1i \u0111\u1ea5t h\u1ea5p th\u1ee5 nhi\u1ec7t t\u1eeb M\u1eb7t tr\u1eddi n\u00ean nhi\u1ec7t \u0111\u1ed9 xung quanh b\u1ec1 m\u1eb7t Tr\u00e1i \u0111\u1ea5t \u0111\u01b0\u1ee3c duy tr\u00ec. N\u1ebfu t\u00ednh l\u01b0\u1ee3ng nhi\u1ec7t c\u00e2n b\u1eb1ng m\u00e0 b\u1ec1 m\u1eb7t Tr\u00e1i \u0111\u1ea5t h\u1ea5p th\u1ee5 t\u1eeb M\u1eb7t tr\u1eddi v\u00e0 l\u01b0\u1ee3ng nhi\u1ec7t m\u00e0 Tr\u00e1i \u0111\u1ea5t b\u1ee9c x\u1ea1 ra ngo\u00e0i bi\u1ec3u th\u1ecb theo \u0111\u01a1n v\u1ecb v\u1eeba n\u00ean tr\u00ean ta s\u1ebd c\u00f3 con s\u1ed1 b\u00ecnh qu\u00e2n v\u01b0\u1ee3t qu\u00e1 8.000. T\u1eeb \u0111\u00f3 c\u00f3 th\u1ec3 th\u1ea5y \u0111\u01b0\u1ee3c nhi\u1ec7t l\u01b0\u1ee3ng do Tr\u00e1i \u0111\u1ea5t b\u1ee9c","x\u1ea1 so v\u1edbi l\u01b0\u1ee3ng nhi\u1ec7t m\u00e0 Tr\u00e1i \u0111\u1ea5t h\u1ea5p th\u1ee5 t\u1eeb M\u1eb7t tr\u1eddi l\u00e0 v\u00f4 c\u00f9ng b\u00e9. N\u00fai l\u1eeda l\u00e0 th\u1ee7 ph\u1ea1m g\u00e2y n\u00ean hi\u1ec7n t\u01b0\u1ee3ng El Nino? Trong m\u1ea5y n\u0103m v\u1eeba qua, hi\u1ec7n t\u01b0\u1ee3ng ElNino \u0111\u00e3 g\u00e2y ra x\u00e1o tr\u1ed9n nghi\u00eam tr\u1ecdng \u0111\u1ed1i v\u1edbi kh\u00ed h\u1eadt Tr\u00e1i \u0111\u1ea5t. M\u1edbi \u0111\u00e2y, gi\u1edbi khoa h\u1ecdc M\u1ef9 \u0111\u00e3 t\u00ecm ra th\u1ee7 ph\u1ea1m ch\u00ednh g\u00e2y n\u00ean ElNino: n\u00fai l\u1eeda. C\u00e1c nh\u00e0 khoa h\u1ecdc \u0111\u00e3 quan s\u00e1t c\u00e1c \u201cch\u1ec9 s\u1ed1 \u0111\u1ecba ch\u1ea5t\u201d -b\u1ee5i tr\u00ean l\u00f5i b\u0103ng c\u1ee7a 2 c\u1ef1c, v\u00f2ng c\u00e2y v\u00e0 s\u1ef1 ph\u00e1t tri\u1ec3n c\u1ee7a san h\u00f4 r\u1ed3i \u0111em so s\u00e1nh v\u1edbi c\u00e1c \u0111\u1ee3t phun tr\u00e0o n\u00fai l\u1eeda l\u1edbn t\u1eeb n\u0103m 1649 tr\u1edf l\u1ea1i \u0111\u00e2y. H\u1ecd nh\u1eadn th\u1ea5y r\u1eb1ng, ho\u1ea1t \u0111\u1ed9ng n\u00fai l\u1eeda d\u1eef d\u1ed9i \u1edf c\u00e1c v\u00f9ng nhi\u1ec7t \u0111\u1edbi s\u1ebd k\u00e9o theo nh\u1eefng \u0111\u1ee3t bi\u1ebfn \u0111\u1ed5i kh\u00ed h\u1eadu l\u1edbn, gi\u1ed1ng nh\u01b0 ElNino, trong nhi\u1ec1u n\u0103m li\u1ec1n. M\u1ed7i khi n\u00fai l\u1eeda phun tr\u00e0o, c\u00f3 nhi\u1ec1u kh\u1ea3 n\u0103ng l\u00e0 ElNino s\u1ebd xu\u1ea5t hi\u1ec7n v\u00e0o m\u00f9a \u0110\u00f4ng n\u0103m \u0111\u1ea5y. El Nino x\u1ea3y ra theo chu k\u1ef3 t\u1eeb 3 \u0111\u1ebfn 11 n\u0103m, khi nhi\u1ec7t \u0111\u1ed9 m\u1eb7t n\u01b0\u1edbc bi\u1ec3n t\u1ea1i khu v\u1ef1c ph\u00eda T\u00e2y Th\u00e1i B\u00ecnh D\u01b0\u01a1ng tr\u1edf n\u00ean \u1ea5m h\u01a1n so v\u1edbi b\u00ecnh th\u01b0\u1eddng. Gi\u00f3 m\u1eady d\u1ecbch th\u1ed5i t\u1eeb \u0110\u00f4ng sang T\u00e2y t\u1eaft h\u1eafn, khi\u1ebfn cho d\u00f2ng n\u01b0\u1edbc \u1edf khu v\u1ef1c n\u00e0y \u1ea5m l\u00ean. H\u1eadu qu\u1ea3 c\u1ee7a ElNino th\u1eadt kinh kh\u1ee7ng, \u1ea3nh h\u01b0\u1edfng \u0111\u1ebfn to\u00e0n b\u1ed9 nam b\u00e1n c\u1ea9u: l\u1edf tuy\u1ebft v\u00e0 l\u1edf \u0111\u1ea5t \u1edf Nam M\u1ef9, h\u1ea1n h\u00e1n \u1edf Nam Phi, l\u1ed1c xo\u00e1y nh\u1eb9 \u1edf \u0110\u1ea1i T\u00e2y D\u01b0\u01a1ng v\u00e0 ch\u00e1y r\u1eebng \u1edf Indonesia. Ngo\u00e0i ra, n\u00f3 c\u00f2n l\u00e0m cho m\u00f9a m\u00e0ng th\u1ea5t b\u00e1t, c\u1ea3n tr\u1edf \u0111\u01b0\u1eddng di c\u01b0 c\u1ee7a c\u00e1, g\u00e2y thi\u1ec7t h\u1ea1i nghi\u00eam tr\u1ecdng \u0111\u1ebfn \u0111\u1eddi s\u1ed1ng con ng\u01b0\u1eddi. N\u00fai l\u1eeda phun tr\u00e0o s\u1ebd th\u1ed5i m\u1ed9t l\u1edbp b\u1ee5i m\u1ecfng l\u00ean t\u1ea9ng b\u00ecnh l\u01b0u: ch\u00fang s\u1ebd l\u01a1 l\u1eedng \u1edf \u0111\u1ea5y, che b\u1edbt \u00e1nh n\u0103ng M\u1eb7t tr\u1eddi, khi\u1ebfn cho nhi\u1ec7t \u0111\u1ed9 Tr\u00e1i \u0111\u1ea5t gi\u1ea3m xu\u1ed1ng m\u1ed9t ch\u00fat. Tuy v\u1eady, khu v\u1ef1c Th\u00e1i B\u00ecnh D\u01b0\u01a1ng l\u1ea1i \u1ea5m l\u00ean do d\u00f2ng n\u01b0\u1edbc \u1ea5m t\u1eeb c\u00e1c n\u01a1i \u0111\u1ed5 v\u1ec1. S\u1ef1 bi\u1ebfn \u0111\u1ed5i v\u1ec1 nhi\u1ec7t \u0111\u1ed9 n\u00f3i tr\u00ean \u0111\u1ee7 \u0111\u1ec3 g\u00e2y n\u00ean m\u1ed9t \u0111\u1ee3t El Nino. ElNino th\u01b0\u1eddng k\u00e9o d\u00e0i su\u1ed1t 3 n\u0103m li\u1ec1n sau khi n\u00fai l\u1eeda phun tr\u00e0o d\u1eef d\u1ed9i. Tuy nhi\u00ean, c\u00e1c nh\u00e0 khoa h\u1ecdc c\u0169ng \u0111\u01b0a ra l\u1eddi c\u1ea3nh b\u00e1o: n\u00fai l\u1eeda kh\u00f4ng ph\u1ea3i l\u00e0 th\u1ee7 ph\u1ea1m duy nh\u1ea5t g\u00e2y n\u00ean hi\u1ec7n t\u01b0\u1ee3ng ElNino. Kh\u00ed h\u1eadu to\u00e0n c\u1ea9u \u1ea5m l\u00ean c\u00f2n do ch\u00ednh b\u00e0n tay con ng\u01b0\u1eddi. Ch\u00fang ta \u0111\u1ed1t ch\u00e1y nhi\u00ean li\u1ec7u kho\u00e1ng v\u00e0 th\u1ea3i ra kh\u00ed nh\u00e0 k\u00ednh. V\u00ec v\u1eady, ch\u00fang ta c\u1ea9n ph\u1ea3i gi\u1eef cho m\u00f4i tr\u01b0\u1eddng trong s\u1ea1ch, \u0111\u1ec3 kh\u00f4ng \u201c\u0111\u1ed5 th\u00eam d\u1ea9u v\u00e0o l\u1eeda\u201d khi ch\u01b0a c\u00f3 c\u00e1ch n\u00e0o ki\u1ec3m so\u00e1t \u0111\u01b0\u1ee3c n\u00fai l\u1eeda phun tr\u00e0o. Tr\u00e1i \u0111\u1ea5t t\u1ef1 quay m\u1ed9t v\u00f2ng c\u00f3 \u0111\u00fang m\u1ed9t ng\u00e0y kh\u00f4ng? Th\u1eddi gian Tr\u00e1i \u0111\u1ea5t t\u1ef1 quay m\u1ed9t v\u00f2ng l\u00e0 23 gi\u1edd 56 ph\u00fat, nh\u01b0ng m\u1ed9t ng\u00e0y tr\u00ean Tr\u00e1i \u0111\u1ea5t l\u1ea1i c\u00f3 t\u1edbi 24 gi\u1edd. \u0110\u00e2y ch\u1eb3ng ph\u1ea3i l\u00e0 m\u00e2u thu\u1eabn sao? M\u1ed9t ng\u00e0y trong cu\u1ed9c s\u1ed1ng th\u01b0\u1eddng nh\u1eadt c\u1ee7a ch\u00fang ta, ch\u00ednh l\u00e0 th\u1eddi gian lu\u00e2n chuy\u1ec3n ng\u00e0y \u0111\u00eam m\u1ed9t l\u1ea9n. D\u00f9ng ti\u00eau ch\u1ea9n g\u00ec \u0111\u1ec3 t\u00ednh m\u1ed9t c\u00e1ch ch\u00ednh x\u00e1c nh\u1ea5t s\u1ef1 d\u00e0i ng\u1eafn c\u1ee7a m\u1ed9t ng\u00e0y?","C\u00e1c nh\u00e0 thi\u00ean v\u0103n h\u1ecdc l\u1ef1a ch\u1ecdn M\u1eb7t tr\u1eddi qua tuy\u1ec1n T\u00ed Ng\u1ecd (\u0111\u01b0\u1eddng nam b\u1eafc), c\u0169ng ch\u00ednh l\u00e0 khi M\u1eb7t tr\u1eddi \u0111\u1ea1t \u0111\u1ebfn v\u1ecb tr\u00ed cao nh\u1ea5t so v\u1edbi m\u1eb7t \u0111\u1ea5t l\u00e0m ti\u00eau chu\u1ea9n t\u00ednh th\u1eddi gian. Th\u1eddi gian gi\u1eefa l\u1ea9n n\u00e0y M\u1eb7t tr\u1eddi \u0111i qua tuy\u1ebfn t\u00ed ng\u1ecd v\u00e0 l\u1ea9n ti\u1ebfp theo \u0111i qua c\u0169ng m\u1ed9t \u0111i\u1ec3m tr\u00ean tuy\u1ebfn T\u00ed Ng\u1ecd ch\u00ednh l\u00e0 m\u1ed9t ng\u00e0y, th\u1eddi gian trung gian c\u1ea9n thi\u1ebft l\u00e0 24 gi\u1edd. N\u1ebfu Tr\u00e1i \u0111\u1ea5t ch\u1ec9 t\u1ef1 quay m\u00e0 kh\u00f4ng quay xung quanh c\u00e1c thi\u00ean th\u1ec3, nh\u01b0 v\u1eady, do s\u1ef1 t\u1ef1 quay c\u1ee7a Tr\u00e1i \u0111\u1ea5t, th\u1eddi gian M\u1eb7t tr\u1eddi \u0111i qua tuy\u1ebfn T\u00ed Ng\u1ecd hai l\u1ea9n, ch\u00ednh l\u00e0 th\u1eddi gian Tr\u00e1i \u0111\u1ea5t t\u1ef1 quay m\u1ed9t v\u00f2ng. Tr\u00ean th\u1ef1c t\u1ebf, khi Tr\u00e1i \u0111\u1ea5t t\u1ef1 quay c\u0169ng \u0111\u1ed3ng th\u1eddi quay xung quanh M\u1eb7t tr\u1eddi. Sau khi Tr\u00e1i \u0111\u1ea5t t\u1ef1 quay m\u1ed9t v\u00f2ng, do nguy\u00ean nh\u00e2n c\u1ee7a vi\u1ec7c quay xung quanh thi\u00ean th\u1ec3, Tr\u00e1i \u0111\u1ea5t s\u1ebd kh\u00f4ng \u1edf ch\u1ed7 c\u0169 n\u1eefa, m\u00e0 di chuy\u1ec3n t\u1eeb \u0111i\u1ec3m th\u1ee9 nh\u1ea5t \u0111\u1ebf \u0111i\u1ec3m th\u1ee9 hai tr\u00ean b\u1ea3n \u0111\u1ed3. \u0110i\u1ec3m m\u00e0 l\u1ea9n \u0111\u1ea9u ti\u00ean h\u01b0\u1edbng v\u1ec1 ph\u00eda M\u1eb7t tr\u1eddi, sau khi Tr\u00e1i \u0111\u1ea5t t\u1ef1 quay m\u1ed9t v\u00f2ng v\u1eabn ch\u01b0a h\u01b0\u1edbng v\u1ec1 ph\u00eda M\u1eb7t tr\u1eddi l\u1ea9n ti\u1ebfp theo (m\u0169i t\u00ean m\u00e0u \u0111en tr\u00ean b\u1ea3n \u0111\u1ed3 \u0111\u1ec3 ch\u1ec9 h\u01b0\u1edbng), c\u1ea9n ph\u1ea3i \u0111\u1ee3i Tr\u00e1i \u0111\u1ea5t quay th\u00eam m\u1ed9t g\u00f3c \u0111\u1ed9 nh\u1ecf n\u1eefa m\u1edbi h\u01b0\u1edbng v\u1ec1 ph\u00eda M\u1eb7t tr\u1eddi. (M\u0169i t\u00ean m\u00e0u x\u00e1m tr\u00ean b\u1ea3n \u0111\u1ed3 ch\u1ec9 ph\u01b0\u01a1ng h\u01b0\u1edbng). Th\u1eddi gian Tr\u00e1i \u0111\u1ea5t t\u1ef1 quay quanh g\u00f3c \u0111\u1ed9 n\u00e0y, c\u1ea9n kho\u1ea3ng 4 ph\u00fat. Trong th\u1eddi gian hai l\u1ea9n M\u1eb7t tr\u1eddi \u0111i qua tuy\u1ebfn T\u00ed Ng\u1ecd, th\u1ef1c t\u1ebf Tr\u00e1i \u0111\u1ea5t ch\u1ec9 quay \u0111\u01b0\u1ee3c h\u01a1n m\u1ed9t v\u00f2ng m\u1ed9t ch\u00fat. Qu\u00e3ng th\u1eddi gian n\u00e0y m\u1edbi l\u00e0 m\u1ed9t ng\u00e0y 24 gi\u1edd, trong cu\u1ed9c s\u1ed1ng c\u1ee7a ch\u00fang ta. Nh\u01b0 v\u1eady, sau khi Tr\u00e1i \u0111\u1ea5t quay m\u1ed9t v\u00f2ng xung quanh M\u1eb7t tr\u1eddi, th\u00ec th\u1ef1c t\u1ebf s\u1ed1 v\u00f2ng Tr\u00e1i \u0111\u1ea5t t\u1ef1 quay nhi\u1ec1u h\u01a1n s\u1ed1 ng\u00e0y trong m\u1ed9t n\u0103m l\u00e0 m\u1ed9t l\u1ea9n. T\u1ea1i sao Tr\u00e1i\u0111\u1ea5t c\u00f3th\u1ec3 t\u1ef1 quay xung quanh tr\u1ee5c? Tr\u00e1i \u0111\u1ea5t c\u0169ng gi\u1ed1ng nh\u01b0 8 h\u00e0nh tinh l\u1edbn kh\u00e1c trong h\u1ec7 M\u1eb7t tr\u1eddi, \u0111\u1ed3ng th\u1eddi v\u1edbi vi\u1ec7c quay xung quanh M\u1eb7t tr\u1eddi, n\u00f3 c\u0169ng chuy\u1ec3n \u0111\u1ed9ng kh\u00f4ng ng\u1eebng quanh tr\u1ee5c quay gi\u1ea3 t\u01b0\u1edfng. Hi\u1ec7n t\u01b0\u1ee3ng lu\u00e2n chuy\u1ec3n ng\u00e0y \u0111\u00eam l\u00e0 do Tr\u00e1i \u0111\u1ea5t t\u1ef1 quay t\u1ea1o n\u00ean. M\u1ea5y tr\u0103m n\u0103m tr\u01b0\u1edbc, con ng\u01b0\u1eddi \u0111\u00e3 \u0111\u01b0a ra r\u1ea5t nhi\u1ec1u ph\u01b0\u01a1ng ph\u00e1p ch\u1ee9ng minh Tr\u00e1i \u0111\u1ea5t t\u1ef1 quay, \u201cqu\u1ea3 l\u1eafc Phu-c\u00f4n\u201d n\u1ed5i ti\u1ebfng \u0111\u00e3 cho ch\u00fang ta nh\u00ecn th\u1ea5y m\u1ed9t c\u00e1ch ch\u00ednh x\u00e1c s\u1ef1 t\u1ef1 quay c\u1ee7a Tr\u00e1i \u0111\u1ea5t. Nh\u01b0ng t\u1ea1i sao Tr\u00e1i \u0111\u1ea5t c\u00f3 th\u1ebb t\u1ef1 quay xung quanh tr\u1ee5c? V\u00e0 t\u1ea1i sao Tr\u00e1i \u0111\u1ea5t c\u00f3 th\u1ec3 quay xung quanh M\u1eb7t tr\u1eddi? \u0110\u00e2y l\u00e0 m\u1ed9t v\u1ea5n \u0111\u1ec1 l\u00e0m cho c\u00e1c nh\u00e0 khoa h\u1ecdc c\u1ea3m th\u1ea5y r\u1ea5t h\u1ee9ng th\u00fa trong nhi\u1ec1u n\u0103m li\u1ec1n. Xem x\u00e9t s\u01a1 l\u01b0\u1ee3c th\u00ec s\u1ef1 quay l\u00e0 m\u1ed9t h\u00ecnh th\u1ee9c v\u1eadn \u0111\u1ed9ng c\u01a1 b\u1ea3n c\u1ee7a nhi\u1ec1u thi\u00ean th\u1ec3 trong v\u0169 tr\u1ee5, nh\u01b0ng \u0111\u1ec3 tr\u1ea3 l\u1eddi v\u1ea5n \u0111\u1ec1 n\u00e0y m\u1ed9t c\u00e1ch ch\u00ednh x\u00e1c, tr\u01b0\u1edbc ti\u00ean c\u00f2n c\u1ea9n ph\u1ea3i l\u00e0m r\u00f5 Tr\u00e1i \u0111\u1ea5t v\u00e0 h\u1ec7 M\u1eb7t tr\u1eddi h\u00ecnh th\u00e0nh nh\u01b0 th\u1ebf n\u00e0o. S\u1ef1 kh\u00e1m ph\u00e1 ra hi\u1ec7n t\u01b0\u1ee3ng t\u1ef1 quay v\u00e0 hi\u1ec7n t\u01b0\u1ee3ng quay xung","quanh c\u1ee7a Tr\u00e1i \u0111\u1ea5t c\u00f3 m\u1ed1i t\u01b0\u01a1ng quan m\u1eadt thi\u1ebft \u0111\u1ebfn s\u1ef1 h\u00ecnh th\u00e0nh h\u1ec7 M\u1eb7t tr\u1eddi. Nh\u1eefng l\u00ed lu\u1eadn v\u1ec1 thi\u00ean v\u0103n h\u1ecdc hi\u1ec7n \u0111\u1ea1i cho r\u1eb1ng, h\u1ec7 M\u1eb7t tr\u1eddi \u0111\u01b0\u1ee3c h\u00ecnh th\u00e0nh t\u1eeb c\u00e1i g\u1ecdi l\u00e0 Tinh v\u00e2n nguy\u00ean thu\u1ef7. Tinh v\u00e2n nguy\u00ean thu\u1ef7 l\u00e0 m\u1ed9t m\u1ea3ng m\u00e2y kh\u00ed l\u1edbn v\u00e0 r\u1ea5t lo\u00e3ng, 5 t\u1ec9 n\u0103m tr\u01b0\u1edbc \u0111\u00e3 ch\u1ecbu \u1ea3nh h\u01b0\u1edfng r\u1ed1i lo\u1ea1n v\u00e0 co l\u1ea1i ph\u00eda trung t\u00e2m d\u01b0\u1edbi t\u00e1c \u0111\u1ed9ng c\u1ee7a l\u1ef1c h\u1ea5p d\u1eabn. Tr\u1ea3i qua th\u1eddi gian bi\u1ebfn \u0111\u1ed5i d\u00e0i \u0111\u1eb1ng \u0111\u1eb5ng, m\u1eadt \u0111\u1ed9 v\u1eadt ch\u1ea5t c\u1ee7a b\u1ed9 ph\u1eadn trung t\u00e2m ng\u00e0y c\u00e0ng l\u1edbn, nhi\u1ec7t \u0111\u1ed9 c\u0169ng cao h\u01a1n, cu\u1ed1i c\u00f9ng \u0111\u1ea1t \u0111\u1ebfn m\u1ee9c \u0111\u1ed9 c\u00f3 th\u1ec3 d\u1eabn \u0111\u1ebfn ph\u1ea3n \u1ee9ng nhi\u1ec7t h\u1ea1ch v\u00e0 chuy\u1ec3n ho\u00e1 th\u00e0nh M\u1eb7t tr\u1eddi. Th\u1ec3 kh\u00ed c\u00f2n s\u00f3t l\u1ea1i xung quanh M\u1eb7t tr\u1eddi d\u1ea9n d\u1ea9n h\u00ecnh th\u00e0nh m\u1ed9t l\u1edbp th\u1ec3 kh\u00ed xoay tr\u00f2n h\u00ecnh c\u00e1i ch\u1eadu, tr\u1ea3i qua qu\u00e1 tr\u00ecnh co l\u1ea1i, l\u1ea1i va \u0111\u1eadp, t\u00edch t\u1ee5, l\u1edbp th\u1ec3 kh\u00ed n\u00e0y t\u1eebng b\u01b0\u1edbc t\u00edch t\u1ee5 th\u00e0nh c\u00e1c h\u00f2n ch\u1ea5t r\u1eafn, h\u00e0nh tinh nh\u1ecf, h\u00e0nh tinh nguy\u00ean thu\u1ef7, cu\u1ed1i c\u00f9ng h\u00ecnh th\u00e0nh c\u00e1c thi\u00ean th\u1ec3 trong h\u1ec7 M\u1eb7t tr\u1eddi nh\u01b0 c\u00e1c ti\u1ec3u h\u00e0nh tinh v\u00e0 \u0111\u1ea1i h\u00e0nh tinh \u0111\u1ed9c l\u1eadp. Ch\u00fang ta bi\u1ebft r\u1eb1ng, c\u1ea9n \u0111o \u0111\u1ed9 chuy\u1ec3n \u0111\u1ed9ng nhanh ch\u1eadm c\u1ee7a v\u1eadt th\u1ec3 theo \u0111\u01b0\u1eddng th\u1eb3ng, c\u00f3 th\u1ec3 d\u00f9ng t\u1ed1c \u0111\u1ed9 \u0111\u1ec3 bi\u1ec3u th\u1ecb, v\u1eady th\u00ec d\u00f9ng c\u00e1i g\u00ec \u0111\u1ec3 \u0111o l\u01b0\u1eddng tr\u1ea1ng th\u00e1i quay tr\u00f2n c\u1ee7a v\u1eadt th\u1ec3? C\u00f3 m\u1ed9t c\u00e1ch l\u00e0 d\u00f9ng \u201cl\u01b0\u1ee3ng chuy\u1ec3n \u0111\u1ed9ng g\u00f3c\u201d. \u0110\u1ed1i v\u1edbi m\u1ed9t v\u1eadt th\u1ec3 chuy\u1ec3n \u0111\u1ed9ng xung quanh m\u1ed9t \u0111i\u1ec3m c\u1ed1 \u0111\u1ecbnh th\u00ec l\u01b0\u1ee3ng chuy\u1ec3n \u0111\u1ed9ng g\u00f3c c\u1ee7a n\u00f3 b\u1eb1ng ch\u1ea5t l\u01b0\u1ee3ng nh\u00e2n v\u1edbi t\u1ed1c \u0111\u1ed9 v\u00e0 nh\u00e2n ti\u1ebfp v\u1edbi kho\u1ea3ng c\u00e1ch gi\u1eefa v\u1eadt th\u1ec3 n\u00e0y v\u00e0 \u0111i\u1ec3m c\u1ed1 \u0111\u1ecbnh. Trong v\u1eadt l\u00fd h\u1ecdc c\u00f3 \u0111\u1ecbnh lu\u1eadt b\u1ea3o t\u1ed3n l\u01b0\u1ee3ng chuy\u1ec3n \u0111\u1ed9ng g\u00f3c r\u1ea5t quan tr\u1ecdng, \u0111\u00f3 l\u00e0: M\u1ed9t v\u1eadt th\u1ec3 chuy\u1ec3n \u0111\u1ed9ng, n\u1ebfu kh\u00f4ng ch\u1ecbu t\u00e1c \u0111\u1ed9ng c\u1ee7a ngo\u1ea1i l\u1ef1c th\u00ec l\u01b0\u1ee3ng chuy\u1ec3n \u0111\u1ed9ng c\u1ee7a g\u00f3c c\u1ee7a n\u00f3 s\u1ebd kh\u00f4ng bi\u1ebfn \u0111\u1ed5i theo s\u1ef1 bi\u1ebfn \u0111\u1ed5i h\u00ecnh d\u1ea1ng c\u1ee7a v\u1eadt th\u1ec3. V\u00ed d\u1ee5: m\u1ed9t di\u1ec5n vi\u00ean m\u00faa Bal\u00ea, khi \u0111ang quay \u0111\u1ed9t nhi\u00ean thu c\u00e1nh tay l\u1ea1i (kho\u1ea3ng c\u00e1ch gi\u1eefa t\u00e2m v\u00e0 \u0111i\u1ec3m c\u1ed1 \u0111\u1ecbnh nh\u1ecf \u0111i) th\u00ec t\u1ed1c \u0111\u1ed9 quay c\u1ee7a ng\u01b0\u1eddi \u0111\u00f3 s\u1ebd nhanh h\u01a1n, b\u1edfi v\u00ec ch\u1ec9 c\u00f3 v\u1eady m\u1edbi c\u00f3 th\u1ec3 b\u1ea3o \u0111\u1ea3m vai tr\u00f2 quan tr\u1ecdng trong vi\u1ec7c n\u1ea3y sinh t\u1ed1c \u0111\u1ed9 t\u1ef1 quay c\u1ee7a Tr\u00e1i \u0111\u1ea5t. Th\u00ec ra vi\u1ec7c h\u00ecnh th\u00e0nh tinh v\u00e2n nguy\u00ean thu\u1ef7 c\u1ee7a h\u1ec7 M\u1eb7t tr\u1eddi \u0111\u00e3 c\u00f3 k\u00e8m theo l\u01b0\u1ee3ng chuy\u1ec3n \u0111\u1ed9ng g\u00f3c. Sau khi h\u00ecnh th\u00e0nh h\u1ec7 th\u1ed1ng M\u1eb7t tr\u1eddi v\u00e0 h\u00e0nh tinh, l\u01b0\u1ee3ng chuy\u1ec3n \u0111\u1ed9ng g\u00f3c c\u1ee7a n\u00f3 kh\u00f4ng b\u1ecb gi\u1ea3m \u0111i, nh\u01b0ng s\u1ebd c\u00f3 s\u1ef1 ph\u00e2n b\u1ed5 l\u1ea1i, trong quan tr\u1ecdng t\u00edch t\u1ee5 v\u1eadt ch\u1ea5t l\u00e2u d\u00e0i, c\u00e1c thi\u00ean th\u1ec3 l\u1ea9n l\u01b0\u1ee3t \u0111\u1ea1t \u0111\u1ebfn l\u01b0\u1ee3ng chuy\u1ec3n \u0111\u1ed9ng g\u00f3c nh\u1ea5t \u0111\u1ecbnh t\u1eeb trong c\u00e1c tinh v\u00e2n nguy\u00ean thu\u1ef7. Do l\u01b0\u1ee3ng chuy\u1ec3n \u0111\u1ed9ng g\u00f3c \u0111\u01b0\u1ee3c gi\u1eef c\u1ed1 \u0111\u1ecbnh, trong quan tr\u1ecdng co l\u1ea1i, t\u1ed1c \u0111\u1ed9 quay c\u1ee7a c\u00e1c h\u00e0nh tinh c\u0169ng s\u1ebd t\u0103ng l\u00ean ng\u00e0y c\u00e0ng nhanh. Tr\u00e1i \u0111\u1ea5t c\u0169ng kh\u00f4ng l\u00e0 ngo\u1ea1i l\u1ec7, l\u01b0\u1ee3ng chuy\u1ec3n \u0111\u1ed9ng g\u00f3c m\u00e0 n\u00f3 \u0111\u1ea1t \u0111\u01b0\u1ee3c ph\u00e2n b\u1ed1 ch\u1ee7 y\u1ebfu trong vi\u1ec7c Tr\u00e1i \u0111\u1ea5t quay quanh M\u1eb7t tr\u1eddi, Tr\u00e1i \u0111\u1ea5t quay quanh M\u1eb7t tr\u0103ng v\u00e0 Tr\u00e1i \u0111\u1ea5t t\u1ef1 chuy\u1ec3n \u0111\u1ed9ng, nh\u01b0ng c\u1ea9n ph\u00e2n t\u00edch ch\u00ednh x\u00e1c s\u1ef1 chuy\u1ec3n \u0111\u1ed9ng c\u1ee7a Tr\u00e1i \u0111\u1ea5t xung quanh c\u00e1c h\u00e0nh tinh l\u1edbn v\u00e0 s\u1ef1 t\u1ef1 v\u1eadn \u0111\u1ed9ng c\u1ee7a Tr\u00e1i \u0111\u1ea5t, c\u0169ng c\u1ea9n s\u1ef1 c\u1ed1 g\u1eafng trong c\u00f4ng t\u00e1c nghi\u00ean c\u1ee9u c\u1ee7a c\u00e1c nh\u00e0 khoa h\u1ecdc ng\u00e0y nay. V\u00ec sao Tr\u00e1i \u0111\u1ea5t l\u1ea1i n\u00f3ng l\u00ean? Trong cu\u1ed9c s\u1ed1ng c\u1ee7a lo\u00e0i ng\u01b0\u1eddi, \u0111\u1eb7c bi\u1ec7t l\u00e0 trong s\u1ea3n xu\u1ea5t c\u00f4ng nghi\u1ec7p, d\u1ea9u v\u00e0 than \u0111\u00e1 \u0111\u01b0\u1ee3c d\u00f9ng r\u1ea5t nhi\u1ec1u, do \u0111\u00f3 \u0111\u00e3 th\u1ea3i v\u00e0o kh\u00f4ng kh\u00ed tr\u00ean cao m\u1ed9t l\u01b0\u1ee3ng \u0111ioxit cacbon r\u1ea5t l\u1edbn, t\u0103ng 20% so v\u1edbi l\u01b0\u1ee3ng \u0111\u00e3 c\u00f3 c\u00e1ch \u0111\u00e2y 40 50 n\u0103m tr\u01b0\u1edbc.","\u0110ioxit cacbon c\u00f9ng v\u1edbi h\u01a1i n\u01b0\u1edbc h\u00ecnh th\u00e0nh n\u00ean m\u1ed9t l\u1edbp m\u1ecfng bao ph\u1ee7 Tr\u00e1i \u0111\u1ea5t, n\u00f3 cho nhi\u1ec7t l\u01b0\u1ee3ng t\u1eeb M\u1eb7t tr\u1eddi ph\u00e1t ta \u0111i t\u1edbi m\u1eb7t \u0111\u1ea5t m\u1ed9t c\u00e1ch d\u1ec5 d\u00e0ng, nh\u01b0ng l\u1ea1i h\u1ea5p th\u1ee5 nhi\u1ec7t l\u01b0\u1ee3ng t\u1eeb m\u1eb7t \u0111\u1ea5t t\u00e1n x\u1ea1 v\u00e0o kh\u00f4ng gian r\u1ed3i l\u1ea1i ph\u00e1t \u0111i \u0111\u1ea1i b\u1ed9 ph\u1eadn nhi\u1ec7t l\u01b0\u1ee3ng \u0111\u00f3 xu\u1ed1ng l\u1ea1i m\u1eb7t \u0111\u1ea5t. \u0110i\u1ec1u \u0111\u00f3 c\u00f3 hi\u1ec7u qu\u1ea3 gi\u1ed1ng nh\u01b0 c\u00e1i nh\u00e0 b\u1eb1ng k\u00ednh ho\u1eb7c t\u1ea5m ch\u1ea5t d\u1ebbo m\u1ecfng. N\u00ean hi\u1ec7n t\u01b0\u1ee3ng n\u00e0y \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 hi\u1ec7u \u1ee9ng nh\u00e0 k\u00ednh. N\u1ebfu n\u1ed3ng \u0111\u1ed9 \u0111ioxit cacbon t\u0103ng g\u1ea5p \u0111\u00f4i, nhi\u1ec7t \u0111\u1ed9 kh\u00f4ng kh\u00ed trung b\u00ecnh t\u1ea1i m\u1eb7t \u0111\u1ea5t li\u1ec1n t\u1ea9ng 2 3 \u0111\u1ed9 C. Trong giai \u0111o\u1ea1n 1940 \u0111\u1ebfn 1965, nhi\u1ec7t \u0111\u1ed9 kh\u00f4ng kh\u00ed trung b\u00ecnh \u1edf v\u00e0o tr\u1ea1ng th\u00e1i gi\u1ea3m sau 1980 c\u00f3 xu th\u1ebf t\u0103ng l\u00ean. Tr\u00e1i \u0111\u1ea5t n\u1eb7ng bao nhi\u00eau? Tr\u1ecdng l\u01b0\u1ee3ng c\u1ee7a c\u00f9ng m\u1ed9t v\u1eadt th\u1ec3, \u0111\u1eb7t \u1edf M\u1eb7t tr\u0103ng s\u1ebd nh\u1eb9 h\u01a1n so v\u1edbi Tr\u00e1i \u0111\u1ea5t t\u1edbi 6 l\u1ea9n. C\u00e1c v\u1eadt c\u00f3 tr\u1ecdng l\u01b0\u1ee3ng l\u00e0 do l\u1ef1c h\u00fat Tr\u00e1i \u0111\u1ea5t m\u00e0 sinh ra. Tr\u00e1i \u0111\u1ea5t c\u00f3 kh\u1ed1i l\u01b0\u1ee3ng b\u1eb1ng 5,98 x 1027 gam, x\u1ea5p x\u1ec9 6 tri\u1ec7u tri\u1ec7u tri\u1ec7u kil\u00f4gam. Tr\u1ecdng l\u01b0\u1ee3ng c\u1ee7a m\u1ed9t v\u1eadt th\u1ec3 n\u1eb7ng t\u1ef7 l\u1ec7 thu\u1eadn kh\u1ed1i l\u01b0\u1ee3ng Tr\u00e1i \u0111\u1ea5t v\u00e0 t\u1ef7 l\u1ec7 ngh\u1ecbch v\u1edbi b\u00e1n k\u00ednh Tr\u00e1i \u0111\u1ea5t (6.370 km). N\u1ebfu x\u00e1c \u0111\u1ecbnh \u0111\u01b0\u1ee3c h\u1eb1ng s\u1ed1 t\u1ef7 l\u1ec7 (h\u1eb1ng s\u1ed1 v\u1ea1n v\u1eadt h\u1ea5p d\u1eabn) trong m\u1ed1i quan h\u1ec7 \u0111\u00f3 th\u00ec c\u00f3 th\u1ec3 t\u00ednh ra tr\u1ecdng l\u01b0\u1ee3ng c\u1ee7a Tr\u00e1i \u0111\u1ea5t. Gi\u1eefa th\u1ebf k\u1ef7 XVIII, nh\u00e0 khoa h\u1ecdc Anh Cavendis th\u00f4ng qua th\u1eed nghi\u1ec7m \u0111\u00e3 r\u00fat ra \u0111\u01b0\u1ee3c tr\u1ecb s\u1ed1 ch\u00ednh x\u00e1c c\u1ee7a h\u1eb1ng s\u1ed1 \u0111\u00f3. Cho n\u00ean kh\u1ed1i l\u01b0\u1ee3ng c\u1ee7a Tr\u00e1i \u0111\u1ea5t c\u0169ng t\u00ednh ra \u0111\u01b0\u1ee3c. Bi\u1ebft b\u00e1n k\u00ednh Tr\u00e1i \u0111\u1ea5t c\u00f3 th\u1ec3 t\u00ednh \u0111\u01b0\u1ee3c th\u1ec3 t\u00edch c\u1ee7a Tr\u00e1i \u0111\u1ea5t b\u1eb1ng 1,08 x 1027 cm2 kh\u1ed1i l\u01b0\u1ee3ng ri\u00eang trung b\u00ecnh c\u1ee7a Tr\u00e1i \u0111\u1ea5t b\u1eb1ng kh\u1ed1i l\u01b0\u1ee3ng chia cho th\u1ec3 t\u00edch b\u1eb1ng 5,52 g\/cm3, kh\u1ed1i nham th\u1ea1ch tr\u00ean b\u1ec1 m\u1eb7t Tr\u00e1i \u0111\u1ea5t l\u1edbn g\u1ea5p \u0111\u00f4i. Cho n\u00ean qua \u0111\u00f3 c\u00f3 th\u1ec3 \u0111o\u00e1n h\u1ebft, trong l\u00f2ng \u0111\u1ea5t c\u00f3 th\u1ec3 c\u00f3 c\u00e1c ch\u1ea5t thu\u1ed9c kim lo\u1ea1i n\u1eb7ng nh\u01b0 s\u1eaft, niken... Tr\u00e1i \u0111\u1ea5t quay xung quanh M\u1eb7t tr\u1eddi nh\u01b0 th\u1ebf n\u00e0o? N\u0103m 1543 c\u00f4ng nguy\u00ean, nh\u00e0 thi\u00ean v\u0103n h\u1ecdc ng\u01b0\u1eddi Ba Lan Nicola Kopernik trong t\u00e1c ph\u1ea9m v\u0129 \u0111\u1ea1i c\u1ee7a m\u00ecnh: \u201cThuy\u1ebft thi\u00ean th\u1ec3 v\u1eadn h\u00e0nh\u201d \u0111\u00e3 ch\u1ee9ng minh r\u1eb1ng kh\u00f4ng ph\u1ea3i M\u1eb7t tr\u1eddi chuy\u1ec3n \u0111\u1ed9ng quanh Tr\u00e1i \u0111\u1ea5t m\u00e0 l\u00e0 Tr\u00e1i \u0111\u1ea5t chuy\u1ec3n \u0111\u1ed9ng xung quanh M\u1eb7t tr\u1eddi. \u0110\u00e2y l\u00e0 s\u1ef1 xoay quanh c\u1ee7a Tr\u00e1i \u0111\u1ea5t, th\u1eddi gian Tr\u00e1i \u0111\u1ea5t quay xung quanh M\u1eb7t tr\u1eddi m\u1ed9t v\u00f2ng ch\u00ednh l\u00e0 m\u1ed9t n\u0103m. T\u00ednh theo c\u00f4ng th\u1ee9c \u0111\u1ecbnh lu\u1eadt v\u1ea1n v\u1eadt h\u1ea5p d\u1eabn c\u1ee7a Issac Niut\u01a1n, l\u1ef1c h\u1ea5p d\u1eabn gi\u1eefa Tr\u00e1i \u0111\u1ea5t v\u00e0 M\u1eb7t tr\u1eddi kho\u1ea3ng 3,5 t\u1ef7 Niut\u01a1n. T\u1ed1c \u0111\u1ed9 chuy\u1ec3n \u0111\u1ed9ng theo chu vi h\u00ecnh tr\u00f2n c\u1ee7a Tr\u00e1i \u0111\u1ea5t quanh M\u1eb7t tr\u1eddi \u0111\u1ea1t 30 km\/s. Do c\u00f3 l\u1ef1c li t\u00e2m qu\u00e1n t\u00ednh s\u1ea3n sinh ra v\u00e0 l\u1ef1c h\u1ea5p d\u1eabn c\u1ee7a M\u1eb7t tr\u1eddi v\u1edbi Tr\u00e1i \u0111\u1ea5t l\u00e0 ngang nhau, l\u00e0m cho Tr\u00e1i \u0111\u1ea5t kh\u00f4ng b\u1ecb l\u1ec7ch m\u00e0 tr\u00e1i l\u1ea1i, lu\u00f4n quay xung quanh M\u1eb7t tr\u1eddi. S\u1ef1 th\u1ef1c l\u00e0, qu\u1ef9 \u0111\u1ea1o c\u1ee7a Tr\u00e1i \u0111\u1ea5t kh\u00f4ng ph\u1ea3i l\u00e0 h\u00ecnh tr\u00f2n m\u00e0 l\u00e0 h\u00ecnh b\u1ea9u d\u1ee5c. \u0110\u1ea9u th\u00e1ng m\u1ed9t h\u00e0ng n\u0103m, Tr\u00e1i \u0111\u1ea5t \u0111i qua m\u1ed9t \u0111i\u1ec3m g\u1ea9n nh\u1ea5t v\u1edbi M\u1eb7t tr\u1eddi \u1edf tr\u00ean qu\u1ef9 \u0111\u1ea1o, tr\u00ean ph\u01b0\u01a1ng di\u1ec7n thi\u00ean v\u0103n h\u1ecdc g\u1ecdi \u0111\u00f3 l\u00e0 \u0111i\u1ec3m c\u1eadn nh\u1eadt, l\u00fac n\u00e0y, Tr\u00e1i \u0111\u1ea5t c\u00e1ch M\u1eb7t tr\u1eddi","147,100 tri\u1ec7u km. C\u00f2n v\u00e0o \u0111\u1ea9u th\u00e1ng 7, Tr\u00e1i \u0111\u1ea5t \u0111i qua m\u1ed9t \u0111i\u1ec3m xa v\u1edbi M\u1eb7t tr\u1eddi nh\u1ea5t, \u0111\u00f3 \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 \u0111i\u1ec3m vi\u1ec5n nh\u1eadt; l\u00fac n\u00e0y, Tr\u00e1i \u0111\u1ea5t c\u00e1ch M\u1eb7t tr\u1eddi 152,1tri\u1ec7u km. C\u0103n c\u1ee9 v\u00e0o s\u1ed1 li\u1ec7u n\u00e0y, M\u1eb7t tr\u1eddi m\u00e0 ch\u00fang ta nh\u00ecn th\u1ea5y v\u00e0o th\u00e1ng 1 to h\u01a1n m\u1ed9t ch\u00fat so v\u1edbi M\u1eb7t tr\u1eddi m\u00e0 ch\u00fang ta nh\u00ecn th\u1ea5y v\u00e0o th\u00e1ng 7 h\u00e0ng n\u0103m. Nh\u01b0ng qu\u1ef9 \u0111\u1ea1o c\u1ee7a t l\u00e0 m\u1ed9t h\u00ecnh b\u1ea9u d\u1ee5c g\u1ea9n b\u1eb1ng h\u00ecnh tr\u00f2n, v\u00ec th\u1ebf s\u1ef1 kh\u00e1c bi\u1ec7t n\u00e0y tr\u00ean th\u1ef1c t\u1ebf kh\u00f4ng r\u00f5 r\u00e0ng, m\u1eaft th\u01b0\u1eddng kh\u00f4ng th\u1ec3 n\u00e0o nh\u00ecn th\u1ea5y \u0111\u01b0\u1ee3c, ch\u1ec9 c\u00f3 th\u00f4ng qua vi\u1ec7c \u0111o \u0111\u1ea1c t\u1ef7 m\u1ec9 m\u1edbi c\u00f3 th\u1ec3 ph\u00e1t hi\u1ec7n ra \u0111\u01b0\u1ee3c. Quan tr\u1eafc ch\u00ednh x\u00e1c h\u01a1n n\u1eefa s\u1ebd cho ch\u00fang ta bi\u1ebft r\u1eb1ng qu\u1ef9 \u0111\u1ea1o c\u1ee7a Tr\u00e1i \u0111\u1ea5t v\u00e0 h\u00ecnh b\u1ea9u d\u1ee5c v\u1eabn c\u00f3 s\u1ef1 kh\u00e1c bi\u1ec7t nho nh\u1ecf, \u0111\u00f3 l\u00e0 v\u00ec M\u1eb7t tr\u0103ng v\u00e0 sao Ho\u1ea3, sao Kim v\u00e0 c\u00e1c h\u00e0nh tinh kh\u00e1c \u0111\u1ec1u d\u00f9ng l\u1ef1c h\u1ea5p d\u1eabn c\u1ee7a ch\u00fang t\u00e1c \u0111\u1ed9ng \u0111\u1ebfn s\u1ef1 chuy\u1ec3n \u0111\u1ed9ng c\u1ee7a Tr\u00e1i \u0111\u1ea5t. Nh\u01b0ng ch\u00fang r\u1ea5t nh\u1ecf so v\u1edbi M\u1eb7t tr\u1eddi, t\u00e1c d\u1ee5ng c\u1ee7a l\u1ef1c h\u1ea5p d\u1eabn \u0111\u1ed1i v\u1edbi Tr\u00e1i \u0111\u1ea5t l\u00e0 r\u1ea5t nh\u1ecf, kh\u00f3 m\u00e0 so \u0111\u01b0\u1ee3c v\u1edbi M\u1eb7t tr\u1eddi, cho n\u00ean qu\u1ef9 \u0111\u1ea1o c\u1ee7a Tr\u00e1i \u0111\u1ea5t v\u1eabn r\u1ea5t gi\u1ed1ng v\u1edbi h\u00ecnh b\u1ea9u d\u1ee5c. N\u00f3i m\u1ed9t c\u00e1ch nghi\u00eam t\u00fac, qu\u1ef9 \u0111\u1ea1o quay c\u1ee7a Tr\u00e1i \u0111\u1ea5t l\u00e0 m\u1ed9t \u0111\u01b0\u1eddng cong ph\u1ee9c t\u1ea1p, \u0111\u01b0\u1eddng cong n\u00e0y g\u1ea9n nh\u01b0 m\u1ed9t h\u00ecnh b\u1ea9u d\u1ee5c v\u1edbi \u0111\u1ed9 ch\u00eanh l\u1ec7ch r\u1ea5t nh\u1ecf. C\u00e1c nh\u00e0 thi\u00ean v\u0103n h\u1ecdc \u0111\u00e3 ho\u00e0n to\u00e0n n\u1eafm b\u1eaft \u0111\u01b0\u1ee3c quy lu\u1eadt chuy\u1ec3n \u0111\u1ed9ng ph\u1ee9c t\u1ea1p n\u00e0y c\u1ee7a Tr\u00e1i \u0111\u1ea5t. Tr\u00e1i \u0111\u1ea5t c\u00f3 t\u1eeb bao gi\u1edd? H\u1ec7 M\u1eb7t tr\u1eddi \u0111\u01b0\u1ee3c h\u00ecnh th\u00e0nh t\u1eeb \u0111\u00e1m \u201ctinh v\u00e2n nguy\u00ean thu\u1ef7\u201d c\u00f3 d\u1ea1ng h\u00ecnh \u0111\u0129a tr\u00f2n xoay v\u00f2ng v\u1edbi nhi\u1ec7t \u0111\u1ed9 cao t\u1edbi 2.000 \u0111\u1ed9 C tr\u00ean v\u1ecb tr\u00ed c\u1ee7a Tr\u00e1i \u0111\u1ea5t. Tinh v\u00e2n n\u00e0y do c\u00e1c nguy\u00ean t\u1eed, ph\u00e2n t\u1eed, h\u1ea1t ch\u1ea5t r\u1eafn (b\u1ee5i v\u0169 tr\u1ee5), ch\u1ea5t kh\u00ed d\u1ea1ng ionh\u1ee3p th\u00e0nh. Theo \u0111\u00e0 ngu\u1ed9i l\u1ea1nh \u0111i c\u1ee7a tinh v\u00e2n, b\u1ee5i v\u0169 tr\u1ee5 \u1edf xung quanh. M\u1eb7t tr\u1eddi nguy\u00ean thu\u1ef7 ng\u01b0ng t\u1ee5 th\u00e0nh c\u00e1c kh\u1ed1i ch\u1ea5t r\u1eafn, l\u1eafng \u0111\u1ecdng tr\u00ean m\u1eb7t ph\u1eb3ng c\u1ee7a \u0111\u0129a (x\u00edch \u0111\u1ea1o). B\u1ee5i v\u0169 tr\u1ee5 ch\u1ee7 y\u1ebfu do v\u00e2n th\u1ea1ch silicat c\u00e1c h\u1ee3p ch\u1ea5t c\u00f3 ch\u1ee9a s\u1eaft v.v... t\u1ea1o th\u00e0nh. Th\u00e0nh ph\u1ea9n c\u1ee7a v\u00e2n th\u1ea1ch v\u00e0 c\u1ee7a M\u1eb7t tr\u1eddi gi\u1ed1ng nhau. \u0110i\u1ec1u \u0111\u00f3 ch\u1ee9ng t\u1ecf b\u1ee5i v\u0169 tr\u1ee5 v\u00e0 M\u1eb7t tr\u1eddi v\u1ed1n l\u00e0 t\u1eeb c\u00f9ng \u201ctinh v\u00e2n\u201d h\u00ecnh th\u00e0nh m\u00e0 ra. Sau khi c\u00e1c h\u1ea1t ch\u1ea5t r\u1eafn l\u1eafng \u0111\u1ecdng v\u00e0o trong kho\u1ea3ng th\u1eddi gian 10 tri\u1ec7u 100 tri\u1ec7u n\u0103m, do s\u1ef1 c\u00e2n b\u1eb1ng gi\u1eefa s\u1ee9c h\u00fat c\u1ee7a M\u1eb7t tr\u1eddi v\u00e0 l\u1ef1c ly t\u00e2m m\u00e0 h\u00ecnh th\u00e0nh c\u00e1c h\u00e0nh tinh lo\u1ea1i Tr\u00e1i \u0111\u1ea5t ch\u1ee7 y\u1ebfy do v\u00e2n th\u1ea1ch t\u1ee5 t\u1eadp l\u1ea1i \u1edf v\u00f9ng g\u1ea9n M\u1eb7t tr\u1eddi. \u1ede v\u00f9ng xa M\u1eb7t tr\u1eddi th\u00ec h\u00ecnh th\u00e0nh c\u00e1c h\u00e0nh tinh ki\u1ec3u sao M\u1ed9c do khi v\u0169 tr\u1ee5 v\u00e0 c\u00e1c h\u1ea1t b\u0103ng t\u1ee5 t\u1eadp l\u1ea1i. V\u1ec1 tu\u1ed5i t\u00e1c c\u1ee7a v\u00e2n th\u1ea1ch v\u00e0 c\u1ee7a M\u1eb7t tr\u0103ng, d\u1ef1a v\u00e0o k\u1ebft qu\u1ea3 c\u00e1c nguy\u00ean t\u1ed1 c\u00f3 t\u00ednh ph\u00f3ng x\u1ea1 m\u00e0 ch\u00fang ch\u1ee9a nh\u01b0 urani, thori. cho l\u00e0 4,6 ty tu\u1ed5i. \u0110\u00f3 c\u0169ng l\u00e0 tu\u1ed5i t\u00e1c c\u1ee7a h\u1ec7 Tr\u00e1i \u0111\u1ea5t v\u00e0 h\u1ec7 M\u1eb7t tr\u1eddi. V\u00ec sao \u0111\u00e0n \u00f4ng l\u1ea5y v\u1ee3? T\u1ea1i sao v\u00e0 \u0111i\u1ec1u g\u00ec khi\u1ebfn cho m\u1ed9t anh ch\u00e0ng t\u1ef1 do l\u00f4ng b\u00f4ng v\u00e0 vui th\u00fa, b\u1ed7ng nhi\u00ean","chui t\u1ecdt \u201cv\u00e0o l\u1ed3ng\u201d? T\u1ea1i sao, t\u1ea1i sao th\u1ebf? Theo s\u1ef1 l\u00fd gi\u1ea3i c\u1ee7a c\u00e1c nh\u00e0 t\u00e2m l\u00fd hi\u1ec7n \u0111\u1ea1i, t\u1ea1p ch\u00ed \u201cWoman\u201d \u0111\u00e3 t\u00f3m t\u1eaft th\u00e0nh ba \u0111i\u1ec3m sau: 1.V\u00ec \u0111\u1ed3ng h\u1ed3 sinh h\u1ecdc c\u1ee7a anh ta \u0111\u00e3 g\u00f5 Theo c\u00e1c nh\u00e0 t\u00e2m l\u00fd h\u1ecdc th\u00ec trong m\u1ed7i ng\u01b0\u1eddi ch\u00fang ta c\u00f3 m\u1ed9t nh\u1ecbp s\u1ed1ng \u0111i theo v\u1edbi tr\u1eadt t\u1ef1 thi\u00ean nhi\u00ean g\u1ecdi l\u00e0 \u0111\u1ed3ng h\u1ed3 sinh h\u1ecdc. N\u1ebfu \u0111\u1ec3 t\u1ef1 do, kh\u00f4ng g\u00f2 \u00e9p g\u00ec c\u1ea3 th\u00ec t\u1ef1 nhi\u00ean \u0111\u1ebfn m\u1ed9t l\u00fac n\u00e0o \u0111\u00f3 c\u00e1i \u0111\u1ed3ng h\u1ed3 sinh h\u1ecdc \u1ea5y g\u00f5 nh\u1ecbp li\u00ean t\u1ee5c b\u00e1o cho anh ch\u00e0ng \u0111\u1ed9c th\u00e2n kia r\u1eb1ng \u0111\u00e3 \u0111\u1ebfn l\u00fac anh ta ph\u1ea3i c\u00f3 v\u1ee3, m\u1ed9t ng\u01b0\u1eddi \u0111\u00e0n b\u00e0, k\u1ebft h\u1ee3p v\u1edbi anh ta \u0111\u1ec3 gi\u1eef th\u0103ng b\u1eb1ng t\u00e2m sinh l\u00fd cho anh, n\u1ebfu kh\u00f4ng th\u1ea9n kinh anh r\u1ea5t d\u1ec5 b\u1ecb \u201cch\u1eadp m\u1ea1ch\u201d. Ti\u1ebfng g\u00f5 b\u00e1o hi\u1ec7u n\u00e0y r\u1ea5t m\u1ea1nh, n\u00f3 th\u00f4i th\u00fac tri\u1ec1n mi\u00ean khi\u1ebfn cho anh thanh ni\u00ean kia \u0103n kh\u00f4ng ngon, ng\u1ee7 kh\u00f4ng y\u00ean, t\u00e2m tr\u00ed tr\u1edf n\u00ean ng\u01a1 ng\u1ea9n, cho \u0111\u1ebfn khi anh ta g\u1eb7p \u0111\u01b0\u1ee3c m\u1ed9t ng\u01b0\u1eddi ph\u1ee5 n\u1eef, v\u00e0 k\u1ebft h\u01a1p v\u1edbi ng\u01b0\u1eddi \u1ea5y t\u1ea1o n\u00ean m\u1ed9t l\u1ee9a \u0111\u00f4i thu\u1eadn h\u1ee3p thi\u00ean nhi\u00ean. V\u1eady l\u00e0 anh ta c\u00f3 m\u1ed9t gia \u0111\u00ecnh h\u1ea1nh ph\u00fac. B\u1edfi th\u1ebf, tr\u1eed nh\u1eefng ng\u01b0\u1eddi qu\u00e1 \u0111\u1eb7c bi\u1ec7t, qu\u00e1 khi\u1ebfm khuy\u1ebft, c\u00f2n ng\u01b0\u1eddi \u0111\u00e0n \u00f4ng n\u00e0o th\u00ec c\u0169ng s\u1ebd c\u00f3 v\u1ee3, ng\u01b0\u1eddi \u0111\u00e0n b\u00e0 n\u00e0o r\u1ed3i c\u0169ng s\u1ebd c\u00f3 ch\u1ed3ng. L\u00fac \u1ea5y chi\u1ebfc \u0111\u1ed3ng h\u1ed3 sinh h\u1ecdc n\u01a1i m\u1ed7i ng\u01b0\u1eddi m\u1edbi lu\u00f4n th\u00f4i th\u00fac ng\u01b0\u1eddi \u1ea5y ph\u1ea3i l\u1eadp gia \u0111\u00ecnh khi \u0111\u1ebfn gi\u1edd \u0111\u00e3 \u0111\u1ecbnh... Chi\u1ebfc \u0111\u1ed3ng h\u1ed3 n\u00e0y \u1edf m\u1ed7i ng\u01b0\u1eddi m\u1ed7i kh\u00e1c n\u00ean c\u00f3 k\u1ebb s\u1edbm l\u1eadp gia \u0111\u00ecnh, c\u00f3 ng\u01b0\u1eddi th\u00ec mu\u1ed9n m\u00e0ng ch\u1eadm tr\u1ec5. Nh\u01b0ng tr\u01b0\u1edbc sau r\u1ed3i c\u0169ng c\u00f3 gia \u0111\u00ecnh. 2.V\u00ec anh ta c\u1ea3m th\u1ea5y b\u00ecnh y\u00ean v\u1edbi ng\u01b0\u1eddi ph\u1ee5 n\u1eef \u1ea5y? \u0110\u1ebfn khi b\u1ea1n s\u1ebd h\u1ecfi: t\u1ea1i sao anh thanh ni\u00ean \u1ea5y ch\u1ecdn c\u00f4 n\u00e0y m\u00e0 kh\u00f4ng ch\u1ecdn c\u00f4 kia? \u0110i\u1ec1u g\u00ec chi ph\u1ed1i anh ta? Tr\u01b0\u1edbc nay m\u1ecdi ng\u01b0\u1eddi quen b\u1ea3o: V\u00ec duy\u00ean ph\u1eadn. Th\u1ef1c ra, m\u1ed7i chi\u1ebfc \u0111\u1ed3ng h\u1ed3 sinh h\u1ecdc \u1edf m\u1ed7i ng\u01b0\u1eddi \u0111\u1ec1u c\u00f3 t\u1ea9n s\u1ed1 dao \u0111\u1ed9ng nh\u1ea5t \u0111\u1ecbnh. Khi g\u1eb7p m\u1ed9t t\u1ea9n s\u1ed1 giao thoa th\u00edch h\u1ee3p ho\u00e0 nh\u1ecbp v\u1edbi n\u00f3, chi\u1ebfc \u0111\u1ed3ng h\u1ed3 \u1ea5y s\u1ebd l\u00ean ti\u1ebfng ho\u00e0 \u00e2m, t\u1ea1o cho hai ng\u01b0\u1eddi v\u00e0 nh\u1ea5t l\u00e0 anh ch\u00e0ng thanh ni\u00ean kia c\u00f3 m\u1ed9t c\u1ea3m gi\u00e1c b\u00ecnh an h\u1ea1nh ph\u00fac. Th\u1ebf l\u00e0 anh ta ch\u1ecdn ng\u01b0\u1eddi ph\u1ee5 n\u1eef mang chi\u1ebfc \u0111\u1ed3ng h\u1ed3 sinh h\u1ecdc kia c\u0169ng g\u00f5 nh\u1ecbp tr\u1ecdn \u0111\u1eddi v\u1edbi anh! Khi ta \u0111\u1ed1i di\u1ec7n v\u1edbi m\u1ed9t ng\u01b0\u1eddi m\u00e0 ta c\u00f3 c\u1ea3m gi\u00e1c an l\u00f2ng, tin t\u01b0\u1edfng th\u00ec c\u00f2n g\u00ec ng\u0103n c\u1ea3n ta ng\u00e3 v\u00e0o v\u00f2ng tay ng\u01b0\u1eddi \u1ea5y \u0111ang dang r\u1ed9ng v\u00e0 \u0111\u00f3n ch\u1edd ta! B\u1edfi th\u1ebf, khi m\u1ed9t anh","thanh ni\u00ean b\u1eaft g\u1eb7p hai, ba hay nhi\u1ec1u chi\u1ebfc \u0111\u1ed3ng h\u1ed3 sinh h\u1ecdc h\u1ee3p v\u1edbi anh ta, nh\u01b0ng anh ta ng\u00e3 ngay v\u00e0o ng\u01b0\u1eddi n\u00e0o may m\u1eafn dang tay \u0111\u00f3n anh ta tr\u01b0\u1edbc v\u00e0 anh ta c\u1ea3m th\u1ea5y b\u00ecnh an. 3. V\u00ec anh ta t\u00ecm th\u1ea5y \u1edf ng\u01b0\u1eddi ph\u1ee5 n\u1eef \u0111i\u1ec1u m\u00e0 anh ta thi\u1ebfu? Kh\u00f4ng ph\u1ea3i v\u1ea5n \u0111\u1ec1 ti\u1ec1n b\u1ea1c, c\u1ee7a c\u1ea3i m\u00e0 v\u1ec1 t\u00e2m l\u00fd, t\u00ednh t\u00ecnh hay c\u1ea3 tr\u00ed tu\u1ec7 n\u1eefa. C\u00f3 anh y\u00eau m\u1ed9t ph\u1ee5 n\u1eef v\u00ec th\u1ea5y ng\u01b0\u1eddi \u1ea5y t\u1ebf nh\u1ecb, hi\u1ec3u m\u00ecnh, t\u1ecf ra r\u1ea5t s\u00e0nh t\u00e2m l\u00fd c\u1ee7a m\u00ecnh, c\u00f2n t\u1ef1 th\u1ea5y b\u1ea3n th\u00e2n m\u00ecnh th\u00ec c\u1ee5c m\u1ecbch, vung v\u1ec1. C\u00f3 anh y\u00eau m\u1ed9t ph\u1ee5 n\u1eef v\u00ec th\u1ea5y ng\u01b0\u1eddi ph\u1ee5 n\u1eef \u1ea5y t\u00ednh t\u00ecnh d\u1ecbu d\u00e0ng trong khi m\u00ecnh n\u00f3ng nh\u01b0 l\u1eeda, ho\u1eb7c c\u00f4 \u1ea5y vui v\u1ebb ho\u1ea1t b\u00e1t trong khi m\u00ecnh m\u1edf mi\u1ec7ng kh\u00f4ng ra h\u01a1i. C\u00f3 anh y\u00eau ng\u01b0\u1eddi b\u1ea1n g\u00e1i v\u00ec th\u1ea5y c\u00f4 \u1ea5y r\u1ea5t kh\u00f4n ngoan, t\u00ednh to\u00e1n m\u1ecdi vi\u1ec7c r\u1ea5t kh\u00e9o l\u00e9o trong khi m\u00ecnh th\u00ec ngu ng\u01a1 d\u1ec5 b\u1ecb thi\u00ean h\u1ea1 g\u1ea1t g\u1eabm nhi\u1ec1u chuy\u1ec7n. N\u00f3i chung l\u00e0 khi m\u1ed9t anh ch\u00e0ng thanh ni\u00ean l\u1ea5y v\u1ee3 nh\u01b0 \u0111i t\u00ecm m\u1ed9t s\u1ef1 b\u00f9 tr\u1eeb cho s\u1ef1 thi\u1ebfu h\u1ee5t t\u00e2m l\u00fd, t\u00ecnh c\u1ea3m hay tr\u00ed tu\u1ec7 n\u01a1i anh ta. C\u0169ng c\u00f3 anh \u0111i t\u00ecm s\u1ef1 b\u00f9 tr\u1eeb v\u1ec1 t\u00e0i ch\u00ednh, c\u1ee7a c\u1ea3i. nh\u01b0ng nh\u1eefng anh ch\u1ea3ng n\u00e0y tr\u01b0\u1edbc sau g\u00ec c\u0169ng chu\u1ed1c l\u1ea5y b\u1ea5t h\u1ea1nh! V\u00e0 thanh ni\u00ean ng\u00e0y nay ph\u1ea9n l\u1edbn l\u1ea5y v\u1ee3 mu\u1ed9n v\u00ec m\u1ed9t trong ba l\u00fd do sau: -Chi\u1ebfc \u0111\u1ed3ng h\u1ed3 sinh h\u1ecdc \u1edf h\u1ecd ch\u01b0a l\u00ean ti\u1ebfng g\u00f5 nh\u1ecbp th\u00f4i th\u00fac. -H\u1ecd th\u1ea5y kh\u00f4ng an to\u00e0n tr\u01b0\u1edbc m\u1ed9t s\u1ed1 ng\u01b0\u1eddi ph\u1ee5 n\u1eef m\u00e0 h\u1ecd g\u1eb7p. - H\u1ecd kh\u00f4ng t\u00ecm th\u1ea5y \u1edf ph\u1ee5 n\u1eef c\u00e1i b\u00f9 tr\u1eeb cho nh\u1eefng g\u00ec m\u00e0 h\u1ecd \u0111ang thi\u1ebfu. Th\u1ebf th\u00f4i, th\u1eddi bu\u1ed5i c\u1ee7a t\u1ef1 do v\u1ec1 ch\u00ednh tr\u1ecb, x\u00e3 h\u1ed9i, t\u00edn ng\u01b0\u1ee1ng, \u0111\u1ea1o \u0111\u1ee9c. Ai \u00e9p \u0111\u01b0\u1ee3c m\u1ed9t thanh ni\u00ean l\u1ea5y v\u1ee3? Tr\u1eeb khi, ch\u00ednh anh ta mong mu\u1ed1n m\u00e0 th\u00f4i. Khi ch\u1edbp m\u1eaft, th\u1ebf gi\u1edbi ng\u1eebng tr\u00f4i?","Th\u1ef1c t\u1ebf l\u00e0 khi ch\u1edbp m\u1eaft, con ng\u01b0\u1eddi b\u1ecb t\u00e1ch ra kh\u1ecfi th\u1ebf gi\u1edbi xung quanh trong kho\u1ea3nh kh\u1eafc. Song hi\u1ebfm khi ta nh\u1eadn th\u1ee9c \u0111\u01b0\u1ee3c \u0111i\u1ec1u n\u00e0y b\u1edfi v\u00ec nh\u1eefng ph\u1ea9n n\u00e3o \u0111i\u1ec1u khi\u1ec3n th\u1ecb gi\u00e1c c\u1ee7a ch\u00fang ta khi \u0111\u00f3 t\u1ea1m th\u1eddi b\u1ecb \u201c\u0111\u00f3ng\u201d. \u201cCon ng\u01b0\u1eddi s\u1ebd nh\u1eadn ra ngay l\u1eadp t\u1ee9c khi th\u1ebf gi\u1edbi xung quanh \u0111\u1ed9t nhi\u00ean t\u1ed1i om, \u0111\u1eb7c bi\u1ec7t l\u00e0 khi n\u00f3 ch\u1ec9 x\u1ea3y ra trong v\u00e0i gi\u00e2y. Song \u0111\u1ed1i v\u1edbi c\u00e1i ch\u1edbp m\u1eaft th\u00ec r\u1ea5t hi\u1ebfm khi nh\u1eadn ra, m\u1eb7c d\u00f9 c\u1eed \u0111\u1ed9ng n\u00e0y c\u0169ng l\u00e0m gi\u1ea3m c\u01b0\u1eddng \u0111\u1ed9 \u00e1nh s\u00e1ng t\u01b0\u01a1ng \u0111\u01b0\u01a1ng t\u1edbi m\u1eaft\u201d, ti\u1ebfn s\u0129 Davina Bristow, \u0110\u1ea1i h\u1ecdc College London(Anh) cho bi\u1ebft. C\u00f3 th\u1ec3 v\u00ec vi\u1ec7c ch\u1edbp m\u1eaft l\u00e0m cho \u201cc\u00e1i nh\u00ecn v\u00e0o th\u1ebf gi\u1edbi b\u1ecb gi\u00e1n \u0111o\u1ea1n\u201d. Th\u00f4ng th\u01b0\u1eddng, m\u1ed9t c\u00e1i ch\u1edbp m\u1eaft k\u00e9o d\u00e0i t\u1eeb 100 t\u1edbi 150 milli gi\u00e2y v\u00e0 con ng\u01b0\u1eddi th\u01b0\u1eddng ch\u1edbp t\u1eeb 10 t\u1edbi 15 l\u1ea9n trong m\u1ed9t ph\u00fat \u0111\u1ec3 l\u00e0m \u1ea9m v\u00e0 cung c\u1ea5p oxi cho gi\u00e1c m\u1ea1c. Trong th\u1eddi gian ch\u1edbp m\u1eaft, th\u1ecb gi\u00e1c s\u1ebd kh\u00f4ng ghi h\u00ecnh v\u00e0 s\u1ebd kh\u00f4ng thu nh\u1eadn \u00e1nh s\u00e1ng, khi \u0111\u00f3 m\u1ecdi th\u1ee9 trong gi\u00e2y l\u00e1t \u0111i v\u00e0o b\u00f3ng t\u1ed1i. Bristow v\u00e0 c\u00e1c c\u1ed9ng s\u1ef1 \u0111\u00e3 ph\u00e1t hi\u1ec7n ra v\u00ec sao con ng\u01b0\u1eddi hi\u1ebfm khi nh\u1eadn th\u1ee9c \u0111\u01b0\u1ee3c nh\u1eefng \u201ckho\u1ea3nh kh\u1eafc t\u1eaft \u0111\u00e8n\u201d \u0111\u00f3. Nh\u00f3m \u0111\u00e3 s\u1eed d\u1ee5ng m\u1ed9t thi\u1ebft b\u1ecb chuy\u00ean d\u1ee5ng \u0111\u1ec3 \u0111\u00e1nh gi\u00e1 \u1ea3nh h\u01b0\u1edfng c\u1ee7a c\u1eed \u0111\u1ed9ng ch\u1edbp m\u1eaft l\u00ean b\u1ed9 n\u00e3o. Thi\u1ebft b\u1ecb n\u00e0y g\u1ed3m c\u00e1c \u0111\u00e8n ph\u00e1t quang, \u0111\u01b0\u1ee3c \u0111\u1eb7t v\u00e0o mi\u1ec7ng c\u1ee7a m\u1ed9t s\u1ed1 ng\u01b0\u1eddi t\u00ecnh nguy\u1ec7n. Trong khi \u0111\u00f3, h\u1ecd ph\u1ea3i \u0111eo k\u00ednh b\u1ea3o h\u1ed9 ch\u1ed1ng ch\u00f3i m\u1eaft v\u00e0 n\u1eb1m trong m\u1ed9t m\u00e1y qu\u00e9t c\u1ed9ng h\u01b0\u1edfng t\u1eeb (FMRI). \u00c1nh s\u00e1ng t\u1eeb \u0111\u00e8n quanh chi\u1ec1u l\u00ean v\u00f5ng m\u1ea1c v\u00e0 n\u00f3 kh\u00f4ng thay \u0111\u1ed5i k\u1ec3 c\u1ea3 khi \u0111\u1ed1i t\u01b0\u1ee3ng ch\u1edbp m\u1eaft. Quan s\u00e1t qua m\u00e1y ch\u1ee5p n\u00e3o cho th\u1ea5y, c\u1eed \u0111\u1ed9ng ch\u1edbp m\u1eaft \u0111\u00e3 k\u00ecm n\u00e9n ho\u1ea1t \u0111\u1ed9ng c\u1ee7a v\u1ecf n\u00e3o th\u1ecb gi\u00e1c v\u00e0 nh\u1eefng v\u00f9ng \u1edf \u0111\u1ec9nh \u0111\u1ea9u v\u00e0 tr\u01b0\u1edbc tr\u00e1n. \u0110\u00e2y l\u00e0 nh\u1eefng ph\u1ea9n n\u00e3o th\u01b0\u1eddng \u0111\u01b0\u1ee3c k\u00edch ho\u1ea1t khi con ng\u01b0\u1eddi d\u00f9ng m\u1eaft \u0111\u1ec3 nh\u1eadn bi\u1ebft s\u1ef1 ki\u1ec7n ho\u1eb7c v\u1eadt th\u1ec3 \u1edf th\u1ebf gi\u1edbi b\u00ean ngo\u00e0i. \u201cTrong kho\u1ea3nh kh\u1eafc ch\u1edbp m\u1eaft, nh\u1eefng v\u00f9ng n\u00e3o li\u00ean quan \u0111\u1ebfn th\u1ecb gi\u00e1c b\u1ecb v\u00f4 hi\u1ec7u ho\u00e1, \u0111\u00e2y c\u00f3 th\u1ec3 ch\u00ednh l\u00e0 c\u01a1 ch\u1ebf th\u1ea9n kinh ng\u0103n c\u1ea3n b\u1ed9 n\u00e3o nh\u1eadn th\u1ee9c r\u1eb1ng m\u00ed m\u1eaft \u0111\u00e3 bao tr\u00f9m \u0111\u1ed3ng t\u1eed trong th\u1eddi gian ch\u1edbp m\u1eaft v\u00e0 r\u1eb1ng th\u1ebf gi\u1edbi b\u00ean ngo\u00e0i \u0111\u00e3 t\u1ed1i om\u201d, Bristowk\u1ebft lu\u1eadn. N\u00ean r\u00e8n luy\u1ec7n tay tr\u00e1i ra sao? Th\u1ef1c t\u1ebf, hai b\u00e1n c\u1ea9u n\u00e3o v\u1eeba c\u00f3 s\u1ef1 ph\u00e2n c\u00f4ng, h\u1ee3p t\u00e1c, b\u1ed5 sung, v\u1eeba h\u1ea1n ch\u1ebf v\u00e0 b\u00f9 \u0111\u1eafp cho nhau. Th\u00f4ng th\u01b0\u1eddng, hai b\u00e1n c\u1ea9u n\u00e3o h\u1ee3p t\u00e1c v\u1edbi nhau c\u00f9ng ho\u1ea1t \u0111\u1ed9ng. Nh\u1edd v\u1eady, b\u1ea1n m\u1edbi c\u00f3 c\u00e1c c\u1eed \u0111\u1ed9ng ch\u00ednh x\u00e1c. B\u1ea1n luy\u1ec7n t\u1eadp tay tr\u00e1i, kh\u00f4ng c\u00f3 ngh\u0129a l\u00e0 \u0111\u1ec3 bi\u1ebfn m\u00ecnh th\u00e0nh ng\u01b0\u1eddi thu\u1eadn tay tr\u00e1i, m\u00e0 ch\u1ec9 l\u00e0 \u0111\u1ec3 t\u0103ng c\u01b0\u1eddng ho\u1ea1t \u0111\u1ed9ng ph\u00eda b\u00ean tr\u00e1i, k\u00edch th\u00edch s\u1ef1 ph\u00e1t tri\u1ec3n \u0111\u1ed3ng \u0111\u1ec1u c\u1ee7a n\u00e3o b\u1ed9. B\u01b0\u1edbc th\u1ee9 nh\u1ea5t, b\u1ea1n c\u00f3 th\u1ec3 co du\u1ed7i ng\u00f3n tay tr\u00e1i, l\u1ea9n l\u01b0\u1ee3t t\u1eebng ng\u00f3n m\u1ed9t. L\u00e0m \u0111i l\u00e0m l\u1ea1i cho \u0111\u1ebfn khi th\u00e0nh th\u1ea1o. B\u01b0\u1edbc th\u1ee9 hai, l\u00e0m m\u1ed9t s\u1ed1 vi\u1ec7c kh\u00e9o l\u00e9o b\u1eb1ng tay tr\u00e1i, nh\u01b0 x\u00e2u kim, v\u1ebd tranh. B\u01b0\u1edbc th\u1ee9 ba, h\u00e3y l\u00e0m b\u1eb1ng tay tr\u00e1i nh\u1eefng vi\u1ec7c tr\u01b0\u1edbc kia ch\u1ec9 c\u00f3","tay ph\u1ea3i m\u1edbi l\u00e0m \u0111\u01b0\u1ee3c cho \u0111\u1ebfn khi th\u00e0nh th\u1ea1o. H\u00e3y ki\u00ean tr\u00ec, b\u1ea1n s\u1ebd d\u1ea9n th\u1ea5y r\u1eb1ng kh\u00f4ng nh\u1eefng b\u1ea1n c\u00f3 \u0111\u00f4i tay kh\u00e9o l\u00e9o, m\u00e0 c\u01a1 th\u1ec3 c\u0169ng s\u1ebd nhanh nh\u1eb9n h\u01a1n, ngh\u0129 \u0111\u01b0\u1ee3c nhanh h\u01a1n. Tr\u00ed th\u00f4ng minh ph\u00e1t tri\u1ec3n r\u00f5 r\u1ec7t! Sau c\u00f9ng, thu\u1eadn tay ph\u1ea3i hay thu\u1eadn tay tr\u00e1i \u0111\u1ec1u do b\u1ea9m sinh. C\u00f3 ng\u01b0\u1eddi coi thu\u1eadn tay tr\u00e1i l\u00e0 m\u1ed9t t\u1eadt x\u1ea5u, ra s\u1ee9c s\u1eeda ch\u1eefa. \u0110i\u1ec1u n\u00e0y l\u00e0 r\u1ea5t sai l\u1ea9m. C\u00e1c nh\u00e0 khoa h\u1ecdc \u0111\u00e3 l\u00e0m cu\u1ed9c ph\u1ecfng v\u1ea5n \u1edf hai nh\u00f3m tr\u1ebb em: Nh\u00f3m th\u1ee9 nh\u1ea5t g\u1ed3m c\u00e1c em thu\u1eadn tay tr\u00e1i \u0111\u01b0\u1ee3c \u201cs\u1eeda ch\u1eefa\u201d th\u00e0nh thu\u1eadn tay ph\u1ea3i, v\u00e0 nh\u00f3m th\u1ee9 hai g\u1ed3m c\u00e1c em thu\u1eadn tay tr\u00e1i t\u1ef1 nhi\u00ean. K\u1ebft qu\u1ea3, nhi\u1ec1u em \u1edf nh\u00f3m th\u1ee9 nh\u1ea5t n\u00f3i n\u0103ng kh\u00f4ng l\u01b0u lo\u00e1t, tr\u00ed l\u1ef1c ph\u00e1t tri\u1ec3n ch\u1eadm. Nh\u00f3m th\u1ee9 hai th\u00ec ng\u01b0\u1ee3c l\u1ea1i: C\u00e1c emtr\u1ea3 l\u1eddi l\u01b0u lo\u00e1t nh\u01b0 m\u1ecdi \u0111\u1ee9a tr\u1ebb b\u00ecnh th\u01b0\u1eddng kh\u00e1c. Nh\u01b0 v\u1eady, vi\u1ec7c c\u1ed1 c\u00f4ng s\u1eeda ch\u1eefa cho ng\u01b0\u1eddi thu\u1eadn tay tr\u00e1i ch\u1ec9 c\u00f3 h\u1ea1i m\u00e0 th\u00f4i. T\u1eadp luy\u1ec7n tay tr\u00e1i s\u1ebd th\u00f4ng minh h\u01a1n? Ng\u01b0\u1eddi thu\u1eadn tay tr\u00e1i nhanh nh\u1eb9n h\u01a1n h\u1eb3n ng\u01b0\u1eddi thu\u1eadn tay ph\u1ea3i. Theo th\u1ed1ng k\u00ea, 15 em trong \u0111\u1ed9i \u0111\u1ea5u ki\u1ebfm Ph\u00e1p th\u00ec c\u00f3 8 em thu\u1eadn tay tr\u00e1i. M\u1ed9t th\u1eddi gian, gi\u00e0 n\u1eeda c\u00e1c th\u00e0nh vi\u00ean trong \u0111\u1ed9i tuy\u1ec3n b\u00f3ng b\u00e0n Trung Qu\u1ed1c kh\u00f4ng thu\u1eadn tay ph\u1ea3i. Kh\u00f4ng nh\u1eefng ho\u1ea1t b\u00e1t h\u01a1n, n\u1ebfu ch\u1ecbu kh\u00f3 luy\u1ec7n t\u1eadp tay tr\u00e1i, b\u1ea1n s\u1ebd th\u00f4ng minh h\u01a1n \u0111\u1ea5y! N\u00e3o b\u1ed9 chia th\u00e0nh 2 b\u00e1n c\u1ea9u: b\u00e1n c\u1ea9u n\u00e3o tr\u00e1i v\u00e0 b\u00e1n c\u1ea9u n\u00e3o ph\u1ea3i. M\u1ed7i b\u00ean n\u00e3o b\u1ed9 c\u00f3 ch\u1ee9c n\u0103ng thi\u00ean v\u1ec1 c\u00e1c ho\u1ea1t \u0111\u1ed9ng \u1edf ph\u00eda b\u00ean kia c\u1ee7a c\u01a1 th\u1ec3. B\u00e1n c\u1ea9u n\u00e3o tr\u00e1i chi ph\u1ed1i ph\u1ea9n l\u1edbn ho\u1ea1t \u0111\u1ed9ng c\u1ee7a n\u1eeda ph\u1ea3i c\u01a1 th\u1ec3, c\u00f3 quan h\u1ec7 \u0111\u1eb7c bi\u1ec7t v\u1edbi s\u1ef1 ph\u00e1t tri\u1ec3n ng\u00f4n ng\u1eef, g\u1ecdi l\u00e0 \u201cb\u00e1n c\u1ea9u \u01b0u th\u1ebf ng\u00f4n ng\u1eef\u201d. \u1ede \u0111\u00e2y, c\u00e1c xung c\u1ea3m gi\u00e1c t\u1eadp h\u1ee3p \u1edf m\u1ee9c cao nh\u1ea5t \u0111\u1ec3 h\u00ecnh th\u00e0nh t\u00edn hi\u1ec7u ng\u00f4n ng\u1eef v\u00e0 kh\u00e1i ni\u1ec7m tr\u1eebu t\u01b0\u1ee3ng. Do \u0111\u00f3, ch\u1ee9c n\u0103ng c\u1ea3u b\u00e1n c\u1ea9u n\u00e3o tr\u00e1i thi\u00ean v\u1ec1 giai \u0111o\u1ea1n nh\u1eadn th\u1ee9c l\u00fd t\u00ednh, v\u00e0 h\u00ecnh th\u00e0nh t\u01b0 duy tr\u1eebu t\u01b0\u1ee3ng c\u1ee7a con ng\u01b0\u1eddi. B\u00e1n c\u1ea9u n\u00e3o ph\u1ea3i chi ph\u1ed1i n\u1eeda b\u00ean tr\u00e1i c\u01a1 th\u1ec3. Th\u00f4ng qua s\u1ef1 ch\u1ec9nh h\u1ee3p, c\u00e1c xung c\u1ea3m gi\u00e1c t\u1ea1o ra h\u00ecnh \u1ea3nh c\u1ee5 th\u1ec3 v\u1ec1 v\u1ea1n v\u1eadt, con ng\u01b0\u1eddi, kh\u00f4ng gian v\u00e0 th\u1eddi gian. Do \u0111\u00f3, b\u00e1n c\u1ea9u n\u00e3o ph\u1ea3i thi\u00ean v\u1ec1 giai \u0111o\u1ea1n nh\u1eadn th\u1ee9c c\u1ea3m t\u00ednh, g\u1ecdi l\u00e0 \u201cb\u00e1n c\u1ea9u \u01b0u th\u1ebf kh\u00f4ng l\u1eddi\u201d. B\u00e1n c\u1ea9u n\u00e3o tr\u00e1i \u0111i\u1ec1u khi\u1ec3n tay ph\u1ea3i, b\u00e1n c\u1ea9u n\u00e3o ph\u1ea3i \u0111i\u1ec1u khi\u1ec3n tay tr\u00e1i. N\u1ebfu ta v\u1eadn \u0111\u1ed9ng tay (nh\u1ea5t l\u00e0 c\u00e1c ng\u00f3n tay), ta c\u00f3 th\u1ec3 k\u00edch th\u00edch t\u1ebf b\u00e0o n\u00e3o \u1edf khu v\u1ef1c nh\u1ea5t \u0111\u1ecbnh, l\u00e0m cho n\u00e3o ph\u00e1t tri\u1ec3n. \u0110i\u1ec1u \u0111\u00f3 c\u00f3 ngh\u0129a l\u00e0, n\u1ebfu ng\u01b0\u1eddi n\u00e0o th\u01b0\u1eddng d\u00f9ng tay ph\u1ea3i, n\u00e3o tr\u00e1i s\u1ebd ph\u00e1t tri\u1ec3n h\u01a1n v\u00e0 ng\u01b0\u1ee3c l\u1ea1i. Qu\u00e1 tr\u00ecnh t\u1eeb th\u1ecb gi\u00e1c t\u1edbi ph\u1ea3n \u1ee9ng \u1edf ng\u01b0\u1eddi thu\u1eadn tay ph\u1ea3i v\u00e0 tay tr\u00e1i c\u00f3 kh\u00e1c nhau. \u1ede ng\u01b0\u1eddi thu\u1eadn tay ph\u1ea3i, \u0111\u01b0\u1eddng n\u1ed1i th\u1ea9n kinh c\u00f3 d\u1ea1ng: \u201cb\u00e1n c\u1ea9u n\u00e3o ph\u1ea3i b\u00e1n c\u1ea9u n\u00e3o tr\u00e1i -tay ph\u1ea3i\u201d. \u1ede ng\u01b0\u1eddi thu\u1eadn tay tr\u00e1i: \u201cb\u00e1n c\u1ea9u n\u00e3o ph\u1ea3i - taytr\u00e1i\u201d. R\u00f5 r\u00e0ng, th\u00f4ng tin t\u1eeb th\u1ecb gi\u00e1c \u0111\u1ebfn \u0111\u1ed9ng t\u00e1c \u1edf ng\u01b0\u1eddi thu\u1eadn tay tr\u00e1i b\u1edbt \u0111\u01b0\u1ee3c m\u1ed9t kh\u00e2u, do \u0111\u00f3 anh ta ph\u1ea3n \u1ee9ng nhanh h\u01a1n ng\u01b0\u1eddi thu\u1eadn tay ph\u1ea3i.","Ng\u01b0\u1eddi thu\u1eadn tay ph\u1ea3i, m\u1ed7i l\u1ea9n d\u00f9ng tay tr\u00e1i \u0111\u1ec1u c\u1ea3m th\u1ea5y ng\u01b0\u1ee3ng ng\u1ecbu, th\u1eadm ch\u00ed c\u00f2n kh\u00f4ng l\u00e0m n\u1ed5i m\u1ed9t vi\u1ec7c nh\u1ecf nh\u01b0 c\u1ea9m \u0111\u00f4i \u0111\u0169a ch\u1eb3ng h\u1ea1n. T\u1ea1i sao khi c\u00f3 gi\u00f3 l\u1ea1i th\u1ea5y l\u1ea1nh h\u01a1n? Ch\u1eafc h\u1eb3n ai c\u0169ng bi\u1ebft r\u1eb1ng tr\u1eddi r\u00e9t m\u00e0 im gi\u00f3 th\u00ec d\u1ec5 ch\u1ecbu h\u01a1n so v\u1edbi l\u00fac c\u00f3 gi\u00f3. Nhung, kh\u00f4ng ph\u1ea3i t\u1ea5t c\u1ea3 m\u1ecdi ngu\u1eddi \u0111\u1ec1u bi\u1ebft nguy\u00ean nh\u00e2n c\u1ee7a hi\u1ec7n tu\u1ee3ng \u1ea5y. \u201cCh\u1ec9 c\u00e1c sinh v\u1eadt m\u1edbi c\u1ea3m th\u1ea5y gi\u00e1 bu\u1ed1t khi c\u00f3 gi\u00f3\u201d, c\u00f2n c\u00e1c v\u1eadt v\u00f4 sinh th\u00ec kh\u00f4ng. Ch\u1eb3ng h\u1ea1n, nhi\u1ec7t k\u1ebf s\u1ebd kh\u00f4ng h\u1ec1 t\u1ee5t xu\u1ed1ng khi \u0111\u1ec3 n\u00f3 ra ngo\u00e0i tr\u1eddi \u0111ang c\u00f3 l\u1ed1c. Tru\u1edbc h\u1ebft, s\u1edf d\u0129 ta c\u1ea3m th\u1ea5y r\u00e9t bu\u1ed1t trong nh\u1eefng ng\u00e0y \u0110\u00f4ng c\u00f3 gi\u00f3 l\u00e0 v\u00ec nhi\u1ec7t t\u1eeb m\u1eb7t ta (v\u00e0 n\u00f3i chung l\u00e0 t\u1eeb to\u00e0n th\u00e2n ta) to\u1ea3 ra l\u00fac \u1ea5y nhi\u1ec1u h\u01a1n h\u1eb3n l\u00fac tr\u1eddi im gi\u00f3. Khi \u0111\u1ee9ng gi\u00f3, l\u1edbp kh\u00f4ng kh\u00ed b\u1ecb th\u00e2n th\u1ec3 ta l\u00e0m n\u00f3ng l\u00ean kh\u00f4ng \u0111u\u1ee3c thay th\u1ebf nhanh b\u1edfi l\u1edbp kh\u00f4ng kh\u00ed m\u1edbi, c\u00f2n l\u1ea1nh. C\u00f2n khi gi\u00f3 m\u1ea1nh, th\u00ec trong m\u1ed9t ph\u00fat, c\u00e0ng c\u00f3 nhi\u1ec1u kh\u00f4ng kh\u00ed \u0111\u1ebfn ti\u1ebfp x\u00fac v\u1edbi da th\u1ecbt ta v\u00e0 do \u0111\u00f3 th\u00e2n th\u1ec3 ta c\u00e0ng b\u1ecb l\u1ea5y \u0111i nhi\u1ec1u nhi\u1ec7t. Ch\u1ec9 m\u1ed9t \u0111i\u1ec1u \u0111\u00f3 th\u00f4i c\u0169ng \u0111\u1ee7 g\u00e2y ra c\u1ea3m gi\u00e1c l\u1ea1nh. Nhung, h\u00e3y c\u00f2n m\u1ed9t nguy\u00ean nh\u00e2n kh\u00e1c n\u1eefa. Da ch\u00fang ta lu\u00f4n lu\u00f4n b\u1ed1c h\u01a1i \u1ea9m, ngay c\u1ea3 trong kh\u00f4ng kh\u00ed l\u1ea1nh c\u0169ng v\u1eady. \u0110\u1ec3 b\u1ed1c h\u01a1i c\u1ea9n ph\u1ea3i c\u00f3 nhi\u1ec7t lu\u1ee3ng, nhi\u1ec7t \u1ea5y l\u1ea5y t\u1eeb c\u01a1 th\u1ec3 ch\u00fang ta v\u00e0 t\u1eeb l\u1edbp kh\u00f4ng kh\u00ed d\u00ednh s\u00e1t v\u00e0o c\u01a1 th\u1ec3 c\u1ee7a ch\u00fang ta. N\u1ebfu kh\u00f4ng kh\u00ed kh\u00f4ng l\u01b0u th\u00f4ng th\u00ec s\u1ef1 b\u1ed1c h\u01a1i ti\u1ebfn h\u00e0nh r\u1ea5t ch\u1eadm, b\u1edfi v\u00ec l\u1edbp kh\u00f4ng kh\u00ed ti\u1ebfp x\u00fac v\u1edbi da s\u1ebd r\u1ea5t ch\u00f3ng no h\u01a1i nu\u1edbc (b\u00e3o ho\u00e0). Nhung n\u1ebfu kh\u00f4ng kh\u00ed l\u01b0u th\u00f4ng v\u00e0 l\u1edbp kh\u00ed ti\u1ebfp x\u00fac v\u1edbi da lu\u00f4n lu\u00f4n \u0111\u1ed5i m\u1edbi, th\u00ec s\u1ef1 b\u1ed1c h\u01a1i l\u00fac n\u00e0o c\u0169ng ti\u1ebfn h\u00e0nh m\u1ed9t c\u00e1ch m\u1ea1nh m\u1ebd, m\u00e0 nhu v\u1eady c\u01a1 th\u1ec3 s\u1ebd ti\u00eau hao r\u1ea5t nhi\u1ec1u nhi\u1ec7t. V\u1eady t\u00e1c d\u1ee5ng l\u00e0m l\u1ea1nh c\u1ee7a gi\u00f3 l\u1edbn \u0111\u1ebfn m\u1ee9c n\u00e0o? \u0110i\u1ec1u n\u00e0y ph\u1ee5 thu\u1ed9c v\u00e0o v\u1eadn t\u1ed1c c\u1ee7a gi\u00f3 v\u00e0 nhi\u1ec7t \u0111\u1ed9 c\u1ee7a kh\u00f4ng kh\u00ed l\u00fac \u0111\u00f3. N\u00f3i chung, t\u00e1c d\u1ee5ng \u1ea5y vu\u1ee3t xa m\u1ee9c m\u00e0 m\u1ecdi ngu\u1eddi v\u1eabn tu\u1edfng. B\u1ea1n h\u00e3y xem m\u1ed9t v\u00ed d\u1ee5 sau \u0111\u1ec3 c\u00f3 th\u1ec3 h\u00ecnh dung \u0111u\u1ee3c n\u00f3: Gi\u1ea3 s\u1eed nhi\u1ec7t \u0111\u1ed9 c\u1ee7a kh\u00f4ng kh\u00ed l\u00e0 +4 \u0111\u1ed9 C, nhung kh\u00f4ng h\u1ec1 c\u00f3 gi\u00f3. Trong \u0111i\u1ec1u ki\u1ec7n \u1ea5y, nhi\u1ec7t \u0111\u1ed9 c\u1ee7a da ch\u00fang ta l\u00e0 31 \u0111\u1ed9 C. N\u1ebfu b\u00e2y gi\u1edd c\u00f3 m\u1ed9t lu\u1ed3ng gi\u00f3 nh\u1eb9 th\u1ed5i qua, v\u1eeba \u0111\u1ee7 lay \u0111\u1ed9ng l\u00e1 c\u1edd nhung chua \u0111\u1ee7 l\u00e0m rung chuy\u1ec3n l\u00e1 c\u00e2y (kho\u1ea3ng 2 m\/gi\u00e2y), th\u00ec nhi\u1ec7t \u0111\u1ed9 da ch\u00fang ta gi\u1ea3m \u0111i 7 \u0111\u1ed9 C. C\u00f2n khi gi\u00f3 l\u00e0m ng\u1ecdn c\u1edd ph\u1ea5p ph\u1edbi bay (v\u1eadn t\u1ed1c 6 m\/gi\u00e2y) th\u00ec da ch\u00fang ta l\u1ea1nh m\u1ea5t 22 \u0111\u1ed9 , nhi\u1ec7t \u0111\u1ed9 c\u1ee7a da ch\u1ec9 xu\u1ed1ng c\u00f2n 9 \u0111\u1ed9 C. T\u1ea1i sao \u0111\u1ee9ng tr\u00ean cao nh\u00ecn xu\u1ed1ng l\u1ea1i th\u1ea5y ch\u00f3ng m\u1eb7t? \u0110\u1ed1i v\u1edbi c\u01a1 th\u1ec3, \u0111\u1ee9ng t\u1eeb tr\u00ean n\u00f3c nh\u00e0 cao t\u1ea9ng nh\u00ecn xu\u1ed1ng ch\u00ednh l\u00e0 m\u1ed9t lo\u1ea1i k\u00edch th\u00edch b\u1ea5t th\u01b0\u1eddng v\u1edbi c\u01b0\u1eddng \u0111\u1ed9 m\u1ea1nh. N\u00f3 g\u00e2y ra ph\u1ea3n \u1ee9ng theo nhi\u1ec1u \u0111\u01b0\u1eddng kh\u00e1c nhau. Ng\u01b0\u1eddi ta c\u1ea3m th\u1ea5y ch\u00f3ng m\u1eb7t l\u00e0 do nh\u1eefng ph\u1ea3n \u1ee9ng \u0111\u00f3. 1. C\u1ea3nh t\u01b0\u1ee3ng t\u1eeb tr\u00ean cao khi\u1ebfn ch\u00fang ta c\u0103ng th\u1eb3ng: S\u1ef1 c\u0103ng th\u1eb3ng n\u00e0y t\u1ea1o ra h\u00e0ng lo\u1ea1t ph\u1ea3n x\u1ea1 th\u1ea9n kinh, nh\u1ea5t l\u00e0 th\u1ea9n kinh giao c\u1ea3m b\u1ed7ng h\u01b0ng ph\u1ea5n l\u00e0m cho tim \u0111\u1eadp nhanh, ch\u00e2n l\u00f4ng d\u1ef1ng l\u00ean, l\u1ed7 \u0111\u1ed3ng t\u1eed gi\u00e3n ra, ch\u00e2n tay \u0111\u1ed5 m\u1ed3 h\u00f4i, th\u1edf g\u1ea5p, quan tr\u1ecdng h\u01a1n c\u1ea3 l\u00e0 n\u00f3 l\u00e0m co m\u1ea1ch m\u00e1u, huy\u1ebft \u00e1p t\u0103ng \u0111\u1ed9t ng\u1ed9t. Hi\u1ec7n t\u01b0\u1ee3ng n\u00e0y l\u00e0m cho con ng\u01b0\u1eddi ta b\u1ecb ch\u00f3ng m\u1eb7t.","2. L\u00ean cao s\u1ebd b\u1ecb k\u00edch th\u00edch b\u1edfi \u00e1p l\u1ef1c kh\u00f4ng kh\u00ed v\u00e0 ti\u1ebfng gi\u00f3, c\u00f9ng v\u1edbi k\u00edch th\u00edch c\u1ee7a th\u1ecb gi\u00e1c khi nh\u00ecn xu\u1ed1ng: Nh\u1eefng nh\u00e2n t\u1ed1 n\u00e0y s\u1ebd \u1ea3nh h\u01b0\u1edfng \u0111\u1ebfn c\u1ea5u tr\u00fac c\u00e2n b\u1eb1ng trong tai. \u0110i\u1ec1u n\u00e0y l\u00e0m ta nh\u1ea5t th\u1eddi m\u1ea5t \u0111i c\u1ea3m gi\u00e1c th\u0103ng b\u1eb1ng, g\u00e2y ch\u00f3ng m\u1eb7t, th\u1eadm ch\u00ed c\u00f2n c\u00f3 th\u1ec3 n\u00f4n m\u1eeda, gi\u1ed1ng nh\u01b0 say t\u00e0u xe v\u1eady. 3. Ti\u1ec3u n\u00e3o c\u0169ng ph\u1ee5 tr\u00e1ch \u0111\u1ed9ng t\u00e1c c\u00e2n b\u1eb1ng: C\u00e1c k\u00edch th\u00edch khi t\u00e1c \u0111\u1ed9ng m\u1ea1nh v\u00e0o l\u1edbp v\u1ecf \u0111\u1ea1i n\u00e3o, \u201cb\u1ed9 t\u01b0 l\u1ec7nh\u201d th\u1ea9n kinh cao c\u1ea5p nh\u1ea5t c\u1ee7a c\u01a1 th\u1ec3 ng\u01b0\u1eddi, s\u1ebd th\u00f4ng qua th\u1ecb gi\u00e1c, th\u00ednh gi\u00e1c \u0111\u1ec3 t\u00e1c \u0111\u1ed9ng v\u00e0o ti\u1ec3u n\u00e3o, g\u00e2y ra h\u00e0ng lo\u1ea1t ho\u1ea1t \u0111\u1ed9ng \u0111i\u1ec7n sinh h\u1ecdc, l\u00e0m nhi\u1ec5u ch\u1ee9c n\u0103ng ti\u1ec3u n\u00e3o trong th\u1eddi gian ng\u1eafn, khi\u1ebfn ta ch\u00f3ng m\u1eb7t. V\u1eady t\u1ea1i sao l\u00ean t\u1ea9ng cao m\u1edbi c\u00f3 hi\u1ec7n t\u01b0\u1ee3ng n\u00e0y, c\u00f2n l\u00ean n\u00fai cao l\u1ea1i kh\u00f4ng? V\u1ea5n \u0111\u1ec1 r\u1ea5t \u0111\u01a1n gi\u1ea3n. V\u00ec t\u1ea9ng cao l\u00e0 l\u00ean th\u1eb3ng, t\u1ea1o ra s\u1ef1 t\u01b0\u01a1ng ph\u1ea3n \u0111\u1ed9 cao r\u00f5 r\u1ec7t v\u1edbi c\u1ea3nh v\u1eadt xung quanh, do \u0111\u00f3 k\u00edch th\u00edch m\u1ea1nh m\u1ebd h\u01a1n. L\u00ean n\u00fai, d\u00f9 cho n\u00fai cao g\u1ea5p nhi\u1ec1u l\u1ea9n to\u00e0 nh\u00e0, nh\u01b0ng do \u0111\u1ed9 cao c\u1ee7a n\u00f3 thoai tho\u1ea3i, t\u0103ng d\u1ea9n, kh\u00e1c bi\u1ec7t v\u1edbi chung quanh kh\u00f4ng r\u00f5 r\u1ec7t, \u0111\u1ee9ng \u1edf ng\u1ecdn n\u00fai n\u00e0y v\u1eabn th\u1ea5y nhi\u1ec1u ng\u1ecdn n\u00fai kh\u00e1c nh\u1ea5p nh\u00f4, cho n\u00ean kh\u00f4ng t\u1ea1o ra k\u00edch th\u00edch m\u1ea1nh, \u00edt \u1ea3nh h\u01b0\u1edfng \u0111\u1ebfn th\u1ea9n kinh con ng\u01b0\u1eddi. \u0110\u1ed1i v\u1edbi nh\u1eefng ng\u01b0\u1eddi \u00edt khi l\u00ean t\u1ea9ng cao, tr\u01b0\u1edbc khi \u0111i l\u00ean c\u1ea9n chu\u1ea9n b\u1ecb s\u1eb5n s\u00e0ng t\u01b0 t\u01b0\u1edfng, t\u1ed1t nh\u1ea5t n\u00ean ng\u1eafm nh\u00ecn phong c\u1ea3nh \u1edf xa tr\u01b0\u1edbc, l\u00e0m cho th\u1ecb gi\u00e1c, th\u00ednh gi\u00e1c v\u00e0 tinh th\u1ea9n quen d\u1ea9n, r\u1ed3i m\u1edbi thu g\u1ea9n l\u1ea1i v\u00e0 nh\u00ecn th\u1eb3ng xu\u1ed1ng. Nh\u01b0 v\u1eady, ta s\u1ebd kh\u00f4ng b\u1ecb ch\u00f3ng m\u1eb7t. Ch\u00fang ta c\u00f3 th\u1ec3 ch\u1ecbu \u0111\u01b0\u1ee3c n\u00f3ng \u0111\u1ebfn m\u1ee9c n\u00e0o? Kh\u1ea3 n\u0103ng ch\u1ecbu n\u00f3ng c\u1ee7a con ng\u01b0\u1eddi kh\u00e1 h\u01a1n nhi\u1ec1u so v\u1edbi ch\u00fang ta v\u1eabn t\u01b0\u1edfng. T\u1ea1i mi\u1ec1n trung Australia, nhi\u1ec7t \u0111\u1ed9 m\u00f9a h\u00e8 \u1edf ch\u1ed7 r\u00e2m th\u01b0\u1eddng l\u00e0 46 \u0111\u1ed9 C, cao \u0111i\u1ec3m t\u1edbi 56 \u0111\u1ed9 C. C\u00f2n n\u1ebfu t\u0103ng th\u1eadt t\u1eeb t\u1eeb, c\u01a1 th\u1ec3 ng\u01b0\u1eddi th\u1eadm ch\u00ed c\u00f2n ch\u1ecbu \u0111\u01b0\u1ee3c. nhi\u1ec7t \u0111\u1ed9 s\u00f4i c\u1ee7a n\u01b0\u1edbc. Khi t\u00e0u b\u00e8 \u0111i t\u1eeb H\u1ed3ng H\u1ea3i \u0111\u1ebfn v\u1ecbnh Ba T\u01b0, m\u1eb7c d\u00f9 trong c\u00e1c ph\u00f2ng c\u1ee7a t\u00e0u lu\u00f4n lu\u00f4n c\u00f3 qu\u1ea1t th\u00f4ng gi\u00f3, nhi\u1ec7t \u0111\u1ed9 \u1edf \u0111\u00e2y v\u1eabn t\u1edbi 50 \u0111\u1ed9 C ho\u1eb7c h\u01a1n. M\u1ee9c n\u00f3ng nh\u1ea5t quan s\u00e1t trong gi\u1edbi t\u1ef1 nhi\u00ean \u1edf tr\u00ean m\u1eb7t \u0111\u1ea5 kh\u00f4ng qu\u00e1 57 \u0111\u1ed9 C. Nhi\u1ec7t \u0111\u1ed9 n\u00e0y \u0111\u01b0\u1ee3c x\u00e1c \u0111\u1ecbnh t\u1ea1i \u201cthung l\u0169ng ch\u1ebft\u201d thu\u1ed9c California (B\u1eafc M\u1ef9). Tuy nhi\u00ean, nh\u1eefng nhi\u1ec7t \u0111\u1ed9 k\u1ec3 tr\u00ean \u0111\u1ec1u \u0111\u01b0\u1ee3c \u0111o trong b\u00f3ng r\u00e2m. T\u1ea1i sao c\u00e1c nh\u00e0 kh\u00ed t\u01b0\u1ee3ng l\u1ea1i ph\u1ea3i ch\u1ecdn v\u1ecb tr\u00ed nh\u01b0 v\u1eady? \u0110\u00f3 l\u00e0 v\u00ec, ch\u1ec9 khi nhi\u1ec7t k\u1ebf \u0111\u1eb7t trong b\u00f3ng r\u00e2m m\u1edbi \u0111o \u0111\u01b0\u1ee3c nhi\u1ec7t \u0111\u1ed9 c\u1ee7a kh\u00f4ng kh\u00ed. N\u1ebfu \u0111\u1ec3 nhi\u1ec7t k\u1ebf ngo\u00e0i n\u1eafng, M\u1eb7t tr\u1eddi s\u1ebd hun n\u00f3 nhi\u1ec1u h\u01a1n h\u1eb3n so v\u1edbi kh\u00f4ng kh\u00ed xung quanh, th\u00e0nh ra \u0111\u1ed9 ch\u1ec9 c\u1ee7a n\u00f3 kh\u00f4ng cho ta bi\u1ebft ch\u00fat g\u00ec v\u1ec1 tr\u1ea1ng th\u00e1i nhi\u1ec7t c\u1ee7a m\u00f4i tr\u01b0\u1eddng. \u0110\u00e3 c\u00f3 ng\u01b0\u1eddi ti\u1ebfn h\u00e0nh th\u00ed nghi\u1ec7m \u0111\u1ec3 x\u00e1c \u0111\u1ecbnh nhi\u1ec7t \u0111\u1ed9 cao nh\u1ea5t m\u00e0 c\u01a1 th\u1ec3 ng\u01b0\u1eddi c\u00f3 th\u1ec3 ch\u1ecbu \u0111\u1ef1ng \u0111\u01b0\u1ee3c. H\u1ecd nh\u1eadn th\u1ea5y trong kh\u00f4ng kh\u00ed kh\u00f4 r\u00e1o, n\u1ebfu t\u0103ng nhi\u1ec7t \u0111\u1ed9 th\u1eadt t\u1eeb t\u1eeb th\u00ec c\u01a1 th\u1ec3 c\u1ee7a ch\u00fang ta ch\u1eb3ng nh\u1eefng c\u00f3 th\u1ec3 ch\u1ecbu \u0111\u1ef1ng \u0111\u01b0\u1ee3c nhi\u1ec7t \u0111\u1ed9 s\u00f4i c\u1ee7a n\u01b0\u1edbc (100 \u0111\u1ed9 C), m\u00e0 \u0111\u00f4i khi c\u00f2n ch\u1ecbu \u0111\u01b0\u1ee3c nhi\u1ec7t \u0111\u1ed9 cao h\u01a1n n\u1eefa, \u0111\u1ebfn 160 \u0111\u1ed9 C. Hai nh\u00e0 v\u1eadt l\u00fd ng\u01b0\u1eddi Anh l\u00e0 Blag\u01a1den v\u00e0 Tsent\u01a1ri \u0111\u00e3 ch\u1ee9ng minh \u0111i\u1ec1u n\u00e0y b\u1eb1ng c\u00e1ch \u0111\u1ee9ng","h\u00e0ng gi\u1edd trong l\u00f2 n\u01b0\u1edbng b\u00e1nh m\u00ec n\u00f3ng b\u1ecfng. T\u1ea1i sao con ng\u01b0\u1eddi c\u00f3 n\u0103ng l\u1ef1c ch\u1ecbu n\u00f3ng cao \u0111\u1ebfn v\u1eady? \u0110\u00f3 l\u00e0 v\u00ec tr\u00ean th\u1ef1c t\u1ebf, c\u01a1 th\u1ec3 ng\u01b0\u1eddi kh\u00f4ng ti\u1ebfp nh\u1eadn nhi\u1ec7t l\u01b0\u1ee3ng \u0111\u00f3, m\u00e0 v\u1eabn gi\u1eef th\u00e2n nhi\u1ec7t g\u1ea9n v\u1edbi nhi\u1ec7t \u0111\u1ed9 ti\u00eau chu\u1ea9n. C\u01a1 th\u1ec3 ch\u00fang ta ch\u1ed1ng c\u1ef1 l\u1ea1i l\u01b0\u1ee3ng nhi\u1ec7t \u0111\u1ed9 \u0111\u00f3 b\u1eb1ng c\u00e1ch \u0111\u1ed5 m\u1ed3 h\u00f4i. Khi m\u1ed3 h\u00f4i bay h\u01a1i, n\u00f3 s\u1ebd h\u00fat r\u1ea5t nhi\u1ec1u nhi\u1ec7t \u1edf l\u1edbp kh\u00f4ng kh\u00ed d\u00ednh s\u00e1t v\u1edbi da, v\u00e0 l\u00e0m cho nhi\u1ec7t \u0111\u1ed9 c\u1ee7a l\u1edbp kh\u00f4ng kh\u00ed \u1ea5y gi\u1ea3m \u0111i r\u1ea5t nhi\u1ec1u. \u0110i\u1ec1u ki\u1ec7n c\u1ea9n thi\u1ebft duy nh\u1ea5t gi\u00fap cho c\u01a1 th\u1ec3 ngu\u1eddi c\u00f3 th\u1ec3 ch\u1ecbu \u0111\u1ef1ng \u0111u\u1ee3c nhi\u1ec7t \u0111\u1ed9 cao l\u00e0 c\u01a1 th\u1ec3 ngu\u1eddi kh\u00f4ng ti\u1ebfp x\u00fac tr\u1ef1c ti\u1ebfp v\u1edbi ngu\u1ed3n nhi\u1ec7t v\u00e0 kh\u00f4ng kh\u00ed ph\u1ea3i kh\u00f4 r\u00e1o. \u1ede Trung \u00c1, tr\u1eddi n\u00f3ng 37 \u0111\u1ed9 m\u00e0 v\u1eabn tu\u01a1ng \u0111\u1ed1i d\u1ec5 ch\u1ecbu. Nhung n\u1ebfu \u1edf SaintPeterburg n\u00f3ng 24 \u0111\u1ed9 th\u00ec ch\u00fang ta \u0111\u00e3 c\u1ea3m th\u1ea5y kh\u00f3 ch\u1ecbu. Nguy\u00ean nh\u00e2n \u1edf \u0111\u00e2y l\u00e0 do \u0111\u1ed9 \u1ea9m kh\u00f4ng kh\u00ed \u1edf Saint Peterburg cao, c\u00f2n \u0111\u1ed9 \u1ea9m \u1edf Trung \u00c1 th\u00ec th\u1ea5p h\u01a1n do \u1edf \u0111\u00e2y r\u1ea5t \u00edt mua, kh\u00ed h\u1eadu kh\u00f4 r\u00e1o h\u01a1n. Ch\u1ec9 s\u1ed1 IQ kh\u00f4ng ph\u1ea3i l\u00e0 th\u01b0\u1edbc \u0111o tr\u00ed th\u00f4ng minh Nhi\u1ec1u thi\u00ean t\u00e0i to\u00e1n h\u1ecdc c\u00f3 th\u1ec3 nhanh ch\u00f3ng t\u00ecm ra m\u1ed1i li\u00ean h\u1ec7 logic gi\u1eefa c\u00e1c d\u00e3y s\u1ed1 d\u00e0i d\u1eb1ng d\u1eb7c ch\u1ec9 trong v\u00f2ng v\u00e0i gi\u00e2y nhung l\u1ea1i loay hoay c\u1ea3 gi\u1edd \u0111\u1ed3ng h\u1ed3 tru\u1edbc m\u1ed9t c\u00e1i v\u00f2i nu\u1edbc \u0111\u00e3 v\u1eb7n ch\u1eb7t m\u00e0 v\u1eabn r\u1ec9 nu\u1edbc... Anh ta c\u0169ng kh\u00f4ng th\u1ec3 c\u1ea3m nh\u1eadn \u0111u\u1ee3c \u00fd ngh\u0129a th\u1ef1c th\u1ee5 c\u1ee7a m\u1ed9t c\u00e2u th\u01a1 th\u1eadm ch\u00ed c\u0169ng kh\u00f4ng th\u1ec3 t\u00ecm ra \u0111u\u1ee3c m\u1ed9t l\u1eddi n\u00e0o \u0111\u1ec3 an \u1ee7i m\u1ed9t ngu\u1eddi b\u1ea1n trong c\u01a1n ho\u1ea1n n\u1ea1n. Nhung anh ta v\u1eabn l\u00e0 m\u1ed9t thi\u00ean t\u00e0i v\u1edbi tr\u00ed th\u00f4ng minh kh\u00e1c thu\u1eddng. Do \u0111\u00f3, tr\u00ed th\u00f4ng minh l\u00e0 m\u1ed9t kh\u00e1i ni\u1ec7m v\u00f4 c\u00f9ng ph\u1ee9c t\u1ea1p, n\u00f3 kh\u00f4ng th\u1ec3 ch\u1ec9 \u0111u\u1ee3c ki\u1ec3m ch\u1ee9ng th\u00f4ng qua m\u1ed9t v\u00e0i b\u1ed9 c\u00e2u h\u1ecfi ph\u1ee9c t\u1ea1p. Tr\u00ean th\u1ef1c t\u1ebf, nh\u1eefng b\u00e0i tr\u1eafc nghi\u1ec7m ch\u1ec9 s\u1ed1 IQ ch\u1ec9 c\u00f3 t\u00e1c d\u1ee5ng ki\u1ec3m tra kh\u1ea3 n\u0103ng tu duy logic v\u00e0 \u00f3c ph\u00e2n t\u00edch c\u1ee7a m\u1ed7i ngu\u1eddi ch\u1ee9 kh\u00f4ng th\u1ec3 cho ph\u00e9p \u0111\u00e1nh gi\u00e1 m\u1ed9t c\u00e1ch \u0111\u1ea9y \u0111\u1ee7 m\u1ee9c \u0111\u1ed9 th\u00f4ng minh c\u1ee7a ngu\u1eddi \u0111\u00f3 \u0111u\u1ee3c. M\u1ed7i m\u1ed9t con ngu\u1eddi l\u00e0 m\u1ed9t th\u1ef1c th\u1ec3 k\u1ebft h\u1ee3p nhi\u1ec1u d\u1ea1ng bi\u1ec3u hi\u1ec7n kh\u00e1c nhau c\u1ee7a tr\u00ed th\u00f4ng minh m\u00e0 tu\u1ef3 t\u1eebng c\u00e1 nh\u00e2n s\u1ebd c\u00f3 kh\u1ea3 n\u0103ng v\u1ec1 m\u1eb7t n\u00e0y n\u1ed5i tr\u1ed9i h\u01a1n m\u1eb7t kh\u00e1c. N\u00f3i c\u00e1ch kh\u00e1c, tr\u00ed th\u00f4ng minh c\u1ee7a con ngu\u1eddi kh\u00f4ng ch\u1ec9 l\u00e0 kh\u1ea3 n\u0103ng tu duy logic m\u00e0 c\u00f2n c\u00f3 th\u1ec3 l\u00e0 kh\u1ea3 n\u0103ng th\u1ec3 hi\u1ec7n nh\u1eefng c\u1eed ch\u1ec9, \u0111\u1ed9ng t\u00e1c \u0111i\u00eau luy\u1ec7n c\u1ee7a m\u1ed9t v\u0169 c\u00f4ng, kh\u1ea3 n\u0103ng di\u1ec5n \u0111\u1ea1t ng\u00f4n ng\u1eef xu\u1ea5t th\u1ea9n c\u1ee7a m\u1ed9t nh\u00e0 v\u0103n, nh\u00e0 th\u01a1 hay kh\u1ea3 n\u0103ng hi\u1ec3u th\u1ea5u \u0111u\u1ee3c t\u00e2m tu ho\u1eb7c n\u1ed7i l\u00f2ng c\u1ee7a m\u1ed9t ngu\u1eddi n\u00e0o \u0111\u00f3. Tu\u01a1ng t\u1ef1 nhu v\u1eady, m\u1ed9t nh\u1ea1c c\u00f4ng \u0111i\u00eau luy\u1ec7n c\u0169ng l\u00e0 m\u1ed9t ngu\u1eddi r\u1ea5t th\u00f4ng minh trong vi\u1ec7c c\u1ea3m th\u1ee5 \u00e2m nh\u1ea1c hay m\u1ed9t nh\u00e0 h\u00e0ng h\u1ea3i c\u0169ng \u0111u\u1ee3c coi l\u00e0 m\u1ed9t ngu\u1eddi c\u00f3 tr\u00ed th\u00f4ng minh tuy\u1ec7t v\u1edbi trong vi\u1ec7c x\u00e1c \u0111\u1ecbnh phu\u01a1ng hu\u1edbng. C\u0169ng gi\u1ed1ng nh\u01b0 c\u01a1 b\u1eafp, tr\u00ed \u00f3c c\u0169ng c\u1ea9n \u0111\u01b0\u1ee3c nu\u00f4i d\u01b0\u1ee1ng v\u00e0 r\u00e8n luy\u1ec7n th\u01b0\u1eddng xuy\u00ean \u0111\u1ec3 n\u00e2ng cao hi\u1ec7u qu\u1ea3. Tuy nhi\u00ean, r\u00e8n luy\u1ec7n v\u00e0 n\u00e2ng cao tr\u00ed th\u00f4ng minh kh\u00f4ng c\u00f3 ngh\u0129a l\u00e0 c\u1ed1 g\u1eafng nh\u1eadp t\u00e2m h\u00e0ng m\u1edb c\u00e1c d\u00e3y s\u1ed1 hay k\u00fd t\u1ef1 ph\u1ee9c t\u1ea1p nh\u01b0 c\u00e1c danh b\u1ea1 \u0111i\u1ec7n tho\u1ea1i hay s\u1ed1 bi\u1ec3n \u0111\u0103ng k\u00fd c\u1ee7a c\u00e1c xe qua l\u1ea1i tr\u00ean \u0111\u01b0\u1eddng. \u0110\u00f3 c\u00f3 th\u1ec3 \u0111\u01a1n gi\u1ea3n l\u00e0","vi\u1ec7c \u0111\u1ecdc m\u1ed9t cu\u1ed1n s\u00e1ch, ch\u01a1i m\u1ed9t v\u00e1n c\u1edd hay th\u1eadm ch\u00ed tham gia m\u1ed9t s\u1ed1 ho\u1ea1t \u0111\u1ed9ng ch\u00e2n tay c\u00f3 \u0111\u00f2i h\u1ecfi \u00f3c quan s\u00e1t. Nh\u01b0ng t\u1ed1t h\u01a1n h\u1ebft l\u00e0 n\u00ean th\u1eed h\u1ecdc c\u00e1ch ch\u01a1i m\u1ed9t th\u1ee9 g\u00ec \u0111\u00f3 ho\u00e0n to\u00e0n m\u1edbi m\u1ebb, ch\u1eb3ng h\u1ea1n t\u1eadp ch\u01a1i m\u1ed9t m\u00f4n th\u1ec3 thao, h\u1ecdc m\u1ed9t ngo\u1ea1i ng\u1eef, h\u1ecdc v\u1ebd hay t\u1eadp ch\u01a1i c\u1edd. Nh\u1eefng th\u1eed th\u00e1ch m\u1edbi nh\u01b0 v\u1eady \u0111\u1ed1i v\u1edbi b\u1ed9 n\u00e3o s\u1ebd gi\u00fap ch\u1ea5t x\u00e1m t\u1ea1o ra nh\u1eefng m\u1ed1i li\u00ean k\u1ebft m\u1edbi gi\u1eefa c\u00e1c n\u01a1ron v\u00e0 tr\u00e1nh \u0111\u01b0\u1ee3c hi\u1ec7n t\u01b0\u1ee3ng x\u01a1 c\u1ee9ng. Gi\u1ea3i m\u00e3 hi\u1ec7n t\u01b0\u1ee3ng \u1ea3o \u1ea3nh v\u1ec1 th\u00e1c n\u01b0\u1edbc \u0110\u00f3 l\u00e0 m\u1ed9t \u1ea3o gi\u00e1c \u0111\u00e3 l\u00e0m r\u1ed1i tr\u00ed nhi\u1ec1u ng\u01b0\u1eddi t\u1eeb khi Aristotle mi\u00ean t\u1ea3 n\u00f3 kho\u1ea3ng 2.000 n\u0103m tr\u01b0\u1edbc \u0111\u00e2y. N\u1ebfu b\u1ea1n nh\u00ecn v\u00e0o th\u00e1c n\u01b0\u1edbc trong m\u1ed9t th\u1eddi gian ng\u1eafn r\u1ed3i nh\u00ecn sang m\u1ed9t b\u00ean, h\u00ecnh \u1ea3nh b\u00ean b\u1edd \u0111\u00f3 s\u1ebd ch\u1ea3y ng\u01b0\u1ee3c l\u00ean. M\u1ed9t th\u1eed nghi\u1ec7m tr\u00ean n\u00e3o kh\u1ec9 \u0111\u00e3 gi\u1ea3i th\u00edch \u201chi\u1ec7u \u1ee9ng th\u00e1c n\u01b0\u1edbc\u201d n\u00e0y. Khi theo d\u00f5i m\u1ed9t th\u00e1c n\u01b0\u1edbc, c\u00e1c t\u1ebf b\u00e0o n\u00e3o nh\u1eb1m v\u00e0o s\u1ef1 chuy\u1ec3n \u0111\u1ed9ng \u0111i xu\u1ed1ng s\u1ebd tr\u1edf n\u00ean m\u1ec7t m\u1ecfi. Khi m\u1eaft chuy\u1ec3n h\u01b0\u1edbng kh\u00e1c, t\u1ebf b\u00e0o h\u01b0\u1edbng v\u00e0o h\u00e0nh \u0111\u1ed9ng \u0111i l\u00ean s\u1ebd ho\u1ea1t \u0111\u1ed9ng t\u00edch c\u1ef1c h\u01a1n, v\u00e0 do v\u1eady l\u00e0m v\u1eadt th\u1ec3 t\u0129nh d\u01b0\u1eddng nh\u01b0 ch\u1ea3y ng\u01b0\u1ee3c l\u00ean. C\u00e1c nh\u00e0 khoa h\u1ecdc th\u1ea9n kinh \u0111\u00e3 s\u1eed d\u1ee5ng m\u1ed9t m\u00f4 h\u00ecnh t\u01b0\u01a1ng t\u1ef1 \u0111\u1ec3 ch\u1ee9ng minh \u0111i\u1ec1u n\u00e0y. H\u1ecd chi\u1ebfu m\u1ed9t lo\u1ea1t h\u00ecnh \u1ea3nh chuy\u1ec3n \u0111\u1ed9ng cho kh\u1ec9 xem, v\u00e0 thu l\u1ea1i ho\u1ea1t \u0111\u1ed9ng c\u1ee7a h\u1ec7 th\u1ea9n kinh n\u00e3o, trong trung t\u00e2m x\u1eed l\u00fd chuy\u1ec3n \u0111\u1ed9ng. Khi kh\u1ec9 \u0111\u01b0\u1ee3c xem h\u00ecnh \u1ea3nh c\u00e1c \u0111\u01b0\u1eddng th\u1eb3ng ch\u1ea1y d\u1ecdc xu\u1ed1ng, c\u00e1c t\u1ebf b\u00e0o n\u00e3o t\u1eadp trung v\u00e0o chuy\u1ec3n \u0111\u1ed9ng \u0111i xu\u1ed1ng tr\u1edf n\u00ean ph\u1ea3n \u1ee9ng ch\u1eadm d\u1ea9n h\u01a1n, trong khi t\u1ebf b\u00e0o nh\u1eb1m v\u00e0o ho\u1ea1t \u0111\u1ed9ng \u0111i l\u00ean l\u1ea1i kh\u00f4ng b\u1ecb \u1ea3nh h\u01b0\u1edfng. Sau \u0111\u00f3, c\u00e1c nh\u00e0 nghi\u00ean c\u1ee9u cho kh\u1ec9 xem th\u00eam hai h\u00ecnh \u1ea3nh chuy\u1ec3n \u0111\u1ed9ng n\u1eefa -m\u1ed9t g\u1ed3m c\u00e1c \u0111\u01b0\u1eddng th\u1eb3ng \u0111i l\u00ean v\u00e0 m\u1ed9t g\u1ed3m c\u00e1c \u0111\u01b0\u1eddng th\u1eb3ng \u0111i xu\u1ed1ng. H\u1ec7 th\u1ea9n kinh ph\u1ea3n \u1ee9ng v\u1edbi s\u1ef1 \u0111i l\u00ean ho\u1ea1t \u0111\u1ed9ng t\u00edch c\u1ef1c h\u01a1n, so v\u1edbi nh\u1eefng t\u1ebf b\u00e0o h\u01b0\u1edbng v\u00e0o ho\u1ea1t \u0111\u1ed9ng \u0111i xu\u1ed1ng, do b\u00e2y gi\u1edd \u0111\u00e3 b\u1ecb m\u1ecfi m\u1ec7t. S\u1ef1 m\u1ea5t c\u00e2n b\u1eb1ng ph\u1ea3n \u1ee9ng n\u00e0y t\u1ea1o ra \u1ea3o gi\u00e1c v\u1ec1 s\u1ef1 chuy\u1ec3n \u0111\u1ed9ng ng\u01b0\u1ee3c l\u00ean. Hi\u1ec7n t\u01b0\u1ee3ng \u1ea3o \u1ea3nh n\u00e0y \u0111\u00e3 minh ch\u1ee9ng \u201chi\u1ec7u \u1ee9ng th\u00e1c n\u01b0\u1edbc\u201d. N\u1ebfu b\u1ea1n nh\u00ecn v\u00e0o m\u1ed9t h\u00ecnh \u1ea3nh kh\u00e1c sau khi nh\u00ecn v\u00e0o h\u00ecnh \u1ea3nh chuy\u1ec3n \u0111\u1ed9ng \u0111i xu\u1ed1ng, nh\u1eefng \u0111\u01b0\u1eddng \u0111i xu\u1ed1ng bi\u1ebfn m\u1ea5t v\u00e0 h\u00ecnh \u1ea3nh m\u1edbi d\u01b0\u1eddng nh\u01b0 tr\u00f4i ng\u01b0\u1ee3c l\u00ean. K\u1ebft qu\u1ea3 t\u00ecm ki\u1ebfm n\u00e0y c\u0169ng kh\u1eb3ng \u0111\u1ecbnh m\u1ed9t gi\u1ea3 thuy\u1ebft \u0111\u00e3 \u0111\u01b0\u1ee3c nh\u00e0 t\u00e2m l\u00fd h\u1ecdc ng\u01b0\u1eddi \u0110\u1ee9c SigmundExner \u0111\u01b0a ra v\u00e0o th\u1ebf k\u1ef7 XIX. \u00d4ng cho r\u1eb1ng \u1ea3o \u1ea3nh th\u00e1c n\u01b0\u1edbc l\u00e0 do h\u1ec7 th\u1ea9n kinh n\u00e3o b\u1ecb \u1ea3nh h\u01b0\u1edfng b\u1edfi c\u00e1c h\u01b0\u1edbng \u0111\u1ed1i l\u1eadp c\u1ee7a chuy\u1ec3n \u0111\u1ed9ng. T\u1ea1i sao \u0111\u00e0n \u00f4ng lu\u00f4n b\u1ecb cu\u1ed1n h\u00fat b\u1edfi c\u00f9ng m\u1ed9t m\u1eabu ph\u1ee5 n\u1eef? Tr\u00ean th\u1ef1c t\u1ebf, \u0111i\u1ec1u n\u00e0y kh\u00f4ng ph\u1ea3i l\u00e0 do ng\u1eabu nhi\u00ean. B\u1ea1n s\u1ebd b\u1ecb cu\u1ed1n h\u00fat b\u1edfi nh\u1eefng m\u1eabu ng\u01b0\u1eddi c\u00f3 t\u00ednh t\u01b0\u01a1ng \u0111\u1ed3ng v\u1ec1 di truy\u1ec1n v\u1edbi ch\u00ednh b\u1ea1n. Trong sinh ho\u1ea1t h\u1eb1ng n g\u00e0y, trong giao ti\u1ebfp, b\u1ed9 n\u00e3o c\u1ee7a b\u1ea1n lu\u00f4n lu\u00f4n s\u1eb5n s\u00e0ng ti\u1ebfp nh\u1eadn r\u1ea5t nhi\u1ec1u th\u00f4ng tin ph\u00e1t ra t\u1eeb nhi\u1ec1u ng\u01b0\u1eddi ph\u1ee5 n\u1eef kh\u00e1c nhau \u0111\u1ec3 ph\u00e2n t\u00edch v\u00e0 \u201cth\u1ea9m tra\u201d v\u1ec1 t\u00ednh t\u00ecnh, c\u00e1ch","s\u1ed1ng, t\u00ecnh tr\u1ea1ng s\u1ee9c kho\u1ebb v\u00e0 c\u1ea3 v\u1ec1 nh\u1eefng \u0111\u1eb7c \u0111i\u1ec3m di truy\u1ec1n c\u1ee7a h\u1ecd. V\u00e0 trong s\u1ed1 c\u00e1c ph\u1ee5 n\u1eef \u0111\u00f3, n\u1ebfu may m\u1eafn c\u00f3 m\u1ed9t ng\u01b0\u1eddi t\u01b0\u01a1ng \u0111\u1ed3ng v\u1edbi b\u1ea1n th\u00ec b\u1ea1n s\u1ebd b\u1ecb cu\u1ed1n h\u00fat ngay. N\u00f3i r\u00f5 h\u01a1n l\u00e0 n\u00e3o s\u1ebd ph\u00e2n t\u00edch m\u1ed9t chu\u1ed7i c\u00e1c d\u1eef ki\u1ec7n, trong \u0111\u00f3 m\u1ed9t s\u1ed1 do c\u00e1c pheromone cung c\u1ea5p. Pheromonel\u00e0 ch\u1ea5t ho\u00e1 h\u1ecdc th\u01b0\u1eddng \u0111\u01b0\u1ee3c t\u00ecm th\u1ea5y tr\u00ean b\u1ec1 m\u1eb7t da khi ch\u00fang ta b\u00e0i ti\u1ebft m\u1ed3 h\u00f4i. Ch\u00fang c\u00f3 ch\u1ee9c n\u0103ng ph\u00e1t ra c\u00e1c th\u00f4ng tin b\u00e1o hi\u1ec7u \u0111\u1ec3 truy t\u00ecm m\u1ed9t \u0111\u1ed1i t\u01b0\u1ee3ng t\u01b0\u01a1ng h\u1ee3p. Nh\u01b0ng \u0111\u1ec3 n\u00e3o c\u1ee7a b\u1ea1n c\u00f3 th\u1ec3 nh\u1eadn \u0111\u01b0\u1ee3c c\u00e1c t\u00edn hi\u1ec7u t\u01b0\u01a1ng h\u1ee3p, b\u1ea3n th\u00e2n ng\u01b0\u1eddi ph\u1ee5 n\u1eef \u0111\u00f3 c\u0169ng ph\u1ea3i ti\u1ebfp nh\u1eadn \u0111\u01b0\u1ee3c c\u00e1c t\u00edn hi\u1ec7n t\u1eeb pheromone tr\u00ean c\u01a1 th\u1ec3 c\u1ee7a b\u1ea1n. Do \u0111\u00f3, s\u1ef1 thu h\u00fat mang t\u00ednh ch\u1ea5t hai chi\u1ec1u. N\u1ebfu kh\u00f4ng, m\u1ed9t trong hai ng\u01b0\u1eddi s\u1ebd v\u1eabn d\u1eedng d\u01b0ng. Ngo\u00e0i ra, c\u00e1c pheromone c\u0169ng g\u00f3p ph\u1ea9n l\u00e0m thay \u0111\u1ed5i th\u00e1i \u0111\u1ed9 c\u1ee7a b\u1ea1n. Ch\u00fang s\u1ebd k\u00edch th\u00edch c\u00e1c v\u00f9ng n\u00e3o b\u1ed9 c\u00f3 ch\u1ee9c n\u0103ng \u0111i\u1ec1u khi\u1ec3n h\u00e0nh vi b\u1ea3n n\u0103ng v\u00e0 kh\u01a1i d\u1eady c\u00e1c ph\u1ea3n x\u1ea1 c\u00f3 li\u00ean quan \u0111\u1ebfn vi\u1ec7c sinh s\u1ea3n v\u00e0 duy tr\u00ec n\u00f2i gi\u1ed1ng. V\u00e0 quan tr\u1ecdng h\u01a1n c\u1ea3 l\u00e0 ch\u1ec9 \u00fd ngh\u0129 v\u00f4 th\u1ee9c c\u1ee7a b\u1ea1n m\u1edbi ti\u1ebfp nh\u1eadn \u0111u\u1ee3c c\u00e1c t\u00edn hi\u1ec7u n\u00e0y. Ch\u00fang s\u1ebd b\u00e1o cho b\u1ea1n bi\u1ebft r\u1eb1ng: \u201cC\u00f4 \u1ea5y h\u1ee3p v\u1edbi b\u1ea1n \u0111\u1ea5y!\u201d, ho\u1eb7c \u201cKh\u00f4ng c\u00f3 g\u00ec quan tr\u1ecdng c\u1ea3!\u201d. N\u00f3i t\u00f3m l\u1ea1i, b\u1ea1n \u201cbi\u1ebft\u201d c\u00f4 \u1ea5y, b\u1edfi v\u00ec b\u1ea1n \u0111\u00e3 tr\u1ea3i qua nhi\u1ec1u \u0111\u1eb7c \u0111i\u1ec3m sinh l\u00fd v\u00e0 t\u00e2m l\u00fd c\u1ee7a c\u00f4 \u1ea5y, nhung ch\u1ec9 b\u1eb1ng v\u00f4 th\u1ee9c m\u00e0 th\u00f4i. Th\u1ebf n\u00e0o l\u00e0 hi\u1ec7n t\u01b0\u1ee3ng ng\u01b0\u1eddi t\u1ef1 b\u1ed1c ho\u1ea3? V\u1ecb kh\u00e1ch \u0111\u1ebfn g\u00f5 c\u1eeda nh\u00e0 b\u00e0 Reeser, m\u1ed9t ph\u1ee5 n\u1eef lu\u1ed1ng tu\u1ed5i \u0111\u00e3 v\u1ec1 huu s\u1ed1ng t\u1ea1i bang Florida, M\u1ef9. M\u00e3i kh\u00f4ng th\u1ea5y ai ra, b\u00e0 g\u1ecdi th\u00eam ngu\u1eddi ph\u00e1 c\u1eeda. Trong nh\u00e0, tr\u00ean chi\u1ebfc gh\u1ebf b\u00e0nh, ch\u1ee7 nh\u00e2n \u0111\u00e3 ch\u00e1y th\u00e0nh than, ch\u1ec9 c\u00f2n l\u1ea1i m\u1ed9t b\u00e0n ch\u00e2n \u0111i gi\u00e0y v\u1ea3i, xung quanh, \u0111\u1ed3 \u0111\u1ea1c h\u1ea9u nhu v\u1eabn nguy\u00ean v\u1eb9n. S\u1ef1 vi\u1ec7c n\u00e0y x\u1ea3y ra v\u00e0o n\u0103m 1951. B\u00e0 Reeser ch\u1ec9 l\u00e0 m\u1ed9t trong nhi\u1ec1u tru\u1eddng h\u1ee3p \u0111u\u1ee3c l\u1ecbch s\u1eed ghi nh\u1eadn l\u00e0 n\u1ea1n nh\u00e2n c\u1ee7a c\u00e1i ch\u1ebft r\u1ea5t k\u1ef3 l\u1ea1: t\u1ef1 b\u1ed1c ho\u1ea3 th\u00e0nh than. V\u00e0o n\u0103m 1660, du lu\u1eadn Parist\u1eebng r\u1ed9n l\u00ean v\u1edbi v\u1ee5 ch\u00e1y \u201ct\u1ef1 nhi\u00ean\u201d c\u1ee7a m\u1ed9t ph\u1ee5 n\u1eef nghi\u1ec7n ru\u1ee3u n\u1eb7ng, ch\u1ec9 c\u00f2n l\u1ea1i v\u00e0i \u0111\u1ed1t ng\u00f3n tay v\u00e0 chi\u1ebfc s\u1ecd. \u0110i\u1ec1u l\u1ea1 l\u00e0 trong m\u1ecdi v\u1ee5 ch\u00e1y, c\u00e1c n\u1ea1n nh\u00e2n \u0111\u1ec1u \u0111\u1ec3 l\u1ea1i c\u00e1c d\u1ea5u hi\u1ec7u gi\u1ed1ng nhau: th\u00e2n th\u1ec3 ho\u00e1 than nhung bao gi\u1edd c\u0169ng s\u00f3t l\u1ea1i m\u1ed9t b\u1ed9 ph\u1eadn kh\u00f4ng ch\u00e1y tr\u1ee5i, thu\u1eddng \u0111\u00f3 l\u00e0 c\u1eb3ng ch\u00e2n hay b\u00e0n ch\u00e2n v\u00e0 l\u1ea1i c\u00f2n nguy\u00ean v\u1eb9n \u0111\u1ebfn k\u1ef3 l\u1ea1. Ngu\u1eddi ta kh\u00f4ng hi\u1ec3u l\u1eeda t\u1eeb \u0111\u00e2u ra, v\u00ec xung quanh n\u1ea1n nh\u00e2n, thu\u1eddng \u0111u\u1ee3c t\u00ecm th\u1ea5y trong tu th\u1ebf ng\u1ed3i tr\u00ean gh\u1ebf, l\u1eeda h\u1ea9u nhu kh\u00f4ng g\u00e2y hu h\u1ea1i. Ch\u00ednh v\u00ec v\u1eady, c\u00e1c nh\u00e0 quan s\u00e1t th\u1eddi d\u00f3 kh\u00f4ng ch\u00fat nghi ng\u1edd, m\u1ed9t m\u1ef1c cho r\u1eb1ng l\u1eeda nh\u1ea5t thi\u1ebft ph\u1ea3i kh\u1edfi ph\u00e1t t\u1eeb ph\u1ee7 t\u1ea1n c\u1ee7a n\u1ea1n nh\u00e2n. Kh\u1edfi ph\u00e1t t\u1eeb m\u1ed9t l\u00fd do. kh\u00f4ng r\u00f5 v\u00e0 b\u1ea5t ng\u1edd. V\u00ec th\u1ebf, t\u00ean g\u1ecdi l\u00e0 b\u1ea5y l\u00e2u nay ngu\u1eddi ta v\u1eabn g\u00e1n cho hi\u1ec7n tu\u1ee3ng b\u00ed \u1ea5n tr\u00ean l\u00e0 \u201cV\u1ee5 ch\u00e1y ngu\u1eddi t\u1ef1 ph\u00e1t\u201d. V\u00ec sao ngu\u1eddi c\u00f3 th\u1ec3 t\u1ef1 b\u1ed1c ho\u1ea3? Dapan","C\u00e1c nh\u00e0 khoa h\u1ecdc \u0111\u00e3 nghi\u00ean c\u1ee9u v\u00e0 \u0111\u00e3 \u0111ua ra \u0111u\u1ee3c m\u1ed9t \u0111\u00e1p \u00e1n h\u1ee3p l\u00fd h\u01a1n c\u1ea3. \u0110\u00f3 l\u00e0 hi\u1ec7n tu\u1ee3ng \u201chi\u1ec7u \u1ee9ng \u0111\u00e8n c\u1ea9y\u201d, kh\u00f4ng c\u00f3 ch\u00fat g\u00ec l\u00e0 si\u00eau nhi\u00ean. Theo gi\u1ea3 thuy\u1ebft n\u00e0y, ng\u1ecdn l\u1eeda d\u01b0\u1ee3c truy\u1ec1n lan sang th\u00e2n th\u1ec3 c\u1ee7a n\u1ea1n nh\u00e2n qua m\u1ed9t ngu\u1ed3n b\u00ean ngo\u00e0i, c\u1ee9 th\u1ebf thi\u00eau ch\u00e1y d\u1ea9n d\u1ea9n th\u00e2n th\u1ec3 ng\u01b0\u1eddi \u0111\u00f3 nh\u01b0 m\u1ed9t ng\u1ecdn s\u00e1p ch\u00e1y v\u1eady. \u0110\u1ea1i th\u1ec3, k\u1ecbch b\u1ea3n bao gi\u1edd c\u0169ng nh\u01b0 nhau: B\u1ecb m\u1ed9t s\u1ef1 c\u1ed1 g\u00ec v\u1ec1 tim hay ng\u00e3, m\u1ed9t ng\u01b0\u1eddi t\u1eaft th\u1edf. L\u1eeda, t\u1eeb m\u1ed9t v\u1eadt trung gian l\u00e0 thu\u1ed1c l\u00e1, t\u1ea9u hay m\u1ed9t c\u00e2y \u0111\u00e8n c\u1ea9y, ch\u00e1y lan ra qu\u1ea9n \u00e1o, r\u1ed3i ch\u00e1y \u0111\u1ebfn da v\u00e0 l\u1edbp m\u1ee1 n\u1eb1m ngay d\u01b0\u1edbi da. Ti\u1ebfp x\u00fac v\u1edbi l\u1eeda, m\u1ee1 n\u00e0y tan ra n\u01b0\u1edbc, ch\u1ea3y ra b\u00ean ngo\u00e0i th\u00e2n th\u1ec3, th\u1ea5m v\u00e0o c\u00e1c l\u1ea9n v\u1ea3i ti\u1ebfp x\u00fac v\u1edbi n\u1ea1n nh\u00e2n. Trong ph\u1ea9n l\u1edbn c\u00e1c tr\u01b0\u1eddng h\u1ee3p th\u00ec \u0111\u1ea5y l\u00e0 qu\u1ea5n \u00e1o \u0111ang b\u1eadn tr\u00ean ng\u01b0\u1eddi, \u0111\u1ed3 ph\u1ee7 gh\u1ebf t\u1ef1a tr\u00ean \u0111\u00f3 n\u1ea1n nh\u00e2n \u0111ang ng\u1ed3i. \u0110\u1ed3 v\u1ea3i th\u1ea5m \u01b0\u1edbt m\u1ee1 s\u1ebd ch\u00e1y t\u1eeb t\u1eeb trong nhi\u1ec1u gi\u1edd. S\u1ef1 ch\u00e1y n\u00e0y t\u1ea1o ra v\u00e0 duy tr\u00ec m\u1ed9t ng\u1ecdn l\u1eeda ch\u00e1y \u0111\u01b0\u1ee3m c\u00f3 nhi\u1ec7t \u0111\u1ed9 x\u1ea5p x\u1ec9 600 \u0111\u1ed9 C, n\u00f3 kh\u00f4ng l\u00e0m h\u01b0 h\u1ea1i \u0111\u01b0\u1ee3c to\u00e0n b\u1ed9 c\u0103n ph\u00f2ng m\u00e0 ch\u1ec9 thi\u00eau hu\u1ef7 \u0111\u01b0\u1ee3c x\u00e1c ch\u1ebft tr\u00ean \u0111\u00f3 n\u00f3 \u0111\u01b0\u1ee3c ph\u00e1t sinh ra. S\u1ef1 ch\u00e1y ch\u1eadm k\u00e9o d\u00e0i c\u00f3 th\u1ec3 l\u00e0m h\u01b0 h\u1ea1i m\u1ed9t s\u1ed1 b\u1ed9 ph\u1eadn c\u1ee7a th\u00e2n th\u1ec3, nh\u01b0ng v\u1eabn kh\u00f4ng l\u00e0m ch\u00fang ch\u00e1y th\u00e0nh tro v\u00e0 \u0111\u1ec3 l\u1ea1i m\u1ed9t s\u1ed1 b\u1ed9 ph\u1eadn ho\u00e0n to\u00e0n l\u00e0nh l\u1eb7n. MarkBenecke, b\u00e1c s\u0129 ph\u00e1p y t\u1ea1i \u0110\u1ea1i h\u1ecdc Cologne (\u0110\u1ee9c) gi\u1ea3i th\u00edch: l\u1eeda ch\u1ec9 thi\u00eau hu\u1ef7 c\u00e1c m\u00f4 c\u1ee7a c\u01a1 th\u1ec3 ng\u01b0\u1eddi ch\u1ebft n\u1eb1m ph\u00eda b\u00ean tr\u00ean ng\u1ecdn l\u1eeda. Hai b\u00e0n ch\u00e2n v\u00e0 c\u1eb3ng ch\u00e2n th\u01b0\u1eddng c\u00f2n nguy\u00ean v\u1eb9n l\u00e0 do ch\u00fang n\u1eb1m b\u00ean d\u01b0\u1edbi ng\u1ecdn l\u1eeda. L\u1eeda th\u01b0\u1eddng ch\u00e1y t\u1eeb hai \u0111\u00f9i c\u1ee7a m\u1ed9t ng\u01b0\u1eddi ng\u1ed3i, h\u1ea9u h\u1ebft l\u00e0 nh\u1eefng ng\u01b0\u1eddi gi\u00e1 hay \u0111\u1ee9ng tu\u1ed5i l\u1edbp ng\u01b0\u1eddi d\u1ec5 g\u1eb7p tai bi\u1ebfn v\u1ec1 tim khi\u1ebfn h\u1ecd ph\u1ea3i ng\u1ed3i l\u00ec m\u1ed9t ch\u1ed7 ho\u1eb7c nh\u1eefng ng\u01b0\u1eddi \u0111ang c\u01a1n say r\u01b0\u1ee3u khi th\u1ea3m c\u1ea3nh x\u1ea3y \u0111\u1ebfn. Ch\u00ednh r\u01b0\u1ee3u t\u1ea1o thu\u1eadn l\u1ee3i cho lo\u1ea1i tai n\u1ea1n \u0111\u00f3. Tr\u01b0\u1edbc h\u1ebft, m\u1ed9t ai \u0111\u00f3 khi say th\u00ec \u00edt ch\u00fa \u00fd \u0111\u1ebfn lo\u1ea1i l\u1eeda m\u00e0 h\u1ecd \u0111ang c\u1ea9m trong tay, sau n\u1eefa r\u01b0\u1ee3u g\u00f3p ph\u1ea9n l\u00e0m h\u00ecnh th\u00e0nh m\u00f4 b\u00e9o, c\u00f3 ngh\u0129a m\u1ee1 l\u00e0 ch\u1ea5t \u0111\u1ed1t ch\u00ednh trong c\u00e1c v\u1ee5 ch\u00e1y ch\u1eadm n\u00e0y. R\u00f5 r\u00e0ng, hi\u1ec7n t\u01b0\u1ee3ng ng\u01b0\u1eddi ch\u00e1y \u201ct\u1ef1 nhi\u00ean\u201d hay \u201ct\u1ef1 ph\u00e1t\u201d l\u00e2u nay ch\u1ec9 l\u00e0 huy\u1ec1n tho\u1ea1i ho\u1eb7c huy\u1ec5n ho\u1eb7c, \u0111\u01b0\u1ee3c nu\u00f4i d\u01b0\u1ee1ng b\u1edfi tr\u00e0o l\u01b0u v\u0103n h\u1ecdc kinh d\u1ecb th\u1ebf k\u1ef7 XIX v\u00e0 \u0111\u1eb7c bi\u1ec7t l\u00e0 \u1edf trong c\u00e1c cu\u1ed1n truy\u1ec7n tranh vui c\u1ee7a n\u01b0\u1edbc M\u1ef9 sau n\u00e0y. V\u00ec sao c\u00e1c nh\u00e0 du h\u00e0nh hay m\u1ea5t ng\u1ee7? M\u1ea5t ng\u1ee7 v\u00e0 ng\u1ee7 kh\u00f4ng s\u00e2u l\u00e0 \u201cchuy\u1ec7n th\u01b0\u1eddng ng\u00e0y\u201d c\u1ee7a c\u00e1c nh\u00e0 du h\u00e0nh, nh\u1ea5t l\u00e0 khi h\u1ecd \u1edf tr\u00ean v\u0169 tr\u1ee5 d\u00e0i h\u1ea1n trong \u0111i\u1ec1u ki\u1ec7n kh\u00f4ng tr\u1ecdn l\u01b0\u1ee3ng. Vi\u1ec7c thi\u1ebfu \u0111i c\u00e1c t\u00edn hi\u1ec7u ng\u00e0y \u0111\u00eam c\u0169ng l\u00e0m cho \u0111\u1ed3ng h\u1ed3 sinh h\u1ecdc trong ng\u01b0\u1eddi h\u1ecd bi\u1ebfn m\u1ea5t. Hi\u1ec7n t\u01b0\u1ee3ng n\u00e0y khi\u1ebfn c\u00e1c nh\u00e0 du h\u00e0nh k\u00e9m t\u1ec9nh t\u00e1o v\u00e0 gi\u1ea3m hi\u1ec7u qu\u1ea3 ho\u1ea1t \u0111\u1ed9ng. Trong c\u00e1c \u1ea3nh h\u01b0\u1edfng t\u1edbi \u0111\u1ed3ng h\u1ed3 sinh h\u1ecd, c\u00e1c nh\u00e0 nghi\u00ean c\u1ee9u tin r\u1eb1ng ch\u00ednh \u00e1nh s\u00e1ng \u0111\u1eadp v\u00e0o v\u00f5ng m\u1ea1c c\u1ee7a m\u1eaft d\u00e3 gi\u00fap c\u01a1 th\u1ec3 nh\u1eadn bi\u1ebft \u0111\u01b0\u1ee3c th\u1eddi gian trong ng\u00e0y. M\u1eb7t kh\u00e1c, t\u00ecnh tr\u1ea1ng kh\u00f4ng tr\u1ecdng l\u01b0\u1ee3ng trong v\u0169 tr\u1ee5 c\u0169ng \u0111\u1ed3ng ngh\u0129a v\u1edbi vi\u1ec7c c\u00e1c nh\u00e0 du h\u00e0nh ti\u00eau t\u1ed1n \u00edt n\u0103ng l\u01b0\u1ee3ng h\u01a1n so v\u1edbi \u1edf tr\u00ean Tr\u00e1i \u0111\u1ea5t v\u00e0 v\u00ec th\u1ebf, h\u1ecd c\u0169ng th\u1ea5y \u00edt m\u1ec7t m\u1ecfi h\u01a1n (m\u1ec7t m\u1ecfi l\u00e0 c\u1ea3m gi\u00e1c d\u1ec5 khi\u1ebfn con ng\u01b0\u1eddi bu\u1ed3n ng\u1ee7). \u201cNghi\u00ean c\u1ee9u c\u1ee7a ch\u00fang t\u00f4i cho th\u1ea5y con ng\u01b0\u1eddi c\u1ea9n t\u00ecm c\u00e1ch k\u00edch ho\u1ea1t \u0111\u1ed3ng h\u1ed3","sinh h\u1ecdc trong c\u01a1 th\u1ec3, duy tr\u00ec chu k\u1ef3 hai t\u01b0 gi\u1edd m\u1ed7i ng\u00e0y, n\u1ebfu ch\u00fang ta mu\u1ed1n th\u00e0nh c\u00f4ng v\u1edbi c\u00e1c chuy\u1ebfn bay d\u00e0i h\u1ea1n\u201d, Timothy Monk, Gi\u00e1o s\u01b0 \u0110\u1ea1i h\u1ecdc Pittsburghki\u00eam Tr\u01b0\u1edfng nh\u00f3m nghi\u00ean c\u1ee9u, cho bi\u1ebft. H\u1ecd t\u1eebng theo d\u00f5i gi\u1ea5c ng\u1ee7 c\u1ee7a JerryLinenger, m\u1ed9t nh\u00e0 du h\u00e0nh v\u0169 tr\u1ee5 hi\u1ec7n \u0111\u00e3 ngh\u1ec9 h\u01b0u, trong g\u1ea9n n\u0103m th\u00e1ng \u00f4ng \u1edf tr\u00ean tr\u1ea1m v\u0169 tr\u1ee5 Mir c\u1ee7a Nga v\u00e0o n\u0103m 1997. Trong ba k\u1ef3 (m\u1ed7i k\u1ef3 g\u1ed3m hai tu\u1ea9n), l\u1ea9n l\u01b0\u1ee3t \u1edf nh\u1eefng ng\u00e0y \u0111\u1ea9u ti\u00ean, \u1edf gi\u1eefa v\u00e0 cu\u1ed1i cu\u1ed9c h\u00e0nh tr\u00ecnh, c\u00e1c nh\u00e0 nghi\u00ean c\u1ee9u d\u01b0\u1edbi m\u1eb7t \u0111\u1ea5t \u0111\u00e3 ghi ch\u00e9p l\u1ea1i l\u1ecbch ng\u1ee7 c\u1ee7a Linenger nh\u01b0 gi\u1edd \u1edf tr\u00ean gi\u01b0\u1eddng, th\u1eddi gian th\u1ee9c v\u00e0 th\u1eddi gian ng\u1ee7. Trong khi \u0111\u00f3 \u1edf tr\u00ean tr\u1ea1m, Linenger c\u0169ng t\u1ef1 ghi l\u1ea1i nhi\u1ec7t \u0111\u1ed9 c\u01a1 th\u1ec3, l\u1ecbch ng\u1ee7 c\u1ee7a b\u1ea3n th\u00e2n, \u0111\u00e1nh gi\u00e1 \u0111\u1ed9 t\u1ec9nh t\u00e1o n\u0103m l\u1ea9n m\u1ed7i ng\u00e0y v\u00e0 th\u1ef1c hi\u1ec7n ki\u1ec3m tra m\u1ed9t l\u1ea9n v\u00e0o gi\u1eefa ng\u00e0y. K\u1ebft qu\u1ea3 cho th\u1ea5y, trong nh\u1eefng ng\u00e0y \u0111\u1ea9u ti\u00ean l\u00ean tr\u1ea1m, Linenger tu\u00e2n th\u1ee7 th\u1eddi gian \u0111i ng\u1ee7 v\u00e0 d\u1eady \u0111\u1ec1u \u0111\u1eb7n, nh\u01b0ng sau 4 th\u00e1ng, v\u1edbi vi\u1ec7c m\u1ed7i ng\u00e0y \u0111\u1ec1u c\u00f3 15 l\u1ea9n M\u1eb7t tr\u1eddi m\u1ecdc v\u00e0 15 l\u1ea9n M\u1eb7t tr\u1eddi l\u1eb7n, kh\u00f4ng \u0111\u00e3 \u201cm\u1ea5t c\u1ea3m gi\u00e1c v\u1ec1 ng\u00e0y v\u00e0 \u0111\u00eam\u201d. C\u1ee9 45 ph\u00fat m\u1ed9t l\u1ea9n tr\u1eddi l\u1ea1i t\u1ed1i, v\u00e0 v\u00ec th\u1ebf, nh\u1ecbp sinh h\u1ecdc kh\u00f4ng c\u00f2n n\u1eefa. C\u00e1c nghi\u00ean c\u1ee9u tr\u01b0\u1edbc \u0111\u00e2y c\u0169ng ch\u1ec9 ra r\u1eb1ng nh\u1eefng ng\u01b0\u1eddi b\u1ecb m\u1ea5t chu k\u1ef3 s\u00e1ng t\u1ed1i th\u00f4ng th\u01b0\u1eddng, trong \u0111\u00f3 c\u00f3 ng\u01b0\u1eddi m\u00f9, \u0111\u1ec1u ch\u1ecbu \u1ea3nh h\u01b0\u1edfng c\u1ee7a ch\u1ee9ng m\u1ea5t ng\u1ee7, v\u00e0 th\u1eddi gian ng\u1ee7 ban ng\u00e0y nhi\u1ec1u h\u01a1n ho\u1eb7c vi\u1ec7c th\u1ee9c gi\u1ea5c ban \u0111\u00eam di\u1ec5n ra th\u01b0\u1eddng xuy\u00ean h\u01a1n. Nh\u00f3m c\u1ee7a Monk\u0111\u00e3 th\u1eed nghi\u1ec7m m\u1ed9t lo\u1ea1t ph\u01b0\u01a1ng ph\u00e1p kh\u00e1c nhau \u0111\u1ec3 \u0111i\u1ec1u tr\u1ecb ch\u1ee9ng m\u1ea5t ng\u1ee7 trong v\u0169 tr\u1ee5, trong \u0111\u00f3 c\u00f3 vi\u1ec7c d\u00f9ng thu\u1ed1c ng\u1ee7, d\u00f9ng melatonin(m\u1ed9t lo\u1ea1i ho\u00f3c m\u00f4n do tuy\u1ebfn y\u00ean ti\u1ebft ra \u0111\u1ec3 \u0111i\u1ec1u khi\u1ec3n chu k\u1ef3 ng\u1ee7) v\u00e0 s\u1eed d\u1ee5ng \u00e1nh s\u00e1ng nh\u00e2n t\u1ea1o \u0111\u1ec3 m\u00f4 ph\u1ecfng \u00e1nh s\u00e1ng M\u1eb7t tr\u1eddi. H\u1ecd c\u0169ng \u0111\u1ec1 ngh\u1ecb \u0111i\u1ec1u ch\u1ec9nh vi\u1ec7c s\u1eed d\u1ee5ng \u00e1nh s\u00e1ng trong t\u00e0u kh\u00f4ng gian v\u00e0 s\u1eed d\u1ee5ng c\u00e1c b\u00e0i t\u1eadp \u0111\u1ec3 ch\u1ed1ng l\u1ea1i \u1ea3nh h\u01b0\u1edfng c\u1ee7a t\u00ecnh tr\u1ea1ng kh\u00f4ng tr\u1ecdng l\u01b0\u1ee3ng. T\u1ea1i sao ch\u00fang ta tin v\u00e0o linh h\u1ed3n? Nh\u1eefng cu\u1ed9c n\u00f3i chuy\u1ec7n v\u1edbi linh h\u1ed3n ng\u01b0\u1eddi \u0111\u00e3 khu\u1ea5t c\u00f3 th\u1ec3 ch\u1ec9 l\u00e0 k\u1ebft qu\u1ea3 c\u1ee7a s\u1ef1 s\u1ee3 h\u00e3i hay \u00e1m \u1ea3nh, ch\u1ee9 ch\u1ea3 ph\u1ea3i l\u00e0 cu\u1ed9c g\u1eb7p g\u1ee1 t\u00e2m linh n\u00e0o h\u1ebft. C\u00e1c nh\u00e0 khoa h\u1ecdc cho bi\u1ebft, g\u1ecdi h\u1ed3n ch\u1ec9 l\u00e0 c\u00e1ch m\u00e0 ch\u00fang ta gi\u1ea3i to\u1ea3 mong \u01b0\u1edbc c\u1ee7a m\u00ecnh m\u00e0 th\u00f4i. Gi\u00e1o s\u01b0 t\u00e2m l\u00fd ng\u01b0\u1eddi Anh, Richard Wiseman\u0111\u00e3 t\u00ecm hi\u1ec3u nh\u1eefng th\u00ed nghi\u1ec7m \u201cg\u1ecdi h\u1ed3n\u201d c\u00f3 ki\u1ec3m so\u00e1t. T\u1eeb \u0111\u00f3 \u00f4ng nh\u1eadn th\u1ea5y r\u1eb1ng c\u00f3 r\u1ea5t nhi\u1ec1u c\u00e1ch \u0111\u1ec3 con ng\u01b0\u1eddi c\u00f3 th\u1ec3 gi\u1ea3i m\u00e3 \u0111\u01b0\u1ee3c nh\u1eefng l\u1eddi ph\u00e1n c\u1ee7a c\u00e1c b\u00e0 \u0111\u1ed3ng v\u00e0 g\u00e1n gh\u00e9p cho b\u1ea3n th\u00e2n m\u00ecnh, b\u1ea5t ch\u1ea5p t\u00ecnh ti\u1ebft \u0111\u00f3 c\u00f3 \u0111\u00fang s\u1ef1 th\u1ef1c hay kh\u00f4ng. Wisemancho r\u1eb1ng c\u00f3 th\u1ec3 c\u00f3 m\u1ed9t v\u00e0i chi\u1ebfn l\u01b0\u1ee3c \u0111\u1eb1ng sau nh\u1eefng l\u1eddi \u0111o\u00e1n m\u1ed9ng v\u1ed1n \u0111\u01b0\u1ee3c xem l\u00e0 \u201cch\u00ednh x\u00e1c\u201d c\u1ee7a c\u00e1c b\u00e0 \u0111\u1ed3ng. Tr\u01b0\u1edbc h\u1ebft, con ng\u01b0\u1eddi lu\u00f4n lu\u00f4n c\u00f3 xu h\u01b0\u1edbng tin v\u00e0o nh\u1eefng l\u1eddi b\u00ecnh lu\u1eadn, nh\u1eefng ti\u00ean \u0111o\u00e1n chung chung m\u00e0 h\u1ecd c\u00f3 th\u1ec3 v\u1eadn v\u00e0o m\u00ecnh b\u1ea5t c\u1ee9 khi n\u00e0o h\u1ecd mu\u1ed1n. \u201cT\u00f4i cho","r\u1eb1ng c\u00e1c b\u00e0 \u0111\u1ed3ng kh\u00e1 th\u00e0nh th\u1eadt, nh\u01b0ng con ng\u01b0\u1eddi l\u1ea1i \u0111\u1ecdc \u0111\u01b0\u1ee3c r\u1ea5t nhi\u1ec1u th\u00f4ng tin t\u1eeb nh\u1eefng l\u1eddi b\u00ecnh lu\u1eadn kh\u00e1 m\u01a1 h\u1ed3 \u0111\u00f3 c\u1ee7a h\u1ecd\u201d. Ng\u01b0\u1eddi ta c\u0169ng th\u01b0\u1eddng \u0111\u1ebfn v\u1edbi b\u00e0 \u0111\u1ed3ng l\u00e0 \u0111\u1ec3 t\u00ecm ki\u1ebfm s\u1ef1 y\u00ean l\u00f2ng ho\u1eb7c s\u1ef1 tr\u1ee3 gi\u00fap cho m\u1ed9t giai \u0111o\u1ea1n c\u0103ng th\u1eb3ng trong cu\u1ed9c \u0111\u1eddi m\u00ecnh, nh\u01b0 vi\u1ec7c m\u1edbi b\u1ecb m\u1ea5t ng\u01b0\u1eddi th\u00e2n. \u201cCh\u00fang ta mu\u1ed1n tin r\u1eb1ng nh\u1eefng \u0111i\u1ec1u ph\u00e1n l\u00e0 s\u1ef1 th\u1ef1c, v\u00e0 n\u00f3 \u0111\u00fang v\u1edbi ch\u00fang ta, v\u00ec th\u1ebf ch\u00fang ta s\u1ebd c\u00f3 xu h\u01b0\u1edbng s\u1eb5n l\u00f2ng tr\u1ea3 ti\u1ec1n cho nh\u1eefng l\u1eddi n\u00f3i \u0111\u00fang \u00fd \u0111\u00f3\u201d. M\u1ed9t v\u00ed d\u1ee5 l\u00e0 n\u1ebfu b\u00e0 \u0111\u1ed3ng b\u1ea3o r\u1eb1ng: \u201cc\u00e1c linh h\u1ed3n \u0111ang n\u00f3i chuy\u1ec7n v\u1ec1 m\u1ed9t ph\u1ee5 n\u1eef tr\u1ebb \u0111\u00e3 qua \u0111\u1eddi\u201d, th\u00ec \u0111\u00f3 c\u00f3 th\u1ec3 l\u00e0 m\u1ed9t b\u00e9 g\u00e1i, m\u1ed9t thi\u1ebfu n\u1eef ho\u1eb7c m\u1ed9t ai \u0111\u00f3 \u0111\u00e3 ch\u1ebft \u1edf \u0111\u1ed9 tu\u1ed5i 40, tu\u1ef3 theo nh\u00e2n v\u1eadt m\u00e0 b\u1ea1n mu\u1ed1n ngh\u0129 \u0111\u1ebfn. Ngo\u00e0i ra, ng\u01b0\u1eddi ta th\u01b0\u1eddng c\u00f3 xu h\u01b0\u1edbng nh\u1edb \u201cnh\u1eefng \u0111i\u1ec1u may m\u1eafn\u201d -nh\u1eefng l\u1eddi ph\u00e1n c\u1ee7a b\u00e0 \u0111\u1ed3ng h\u1ee3p v\u1edbi mong mu\u1ed1n c\u1ee7a b\u1ea1n v\u00e0 b\u1ecf qua nh\u1eefng \u0111i\u1ec1u \u201ckh\u00f4ng tr\u00fang \u0111\u00edch\u201d. Kh\u00f4ng ch\u1ec9 c\u00f3 t\u00e2m l\u00fd kh\u00e1ch h\u00e0ng \u1ea3nh h\u01b0\u1edfng \u0111\u1ebfn k\u1ebft qu\u1ea3 c\u1ee7a cu\u1ed9c l\u00ean \u0111\u1ed3ng. C\u00e1c b\u00e0 \u0111\u1ed3ng c\u0169ng ti\u1ebfp nh\u1eadn v\u00e0 ph\u1ea3n \u1ee9ng m\u1ed9t c\u00e1ch m\u1ed9t c\u00e1ch v\u00f4 th\u1ee9c v\u1edbi nh\u1eefng th\u00f4ng tin t\u1eeb ho\u00e0n c\u1ea3nh xung quanh. Ch\u1eb3ng h\u1ea1n, b\u00e0 ta c\u00f3 th\u1ec3 \u0111o\u00e1n m\u00f2 nhu c\u1ea9u c\u1ee7a b\u1ea1n b\u1eb1ng c\u00e1ch \u0111\u1ec3 \u00fd t\u1edbi nh\u1eefng chi ti\u1ebft tinh t\u1ebf nh\u01b0 b\u1ed9 \u0111\u1ed3 m\u00e0 b\u1ea1n \u0111ang m\u1eb7c, hay c\u00e1ch m\u00e0 b\u1ea1n ph\u1ea3n \u1ee9ng v\u1edbi nh\u1eefng c\u00e2u h\u1ecfi c\u1ee7a b\u00e0. T\u1ea5t c\u1ea3 nh\u1eefng \u0111i\u1ec1u \u0111\u00f3 khi\u1ebfn cho cu\u1ed9c l\u00ean \u0111\u1ed3ng h\u1ea9u nh\u01b0 l\u00fac n\u00e0o c\u0169ng \u201cth\u00e0nh c\u00f4ng\u201d Gi\u00e1o s\u01b0 Wiseman\u0111\u00e3 cho th\u1ef1c hi\u1ec7n m\u1ed9t cu\u1ed9c g\u1ecdi h\u1ed3n c\u00f3 ki\u1ec3m so\u00e1t v\u1edbi n\u0103m \u0111\u1ed1i t\u01b0\u1ee3ng v\u00e0 c\u00e1c b\u00e0 \u0111\u1ed3ng, nh\u01b0ng kh\u00f4ng h\u1ec1 t\u00ecm th\u1ea5y b\u1eb1ng ch\u1ee9ng v\u1ec1 kh\u1ea3 n\u0103ng t\u00e2m linh th\u1eadt s\u1ef1. Wiseman cho bi\u1ebft kh\u00f4ng ngh\u0129 r\u1eb1ng h\u1ea9u h\u1ebft c\u00e1c \u00f4ng \u0111\u1ed3ng b\u00e0 c\u1ed1t \u0111\u1ec1u l\u00e0 nh\u1eefng k\u1ebb l\u1eeba \u0111\u1ea3o, nh\u01b0ng v\u00ec con ng\u01b0\u1eddi t\u00ecm ki\u1ebfm \u1edf h\u1ecd s\u1ef1 tr\u1ee3 gi\u00fap v\u1ec1 tinh th\u1ea9n \u0111\u1ec3 v\u01b0\u1ee3t qua t\u00ecnh tr\u1ea1ng m\u1ea5t ng\u01b0\u1eddi th\u00e2n, n\u00ean \u0111i\u1ec1u n\u00e0y c\u00f3 th\u1ec3 l\u00e0 t\u1ed1t c\u0169ng c\u00f3 th\u1ec3 l\u00e0 x\u1ea5u. Khi m\u1ea5t ng\u01b0\u1eddi th\u00e2n, ng\u01b0\u1eddi ta th\u01b0\u1eddng c\u1ea3m th\u1ea5y r\u1ea5t c\u00f4 \u0111\u01a1n, b\u01a1 v\u01a1, v\u00e0 nghi ng\u1edd, do \u0111\u00f3 h\u1ecd s\u1ebd t\u00ecm m\u1ecdi c\u00e1ch \u0111\u1ec3 \u0111\u1ebfn \u0111\u01b0\u1ee3c n\u01a1i m\u00e0 h\u1ecd ngh\u0129 r\u1eb1ng s\u1ebd t\u00ecm ra c\u00e2u tr\u1ea3 l\u1eddi cho m\u00ecnh. \u0110i\u1ec1u quan tr\u1ecdng \u0111\u1ed1i v\u1edbi nh\u1eefng ng\u01b0\u1eddi c\u00f3 tang l\u00e0 h\u00e3y c\u1ea9n tr\u1ecdng khi t\u00ecm ki\u1ebfm s\u1ef1 gi\u00fap \u0111\u1ee1, b\u1edfi c\u00f3 th\u1ec3 \u0111\u00f3 ch\u1ec9 l\u00e0 c\u00fa l\u1eeba ngo\u1ea1n m\u1ee5c m\u00e0 th\u00f4i. Ai c\u00f3 th\u1ec3 \u0111i tr\u00ean than h\u1ed3ng? B\u1ea1n c\u00f3 th\u1ec3 v\u00e0o ph\u00f2ng t\u1eafm h\u01a1i \u1edf nhi\u1ec7t \u0111\u1ed9 90 \u0111\u1ed9 trong v\u00f2ng m\u01b0\u1eddi ph\u00fat nh\u01b0ng l\u1ea1i kh\u00f4ng ch\u1ecbu \u0111\u01b0\u1ee3c khi nh\u00fang tay v\u00e0o n\u01b0\u1edbc n\u00f3ng hay kim lo\u1ea1i \u1edf nhi\u1ec7t \u0111\u1ed9 \u1ea5y. Nh\u1eefng ng\u01b0\u1eddi \u0111i tr\u00ean than h\u1ed3ng ch\u1eb3ng c\u00f3 b\u00ed quy\u1ebft, k\u1ef9 thu\u1eadt n\u00e0o c\u1ea3 m\u00e0 ch\u1ec9 d\u1ef1a v\u00e0o v\u1eadn t\u1ed1c truy\u1ec1n nhi\u1ec7t t\u1eeb v\u1eadt n\u00e0y sang v\u1eadt kh\u00e1c m\u00e0 th\u00f4i. M\u1ed9t v\u1eadt \u0111\u01b0\u1ee3c coi l\u00e0 n\u00f3ng hay kh\u00f4ng n\u00f3ng kh\u00f4ng ch\u1ec9 ph\u1ee5 thu\u1ed9c v\u00e0o nhi\u1ec7t \u0111\u1ed9 c\u1ee7a n\u00f3. Than h\u1ed3ng c\u00f3 th\u1ec3 \u0111\u1ea1t \u0111\u1ebfn 700 \u0111\u1ed9 C nh\u01b0ng v\u1eabn kh\u00f4ng n\u01b0\u1edbng ch\u00edn gan b\u00e0n ch\u00e2n ng\u01b0\u1eddi v\u00ec n\u00f3 d\u1eabn nhi\u1ec7t r\u1ea5t k\u00e9m. Ph\u1ea3i m\u1ea5t hai gi\u00e2y ti\u1ebfp x\u00fac n\u00f3 m\u1edbi truy\u1ec1n sang b\u00e0n ch\u00e2n b\u1ea1n 60 \u0111\u1ed9 C v\u00e0 b\u1eaft \u0111\u1ea9u n\u00f3ng l\u00ean. Do \u0111\u00f3 n\u1ebfu b\u1ea1n b\u01b0\u1edbc nhanh ch\u00e2n tr\u00ean than c\u1ee7i \u0111\u1ecf","r\u1ef1c, s\u1ebd ch\u1eb3ng c\u00f3 g\u00ec nguy hi\u1ec3m c\u1ea3. Nh\u01b0ng b\u1ea1n h\u00e3y nh\u1edb, khi \u0111i tr\u00ean than h\u1ed3ng ph\u1ea3i h\u1ebft s\u1ee9c b\u00ecnh t\u0129nh, kh\u00f4ng th\u00ec nguy hi\u1ec3m l\u1eafm v\u00e0 \u0111\u1eb7c bi\u1ec7t kh\u00f4ng n\u00ean thi gan b\u00e0n ch\u00e2n v\u1edbi than \u0111\u00e1 v\u00ec n\u00f3 d\u1eabn nhi\u1ec7t r\u1ea5t t\u1ed1t. V\u00ec sao th\u1eddi gian tr\u00f4i nhanh h\u01a1n khi ng\u01b0\u1eddi ta vui? C\u00e1c nh\u00e0 khoa h\u1ecdc \u0111\u00e3 gi\u1ea3i th\u00edch \u0111\u01b0\u1ee3c hi\u1ec7n t\u01b0\u1ee3ng th\u1eddi gian tr\u00f4i mau khi t\u00e2m tr\u1ea1ng con ng\u01b0\u1eddi \u0111ang h\u01b0ng ph\u1ea5n, v\u00e0 k\u00e9o d\u00e0i l\u00ea th\u00ea nh\u1eefng l\u00fac b\u1ea1n u s\u1ea9u. Vi\u1ec7c ch\u1ee5p \u1ea3nh n\u00e3o \u0111\u00e3 cho th\u1ea5y nh\u1eefng h\u00ecnh th\u00e1i ho\u1ea1t \u0111\u1ed9ng kh\u00e1c nhau c\u1ee7a n\u00e3o, ph\u1ee5 thu\u1ed9c v\u00e0o m\u1ee9c \u0111\u1ed9 t\u1eadp trung cho c\u00f4ng vi\u1ec7c. N\u1ebfu c\u1ee9 ch\u00fa \u00fd m\u00e3i v\u00e0o vi\u1ec7c th\u1eddi gian s\u1ebd tr\u00f4i \u0111i nh\u01b0 th\u1ebf n\u00e0o nh\u01b0 ch\u00fang ta v\u1eabn l\u00e0m khi bu\u1ed3n r\u1ea9u n\u00e3o s\u1ebd k\u00edch ho\u1ea1t m\u1ed9t d\u1ea1ng ho\u1ea1t \u0111\u1ed9ng khi\u1ebfn ta t\u01b0\u1edfng nh\u01b0 chi\u1ebfc kim \u0111\u1ed3ng h\u1ed3 t\u00edch t\u1eafc ch\u1eadm h\u01a1n. K\u1ebft qu\u1ea3 cho th\u1ea5y m\u1ed9t m\u1ea1ng l\u01b0\u1edbi c\u00e1c v\u00f9ng tr\u00ean n\u00e3o \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 v\u00f9ng v\u00e2n v\u1ecf n\u00e3o (cortico - striatal loop) ho\u1ea1t \u0111\u1ed9ng m\u1ea1nh h\u01a1n khi ng\u01b0\u1eddi tham gia t\u1eadp trung s\u1ef1 ch\u00fa \u00fd v\u00e0o th\u1eddi gian. Theo c\u00e1c nh\u00e0 nghi\u00ean c\u1ee9u, n\u1ebfu n\u00e3o b\u1eadn quan t\u00e2m t\u1edbi nhi\u1ec1u kh\u00eda c\u1ea1nh kh\u00e1c nhau c\u1ee7a c\u00f4ng vi\u1ec7c, n\u00f3 s\u1ebd ph\u1ea3i d\u00e0n tr\u1ea3i ngu\u1ed3n t\u00e0i nguy\u00ean \u00edt \u1ecfi c\u1ee7a m\u00ecnh, v\u00e0 d\u00e0nh s\u1ef1 ch\u00fa \u00fd khi\u00eam t\u1ed1n cho th\u1eddi gian. V\u00ec th\u1ebf nh\u1eefng gi\u1edd ph\u00fat qua \u0111i m\u00e0 ch\u00fang ta g\u1ea9n nh\u01b0 kh\u00f4ng nh\u1eadn th\u1ea5y, v\u00e0 c\u1ea3m gi\u00e1c d\u01b0\u1eddng nh\u01b0 n\u00f3 tr\u00f4i nhanh h\u01a1n. Tuy nhi\u00ean, n\u1ebfu n\u00e3o kh\u00f4ng b\u1ecb k\u00edch th\u00edch theo c\u00e1ch n\u00e0y, n\u00f3 s\u1ebd t\u1eadp trung to\u00e0n b\u1ed9 tinh l\u1ef1c v\u00e0o vi\u1ec7c theo d\u00f5i di\u1ec5n ti\u1ebfn c\u1ee7a th\u1eddi gian. \u0110i\u1ec1u \u0111\u00f3 khi\u1ec3n ta c\u1ea3m th\u1ea5y nh\u01b0 th\u1eddi gian l\u00ea ch\u1eadm ch\u1ea1p, trong khi c\u00f3 th\u1ec3 \u0111\u00e2y m\u1edbi ch\u00ednh l\u00e0 s\u1ef1 nh\u1eadn th\u1ee9c ch\u00ednh x\u00e1c. S\u1ef1 gi\u1ed1ng nhau c\u1ee7a nhi\u1ec1u v\u00f9ng tr\u00ean n\u00e3o c\u00f9ng tham gia \u01b0\u1edbc l\u01b0\u1ee3ng th\u1eddi gian l\u00e0 \u1edf ch\u1ed7, ch\u00fang \u0111\u1ec1u \u0111\u00f3ng vai tr\u00f2 quan tr\u1ecdng trong vi\u1ec7c ki\u1ec3m so\u00e1t chuy\u1ec3n \u0111\u1ed9ng, v\u00e0 chu\u1ea9n b\u1ecb cho nh\u1eefng ho\u1ea1t \u0111\u1ed9ng m\u1edbi, gi\u1ed1ng nh\u01b0 khi m\u1ed9t nh\u1ea1c s\u1ef9 gi\u1eadm ch\u00e2n, ho\u1eb7c m\u1ed9t v\u1eadn \u0111\u1ed9ng vi\u00ean \u0111o\u00e1n \u0111\u1ee3i ti\u1ebfng c\u00f2i c\u1ee7a tr\u1ecdng t\u00e0i. V\u00ec sao ch\u1ec9 c\u00f3 con ng\u01b0\u1eddi bi\u1ebft n\u00f3i? Trong khi kh\u1ec9 c\u00f3 th\u1ec3 hi\u1ec3u \u0111\u01b0\u1ee3c nh\u1eefng quy lu\u1eadt c\u01a1 b\u1ea3n v\u1ec1 t\u1eeb, ch\u00fang l\u1ea1i kh\u00f4ng th\u1ec3 n\u1eafm \u0111\u01b0\u1ee3c c\u00e1c quy lu\u1eadt ph\u1ee9c t\u1ea1p h\u01a1n trong c\u00e1c c\u1ea5u tr\u00fac ng\u1eef ph\u00e1p. Ch\u1ec9 c\u00f3 lo\u00e0i ng\u01b0\u1eddi l\u00e0 v\u01b0\u1ee3t qua \u0111\u01b0\u1ee3c c\u00e1i \u201cn\u00fat c\u1ed5 chai ki\u1ebfn th\u1ee9c\u201d n\u00e0y tr\u00ean con \u0111\u01b0\u1eddng x\u00e2y d\u1ef1ng v\u00e0 s\u1eed d\u1ee5ng nh\u1eefng ng\u00f4n ng\u1eef m\u00e0 th\u00f4i.","Ch\u1eb3ng h\u1ea1n, khi c\u00f3 th\u1ec3 n\u1eafm v\u1eefng nh\u1eefng c\u1ea5u tr\u00fac t\u1eeb \u0111\u01a1n gi\u1ea3n t\u01b0\u01a1ng t\u1ef1 nh\u01b0 vi\u1ec7c nh\u1eadn ra \u201cthe\u201d v\u00e0 \u201ca\u201d lu\u00f4n \u0111\u01b0\u1ee3c theo sau b\u1edfi nh\u1eefng t\u1eeb kh\u00e1c. Nh\u01b0ng ch\u00fang kh\u00f4ng th\u1ec3 hi\u1ec3u \u0111\u01b0\u1ee3c c\u00e1c c\u1ea5u tr\u00fac \u0111i\u1ec1u ki\u1ec7n ph\u1ee9c t\u1ea1p h\u01a1n nh\u01b0: \u201cif_then_\u201d (n\u1ebfu... th\u00ec _____). N\u1ea5c thang ng\u1eef ph\u00e1p n\u00e0y, m\u00e0 t\u1ea5t c\u1ea3 c\u00e1c ng\u00f4n ng\u1eef c\u1ee7a lo\u00e0i ng\u01b0\u1eddi \u0111\u1ec1u ph\u1ee5 thu\u1ed9c, c\u00f3 th\u1ec3 l\u00e0 \u201cn\u00fat c\u1ed5 chai ki\u1ebfn th\u1ee9c quy\u1ebft \u0111\u1ecbnh m\u00e0 ch\u00fang ta ph\u1ea3i \u0111i qua trong qu\u00e1 tr\u00ecnh ph\u00e1t tri\u1ec3n v\u00e0 s\u1eed d\u1ee5ng ng\u00f4n ng\u1eef\u201d. C\u00e1c nh\u00e0 nghi\u00ean c\u1ee9u \u0111\u00e3 th\u1ef1c hi\u1ec7n hai th\u1eed nghi\u1ec7m b\u1eb1ng tai tr\u00ean nh\u1eefng con kh\u1ec9 tamarin \u0111\u1ea9u tr\u1eafng, trong \u0111\u00f3 ng\u01b0\u1eddi ta s\u1ebd \u0111\u1ecdc l\u00ean m\u1ed9t chu\u1ed7i c\u00e1c t\u1eeb m\u1ed9t \u00e2m ti\u1ebft. Trong th\u1eed nghi\u1ec7m \u0111\u1ea9u ti\u00ean, c\u00e1c t\u1eeb ng\u1eabu nhi\u00ean \u0111\u01b0\u1ee3c g\u1ecdi ra theo m\u1ed9t chu\u1ed7i s\u1eafp x\u1ebfp nghi\u00eam ng\u1eb7t: gi\u1ecdng nam tr\u01b0\u1edbc, gi\u1ecdng n\u1eef sau. Nh\u1eefng con kh\u1ec9 \u0111\u00e1p \u1ee9ng v\u1edbi s\u1ef1 thay \u0111\u1ed5i \u0111\u1ed9t ng\u1ed9t trong quy lu\u1eadt nam n\u1eef n\u00e0y b\u1eb1ng c\u00e1ch nh\u00ecn v\u00e0o mi\u1ec7ng ng\u01b0\u1eddi \u0111\u1ecdc. \u0110i\u1ec1u n\u00e0y cho th\u1ea5y ch\u00fang c\u00f3 th\u1ec3 nh\u1eadn ra nh\u1eefng quy lu\u1eadt \u0111\u01a1n gi\u1ea3n. Trong th\u1eed nghi\u1ec7m ti\u1ebfp theo, quy lu\u1eadt ng\u1eef ph\u00e1p \u0111\u01b0\u1ee3c thi\u1ebft l\u1eadp theo ki\u1ec3u gi\u1ecdng nam c\u00f3 th\u1ec3 \u0111\u1ecdc ra m\u1ed9t, hai ho\u1eb7c ba t\u1eeb, r\u1ed3i \u0111\u1ebfn gi\u1ecdng n\u1eef c\u0169ng t\u01b0\u01a1ng t\u1ef1 nh\u01b0 v\u1eady. Lo\u1ea1i th\u1eed nghi\u1ec7m n\u00e0y ph\u1ee9c t\u1ea1p h\u01a1n m\u1ed9t ch\u00fat, \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 s\u1ef1 l\u1ed3ng di\u1ec5n, v\u00ec n\u00f3 li\u00ean quan t\u1edbi vi\u1ec7c t\u1ed3n t\u1ea1i m\u1ed9t quy lu\u1eadt trong m\u1ed9t quy lu\u1eadt kh\u00e1c. L\u00fac n\u00e0y, nh\u1eefng con kh\u1ec9 kh\u00f4ng th\u1ec3 nh\u1eadn ra b\u1ea5t k\u1ef3 s\u1ef1 thay \u0111\u1ed5i n\u00e0o trong chu\u1ed7i t\u1eeb. Tuy nhi\u00ean, khi con ng\u01b0\u1eddi \u0111\u01b0\u1ee3c th\u1eed nghi\u1ec7m t\u01b0\u01a1ng t\u1ef1 l\u1ea1i kh\u00f4ng g\u1eb7p kh\u00f3 kh\u0103n nh\u01b0 v\u1eady, m\u1eb7c d\u00f9 h\u1ea9u h\u1ebft h\u1ecd kh\u00f4ng th\u1ec3 gi\u1ea3i th\u00edch th\u1ef1c s\u1ef1 quy lu\u1eadt \u0111\u00f3 l\u00e0 g\u00ec. \u201cKh\u1ea3 n\u0103ng nh\u1eadn bi\u1ebft s\u1ef1 l\u1ed3ng di\u1ec5n l\u00e0 \u0111\u1ed9c nh\u1ea5t \u1edf ng\u01b0\u1eddi v\u00e0 \u1ea3nh h\u01b0\u1edfng kh\u00f4ng ch\u1ec9 t\u1edbi ng\u00f4n ng\u1eef m\u00e0 c\u00f2nt\u1edbi h\u1ea9u h\u1ebft c\u00e1c h\u00e0nh vi c\u1ee7a ch\u00fang ta\u201d, c\u00e1c chuy\u00ean gia ng\u00f4n ng\u1eef linh tr\u01b0\u1edfng cho bi\u1ebft. \u201cCh\u1eb3ng h\u1ea1n, trong l\u1edbp h\u1ecdc, ch\u00fang ta th\u01b0\u1eddng nh\u00ecn th\u1ea5y em A nh\u00ecn em B, em B nh\u00ecn em C, v\u00e0 em C nh\u00ecn th\u1ea9y gi\u00e1o. Nh\u01b0ng trong h\u1ecd nh\u00e0 tinh tinh, ch\u00fang ta th\u1ea5y kh\u1ec9 A nh\u00ecn m\u1eb9 n\u00f3, kh\u1ec9 B nh\u00ecn m\u1eb9 n\u00f3, kh\u1ec9 C nh\u00ecn m\u1eb9 n\u00f3...\u201d Kh\u1ea3 n\u0103ng l\u1ed3ng di\u1ec5n kh\u00f4ng ho\u00e0n to\u00e0n c\u1ea9n thi\u1ebft cho ng\u00f4n ng\u1eef b\u1edfi v\u00ec ch\u00fang ta c\u00f2n n\u00f3i c\u1ea3 nh\u1eefng c\u00e2u \u0111\u01a1n ngh\u0129a -nh\u01b0ng kh\u1ea3 n\u0103ng hi\u1ec3u \u0111\u01b0\u1ee3c nh\u1eefng c\u00e2u n\u00f3i \u1ea9n \u00fd c\u00f3 th\u1ec3 l\u00e0 m\u1ed9t tr\u1edf ng\u1ea1i khi\u1ebfn cho kh\u1ec9 kh\u00f4ng th\u1ec3 ph\u00e1t tri\u1ec3n \u0111\u01b0\u1ee3c ti\u1ebfng n\u00f3i. \u201cKh\u1ec9 kh\u00f4ng nh\u1eefng kh\u00f4ng th\u1ec3 n\u00f3i \u0111\u01b0\u1ee3c, ch\u00fang c\u00f2n kh\u00f4ng th\u1ec3 b\u1eaft ch\u01b0\u1edbc \u0111\u00fang c\u00e1c h\u00e0nh \u0111\u1ed9ng v\u00e0 kh\u00f4ng th\u1ec3 d\u1ea1y l\u1ea1i l\u00e0 nh\u1eefng k\u1ef9 n\u0103ng c\u1ea9n thi\u1ebft cho ng\u00f4n ng\u1eef\u201d. Kh\u1ea3 n\u0103ng n\u1eafm v\u1eefng c\u00e1c quy lu\u1eadt \u1ea9n ng\u1eef l\u00e0 ch\u00eca kho\u00e1 cho s\u1ef1 linh \u0111\u1ed9ng c\u1ee7a lo\u00e0i ng\u01b0\u1eddi, cho ph\u00e9pcon ng\u01b0\u1eddi t\u01b0 duy tr\u1eebu t\u01b0\u1ee3ng, s\u1eed d\u1ee5ng ph\u00e9p \u1ea9n d\u1ee5 v\u00e0 nh\u1eefng kh\u00e1i ni\u1ec7m bao h\u00e0m nh\u01b0 th\u1eddi gian. C\u00f3 ph\u1ea3i lo\u00e0i ng\u01b0\u1eddi v\u00e0 lo\u00e0i kh\u1ec9 c\u00f3 c\u00f9ng \u201cd\u00f2ng h\u1ecd\u201d?","X\u00e9t v\u1ec1 h\u00ecnh d\u00e1ng b\u00ean ngo\u00e0i th\u00ec lo\u00e0i kh\u1ec9 c\u00f3 r\u1ea5t nhi\u1ec1u n\u00e9t gi\u1ed1ng v\u1edbi con ng\u01b0\u1eddi. Ch\u1ec9 c\u1ea9n x\u00e9t \u0111\u00f4i b\u00e0n tay c\u1ee7a kh\u1ec9 c\u0169ng \u0111\u1ee7 th\u1ea5y r\u00f5 -n\u00f3 ch\u1eb3ng kh\u00e1c tay ng\u01b0\u1eddi ch\u00fat n\u00e0o. C\u0169ng n\u0103m ng\u00f3n, tr\u00ean c\u00e1c ng\u00f3n tay c\u0169ng c\u00f3 \u0111\u1ea9y \u0111\u1ee7 m\u00f3ng. V\u1ec1 khu\u00f4n m\u1eb7t c\u0169ng c\u00f3 nhi\u1ec1u n\u00e9t t\u01b0\u01a1ng \u0111\u1ed3ng: c\u0169ng bi\u1ebft bu\u1ed3n vui nh\u01b0 con ng\u01b0\u1eddi. C\u00f2n v\u1ec1 kh\u1ed1i \u00f3c v\u00e0 tr\u00ed tu\u1ec7 c\u1ee7a kh\u1ec9 n\u1eefa. C\u00f3 l\u1ebd \u0111\u00e2y m\u1edbi l\u00e0 nh\u1eefng b\u1eb1ng ch\u1ee9ng c\u01a1 b\u1ea3n v\u1ec1 vi\u1ec7c n\u00f3 c\u00f3 ph\u1ea3i l\u00e0 h\u1ecd h\u00e0ng, b\u00e0 con v\u1edbi lo\u00e0i ng\u01b0\u1eddi. Th\u1ef1c ra th\u00ec b\u1ed9 \u00f3c c\u1ee7a lo\u00e0i H\u1eafc tinh tinh nh\u1ecf h\u01a1n \u00f3c c\u1ee7a con ng\u01b0\u1eddi t\u1edbi ba l\u1ea9n (b\u1ed9 \u00f3c to nh\u1ea5t c\u1ee7a ch\u00fang l\u00e0 700 cm2), nh\u01b0ng c\u00e1c r\u00e3nh v\u00e0 c\u00e1c n\u1ebfp nh\u0103n trong \u0111\u00f3 th\u00ec l\u1ea1i kh\u00f4ng ph\u1ea3i l\u00e0 \u00edt. Ch\u1eb3ng c\u00f3 \u0111i\u1ec1u g\u00ec \u0111\u00e1ng ng\u1ea1c nhi\u00ean h\u1ebft: kh\u1ec9 c\u0169ng c\u00f3 tr\u00ed tu\u1ec7. N\u00f3 c\u0169ng ph\u1ea3i \u201c\u0111\u1ed9ng n\u00e3o\u201d lu\u00f4n. Th\u1eed h\u1ecfi c\u00f3 lo\u00e0i v\u1eadt n\u00e0o \u0111o\u00e1n ra \u0111\u01b0\u1ee3c l\u00e0 mu\u1ed1n v\u1edbi \u0111\u01b0\u1ee3c qu\u1ea3 chu\u1ed1i tr\u00ean cao th\u00ec ph\u1ea3i l\u1ea5y m\u1ea5y c\u00e1i h\u1ed9p x\u00e2y th\u00e0nh b\u1ee5c m\u00e0 tr\u00e8o l\u00ean. Song n\u00f3i cho c\u00f9ng th\u00ec t\u1ea5t c\u1ea3 m\u1ecdi \u0111i\u1ec1u \u0111o m\u1edbi ch\u1ec9 l\u00e0 nh\u1eefng b\u1eb1ng ch\u1ee9ng \u201cgi\u00e1n ti\u1ebfp\u201d v\u1ec1 quan h\u1ec7 h\u1ecd h\u00e0ng c\u1ee7a lo\u00e0i ng\u01b0\u1eddi v\u00e0 lo\u00e0i kh\u1ec9 m\u00e0 th\u00f4i. Ch\u00fang ta \u0111ang c\u00f2n c\u00f3 nh\u1eefng \u0111i\u1ec3m tr\u1ef1c ti\u1ebfp kh\u00e1c n\u1eefa. C\u00f3 l\u1ea9n ng\u01b0\u1eddi ta \u0111\u00e3 \u0111em m\u00e1u c\u1ee7a con ng\u01b0\u1eddi th\u1eed ti\u1ebfp cho con chim b\u1ed3 c\u00e2u. Con chim b\u1ed3 c\u00e2u ch\u1ebft. Ti\u1ebfp cho th\u1ecf, th\u1ecf l\u0103n ra \u1ed1m. Nh\u01b0ng khi \u0111em m\u00e1u c\u1ee7a con ng\u01b0\u1eddi ti\u1ebfp cho H\u1eafc tinh tinh th\u00ec th\u1ea5y n\u00f3 kh\u00f4ng vi\u1ec7c g\u00ec c\u1ea3. Nh\u01b0 v\u1eady c\u00e1c nh\u00e0 khoa h\u1ecdc \u0111\u00e3 \u0111\u00fang khi li\u1ec7t con ng\u01b0\u1eddi v\u00e0 nh\u1eefng con v\u01b0\u1ee3n h\u00ecnh ng\u01b0\u1eddi v\u00e0o nh\u00f3m \u0111\u1ed9ng v\u1eadt thu\u1ed9c h\u1ecd Linh tr\u01b0\u1edfng. B\u1edfi vi\u1ec7c ti\u1ebfp m\u00e1u ch\u1ec9 c\u00f3 k\u1ebft qu\u1ea3 t\u1ed1t \u0111\u1eb9p chi ng\u01b0\u1eddi hi\u1ebfn m\u00e1u v\u00e0 ng\u01b0\u1eddi \u0111\u01b0\u1ee3c ti\u1ebfp m\u00e1u c\u00f3 c\u00f9ng nh\u00f3m m\u00e1u. C\u00e1ch \u0111\u00e2y ch\u01b0a l\u00e2u ng\u01b0\u1eddi ta \u0111\u00e3 m\u1ea1o hi\u1ec3m \u0111em m\u00e1u v\u01b0\u1ee3n ti\u1ebfp cho ng\u01b0\u1eddi n\u1eefa. H\u00e0ng ch\u1ee5c cu\u1ed9c ti\u1ebfp m\u00e1u nh\u01b0 v\u1eady \u0111\u00e3 \u0111\u01b0\u1ee3c ti\u1ebfn h\u00e0nh v\u00e0 \u0111\u1ec1u th\u00e0nh c\u00f4ng c\u1ea3. Ngay c\u1ea3 \u0111\u1ebfn k\u00fd sinh tr\u00f9ng c\u1ee7a c\u1ea3 hai gi\u1ed1ng c\u0169ng nh\u01b0 nhau. C\u1ea3 b\u1ec7nh t\u1eadt c\u0169ng gi\u1ed1ng nhau: ho lao, ung th\u01b0, t\u1ee5 huy\u1ebft, l\u1ef5, t\u0103ng huy\u1ebft \u00e1p, x\u01a1 \u0111\u1ed9ng m\u1ea1ch. t\u1ea5t c\u1ea3 \u0111\u1ec1u l\u00e0 nh\u1eefng c\u0103n b\u1ec7nh chung v\u00e0 ph\u1ed5 bi\u1ebfn; v\u00e0 \u1edf ng\u01b0\u1eddi l\u1eabn kh\u1ec9 \u0111\u1ec1u c\u00f3 Nh\u01b0ng s\u1ebd l\u00e0 sai l\u1ea9m n\u1ebfu ta cho r\u1eb1ng nh\u1eefng con v\u01b0\u1ee3n h\u00ecnh ng\u01b0\u1eddi hi\u1ec7n nay ch\u00ednh l\u00e0 t\u1ed5 ti\u00ean c\u1ee7a ch\u00fang ta. Kh\u00f4ng ph\u1ea3i nh\u01b0 v\u1eady \u0111\u00e2u. V\u1ea5n \u0111\u1ec1 t\u1ed5 ti\u00ean nh\u00e2n lo\u1ea1i hi\u1ec7n nay \u0111ang c\u00f2n nhi\u1ec1u \u0111i\u1ec3m ch\u01b0a s\u00e1ng t\u1ecf. Tuy v\u1eady c\u00f3 m\u1ed9t \u0111i\u1ec3m m\u00e0 h\u1ea9u h\u1ebft c\u00e1c nh\u00e0 khoa h\u1ecdc \u0111\u1ec1u nh\u1ea5t tr\u00ed l\u00e0 kh\u00f4ng n\u00ean t\u00ecm t\u1ed5 ti\u00ean c\u1ee7a ch\u00fang ta trong nh\u1eefng con kh\u1ec9 hi\u1ec7n th\u1eddi. Ch\u00fang ta v\u00e0 lo\u00e0i v\u01b0\u1ee3n h\u00ecnh ng\u01b0\u1eddi ch\u1ec9 c\u00f9ng chung m\u1ed9t s\u1ed1 t\u1ed5 ti\u00ean c\u1ed5 lai hy m\u00e0 th\u00f4i. Nh\u1eefng th\u00ed nghi\u1ec7m \u201c\u0111\u1eb9p nh\u1ea5t\u201d trong l\u1ecbch s\u1eed Nh\u1eefng th\u00ed nghi\u1ec7m khoa h\u1ecdc hi\u1ec7n nay th\u01b0\u1eddng ph\u1ee9c t\u1ea1p, ch\u1ec9 c\u00f3 th\u1ec3 th\u1ef1c hi\u1ec7n b\u1edfi","m\u1ed9t nh\u00f3m nghi\u00ean c\u1ee9u, v\u1edbi chi ph\u00ed l\u00ean t\u1edbi h\u00e0ng tri\u1ec7u USD. Tuy nhi\u00ean, khi \u0111\u01b0\u1ee3c h\u1ecfi v\u1ec1 th\u00ed nghi\u1ec7m \u201c\u0111\u1eb9p nh\u1ea5t\u201d trong l\u1ecbch s\u1eed khoa h\u1ecdc, ng\u01b0\u1eddi ta l\u1ea1i t\u00f4n s\u00f9ng c\u00e1c \u00fd t\u01b0\u1edfng \u0111\u01a1n gi\u1ea3n. M\u1edbi \u0111\u00e2y, ti\u1ebfn s\u0129 Robert Crease, thu\u1ed9c khoa tri\u1ebft c\u1ee7a \u0110\u1ea1i h\u1ecdc NewYork (M\u1ef9), \u0111\u00e3 l\u00e0m m\u1ed9t cu\u1ed9c th\u0103m d\u00f2 \u00fd ki\u1ebfn c\u1ee7a c\u00e1c nh\u00e0 khoa h\u1ecdc v\u1ec1 \u201cth\u00ed nghi\u1ec7m \u0111\u1eb9p nh\u1ea5t trong l\u1ecbch s\u1eed\u201d. K\u1ebft qu\u1ea3, kh\u00f4ng ph\u1ea3i nh\u1eefng th\u00ed nghi\u1ec7m hi\u1ec7n \u0111\u1ea1i v\u00e0 ph\u1ee9c t\u1ea1p (v\u1ec1 ph\u00e2n t\u00edch gene, v\u1ec1 h\u1ea1t h\u1ea1 nguy\u00ean t\u1eed hay \u0111o \u00e1nh s\u00e1ng c\u1ee7a c\u00e1c ng\u00f4i sao xa...) \u0111\u01b0\u1ee3c ch\u1ecdn l\u00e0 \u201c\u0111\u1eb9p nh\u1ea5t\u201d, m\u00e0 ch\u00ednh l\u00e0 nh\u1eefng th\u00ed nghi\u1ec7m \u0111\u01a1n gi\u1ea3n nh\u01b0 \u0111o chu vi Tr\u00e1i \u0111\u1ea5t, t\u00e1n x\u1ea1 \u00e1nh s\u00e1ng, v\u1eadt r\u01a1i t\u1ef1 do., \u0111\u01b0\u1ee3c ng\u01b0\u1eddi ta y\u00eau th\u00edch h\u01a1n c\u1ea3. V\u1ebb \u0111\u1eb9p n\u00e0y c\u00f3 m\u1ed9t \u00fd ngh\u0129a r\u1ea5t c\u1ed5 \u0111i\u1ec3n: m\u00f4 h\u00ecnh th\u00ed nghi\u1ec7m \u0111\u01a1n gi\u1ea3n, logic \u0111\u01a1n gi\u1ea3n, nh\u01b0ng k\u1ebft qu\u1ea3 \u0111\u1ea1t \u0111\u01b0\u1ee3c l\u1ea1i r\u1ea5t l\u1edbn. D\u01b0\u1edbi \u0111\u00e2y l\u00e0 th\u1ee9 t\u1ef1 c\u00e1c th\u00ed nghi\u1ec7m \u0111\u01b0\u1ee3c xem l\u00e0 \u201c\u0111\u1eb9p nh\u1ea5t\u201d (x\u1ebfp theo th\u1ee9 t\u1ef1 th\u1eddi gian). Th\u00ed nghi\u1ec7m \u0111o \u0111\u01b0\u1eddng k\u00ednh Tr\u00e1i \u0111\u1ea5t c\u1ee7a Erasthenes V\u00e0o m\u1ed9t ng\u00e0y h\u1ea1 ch\u00ed c\u00e1ch \u0111\u00e2y kho\u1ea3ng 2300 n\u0103m, t\u1ea1i th\u00e0nh ph\u1ed1 Awan c\u1ee7a Ai C\u1eadp, Erasthenes \u0111\u00e3 x\u00e1c \u0111\u1ecbnh \u0111\u01b0\u1ee3c th\u1eddi \u0111i\u1ec3m m\u00e0 \u00e1nh s\u00e1ng M\u1eb7t tr\u1eddi chi\u1ebfu th\u1eb3ng \u0111\u1ee9ng xu\u1ed1ng b\u1ec1 m\u1eb7t \u0111\u1ea5t. C\u00f3 ngh\u0129a l\u00e0 b\u00f3ng c\u1ee7a m\u1ed9t chi\u1ebfc c\u1ecdc th\u1eb3ng \u0111\u1ee9ng tr\u00f9ng kh\u1edbp v\u1edbi th\u00e2n c\u1ecdc. C\u00f9ng th\u1eddi \u0111i\u1ec3m \u0111\u00f3 n\u0103m sau, \u00f4ng \u0111\u00e3 \u0111o b\u00f3ng c\u1ee7a m\u1ed9t chi\u1ebfc c\u1ecdc \u0111\u1eb7t \u1edf Alexandria (Hy L\u1ea1p), v\u00e0 ph\u00e1t hi\u1ec7n ra r\u1eb1ng, \u00e1nh s\u00e1ng M\u1eb7t tr\u1eddi nghi\u00eang 7 \u0111\u1ed9 so v\u1edbi ph\u01b0\u01a1ng th\u1eb3ng \u0111\u1ee9ng. Gi\u1ea3 \u0111\u1ecbnh r\u1eb1ng Tr\u00e1i \u0111\u1ea5t l\u00e0 h\u00ecnh c\u1ea9u, th\u00ec chu vi c\u1ee7a n\u00f3 t\u01b0\u01a1ng \u1ee9ng v\u1edbi m\u1ed9t g\u00f3c 360 \u0111\u1ed9. N\u1ebfu hai th\u00e0nh ph\u1ed1 (Awan v\u00e0 Alexandria) c\u00e1ch nhau m\u1ed9t g\u00f3c 7 \u0111\u1ed9, th\u00ec g\u00f3c \u0111\u00f3 ph\u1ea3i t\u01b0\u01a1ng \u1ee9ng v\u1edbi kho\u1ea3ng c\u00e1ch gi\u1eefa hai th\u00e0nh ph\u1ed1 \u1ea5y (v\u1edbi gi\u1ea3 \u0111\u1ecbnh r\u1eb1ng c\u1ea3 hai th\u00e0nh ph\u1ed1 c\u00f9ng n\u1eb1m tr\u00ean \u0111\u01b0\u1eddng x\u00edch \u0111\u1ea1o). D\u1ef1a v\u00e0o m\u1ed1i li\u00ean h\u1ec7 n\u00e0y, Erasthenes \u0111\u00e3 t\u00ednh ra chu vi Tr\u00e1i \u0111\u1ea5t l\u00e0 250.000 stadia. \u0110\u1ebfn nay, ng\u01b0\u1eddi ta v\u1eabn ch\u01b0a bi\u1ebft ch\u00ednh x\u00e1c 1 stadia theo chu\u1ea9n Hy L\u1ea1p l\u00e0 bao nhi\u00eau m\u00e9t (c\u00f3 th\u1ec3 l\u00e0 chi\u1ec1u d\u00e0i c\u1ee7a m\u1ed9t s\u00e2n v\u1eadn \u0111\u1ed9ng?), n\u00ean ch\u01b0a th\u1ec3 c\u00f3 k\u1ebft lu\u1eadn v\u1ec1 \u0111\u1ed9 ch\u00ednh x\u00e1c trong th\u00ed nghi\u1ec7m c\u1ee7a Erasthenes. Tuy nhi\u00ean, ph\u01b0\u01a1ng ph\u00e1p c\u1ee7a \u00f4ng ho\u00e0n to\u00e0n h\u1ee3p l\u00fd v\u1ec1 m\u1eb7t logic. N\u00f3 cho th\u1ea5y, Erasthenes kh\u00f4ng nh\u1eefng \u0111\u00e3 bi\u1ebft Tr\u00e1i \u0111\u1ea5t h\u00ecnh c\u1ea9u, m\u00e0 c\u00f2n hi\u1ec3u v\u1ec1 chuy\u1ec3n \u0111\u1ed9ng c\u1ee7a n\u00f3 quanh M\u1eb7t tr\u1eddi. Th\u00ed nghi\u1ec7m v\u1ec1 v\u1eadt r\u01a1i t\u1ef1 do c\u1ee7a Galilei Cu\u1ed1i th\u1ebf k\u1ef7 XVI, ng\u01b0\u1eddi ta \u0111\u1ec1u tin r\u1eb1ng, v\u1eadt th\u1ec3 n\u1eb7ng \u0111\u1ec1u r\u01a1i nhanh h\u01a1n v\u1eadt th\u1ec3 nh\u1eb9. L\u00fd do l\u00e0 Aristotle \u0111\u00e3 n\u00f3i nh\u01b0 v\u1eady, v\u00e0 quan \u0111i\u1ec3m \u0111\u00f3 \u0111\u01b0\u1ee3c Nh\u00e0 th\u1edd c\u00f4ng nh\u1eadn Tuy nhi\u00ean Galileo Galilei, m\u1ed9t th\u1ea9y gi\u00e1o d\u1ea1y to\u00e1n \u1edf \u0110\u1ea1i h\u1ecdc Pisa (Italy) l\u1ea1i tin v\u00e0o \u0111i\u1ec1u kh\u00e1c h\u1eb3n. Th\u00ed nghi\u1ec7m v\u1ec1 v\u1eadt r\u01a1i t\u1ef1 do c\u1ee7a \u00f4ng \u0111\u00e3 tr\u1edf th\u00e0nh c\u00e2u chuy\u1ec7n kinh \u0111i\u1ec3n trong khoa h\u1ecdc: \u00d4ng \u0111\u00e3 leo l\u00ean th\u00e1p nghi\u00eang Pisa \u0111\u1ec3 th\u1ea3 c\u00e1c v\u1eadt c\u00f3 kh\u1ed1i l\u01b0\u1ee3ng kh\u00e1c","nhau xu\u1ed1ng \u0111\u1ea5t, v\u00e0 r\u00fat ra k\u1ebft lu\u1eadn l\u00e0 ch\u00fang r\u01a1i v\u1edbi t\u1ed1c \u0111\u1ed9 nh\u01b0 nhau! (t\u1ea5t nhi\u00ean ph\u1ea3i b\u1ecf qua s\u1ee9c c\u1ea3n c\u1ee7a kh\u00f4ng kh\u00ed). V\u00ec k\u1ebft lu\u1eadn n\u00e0y m\u00e0 \u00f4ng \u0111\u00e3 b\u1ecb \u0111u\u1ed5i vi\u1ec7c. \u00d4ng tr\u1edf th\u00e0nh t\u1ea5m g\u01b0\u01a1ng s\u00e1ng cho c\u00e1c nh\u00e0 nghi\u00ean c\u1ee9u sau n\u00e0y, v\u00ec \u0111\u00e3 ch\u1ec9 ra r\u1eb1ng: Ng\u01b0\u1eddi ta ch\u1ec9 c\u00f3 th\u1ec3 r\u00fat ra ki\u1ebfn th\u1ee9c khoa h\u1ecdc t\u1eeb c\u00e1c quy lu\u1eadt kh\u00e1ch quan c\u1ee7a thi\u00ean nhi\u00ean, ch\u1ee9 kh\u00f4ng ph\u1ea3i t\u1eeb ni\u1ec1m tin. Th\u00ed nghi\u1ec7m v\u1ec1 c\u00e1c vi\u00ean bi l\u0103n tr\u00ean m\u1eb7t d\u1ed1c c\u1ee7a Galilei M\u1ed9t l\u1ea9n n\u1eefa, Galileo Galileil\u1ea1i c\u00f3 m\u1ed9t th\u00ed nghi\u1ec7m \u0111\u01b0\u1ee3c l\u1ecdt v\u00e0o \u201cTop 10 th\u00ed nghi\u1ec7m \u0111\u1eb9p nh\u1ea5t\u201d. \u0110\u1ec3 ki\u1ec3m ch\u1ee9ng m\u1ed9t \u0111\u1ea1i l\u01b0\u1ee3ng g\u1ecdi l\u00e0 gia t\u1ed1c, Galilei\u0111\u00e3 thi\u1ebft k\u1ebf m\u1ed9t t\u1ea5m v\u00e1n d\u00e0i 5,5 m\u00e9t, r\u1ed9ng 0,22 m\u00e9t. Sau \u0111\u00f3, \u00f4ng cho x\u1ebb m\u1ed9t r\u00e3nh \u1edf gi\u1eefa t\u1ea5m v\u00e1n... Galilei d\u1ef1ng t\u1ea5m v\u00e1n d\u1ed1c xu\u1ed1ng, r\u1ed3i th\u1ea3 c\u00e1c vi\u00ean bi \u0111\u1ed3ng theo r\u00e3nh. Sau \u0111\u00f3, \u00f4ng d\u00f9ng m\u1ed9t chi\u1ebfc \u0111\u1ed3ng h\u1ed3 n\u01b0\u1edbc \u0111\u1ec3 \u0111o th\u1eddi gian m\u00e0 vi\u00ean bi di chuy\u1ec3n tr\u00ean m\u1ed9t qu\u00e3ng \u0111\u01b0\u1eddng nh\u1ea5t \u0111\u1ecbnh (Galilei\u0111\u00e3 \u0111o \u0111\u01b0\u1eddng \u0111i c\u1ee7a vi\u00ean bi v\u00e0 c\u00e2n s\u1ed1 n\u01b0\u1edbc do \u0111\u1ed3ng h\u1ed3 nh\u1ecf ra \u0111\u1ec3 suy ra t\u1ef7 l\u1ec7 gi\u1eefa \u0111\u01b0\u1eddng \u0111i v\u00e0 th\u1eddi gian di chuy\u1ec3n c\u1ee7a v\u1eadt th\u1ec3). Galileikh\u00e1m ph\u00e1 ra r\u1eb1ng, c\u00e0ng xu\u1ed1ng ch\u00e2n d\u1ed1c, vi\u00ean bi ch\u1ea1y c\u00e0ng nhanh: Qu\u00e3ng \u0111\u01b0\u1eddng \u0111i t\u1ef7 l\u1ec7 thu\u1eadn v\u1edbi b\u00ecnh ph\u01b0\u01a1ng c\u1ee7a th\u1eddi gian di chuy\u1ec3n. L\u00fd do l\u00e0 vi\u00ean bi lu\u00f4n ch\u1ecbu t\u00e1c d\u1ee5ng c\u1ee7a m\u1ed9t gia t\u1ed1c (g\u00e2y ra b\u1edfi l\u1ef1c h\u00fat c\u1ee7a Tr\u00e1i \u0111\u1ea5t). \u0110\u00f3 ch\u00ednh l\u00e0 gia t\u1ed1c t\u1ef1 do (g = 9,8 m\/s2). Newton\u0111\u00e3 ch\u1ee9ng minh r\u1eb1ng, \u00e1nh s\u00e1ng tr\u1eafng b\u1ecb ph\u00e2n t\u00e1n th\u00e0nh nhi\u1ec1u m\u00e0u khi \u0111i qua l\u0103ng k\u00ednh. Tr\u01b0\u1edbc Newton, ng\u01b0\u1eddi ta v\u1eabn cho r\u1eb1ng \u00e1nh s\u00e1ng l\u00e0 m\u1ed9t th\u1ec3 tinh khi\u1ebft, kh\u00f4ng th\u1ec3 ph\u00e2n t\u00e1ch (l\u1ea1i Aristotle!). Tuy nhi\u00ean, Newton\u0111\u00e3 ch\u1ec9 ra sai l\u1ea9m n\u00e0y, khi \u00f4ng d\u00f9ng l\u0103ng k\u00ednh \u0111\u1ec3 t\u00e1ch \u00e1nh s\u00e1ng M\u1eb7t tr\u1eddi ra c\u00e1c m\u00e0u kh\u00e1c nhau r\u1ed3i chi\u1ebfu l\u00ean t\u01b0\u1eddng. Th\u00ed nghi\u1ec7m c\u1ee7a Newtoncho th\u1ea5y, \u00e1nh s\u00e1ng tr\u1eafng kh\u00f4ng h\u1ec1 \u201cnguy\u00ean ch\u1ea5t\u201d m\u00e0 n\u00f3 l\u00e0 t\u1ed5ng h\u1ee3p c\u1ee7a m\u1ed9t d\u1ea3i quang ph\u1ed5 7 m\u00e0u c\u01a1 b\u1ea3n: \u0111\u1ecf, da cam, v\u00e0ng, xanh l\u00e1 c\u00e2y, xanh n\u01b0\u1edbc bi\u1ec3n, ch\u00e0m, t\u00edm. Th\u00ed nghi\u1ec7m v\u1ec1 \u201cs\u1ee3i d\u00e2y xo\u1eafn\u201d c\u1ee7a Cavendish Ch\u00fang ta \u0111\u1ec1u bi\u1ebft r\u1eb1ng Newtonl\u00e0 ng\u01b0\u1eddi t\u00ecm ra l\u1ef1c h\u1ea5p d\u1eabn. \u00d4ng \u0111\u00e3 ch\u1ec9 ra r\u1eb1ng, hai v\u1eadt lu\u00f4n h\u00fat nhau b\u1eb1ng m\u1ed9t l\u1ef1c t\u1ef7 l\u1ec7 thu\u1eadn v\u1edbi kh\u1ed1i l\u01b0\u1ee3ng v\u00e0 t\u1ef7 l\u1ec7 ngh\u1ecbch v\u1edbi b\u00ecnh ph\u01b0\u01a1ng kho\u1ea3ng c\u00e1ch gi\u1eefa ch\u00fang. Tuy nhi\u00ean, l\u00e0m sao \u0111\u1ec3 ch\u1ec9 cho ng\u01b0\u1eddi kh\u00e1c th\u1ea5y l\u1ef1c h\u1ea5p d\u1eabn b\u1eb1ng th\u00ed nghi\u1ec7m (b\u1edfi v\u00ec n\u00f3 qu\u00e1 y\u1ebfu)? Cu\u1ed1i th\u1ebf k\u1ef7 18, nh\u00e0 khoa h\u1ecdc ng\u01b0\u1eddi Anh HenryCanvadish \u0111\u00e3 l\u00e0m m\u1ed9t th\u00ed nghi\u1ec7m tinh x\u1ea3o nh\u01b0 sau: \u00d4ng cho g\u1eafn hai vi\u00ean bi kim lo\u1ea1i v\u00e0o hai \u0111\u1ea9u c\u1ee7a m\u1ed9t thanh g\u1ed7, r\u1ed3i d\u00f9ng m\u1ed9t s\u1ee3i d\u00e2y m\u1ea3nh treo c\u1ea3 h\u1ec7 th\u1ed1ng l\u00ean, sao cho thanh g\u1ed7 n\u1eb1m ngang. Sau \u0111\u00f3,","Cavendish\u0111\u00e3 d\u00f9ng hai qu\u1ea3 c\u1ea9u ch\u00ec, m\u1ed7i qu\u1ea3 n\u1eb7ng 170 kg, t\u1ecbnh ti\u1ebfn l\u1ea1i g\u1ea9n hai vi\u00ean bi \u1edf hai \u0111\u1ea9u g\u1eady. Theo gi\u1ea3 thuy\u1ebft, l\u1ef1c h\u1ea5p d\u1eabn do hai qu\u1ea3 c\u1ea9u ch\u1ec9 t\u00e1c d\u1ee5ng v\u00e0o hai vi\u00ean bi s\u1ebd l\u00e0m cho c\u00e2y g\u1eady quay m\u1ed9t g\u00f3c nh\u1ecf, v\u00e0 s\u1ee3i d\u00e2y s\u1ebd b\u1ecb xo\u1eafn m\u1ed9t v\u00e0i \u0111o\u1ea1n. K\u1ebft qu\u1ea3, th\u00ed nghi\u1ec7m c\u1ee7a Canvadish \u0111\u01b0\u1ee3c x\u00e2y d\u1ef1ng tinh vi \u0111\u1ebfn m\u1ee9c, n\u00f3 ph\u1ea3n \u00e1nh g\u1ea9n nh\u01b0 ch\u00ednh x\u00e1c gi\u00e1 tr\u1ecb c\u1ee7a l\u1ef1c h\u1ea5p d\u1eabn. \u00d4ng c\u0169ng t\u00ednh ra \u0111\u01b0\u1ee3c m\u1ed9t h\u1eb1ng s\u1ed1 h\u1ea5p d\u1eabn g\u1ea9n \u0111\u00fang v\u1edbi h\u1eb1ng s\u1ed1 m\u00e0 ch\u00fang ta bi\u1ebft hi\u1ec7n nay. Th\u1eadm ch\u00ed Canvadish c\u00f2n s\u1eed d\u1ee5ng nguy\u00ean l\u00fd th\u00ed nghi\u1ec7m n\u00e0y \u0111\u1ec3 t\u00ednh ra \u0111\u01b0\u1ee3c kh\u1ed1i l\u01b0\u1ee3ng c\u1ee7a Tr\u00e1i \u0111\u1ea5t l\u00e0 60 x 1020 kg. Th\u00ed nghi\u1ec7m v\u1ec1 s\u1ef1 giao thoa \u00e1nh s\u00e1ng c\u1ee7a Young Nhi\u1ec1u n\u0103m li\u1ec1n, Newton\u0111\u00e3 d\u1eabn c\u00e1c nh\u00e0 khoa h\u1ecdc v\u00e0o m\u1ed9t con \u0111\u01b0\u1eddng sai l\u1ea9m khi \u00f4ng cho r\u1eb1ng \u00e1nh s\u00e1ng \u0111\u01b0\u1ee3c c\u1ea5u th\u00e0nh t\u1eeb h\u1ea1t ch\u1ee9 kh\u00f4ng ph\u1ea3i l\u00e0 s\u00f3ng. Tuy nhi\u00ean, n\u0103m 1803, nh\u00e0 v\u1eadt l\u00fd ng\u01b0\u1eddi Anh Thomas Young\u0111\u00e3 ph\u1ea3n b\u00e1c \u0111\u01b0\u1ee3c quan \u0111i\u1ec3m c\u1ee7a Newtonb\u1eb1ng th\u00ed nghi\u1ec7m sau: Young kho\u00e9t m\u1ed9t l\u1ed7 \u1edf c\u1eeda k\u00ednh, r\u1ed3i che l\u1ea1i b\u1eb1ng m\u1ed9t mi\u1ebfng gi\u1ea5y d\u00e0y, c\u00f3 ch\u00e2m m\u1ed9t l\u1ed7 nh\u1ecf nh\u01b0 \u0111\u1ea9u kim. Sau \u0111\u00f3, Youngd\u00f9ng m\u1ed9t t\u1ea5m g\u01b0\u01a1ng \u0111\u1ec3 l\u00e0m ch\u1ec7ch h\u01b0\u1edfng \u0111i c\u1ee7a tia s\u00e1ng m\u1ea3nh r\u1ecdi qua l\u1ed7 nh\u1ecf c\u1ee7a mi\u1ebfng gi\u1ea5y. Ti\u1ebfp theo, \u00f4ng d\u00f9ng m\u1ed9t m\u1ea3nh b\u00eca c\u1ef1c m\u1ea3nh (c\u1ee1 0,1 milimet) \u0111\u1eb7t v\u00e0o gi\u1eefa tia s\u00e1ng \u0111\u1ec3 t\u00e1ch n\u00f3 ra l\u00e0m hai. Khi hai tia s\u00e1ng n\u00e0y chi\u1ebfu l\u00ean t\u01b0\u1eddng, Youngnh\u1eadn th\u1ea5y c\u00f3 c\u00e1c \u0111i\u1ec3m s\u00e1ng v\u00e0 \u0111i\u1ec3m t\u1ed1i \u0111an xen v\u1edbi nhau. \u0110\u00e2y r\u00f5 r\u00e0ng l\u00e0 hi\u1ec7n t\u01b0\u1ee3ng giao thoa c\u1ee7a \u00e1nh s\u00e1ng (\u0111i\u1ec3m s\u00e1ng l\u00e0 n\u01a1i hai \u0111\u1ec9nh s\u00f3ng giao nhau, c\u00f2n \u0111i\u1ec3m t\u1ed1i l\u00e0 n\u01a1i m\u1ed9t \u0111\u1ec9nh s\u00f3ng giao thoa v\u1edbi m\u1ed9t l\u0169ng s\u00f3ng \u0111\u1ec3 tri\u1ec7t ti\u00eau nhau). Nh\u01b0 v\u1eady, \u00e1nh s\u00e1ng ph\u1ea3i c\u00f3 t\u00ednh s\u00f3ng. Thu\u1ed1c n\u1ed5 \u0111\u01b0\u1ee3c ph\u00e1t minh nh\u01b0 th\u1ebf n\u00e0o? Thu\u1ed1c n\u1ed5 \u0111en l\u00e0 lo\u1ea1i thu\u1ed1c n\u1ed5 m\u00e0 con ng\u01b0\u1eddi s\u1eed d\u1ee5ng s\u1edbm nh\u1ea5t, n\u00f3 \u0111\u01b0\u1ee3c ng\u01b0\u1eddi Trung Qu\u1ed1c ph\u00e1t minh t\u1eeb h\u01a1n 1000 n\u0103m tr\u01b0\u1edbc. T\u00ean c\u1ee7a thu\u1ed1c n\u1ed5 \u0111en c\u00f3 t\u1eeb \u0111\u00e2u ? N\u1ebfu c\u0103n c\u1ee9 v\u00e0o t\u00ean \u0111\u1ec3 suy ngh\u0129 th\u00ec thu\u1ed1c n\u1ed5 \u0111en c\u00f3 l\u1ebd l\u00e0 m\u1ed9t lo\u1ea1i nguy\u00ean li\u1ec7u thu\u1ed1c m\u00e0u \u0111en c\u00f3 th\u1ec3 n\u1ed5 ph\u00e1t ra l\u1eeda. Nh\u01b0ng, thu\u1ed1c n\u1ed5 sao l\u1ea1i li\u00ean quan \u0111\u1ebfn nguy\u00ean li\u1ec7u thu\u1ed1c. \u0110i\u1ec1u n\u00e0y ph\u1ea3i b\u1eaft \u0111\u1ea9u t\u1eeb nh\u1eefng nh\u1eadn th\u1ee9c ban \u0111\u1ea9u c\u1ee7a con ng\u01b0\u1eddi \u0111\u1ed1i v\u1edbi thu\u1ed1c n\u1ed5. Trong th\u1eddi k\u1ef3 c\u1ed5 \u0111\u1ea1i, ngay t\u1eeb r\u1ea5t s\u1edbm con ng\u01b0\u1eddi \u0111\u00e3 l\u1ea5y qu\u1eb7ng nitratkali (di\u00eam ti\u00eau) v\u00e0 l\u01b0u hu\u1ef3nh \u0111\u1ec3 l\u00e0m nh\u1eefng nguy\u00ean li\u1ec7u thu\u1ed1c quan tr\u1ecdng r\u1ed3i. V\u00ed d\u1ee5 nh\u01b0 trong \u201cTh\u1ea9n n\u00f4ng b\u1ea3n th\u1ea3o kinh\u201d th\u1eddi H\u00e1n qu\u1eb7ng nitoratkali \u0111\u01b0\u1ee3c li\u1ec7t v\u00e0o v\u1ecb tr\u00ed s\u1ed1 s\u00e1u trong c\u00e1c lo\u1ea1i thu\u1ed1c th\u01b0\u01a1ng ph\u1ea9m, nghe n\u00f3i n\u00f3 c\u00f3 th\u1ec3 ch\u1eefa \u0111\u01b0\u1ee3c h\u01a1n 20 lo\u1ea1i b\u1ec7nh, l\u01b0u hu\u1ef3nh \u0111\u01b0\u1ee3c li\u1ec7t v\u00e0o v\u1ecb tr\u00ed s\u1ed1 3 trong s\u1ed1 c\u00e1c lo\u1ea1i thu\u1ed1c trung ph\u1ea9m, c\u0169ng c\u00f3 th\u1ec3 tr\u1ecb \u0111\u01b0\u1ee3c h\u01a1n 10 lo\u1ea1i b\u1ec7nh. Hai lo\u1ea1i nguy\u00ean li\u1ec7u thu\u1ed1c n\u00e0y ch\u00ednh l\u00e0 nh\u1eefng lo\u1ea1i nguy\u00ean li\u1ec7u ch\u00ednh \u0111\u1ec3 ch\u1ebf t\u1ea1o thu\u1ed1c n\u1ed5 \u0111en. Theo kh\u1ea3o ch\u1ee9ng th\u00ec lo\u1ea1i thu\u1ed1c n\u1ed5 s\u1edbm nh\u1ea5t \u0111\u01b0\u1ee3c ra \u0111\u1eddi t\u1eeb tay m\u1ed9t nh\u00e0 luy\u1ec7n \u0111\u01a1n. \u1ede th\u1eddi c\u1ed5 \u0111\u1ea1i , \u0111\u1ec3 tho\u1ea3 m\u00e3n ham mu\u1ed1n tr\u01b0\u1eddng th\u1ecd b\u1ea5t l\u00e3o c\u1ee7a m\u00ecnh, c\u00e1c b\u1eadc \u0111\u1ebf v\u01b0\u01a1ng phong ki\u1ebfn \u0111\u00e3 ch\u1ec9 \u0111\u1ecbnh m\u1ed9t nh\u00f3m thu\u1eadt s\u0129 \u0111\u1ed1t l\u00f2 \u0111\u1ec3 nghi\u00ean","c\u1ee9u v\u00e0 \u0111i\u1ec1u ch\u1ebf \u0111\u01a1n d\u01b0\u1ee3c. C\u00e1c thu\u1eadt s\u0129 luy\u1ec7n \u0111\u01a1n \u0111\u00e3 ti\u1ebfn h\u00e0nh c\u00e1c th\u00ed nghi\u1ec7m nh\u01b0 ph\u00e2n li, ho\u00e0 tan, ch\u01b0ng c\u1ea5t, th\u0103ng hoa, \u0111\u1ed1t. nhi\u1ec1u lo\u1ea1i v\u1eadt ch\u1ea5t. \u0110\u00e2y c\u00f3 l\u1ebd l\u00e0 h\u00ecnh th\u1ee9c th\u00ed nghi\u1ec7m ho\u00e1 h\u1ecdc s\u1edbm nh\u1ea5t m\u00e0 con ng\u01b0\u1eddi \u0111\u00e3 l\u00e0m. Thu\u1eadt luy\u1ec7n \u0111\u01a1n tuy b\u1eaft ngu\u1ed3n t\u1eeb m\u01a1 \u01b0\u1edbc c\u1ee7a c\u00e1c b\u1eadc \u0111\u1ebf v\u01b0\u01a1ng nh\u01b0ng ho\u1ea1t \u0111\u1ed9ng th\u1ef1c ti\u1ebfn c\u1ee7a n\u00f3 l\u1ea1i c\u00f3 t\u00e1c d\u1ee5ng th\u00fac \u0111\u1ea9y \u0111\u1ed1i v\u1edbi s\u1ef1 ph\u00e1t tri\u1ec3n c\u1ee7a khoa h\u1ecdc. M\u1ed9t s\u1ed1 t\u00e1c ph\u1ea9m n\u1ed5i ti\u1ebfng c\u1ee7a c\u00e1c nh\u00e0 luy\u1ec7n \u0111\u01a1n \u0111\u1ef1oc l\u01b0u truy\u1ec1n h\u1eadu th\u1ebf \u0111\u00e3 th\u1ec3 hi\u1ec7n nh\u1eefng nh\u1eadn th\u1ee9c t\u1ea1o n\u00ean v\u1eadt ch\u1ea5t c\u1ee7a ng\u01b0\u1eddi x\u01b0a. Thu\u1ed1c n\u1ed5 \u0111en ch\u00ednh l\u00e0 m\u1ed9t trong nh\u1eefng v\u00ed d\u1ee5 \u0111i\u1ec3n h\u00ecnh. Nh\u1eefng nh\u00e0 luy\u1ec7n \u0111\u01a1n Trung Qu\u1ed1c \u0111\u00e3 ti\u1ebfp x\u00fac v\u1edbi c\u00e1c v\u1eadt ch\u1ea5t nh\u01b0 qu\u1eb7ng nit\u01a1ratkali, l\u01b0u hu\u1ef3nh v\u00e0 than g\u1ed7 t\u1eeb r\u1ea5t s\u1edbm v\u00e0 nh\u1eadn th\u1ee9c \u0111\u01b0\u1ee3c r\u1eb1ng khi ch\u00fang tr\u1ed9n l\u1eabn c\u1ecd x\u00e1t ho\u1eb7c va \u0111\u1eadp v\u1edbi nhau th\u00ec th\u01b0\u1eddng s\u1ebd x\u1ea3y ra ch\u00e1y c\u00f3 t\u00ednh n\u1ed5. Nh\u00e0 luy\u1ec7n \u0111\u01a1n th\u1eddi H\u00e1n l\u00e0 Ng\u1ee5y B\u00e1 D\u01b0\u01a1ng \u0111\u00e3 d\u00f9ng l\u01b0u hu\u1ef3nh \u0111\u1ec3 ki\u1ec3m nghi\u1ec7m qu\u1eb7ng nit\u01a1ratkali l\u00e0 th\u1eadt hay gi\u1ea3. Qua c\u1ecd x\u00e1t m\u1ea1nh, n\u1ebfu \u0111\u00fang l\u00e0 qu\u1eb7ng nit\u01a1ratkali th\u00ec g\u1eb7p l\u01b0u hu\u1ef3nh n\u00f3 s\u1ebd ch\u00e1y r\u1ea5t nhanh. Nh\u00e0 luy\u1ec7n \u0111\u01a1n th\u1eddi Nam B\u1eafc tri\u1ec1u \u0110\u00e0o Ho\u1eb1ng C\u1ea3nh c\u0169ng ch\u1ec9 ra ch\u00ednh x\u00e1c r\u1eb1ng, qu\u1eb7ng nit\u01a1ratkali g\u1eb7p than g\u1ed7 \u0111\u1ecf v\u00e0 n\u00f3ng s\u1ebd x\u1ea3y ra ch\u00e1y mang t\u00ednh n\u1ed5. Trong nh\u1eefng n\u0103m \u0111\u1ea9u c\u1ee7a tri\u1ec1u \u0110\u01b0\u1eddng trong cu\u1ed1n s\u00e1ch \u201c\u0110an kinh\u201d nh\u00e0 luy\u1ec7n \u0111\u01a1n T\u00f4n T\u01b0 M\u1ea1o \u0111\u00e3 vi\u1ebft v\u1ec1 c\u00e1ch l\u1ea5y ba th\u1ee9 l\u00e0 qu\u1eb7ng nitoratkali, l\u01b0u hu\u1ef3nh v\u00e0 b\u1ed9t than tr\u1ed9n theo t\u1ef7 l\u1ec7 nh\u1ea5t \u0111\u1ecbnh th\u00e0nh thu\u1ed1c n\u1ed5 \u0111en.T\u1eeb \u0111\u00f3 c\u00f3 th\u1ec3 th\u1ea5y r\u1eb1ng, l\u00fac \u0111\u00f3 m\u1ecdi ng\u01b0\u1eddi \u0111\u00e3 n\u1eafm \u0111\u01b0\u1ee3c \u0111\u1ea9y \u0111\u1ee7 v\u1ec1 c\u00e1ch ch\u1ebf t\u1ea1o v\u00e0 t\u00ednh ch\u1ea5t c\u1ee7a thu\u1ed1c n\u1ed5 \u0111en. Trong nh\u1eefng n\u0103m cu\u1ed1i tri\u1ec1u \u0110\u01b0\u1eddng thu\u1ed1c n\u1ed5 \u0111en b\u1eaft \u0111\u1ea9u \u0111\u01b0\u1ee3c d\u00f9ng v\u00e0o l\u0129nh v\u1ef1c qu\u00e2n s\u1ef1, th\u00e0nh ph\u1ea9n v\u00e0 t\u1ef7 l\u1ec7 thu\u1ed1c n\u1ed5 c\u0169ng ch\u00ednh x\u00e1c h\u01a1n, qu\u1eb7ng nitoratkali 75%, b\u1ed9t than 15%, l\u01b0u hu\u1ef3nh 10%. \u0110\u1ebfn tri\u1ec1u T\u1ed1ng, quy m\u00f4 s\u1ea3n xu\u1ea5t thu\u1ed1c n\u1ed5 li\u00ean t\u1ee5c \u0111\u01b0\u1ee3c m\u1edf r\u1ed9ng, \u0111\u1ea5t n\u01b0\u1edbc c\u00f2n th\u00e0nh l\u1eadp c\u00e1c \u201cc\u00f4ng th\u00e0nh t\u00e1c\u201d (x\u01b0\u1edfng c\u00f4ng binh) trong \u0111\u00f3 c\u00f3 x\u01b0\u1edfng chuy\u00ean s\u1ea3n xu\u1ea5t thu\u1ed1c n\u1ed5 \u0111en l\u00f2 luy\u1ec7n thu\u1ed1c n\u1ed5, quy m\u00f4 t\u1eeb m\u1ea5y t\u1ea5n \u0111\u1ebfn m\u1ea5y ch\u1ee5c t\u1ea5n m\u1ed9t ng\u00e0y. N\u0103m th\u1ee9 t\u01b0 \u0111\u1eddi B\u1eafc T\u1ed1ng (N\u0103m 1040 C\u00f4ng nguy\u00ean) trong \u201cv\u00f5 kinh t\u1ed5ng y\u1ebfu\u201d do T\u0103ng C\u00f4ng L\u01b0\u1ee3ng bi\u00ean so\u1ea1n \u0111\u00e3 vi\u1ebft v\u1ec1 c\u00e1i t\u00ean \u201cthu\u1ed1c n\u1ed5\u201d v\u00e0 t\u1ef7 l\u1ec7 \u0111i\u1ec1u ch\u1ebf c\u00f3 li\u00ean quan. Trong t\u1ef7 l\u1ec7 \u0111i\u1ec1u ch\u1ebf, ngo\u00e0i qu\u1eb7ng nitoratkali, l\u01b0u hu\u1ef3nh , than ra c\u00f2n c\u00f3 th\u00eam c\u00e1c v\u1eadt d\u1ec5 ch\u00e1y nh\u01b0 axit sunfuric, nh\u1ef1a th\u00f4ng, s\u00e1p ong, s\u01a1n kh\u00f4... Kho\u1ea3ng \u0111\u1ea9u th\u1eddi k\u1ef3 Nam T\u1ed1ng, vi\u1ec7c ch\u1ebf t\u1ea1o thu\u1ed1c n\u1ed5 \u0111en \u0111\u01b0\u1ee3c \u0111\u01b0a v\u00e0o trong d\u00e2n gian . Khi \u0103n T\u1ebft ng\u01b0\u1eddi d\u00e2n \u0111\u00e3 d\u00f9ng thu\u1ed1c n\u1ed5 \u0111en \u0111\u1ec3 ch\u1ebf t\u1ea1o ph\u00e1o v\u00e0 ph\u00e1o hoa \u0111\u1ec3 \u0111\u1ed1t. Phong t\u1ee5c n\u00e0y c\u00f2n \u0111\u01b0\u1ee3c gi\u1eef cho \u0111\u1ebfn ng\u00e0y nay. Thu\u1ed1c n\u1ed5 \u0111en l\u00e0 m\u1ed9t lo\u1ea1i ch\u1ea5t h\u1ed7n h\u1ee3p: Qu\u1eb7ng nit\u01a1ratkali l\u00e0 ch\u1ea5t oxy ho\u00e1 sinh ra oxy k\u00edch th\u00edch ch\u00e1y, l\u01b0u hu\u1ef3nh v\u00e0 than l\u00e0 nh\u1eefng ch\u1ea5t c\u00f3 th\u1ec3 ch\u00e1y, khi ch\u00e1y k\u1ebft h\u1ee3p v\u1edbi oxy ho\u00e1 sinh ra c\u00e1c th\u1ec3 kh\u00ed nh\u01b0 S02 , CO2. Nhi\u1ec7t \u0111\u1ed9 b\u1ed1c ch\u00e1y c\u1ee7a l\u01b0u hu\u1ef3nh th\u1ea5p h\u01a1n than l\u00e0m cho thu\u1ed1c n\u1ed5 d\u1ec5 ch\u00e1y h\u01a1n, \u0111\u1ed3ng th\u1eddi l\u01b0u hu\u1ef3nh c\u00f2n ki\u00eam lu\u00f4n vai tr\u00f2 l\u00e0m ch\u1ea5t k\u1ebft d\u00ednh n\u1eefa. Thu\u1ed1c n\u1ed5 \u0111en khi ch\u00e1y c\u00f3 th\u1ec3 sinh ra m\u1ed9t l\u01b0\u1ee3ng l\u1edbn nhi\u1ec7t v\u00e0 kh\u00ed l\u1edbn, l\u00e0m cho kh\u00f4ng kh\u00ed xung quanh d\u00e3n n\u1edf nhanh m\u1ea1nh, \u0111\u1ed9t ng\u1ed9t t\u1ea1o ra hi\u1ec7n t\u01b0\u1ee3ng n\u1ed5.","Thu\u1ed1c n\u1ed5 l\u00e0 m\u1ed9t trong nh\u1eefng ph\u00e1t minh l\u1edbn c\u1ee7a Trung Qu\u1ed1c, sau \u0111\u00f3 truy\u1ec1n t\u1eeb Trung Qu\u1ed1c qua \u1ea4N\u0110\u1ed9, r\u1ed3i x\u00e2m nh\u1eadp v\u00e0o v\u00f9ng \u1ea2 R\u1eadp, r\u1ed3i l\u1ea1i t\u1eeb Ar\u1eadp qua c\u00e1c n\u01b0\u1edbc nh\u01b0 T\u00e2y Ban Nha \u0111\u1ec3 x\u00e2m nh\u1eadp v\u00e0o Ch\u00e2u \u00c2u. Do \u0111\u00f3 Ch\u00e2u \u00c2u xu\u1ea5t hi\u1ec7n thu\u1ed1c n\u1ed5 ch\u1eadm h\u01a1n Trung Qu\u1ed1c v\u00e0i tr\u0103m n\u0103m. Vi\u1ec7c ph\u00e1t minh ra thu\u1ed1c n\u1ed5 kh\u00f4ng nh\u1eefng ch\u1ea5m d\u1ee9t th\u1eddi k\u1ef3 chi\u1ebfn tranh l\u1ea1nh v\u1ec1 m\u1eb7t qu\u00e2n s\u1ef1 m\u00e0 c\u00f2n ph\u00e1t huy \u0111\u01b0\u1ee3c uy l\u1ef1c to l\u1edbn trong vi\u1ec7c x\u00e2y d\u1ef1ng c\u00e1c c\u00f4ng tr\u00ecnh v\u00e0 trong s\u1ea3n xu\u1ea5t c\u00f4ng nghi\u1ec7p. Do \u0111\u00f3, thu\u1ed1c n\u1ed5 \u0111en \u0111\u1ef1\u01a1c coi l\u00e0 m\u1ed1c quan tr\u1ecdng trong l\u1ecbch s\u1eed ho\u00e1 h\u1ecdc . L\u00e0m th\u1ebf n\u00e0o \u0111\u1ec3 x\u00e1c \u0111\u1ecbnh \u0111\u01b0\u1ee3c ni\u00ean \u0111\u1ea1i c\u1ee7a \u0111\u1ed3 g\u1ed1m \u0111\u00e3 \u0111\u01b0\u1ee3c khai qu\u1eadt? \u25a0 \u25a0 \u25a0 o \u25a0 M. m \u1ede c\u00e1c n\u01a1i khai qu\u1eadt \u0111\u01b0\u1ee3c \u0111\u1ed3 g\u1ed1m th\u01b0\u1eddng c\u00f3 m\u1ed9t \u00edt m\u1ea3nh g\u1ed7 b\u1ecb than h\u00f3a ho\u1eb7c m\u1ed9t \u00edt tro than g\u1ed7. Ngo\u00e0i ra trong c\u00e1c ng\u00f4i m\u1ed9 x\u00e2y b\u1eb1ng v\u1ecf s\u00f2 th\u01b0\u1eddng c\u00f3 v\u1ecf s\u00f2, khi khai qu\u1eadt \u0111\u1ed3 g\u1ed1m \u0111\u1ed3ng th\u1eddi c\u0169ng khai qu\u1eadt \u0111\u01b0\u1ee3c m\u1ed9t s\u1ed1 x\u01b0\u01a1ng \u0111\u1ed9ng v\u1eadt. C\u00e1c nh\u00e0 kh\u1ea3o c\u1ed5 c\u00f3 kinh nghi\u1ec7m kh\u00f4ng ch\u1ec9 \u0111o v\u00e0 ph\u00e1t hi\u1ec7n l\u01b0\u1ee3ng cacbon trong tro v\u00e0 c\u00e1c m\u1ea3nh g\u1ed7 c\u00f3 trong ph\u1ea9n m\u1ed9 m\u00e0 c\u00f2n \u0111o h\u00e0m l\u01b0\u1ee3ng c\u00e1c bon \u1edf d\u1ea1ng h\u1ee3p ch\u1ea5t canxi c\u00e1cbon trong x\u01b0\u01a1ng \u0111\u1ed9ng v\u1eadt v\u00e0 v\u1ecf s\u00f2. Trong h\u00e0m l\u01b0\u1ee3ng c\u00e1cbon c\u00f3 c\u00e1c nguy\u00ean t\u1eed c\u00e1c bon c\u00f3 nguy\u00ean t\u1eed l\u01b0\u1ee3ng kh\u00e1c nhau (c\u00e1c \u0111\u1ed3ng v\u1ecb c\u00e1c bon 12, 13, 14). Nguy\u00ean t\u1eed cacbon c\u00f3 kh\u1ed1i l\u01b0\u1ee3ng nguy\u00ean t\u1eed b\u1eb1ng 14 \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 \u0111\u1ed3ng v\u1ecb ph\u00f3ng x\u1ea1 C14 . C\u00e1c bon ph\u00f3ng x\u1ea1 tr\u1ea3i qua th\u1eddi gian s\u1ebd d\u1ea9n d\u1ea9n bi\u1ebfn th\u00e0nh nguy\u00ean t\u1eed nit\u01a1. Th\u1eddi gian \u0111\u1ec3 l\u01b0\u1ee3ng nguy\u00ean t\u1eed c\u00e1c bon C14 c\u00f2n m\u1ed9t n\u1eeda l\u01b0\u1ee3ng ban \u0111\u1ea9u l\u00e0 5730+40 n\u0103m (c\u00f2n g\u1ecdi l\u00e0 chu k\u1ef3 b\u00e1n r\u00e3 hay chu k\u1ef3 t\u00e1n hu\u1ef7). Do v\u1eady ch\u1ec9 c\u1ea9n \u0111o t\u00ednh ph\u00f3ng x\u1ea1 c\u1ee7a C14 c\u00f3 trong g\u1ed7, trong v\u1ecf s\u00f2 khai qu\u1eadt \u0111\u01b0\u1ee3c, ng\u01b0\u1eddi ta c\u00f3 th\u1ec3 bi\u1ebft \u0111\u01b0\u1ee3c ni\u00ean \u0111\u1ea1i c\u1ee5 th\u1ec3 c\u1ee7a ch\u00fang. V\u00ed d\u1ee5 \u1edf Nh\u1eadt B\u1ea3n , \u0111\u1ed3 g\u1ed1m \u0111\u00e0o \u0111\u01b0\u1ee3c \u1edf huy\u1ec7n Catagawa c\u00f3 ni\u00ean \u0111\u1ea1i s\u1edbm nh\u1ea5t 9450+40 n\u0103m v\u1ec1 tr\u01b0\u1edbc, tr\u01b0\u1edbc \u0111\u00e2y, ng\u01b0\u1eddi ta cho r\u1eb1ng d\u01b0 ch\u1ec9 \u1edf huy\u1ec7n Shiba c\u00f3 ni\u00ean \u0111\u1ea1i 5100+40 n\u0103m nh\u01b0ng t\u00ednh theo ph\u01b0\u01a1ng ph\u00e1p \u0111o cacbon ph\u00f3ng xa ni\u00ean \u0111\u1ea1i c\u1ee7a d\u01b0 ch\u1ec9 n\u00e0y l\u00e0 kho\u1ea3ng 1950 n\u0103m. S\u1ee9c m\u1ea1nh k\u1ef3 l\u1ea1 trong qu\u1ea3 c\u1ea7u Magdeburg Ng\u00e0y 8\/5\/1654, ng\u01b0\u1eddi d\u00e2n th\u00e0nh ph\u1ed1 Regensburg, nh\u00e0 vua v\u00e0 c\u00e1c qu\u00fd t\u1ed9c \u0110\u1ee9c, \u0111\u00e3 \u0111\u01b0\u1ee3c m\u1ee5c k\u00edch m\u1ed9t s\u1ef1 vi\u1ec7c k\u1ef3 l\u1ea1: 16 con ng\u1ef1a, chia l\u00e0m hai nh\u00f3m, ra s\u1ee9c k\u00e9o b\u1eadt hai b\u00e1n c\u1ea9u b\u1eb1ng \u0111\u1ed3ng g\u1eafn ch\u1eb7t v\u1edbi nhau v\u1ec1 hai ph\u00eda. Nh\u01b0ng, hai b\u00e1n c\u1ea9u v\u1eabn tr\u01a1 ra! B\u1eb1ng th\u00ed nghi\u1ec7m n\u00e0y, th\u1ecb tr\u01b0\u1edfng th\u00e0nh ph\u1ed1, \u00f4ng Otto von Guericke, \u0111\u00e3 ch\u1ee9ng minh r\u1eb1ng kh\u00f4ng kh\u00ed ho\u00e0n to\u00e0n kh\u00f4ng ph\u1ea3i l\u00e0 \u201ckh\u00f4ng c\u00f3 g\u00ec c\u1ea3\u201d nh\u01b0 m\u1ecdi ng\u01b0\u1eddi v\u1eabn ngh\u0129, r\u1eb1ng n\u00f3 c\u00f3 tr\u1ecdng l\u01b0\u1ee3ng v\u00e0 n\u00e9n v\u1edbi m\u1ed9t l\u1ef1c r\u1ea5t l\u1edbn tr\u00ean t\u1ea5t c\u1ea3 m\u1ecdi v\u1eadt tr\u00ean Tr\u00e1i \u0111\u1ea5t. V\u00e0","\u0111\u00e2y l\u00e0 m\u1ed9t tr\u00edch d\u1ecbch m\u1ed9t \u0111o\u1ea1n v\u1ec1 th\u00ed nghi\u1ec7m n\u00e0y c\u1ee7a Guericke:\u201cTh\u00ed nghi\u1ec7m ch\u1ee9ng minh r\u1eb1ng \u00e1p su\u1ea5t c\u1ee7a kh\u00f4ng kh\u00ed g\u1eafn hai b\u00e1n c\u1ea9u v\u00e0o v\u1edbi nhau ch\u1eafc \u0111\u1ebfn n\u1ed7i 16 con ng\u1ef1a c\u0169ng kh\u00f4ng t\u00e1ch n\u1ed5i ch\u00fang ta\u201d. \u201cT\u00f4i \u0111\u1eb7t l\u00e0m hai b\u00e1n c\u1ea9u b\u1eb1ng \u0111\u1ed3ng \u0111\u01b0\u1eddng k\u00ednh l\u00e0 ba ph\u1ea9n t\u01b0 kh\u1eedu Magdeburg(kho\u1ea3ng 40 cm). Nh\u01b0ng th\u1ef1c t\u1ebf \u0111\u01b0\u1eddng k\u00ednh ch\u1ec9 b\u1eb1ng kho\u1ea3ng 37 cm, b\u1edfi v\u00ec ng\u01b0\u1eddi th\u1ee3 th\u01b0\u1eddng kh\u00f4ng th\u1ec3 l\u00e0m th\u1eadt \u0111\u00fang nh\u01b0 y\u00eau c\u00e2u. Hai b\u00e1n c\u1ea9u ho\u00e0n to\u00e0n \u0103n kh\u00edt v\u1edbi nhau. \u1ede m\u1ed9t b\u00e1n c\u1ea9u c\u00f3 l\u1eafp m\u1ed9t v\u00f2i h\u01a1i, qua v\u00f2i n\u00e0y ng\u01b0\u1eddi ta c\u00f3 th\u1ec3 h\u00fat h\u1ebft kh\u00f4ng kh\u00ed \u1edf trong ra, v\u00e0 kh\u00f4ng cho kh\u00f4ng kh\u00ed \u1edf ngo\u00e0i l\u1ecdt v\u00e0o. Ngo\u00e0i ra tr\u00ean hai b\u00e1n c\u1ea9u c\u00f2n c\u00f3 4 c\u00e1i v\u00f2ng, d\u00f9ng l\u00e0m ch\u1ed7 lu\u1ed3n th\u1eebng bu\u1ed9c n\u1ed1i v\u1edbi y\u00ean ng\u1ef1a. T\u00f4i l\u1ea1i sai hai ng\u01b0\u1eddi kh\u00e2u m\u1ed9t c\u00e1i v\u00f2ng da; r\u1ed3i \u0111em ng\u00e2m v\u00f2ng da v\u00e0o trong h\u1ed7n h\u1ee3p s\u00e1p v\u1edbi d\u1ea9u th\u00f4ng. Sau khi \u0111\u00e3 k\u1eb9p v\u00f2ng da n\u00e0y v\u00e0o gi\u1eefa hai b\u00e1n c\u1ea9u th\u00ec kh\u00f4ng kh\u00ed kh\u00f4ng th\u1ec3 l\u1ecdt v\u00e0o trong n\u1eefa. N\u1ed1i v\u00f2i h\u01a1i v\u1edbi m\u1ed9t b\u01a1m \u0111\u1ec3 r\u00fat h\u1ebft kh\u00f4ng kh\u00ed trong qu\u1ea3 c\u1ea9u ra. L\u00fac \u1ea5y, ng\u01b0\u1eddi ta \u0111\u00e3 th\u1ea5y, qua v\u00f2ng da, hai b\u00e1n c\u1ea9u \u00e9p ch\u1eb7t v\u00e0o nhau m\u1ea1nh \u0111\u1ebfn m\u1ee9c n\u00e0o. \u00c1p su\u1ea5t c\u1ee7a kh\u00f4ng kh\u00ed b\u00ean ngo\u00e0i si\u1ebft ch\u1eb7t ch\u00fang \u0111\u1ebfn n\u1ed7i, 16 con ng\u1ef1a k\u00e9o c\u1eadt l\u1ef1c c\u0169ng kh\u00f4ng t\u00e1ch n\u1ed5i ch\u00fang ra \u0111\u01b0\u1ee3c, ho\u1eb7c n\u1ebfu \u0111\u01b0\u1ee3c th\u00ec c\u0169ng r\u1ea5t t\u1ed1n s\u1ee9c l\u1ef1c. Khi ng\u1ef1a k\u00e9o \u0111\u01b0\u1ee3c hai b\u00e1n c\u1ea9u ra th\u00ec c\u00f2n th\u1ea5y ch\u00fang ph\u00e1t ra ti\u1ebfng n\u1ed5 nh\u01b0 s\u00fang v\u1eady. Nh\u01b0ng ch\u1ec9 c\u1ea9n v\u1eb7n v\u00f2i h\u01a1i \u0111\u1ec3 cho kh\u00f4ng kh\u00ed t\u1ef1 do \u0111i v\u00e0o l\u00e0 l\u1eadp t\u1ee9c c\u00f3 th\u1ec3 l\u1ea5y tay t\u00e1ch hai b\u00e1n c\u1ea9u \u1ea5y ra \u0111\u01b0\u1ee3c d\u1ec5 d\u00e0ng\u201d. M\u1ed9t v\u00e0i ph\u00e9p t\u00ednh \u0111\u01a1n gi\u1ea3n c\u0169ng c\u00f3 th\u1ec3 l\u00e0m cho ch\u00fang ta hi\u1ec3u r\u00f5, t\u1ea1i sao l\u1ea1i ph\u1ea3i d\u00f9ng m\u1ed9t l\u1ef1c l\u1edbn \u0111\u1ebfn th\u1ebf \u0111\u1ec3 t\u00e1ch hai b\u00e1n c\u1ea9u ra. Kh\u00f4ng kh\u00ed n\u00e9n x\u1ea5p x\u1ec9 10 N tr\u00ean m\u1ed7i centim\u00e9t vu\u00f4ng. Di\u1ec7n t\u00edch c\u1ee7a v\u00f2ng tr\u00f2n c\u00f3 \u0111\u01b0\u1eddng k\u00ednh 37 cml\u00e0 kho\u1ea3ng 1.060 centim\u00e9t vu\u00f4ng (\u1edf \u0111\u00e2y ta t\u00ednh di\u1ec7n t\u00edch c\u1ee7a v\u00f2ng tr\u00f2n ch\u1ee9 kh\u00f4ng ph\u1ea3i b\u1ec1 m\u1eb7t c\u1ee7a b\u00e1n c\u1ea9u, b\u1edfi v\u00ec \u00e1p su\u1ea5t kh\u00ed quy\u1ec3n ch\u1ec9 c\u00f3 \u0111\u1ed9 l\u1edbn nh\u01b0 \u0111\u00e3 n\u00f3i khi t\u00e1c d\u1ee5ng vu\u00f4ng g\u00f3c v\u1edbi m\u1ed9t b\u1ec1 m\u1eb7t, c\u00f2n khi t\u00e1c d\u1ee5ng nh\u1eefng b\u1ec1 m\u1eb7t n\u1eb1m nghi\u00eang th\u00ec \u00e1p su\u1ea5t \u0111\u00f3 nh\u1ecf h\u01a1n. Trong tr\u01b0\u1eddng h\u1ee3p n\u00e0y ta ph\u1ea3i l\u1ea5y h\u00ecnh chi\u1ebfu th\u1eb3ng g\u00f3c c\u1ee7a m\u1eb7t c\u1ea9u l\u00ean m\u1eb7t ph\u1eb3ng, ngh\u0129a l\u00e0 l\u1ea5y di\u1ec7n t\u00edch c\u1ee7a v\u00f2ng tr\u00f2n l\u1edbn). Nh\u01b0 th\u1ebf ngh\u0129a l\u00e0 l\u1ef1c \u00e9p c\u1ee7a kh\u00ed quy\u1ec3n tr\u00ean m\u1ed7i b\u00e1n c\u1ea9u ph\u1ea3i h\u01a1n 10.000 N. V\u1eady m\u1ed7i nh\u00f3m 8 con ng\u1ef1a ph\u1ea3i k\u00e9o v\u1edbi m\u1ed9t l\u1ef1c b\u1eb1ng 10.000 N m\u1edbi th\u1eafng n\u1ed5i \u00e1p su\u1ea5t c\u1ee7a kh\u00f4ng kh\u00ed b\u00ean ngo\u00e0i. Nh\u00ecn qua th\u00ec t\u01b0\u1edfng ch\u1eebng con s\u1ed1 \u0111\u00f3 kh\u00f4ng l\u1ea5y g\u00ec l\u00e0m qu\u00e1 n\u1eb7ng so v\u1edbi t\u00e1m con ng\u1ef1a (m\u1ed7i b\u00ean). Nh\u01b0ng b\u1ea1n ch\u1edb qu\u00ean r\u1eb1ng, khi ph\u1ea3i k\u00e9o m\u1ed9t t\u1ea5n h\u00e0ng h\u00f3a, ng\u1ef1a ph\u1ea3i b\u1ecf ra m\u1ed9t l\u1ef1c r\u1ea5t nh\u1ecf h\u01a1n 10.000 N r\u1ea5t nhi\u1ec1u, t\u1ee9c l\u00e0 n\u00f3 ch\u1ec9 ph\u1ea3i th\u1eafng c\u00e1c l\u1ef1c ma s\u00e1t gi\u1eefa c\u00e1c b\u00e1nh xe v\u1edbi tr\u1ee5c, v\u00e0 gi\u1eefa b\u00e1nh xe v\u1edbi \u0111\u01b0\u1eddng nh\u1ef1a m\u00e0 th\u00f4i. M\u00e0 l\u1ef1c ma s\u00e1t n\u00e0y, tr\u00ean \u0111\u01b0\u1eddng nh\u1ef1a, b\u1eb1ng kho\u1ea3ng 500N (\u1edf \u0111\u00e2y ch\u00fang ta c\u0169ng c\u0169ng b\u1ecf qua hi\u1ec7n t\u01b0\u1ee3ng khi t\u00e1m con ng\u1ef1a c\u00f9ng k\u00e9o m\u1ed9t v\u1eadt n\u1eb7ng th\u00ec ch\u00fang b\u1ecb m\u1ea5t \u0111i 50% l\u1ef1c k\u00e9o). Do \u0111\u00f3 l\u1ef1c k\u00e9o 10.000 N c\u1ee7a ng\u1ef1a c\u00f3 th\u1ec3 k\u00e9o \u0111\u01b0\u1ee3c m\u1ed9t xe 20 t\u1ea5n. V\u00e0","nh\u01b0 v\u1eady, khi k\u00e9o b\u00e1n c\u1ea9u ra, t\u00e1m con ng\u1ef1a \u1ea5y \u0111\u00fang l\u00e0 ph\u1ea3i k\u00e9o m\u1ed9t v\u1eadt t\u01b0\u01a1ng \u0111\u01b0\u01a1ng v\u1edbi m\u1ed9t \u0111\u1ea9u m\u00e1y xe l\u1eeda c\u1ee1 nh\u1ecf kh\u00f4ng \u1edf tr\u00ean \u0111\u01b0\u1eddng ray v\u1eady! Ng\u01b0\u1eddi ta \u0111\u00e3 \u0111o \u0111\u01b0\u1ee3c l\u00e0 m\u1ed9t con tu\u1ea5n m\u00e3 k\u00e9o xe v\u1edbi m\u1ed9t l\u1ef1c c\u1ea3 th\u1ea3y l\u00e0 800N. Cho n\u00ean mu\u1ed1n k\u00e9o l\u1eadt \u0111\u01b0\u1ee3c c\u00e1c b\u00e1n c\u1ea9u Magdeburgra (trong tr\u01b0\u1eddng h\u1ee3p l\u1ef1c k\u00e9o c\u1ee7a c\u00e1c con ng\u1ef1a b\u1eb1ng nhau) th\u00ec m\u1ed7i b\u00ean ph\u1ea3i d\u00f9ng 10.000\/800 = 13 con ng\u1ef1a. Ch\u1eafc h\u1eb3n b\u1ea1n \u0111\u1ecdc s\u1ebd v\u00f4 c\u00f9ng kinh ng\u1ea1c n\u1ebfu bi\u1ebft r\u1eb1ng m\u1ed9t s\u1ed1 kh\u1edbp xu\u01a1ng trong c\u01a1 th\u1ec3 ch\u00fang ta s\u1edf d\u0129 kh\u00f4ng r\u1eddi nhau ra, c\u0169ng l\u00e0 do m\u1ed9t nguy\u00ean nh\u00e2n nh\u01b0 \u1edf c\u00e1c b\u00e1n c\u1ea9u Magdegurg. \u00c1p su\u1ea5t kh\u00ed quy\u1ec3n \u0111\u00e3 si\u1ebft ch\u1eb7t c\u00e1c x\u01b0\u01a1ng l\u1ea1i v\u1edbi nhau, b\u1edfi v\u00ec kho\u1ea3ng tr\u1ed1ng gi\u1eefa c\u00e1c kh\u1edbp x\u01b0\u01a1ng kh\u00f4ng c\u00f3 kh\u00f4ng kh\u00ed. Th\u1ebf n\u00e0o l\u00e0 \u201cB\u0103ng tuy\u1ebft kh\u00f4\u201d? Trong m\u1ed9t tr\u00f2 \u1ea3o thu\u1eadt, nh\u00e0 h\u00f3a h\u1ecdc ph\u1ee7 t\u00fai v\u1ea3i v\u00e0o mi\u1ec7ng m\u1ed9t b\u00ecnh th\u00e9p l\u1edbn v\u00e0 m\u1edf van. T\u1eeb mi\u1ec7ng b\u00ecnh b\u1ed1c ra lu\u1ed3ng tuy\u1ebft m\u00e0u tr\u1eafng, l\u00fac sau c\u1ea3 t\u00fai v\u1ea3i ch\u1ee9a \u0111\u1ea9y lo\u1ea1i tuy\u1ebft n\u00e0y. Nh\u00e0 h\u00f3a h\u1ecdc \u0111\u00eam t\u00fai tuy\u1ebft \u0111\u1ed5 l\u00ean m\u1eb7t \u0111\u1ea5t, ch\u1eb3ng m\u1ea5y ch\u1ed1c tuy\u1ebft tr\u1eafng bi\u1ebfn m\u1ea5t. Tuy\u1ebft \u1ea5y \u0111i \u0111\u00e2u? Ch\u1ea5t ch\u1ee9a trong b\u00ecnh kh\u00f4ng ph\u1ea3i l\u00e0 tuy\u1ebft m\u00e0 l\u00e0 .CO2 l\u1ecfng. Khi ch\u1ee9a CO2 v\u00e0o b\u00ecnh n\u00e9n v\u00e0 t\u0103ng \u00e1p l\u1ef1c, n\u00f3 s\u1ebd ho\u00e1 l\u1ecfng. \u1ede th\u1eddi \u0111i\u1ec3m nh\u00e0 ho\u00e1 h\u1ecdc m\u1edf n\u00fat, \u00e1p su\u1ea5t trong binh gi\u1ea3m nhanh khi\u1ebfn CO2 l\u1ecfng bi\u1ebfn th\u00e0nh kh\u00ed. Trong qu\u00e1 tr\u00ecnh n\u00e0y, CO2 thu nhi\u1ec1u nhi\u1ec7t l\u01b0\u1ee3ng l\u00e0m gi\u1ea3m nhi\u1ec7t \u0111\u1ed9, m\u1ed9t b\u1ed9 ph\u1eadn kh\u00ed CO2 s\u1ebd l\u1ea1nh \u0111\u1ebfn m\u1ee9c ho\u00e1 r\u1eafn, tr\u00f4ng b\u1ec1 ngo\u00e0i gi\u1ed1ng nh\u01b0 tuy\u1ebft, c\u0169ng x\u1ed1p v\u00e0 tr\u1eafng. B\u0103ng v\u00e0 tuy\u1ebft th\u1eadt l\u00e0 do n\u01b0\u1edbc t\u1ea1o th\u00e0nh, v\u00ec v\u1eady ch\u00fang ta c\u00f3 c\u1ea3m gi\u00e1c \u1ea9m. CO2 r\u1eafn kh\u00f4ng ph\u1ea3i l\u00e0 n\u01b0\u1edbc n\u00ean khi s\u1edd ch\u00fang ta c\u00f3 c\u1ea3m gi\u00e1c kh\u00f4, v\u00ec v\u1eady c\u00e1c nh\u00e0 khoa h\u1ecdc g\u1ecdi n\u00f3 l\u00e0 \u201cb\u0103ng kh\u00f4\u201d. Nhi\u1ec7t \u0111\u1ed9 c\u1ee7a b\u0103ng kh\u00f4 l\u00e0 -78 \u0111\u1ed9 C, v\u00ec v\u1eady g\u00e2y cho ta c\u1ea3m gi\u00e1c r\u1ea5t l\u1ea1nh, ch\u00fang ta c\u00f3 th\u1ec3 nh\u1eb9 nh\u00e0ng ti\u1ebfp x\u00fac v\u1edbi n\u00f3. C\u1ea9n ch\u00fa \u00fd \u0111\u1eebng bao gi\u1edd s\u1ee5c tay v\u00e0o b\u0103ng kh\u00f4 v\u00ec \u0111i\u1ec1u \u0111\u00f3 c\u00f3 th\u1ec3 g\u00e2y t\u1ed5n th\u01b0\u01a1ng v\u00ec \u0111\u00f4ng l\u1ea1nh. \u1ede nhi\u1ec7t \u0111\u1ed9 cao h\u01a1n 78 \u0111\u1ed9 C, b\u0103ng kh\u00f4 tr\u1ef1c ti\u1ebfp bi\u1ebfn th\u00e0nh kh\u00ed CO2 kh\u00f4ng ph\u1ea3i qua giai \u0111o\u1ea1n ho\u00e1 l\u1ecfng. Ng\u01b0\u1eddi ta g\u1ecdi \u0111\u00f3 l\u00e0 hi\u1ec7n t\u01b0\u1ee3ng th\u0103ng hoa. \u0110\u00f3 l\u00e0 l\u00ed do t\u1ea1i sao khi \u0111\u1ed5 b\u0103ng kh\u00f4 l\u00ean m\u1eb7t \u0111\u1ea5t, n\u00f3 s\u1ebd ho\u00e0n to\u00e0n bi\u1ebfn m\u1ea5t kh\u00f4ng \u0111\u1ec3 l\u1ea1i d\u1ea5u v\u1ebft g\u00ec. \u1ede nhi\u1ec7t \u0111\u1ed9 th\u01b0\u1eddng, b\u0103ng kh\u00f4 b\u1ecb th\u0103ng hoa kh\u00f4ng ng\u1eebng g\u00e2y n\u00ean s\u1ef1 gi\u1ea3m nhi\u1ec7t \u0111\u1ed9. V\u00ec v\u1eady, c\u00f3 th\u1ec3 d\u00f9ng b\u0103ng kh\u00f4 l\u00e0m t\u00e1c nh\u00e2n l\u00e0m l\u1ea1nh. N\u1ebfu \u0111em b\u0103ng kh\u00f4 ch\u1ed9n v\u1edbi propyxenton s\u1ebd t\u1ea1o ra m\u1ed9t h\u1ed7n h\u1ee3p l\u1ea1nh c\u00f3 th\u1ec3 h\u1ea1 \u0111\u01b0\u1ee3c \u0111\u1ebfn nhi\u1ec7t \u0111\u1ed9 100 \u0111\u1ed9 C. C\u00e1c kho \u0111\u00f4ng l\u1ea1nh ho\u1eb7c xe l\u1ea1nh th\u01b0\u1eddng d\u00f9ng b\u0103ng kh\u00f4 \u0111\u1ec3 b\u1ed5 tr\u1ee3 cho t\u00e1c d\u1ee5ng l\u00e0m l\u1ea1nh. Ng\u01b0\u1eddi ta c\u00f2n d\u00f9ng b\u0103ng kh\u00f4 \u0111\u1ec3 l\u00e0m ch\u1ea5t d\u1eadp l\u1eeda ho\u1eb7c l\u00e0m m\u01b0a nh\u00e2n t\u1ea1o. Tuy nhi\u00ean, trong vi\u1ec7c l\u00e0m m\u01b0a nh\u00e2n t\u1ea1o ng\u00e0y nay, ng\u01b0\u1eddi ta th\u01b0\u1eddng d\u00f9ng b\u1ea1c io \u0111ua \u0111\u1ec3 thay b\u0103ng kh\u00f4. T\u1ea1i sao t\u1ed5 ong \u0111\u1ec1u l\u00e0 h\u00ecnh l\u1ee5c gi\u00e1c \u0111\u1ec1u?","N\u1ebfu quan s\u00e1t k\u1ef9 c\u00e0ng t\u1ed5 ong, b\u1ea1n ch\u1eafc ch\u1eafn s\u1ebd r\u1ea5t kinh ng\u1ea1c khi ph\u00e1t hi\u1ec7n ra r\u1eb1ng, k\u1ebft c\u1ea5u c\u1ee7a t\u1ed5 ong th\u1eadt l\u00e0 m\u1ed9t k\u1ef3 t\u00edch c\u1ee7a t\u1ef1 nhi\u00ean, t\u1ed5 ong l\u00e0 do r\u1ea5t nhi\u1ec1u l\u1ed7 v\u1edbi h\u00ecnh d\u1ea1ng to nh\u1ecf kh\u00f4ng gi\u1ed1ng nhau t\u1ea1o th\u00e0nh, nh\u00ecn qua t\u1eeb b\u00ean tr\u00ean, ch\u00fang l\u00e0 h\u00ecnh l\u1ee5c gi\u00e1c \u0111\u1ec1u, nh\u01b0ng s\u1eafp x\u1ebfp r\u1ea5t c\u00f3 tr\u1eadt t\u1ef1. Nh\u01b0ng n\u1ebfu nh\u00ecn t\u1eeb b\u00ean tr\u00e1i, ch\u00fang l\u1ea1i do r\u1ea5t nhi\u1ec1u h\u00ecnh l\u0103ng tr\u1ee5 l\u1ee5c gi\u00e1c \u0111\u1ec1u gh\u00e9p l\u1ea1i v\u1edbi nhau. M\u00e0 \u0111\u00e1y c\u1ee7a m\u1ed7i h\u00ecnh l\u0103ng tr\u1ee5 l\u1ee5c gi\u00e1c \u0111\u1ec1u l\u1ea1i c\u00e0ng l\u00e0m cho con ng\u01b0\u1eddi ta kinh ng\u1ea1c. N\u00f3 kh\u00f4ng ph\u1eb3ng, c\u0169ng kh\u00f4ng ph\u1ea3i tr\u00f2n. M\u00e0 l\u00e0 nh\u1ecdn, l\u00e0 do ba l\u0103ng tr\u1ee5 \u0111\u00e1y nh\u1ecdn ho\u00e0n to\u00e0n gi\u1ed1ng nhau h\u1ee3p th\u00e0nh. H\u00ecnh l\u1ee5c gi\u00e1c \u0111\u1ec1u k\u1ef3 di\u1ec7u \u1edf t\u1ed5 ong t\u1eeb r\u1ea5t l\u00e2u \u0111\u00e3 thu h\u00fat \u0111\u01b0\u1ee3c s\u1ef1 ch\u00fa \u00fd c\u1ee7a con ng\u01b0\u1eddi, t\u1ea1i sao nh\u1eefng ch\u00fa ong nh\u1ecf b\u00e9 l\u1ea1i l\u00e0m t\u1ed5 m\u00ecnh b\u1eb1ng nh\u1eefng h\u00ecnh l\u1ee5c gi\u00e1c \u0111\u1ec1u nh\u1ec9, m\u00e0 kh\u00f4ng ph\u1ea3i l\u00e0 h\u00ecnh tam gi\u00e1c \u0111\u1ec1u, t\u1ee9 gi\u00e1c \u0111\u1ec1u hay l\u00e0 ng\u0169 gi\u00e1c \u0111\u1ec1u? H\u1ea9u h\u1ebft c\u00e1c v\u1eadt th\u1ec3 c\u00f3 h\u00ecnh \u1ed1ng tr\u00f2n, khi m\u1eb7t tr\u01b0\u1edbc, m\u1eb7t sau, b\u00ean ph\u1ea3i, b\u00ean tr\u00e1i ch\u1ecbu \u00e1p l\u1ef1c, b\u1ec1 m\u1eb7t ch\u1ecbu l\u1ef1c c\u1ee7a n\u00f3 s\u1ebd bi\u1ebfn th\u00e0nh h\u00ecnh l\u1ee5c gi\u00e1c. V\u00ec th\u1ebf nh\u00ecn t\u1eeb g\u00f3c \u0111\u1ed9 l\u1ef1c h\u1ecdc, h\u00ecnh l\u1ee5c gi\u00e1c l\u00e0 \u1ed5n \u0111\u1ecbnh nh\u1ea5t. V\u1eady th\u00ec, nh\u1eefng ch\u00fa ong nh\u1ecf khi l\u00e0m t\u1ed5 c\u00f3 ph\u1ea3i l\u00e0 \u0111\u1ec3 tr\u00e1nh \u00e1p l\u1ef1c t\u1eeb b\u00ean ngo\u00e0i v\u00e0 gi\u1eefa c\u00e1c t\u1ed5 v\u1edbi nhau kh\u00f4ng? \u0110\u01b0\u01a1ng nhi\u00ean l\u00e0 kh\u00f4ng ph\u1ea3i r\u1ed3i, b\u1edfi v\u00ec t\u1ed5 ong ngay t\u1eeb ban \u0111\u1ea9u \u0111\u00e3 l\u00e0 m\u1ed9t kh\u1ed1i g\u1eafn li\u1ec1n v\u1edbi nhau r\u1ed3i. \u0110\u1ea9u th\u1ebf k\u1ef7 th\u1ee9 XVIII, nh\u00e0 khoa h\u1ecdc ng\u01b0\u1eddi Ph\u00e1p Malaerqi \u0111\u00e3 t\u1eebng \u0111o \u0111\u01b0\u1ee3c g\u00f3c c\u1ee7a t\u1ed5 ong, ph\u00e1t hi\u1ec7n ra m\u1ed9t quy lu\u1eadt th\u00fa v\u1ecb, \u0111\u00f3 l\u00e0 m\u1ed7i g\u00f3c c\u1ee7a h\u00ecnh l\u0103ng tr\u1ee5 l\u00e0 109 \u0111\u1ed9 26 ph\u00fat, m\u00e0 g\u00f3c nh\u1ecdn l\u00e0 70 \u0111\u1ed9 32 ph\u00fat. Hi\u1ec7n t\u01b0\u1ee3ng n\u00e0y \u0111\u00e3 g\u1ee3i l\u00ean trong \u0111\u1ea9u nh\u00e0 v\u1eadt l\u00fd h\u1ecdc ng\u01b0\u1eddi Ph\u00e1p Leomiule m\u1ed9t g\u1ee3i \u00fd: h\u00ecnh d\u00e1ng c\u1ed1 \u0111\u1ecbnh v\u00e0 \u0111\u1eb7c bi\u1ec7t n\u00e0y, ph\u1ea3i c\u00f3 t\u1ed1n \u00edt nhi\u00ean li\u1ec7u nh\u1ea5t kh\u00f4ng, m\u00e0 di\u1ec7n t\u00edch s\u1eed d\u1ee5ng l\u1ea1i l\u00e0 l\u1edbn nh\u1ea5t? V\u00ec th\u1ebf, \u00f4ng xin \u00fd ki\u1ebfn nh\u00e0 to\u00e1n h\u1ecdc ng\u01b0\u1eddi Th\u1ee5y S\u0129 Kenige, sau khi nghi\u00ean c\u1ee9u t\u1ef7 m\u1ef7, Kenige \u0111\u00e3 ch\u1ee9ng th\u1ef1c cho ph\u1ecfng \u0111o\u00e1n c\u1ee7a \u00f4ng. Nh\u01b0ng g\u00f3c c\u1ee7a t\u1ed5 ong t\u00ednh ra l\u1ea9n n\u00e0y l\u00e0 109 \u0111\u1ed9 26 ph\u00fat v\u00e0 70 \u0111\u1ed9 34 ph\u00fat sai hai ph\u00e2n so v\u1edbi g\u00f3c m\u00e0 Leomiule t\u00ednh ra. N\u0103m 1734, nh\u00e0 to\u00e1n h\u1ecdc Anh l\u1ea1i ti\u1ebfn h\u00e0nh t\u00ednh to\u00e1n t\u1eeb \u0111\u1ea9u, k\u1ebft qu\u1ea3 ho\u00e0n to\u00e0n ph\u00f9 h\u1ee3p v\u1edbi g\u00f3c c\u1ee7a t\u1ed5 ong. Th\u00ec ra, s\u1ed1 li\u1ec7u m\u00e0 Kenige s\u1eed d\u1ee5ng tr\u00ean bi\u1ec3u b\u1ea3ng \u0111\u1ec1u \u0111\u00e3 b\u1ecb in sai. Qua v\u00e0i th\u1ebf k\u1ef7 nghi\u00ean c\u1ee9u k\u1ebft c\u1ea5u c\u1ee7a t\u1ed5 ong, con ng\u01b0\u1eddi ph\u00e1t hi\u1ec7n ra k\u1ebft c\u1ea5u n\u00e0y c\u00f3 l\u1ee3i nh\u1ea5t cho vi\u1ec7c ti\u1ebft ki\u1ec7m nhi\u00ean li\u1ec7u v\u00e0 t\u1eadn d\u1ee5ng kh\u00f4ng gian. Con ng\u01b0\u1eddi c\u00f2n t\u00ecm ra kh\u00f4ng \u00edt nh\u1eefng v\u1eadn d\u1ee5ng di\u1ec7u k\u1ef3 c\u1ee7a n\u00f3. Hi\u1ec7n nay con ng\u01b0\u1eddi \u0111ang \u1ee9ng d\u1ee5ng r\u1ed9ng r\u00e3i trong c\u00e1c l\u0129nh v\u1ef1c nh\u01b0 ki\u1ebfn tr\u00fac, h\u00e0ng kh\u00f4ng, v\u00f4 tuy\u1ebfn \u0111i\u1ec7n. T\u1eeb ki\u1ebfn tr\u00fac \u201cT\u1ea9ng h\u1ea9m ki\u1ec3u t\u1ed5 ong\u201d c\u00e1ch \u00e2m c\u00e1ch \u0111i\u1ec7u \u0111\u1ebfn thi\u1ebft k\u1ebf con t\u00e0u con thoi ph\u00f3ng v\u00e0o v\u0169 tr\u1ee5, \u0111\u1ec1u quan h\u1ec7 m\u1eadt thi\u1ebft v\u1edbi k\u1ebft c\u1ea5u c\u1ee7a t\u1ed5 ong. V\u00ec sao b\u00f3ng bay b\u01a1m kh\u00ed heli ch\u00f3ng x\u1eb9p?","Hai qu\u1ea3 b\u00f3ng bay gi\u1ed1ng h\u1ec7t nhau, m\u1ed9t b\u01a1m b\u1eb1ng kh\u00f4ng kh\u00ed th\u01b0\u1eddng, m\u1ed9t b\u01a1m b\u1eb1ng kh\u00ed heli. \u0110\u01b0\u1ee3c m\u1ed9t l\u00fac, b\u00f3ng b\u01a1m kh\u00ed heli \u0111\u00e3 teo l\u1ea1i, d\u00fam d\u00f3 d\u1ea9n, trong khi qu\u1ea3 kia h\u1ea9u nh\u01b0 v\u1eabn tr\u00f2n c\u0103ng cho \u0111\u1ebfn v\u00e0i ng\u00e0y sau. B\u00f3ng k\u00edn nh\u01b0 th\u1ebf , heli tho\u00e1t \u0111i \u0111\u00e2u? Heli l\u00e0 lo\u1ea1i kh\u00ed r\u1ea5t nh\u1eb9. C\u00e1c ph\u00e2n t\u1eed c\u1ee7a n\u00f3 \u0111\u01b0\u1ee3c c\u1ea5u t\u1ea1o t\u1eeb c\u00e1c \u0111\u01a1n nguy\u00ean t\u1eed, n\u00ean c\u00f3 k\u00edch th\u01b0\u1edbc r\u1ea5t nh\u1ecf b\u00e9, \u0111\u01b0\u1eddng k\u00ednh ch\u1ec9 b\u1eb1ng 0,1 nanom\u00e9t. Nh\u1edd th\u00e2n h\u00ecnh \u201cc\u1ef1c mini\u201d n\u00e0y, heli r\u1ea5t d\u1ec5 d\u00e0ng khuy\u1ebfch t\u00e1n qua m\u00e0ng kim lo\u1ea1i nh\u1edd \u201cvi h\u00e0nh\u201d theo c\u00e1c khe h\u1ed5ng, l\u1ed7 r\u1ed7ng, do v\u1eady ng\u01b0\u1eddi ta th\u01b0\u1eddng s\u1eed d\u1ee5ng n\u00f3 \u0111\u1ec3 ki\u1ec3m tra ch\u1ea5t l\u01b0\u1ee3ng c\u00e1c h\u1ec7 th\u00f4ng h\u00fat b\u1ee5i trong ph\u00f2ng th\u00ed nghi\u1ec7m v\u00e0 trong c\u00f4ng nghi\u1ec7p, xem ch\u00fang c\u00f3 b\u1ecb c\u00e1c khe n\u1ee9t hay kh\u00f4ng. Khi b\u01a1m heli v\u00e0o b\u00f3ng, kh\u00ed n\u00e0y s\u1ebd nhanh ch\u00f3ng tho\u00e1t ra ngo\u00e0i theo c\u00e1c khe, \u1ed1ng nh\u1ecf x\u00edu tr\u00ean v\u1ecf b\u00f3ng bay, l\u00e0m b\u00f3ng x\u1eb9p \u0111i nhanh ch\u00f3ng. Trong khi \u0111\u00f3, ph\u00e2n t\u1ef7 nit\u01a1 v\u00e0 oxy (hai kh\u00ed ch\u00ednh trong kh\u00ed quy\u1ec3n) c\u00f3 \u0111\u01b0\u1eddng k\u00ednh l\u1edbn h\u01a1n nhi\u1ec1u nguy\u00ean t\u1eed heli, n\u00ean ch\u00fang \u00edt b\u1ecb khuy\u1ebfch t\u00e1n qua v\u1ecf b\u00f3ng bay. M\u1ed9t nguy\u00ean nh\u00e2n kh\u00e1c c\u0169ng khi\u1ebfn h\u01a1i nhanh ch\u00f3ng tho\u00e1t ra l\u00e0 do c\u1ea5u t\u1ea1o c\u1ee7a v\u1ecf b\u00f3n g. B\u00f3ng bay \u0111\u01b0\u1ee3c l\u00e0m t\u1eeb ch\u1ea5t d\u1ebbo, l\u00e0 m\u1ed9t t\u1eadp h\u1ee3p c\u00e1c s\u1ee3i polyme \u0111an v\u00e0o nhau. C\u00e1c s\u1ee3i n\u00e0y kh\u00f4ng th\u1ec3 s\u00edt ch\u1eb7t v\u1edbi nhau, m\u00e0 c\u00f2n \u0111\u1ec3 ch\u1eeba c\u00e1c l\u1ed7 h\u1ed5ng, hay c\u00e1c khe, r\u00e3nh. V\u00ec th\u1ebf, ngay \u1edf \u00e1p su\u1ea5t th\u1ea5p, heli v\u1eabn c\u00f3 th\u1ec3 khuy\u1ebfch t\u00e1n ra ngo\u00e0i nh\u01b0 th\u01b0\u1eddng. Khi b\u00f3ng \u0111\u01b0\u1ee3c b\u01a1m c\u0103ng, c\u00e1c s\u1ee3i polyme gi\u00e3n ra, v\u1ecf b\u00f3ng tr\u1edf n\u00ean m\u1ecfng h\u01a1n, l\u1ed7 r\u1ed7ng m\u1edf r\u1ed9ng ra, \u00e1p l\u1ef1c t\u0103ng l\u00ean \u0111\u1ea9y c\u00e1c ph\u00e2n t\u1eed kh\u00ed chui ra ngo\u00e0i nhanh h\u01a1n, \u0111i qua \u201cqu\u00e3ng \u0111\u01b0\u1eddng\u201d ng\u1eafn h\u01a1n. \u0110\u00f3 l\u00e0 c\u00e1c l\u00fd do t\u1ea1i sao khi b\u00f3ng c\u0103ng, qu\u00e1 tr\u00ecnh x\u1eb9p h\u01a1i di\u1ec5n ra r\u1ea5t nhanh v\u00e0 ch\u1eadm d\u1ea9n khi k\u00edch c\u1ee1 qu\u1ea3 b\u00f3ng b\u00f3ng thu nh\u1ecf l\u1ea1i. B\u00f3ng c\u00f3 th\u1ec3 t\u1ef1 ph\u1ed3ng l\u00ean? Tuy nhi\u00ean, b\u1ea1n c\u0169ng s\u1ebd nh\u1eadn th\u1ea5y qu\u1ea3 b\u00f3ng kh\u00f4ng ho\u00e0n to\u00e0n x\u1ecbt h\u1eb3n. \u0110\u00f3 l\u00e0 do ngo\u00e0i d\u00f2ng kh\u00ed \u0111i ra, c\u00f2n c\u00f3 d\u00f2ng khi \u0111i t\u1eeb b\u00ean ngo\u00e0i \u0111i v\u00e0o c\u0169ng chui qua c\u00e1c khe r\u1ed7ng n\u00e0y. N\u1ebfu qu\u1ea3 b\u00f3ng \u0111\u01b0\u1ee3c b\u01a1m \u0111\u1ea9y khi sulphur hexaflourid(c\u00f3 k\u00edch th\u01b0\u1edbc ph\u00e2n t\u1eed r\u1ea5t l\u1edbn, r\u1ea5t kh\u00f3 khuy\u1ebfch t\u00e1n ra ngo\u00e0i) th\u00ec ch\u00fang s\u1ebd kh\u00f4ng b\u1ecb x\u1eb9p \u0111i. \u0110\u1ed3ng th\u1eddi, kh\u00f4ng kh\u00ed t\u1eeb ngo\u00e0i l\u1ea1i \u0111i v\u00e0o trong qu\u1ea3 b\u00f3ng, khi\u1ebfn n\u00f3 d\u1ea9n d\u1ea9n t\u0103ng l\u00ean v\u1ec1 k\u00edch c\u1ee1. Hi\u1ec7n nay, ng\u01b0\u1eddi \u0111\u00e3 ch\u1ebf t\u1ea1o ra nh\u1eefng lo\u1ea1i b\u00f3ng bay l\u00e0m t\u1eeb v\u1eadt li\u1ec7u kh\u00f4ng \u0111\u00e0n h\u1ed3i, kh\u00f4ng c\u00f3 l\u1ed7 r\u1ed7ng v\u00e0 \u0111\u01b0\u1ee3c ph\u1ee7 m\u00e0ng \u0111\u1ec3 gi\u1ea3m s\u1ef1 tho\u00e1t kh\u00ed. M\u1eb7c d\u00f9 v\u1eabn c\u00f3 hi\u1ec7n t\u01b0\u1ee3ng x\u1eb9p h\u01a1i, nh\u01b0ng ch\u1eafc ch\u1eafn, th\u1eddi gian c\u0103ng tr\u00f2n c\u1ee7a b\u00f3ng \u0111\u1ee7 cho tr\u1ebb em ch\u01a1i \u0111\u1ebfn khi ch\u00fang ch\u00e1n tr\u00f2 n\u00e0y. B\u0103ng tr\u00ean m\u00e1i nh\u00e0 h\u00ecnh th\u00e0nh nh\u01b0 th\u1ebf n\u00e0o?","\u0110\u00e3 bao gi\u1edd b\u1ea1n t\u1ef1 h\u1ecfi, nh\u1eefng c\u1ed9t n\u01b0\u1edbc \u0111\u00e1 bu\u00f4ng th\u00f5ng t\u1eeb m\u00e1i nh\u00e0 xu\u1ed1ng h\u00ecnh th\u00e0nh trong giai \u0111o\u1ea1n b\u0103ng tan hay b\u0103ng gi\u00e1. N\u1ebfu trong ng\u00e0y b\u0103ng tan, th\u00ec ch\u1eb3ng l\u1ebd n\u01b0\u1edbc c\u00f3 th\u1ec3 \u0111\u00f3ng b\u0103ng \u1edf nhi\u1ec7t \u0111\u1ed9 tr\u00ean s\u1ed1 kh\u00f4ng? C\u00f2n n\u1ebfu trong ng\u00e0y b\u0103ng gi\u00e1, th\u00ec l\u1ea5y \u0111\u00e2u ra n\u01b0\u1edbc tr\u00ean m\u00e1i nh\u00e0? V\u1ea5n \u0111\u1ec1 kh\u00f4ng \u0111\u01a1n gi\u1ea3n nh\u01b0 ch\u00fang ta t\u01b0\u1edfng. Mu\u1ed1n h\u00ecnh th\u00e0nh nh\u1eefng c\u1ed9t b\u0103ng th\u00ec trong c\u00f9ng m\u1ed9t l\u00fac ph\u1ea3i c\u00f3 hai nhi\u1ec7t \u0111\u1ed9: nhi\u1ec7t \u0111\u1ed9 \u0111\u1ec3 l\u00e0m tan b\u0103ng tr\u00ean s\u1ed1 kh\u00f4ng , v\u00e0 nhi\u1ec7t \u0111\u1ed9 \u0111\u1ec3 l\u00e0m \u0111\u00f3ng b\u0103ng d\u01b0\u1edbi s\u1ed1 kh\u00f4ng. Trong th\u1ef1c t\u1ebf \u0111\u00fang nh\u01b0 v\u1eady: Tuy\u1ebft tr\u00ean m\u00e1i nh\u00e0 d\u1ed1c tan ra v\u00ec \u00e1nh s\u00e1ng M\u1eb7t tr\u1eddi s\u01b0\u1edfi n\u00f3ng t\u1edbi nhi\u1ec7t \u0111\u1ed9 tr\u00ean s\u1ed1 kh\u00f4ng, nh\u01b0ng khi ch\u1ea3y \u0111\u1ebfn r\u00eca m\u00e1i gianh th\u00ec n\u00f3 \u0110\u00f4ng l\u1ea1i, v\u00ec nhi\u1ec7t \u0111\u1ed9 \u1edf \u0111\u00e2y d\u01b0\u1edbi s\u1ed1 kh\u00f4ng. B\u1ea1n h\u00e3y h\u00ecnh dung m\u1ed9t c\u1ea3nh th\u1ebf n\u00e0y. V\u00e0o m\u1ed9t ng\u00e0y quang m\u00e2y, tr\u1eddi v\u1eabn b\u0103ng gi\u00e1 v\u1eabn l\u00e0 1 -2 \u0111\u1ed9 d\u01b0\u1edbi kh\u00f4ng. M\u1eb7t tr\u1eddi to\u1ea3 \u00e1nh s\u00e1ng, song nh\u1eefng tia n\u1eafng xi\u00ean \u1ea5y kh\u00f4ng s\u01b0\u1edfi \u1ea5m Tr\u00e1i \u0111\u1ea5t \u0111\u1ee7 l\u00e0m cho tuy\u1ebft c\u00f3 th\u1ec3 tan. Nh\u01b0ng tr\u00ean m\u00e1i d\u1ed1c h\u01b0\u1edbng v\u1ec1 ph\u00eda M\u1eb7t tr\u1eddi, tia n\u1eafng chi\u1ebfu xu\u1ed1ng kh\u00f4ng xi\u00ean nh\u01b0 tr\u00ean m\u1eb7t \u0111\u1ea5t, m\u00e0 d\u1ef1ng \u0111\u1ee9ng h\u01a1n, nghi\u00eang m\u1ed9t g\u00f3c g\u1ea9n v\u1edbi g\u00f3c vu\u00f4ng h\u01a1n. M\u00e0 ta bi\u1ebft g\u00f3c h\u1ee3p b\u1edfi tia s\u00e1ng v\u00e0 m\u1eb7t ph\u1eb3ng chi\u1ebfu n\u00f3 chi\u1ebfu t\u1edbi c\u00e0ng l\u1edbn th\u00ec tia s\u00e1ng c\u00e0ng m\u1ea1nh v\u00e0 s\u01b0\u1edfi n\u00f3ng nhi\u1ec1u h\u01a1n (t\u00e1c d\u1ee5ng c\u1ee7a tia s\u00e1ng t\u1ef7 l\u1ec7 v\u1edbi sin c\u1ee7a g\u00f3c \u0111\u00f3, nh\u01b0 tr\u01b0\u1eddng h\u1ee3p h\u00ecnh tr\u00ean, tuy\u1ebft tr\u00ean n\u00f3c nh\u00e0 nh\u1eadn \u0111\u01b0\u1ee3c nhi\u1ec7t nhi\u1ec1u g\u1ea5p 2,5 l\u1ea9n so v\u1edbi tuy\u1ebft tr\u00ean m\u1eb7t \u0111\u1ea5t n\u1eb1m ngang, b\u1edfi v\u00ec sin 60 \u0111\u1ed9 l\u1edbn g\u1ea5p 2,5 l\u1ea9n sin 20 \u0111\u1ed9). \u0110\u00f3 l\u00e0 l\u00fd do t\u1ea1i sao m\u1eb7t d\u1ed1c c\u1ee7a n\u00f3c nh\u00e0 \u0111\u01b0\u1ee3c s\u01b0\u1edfi n\u00f3ng m\u1ea1nh h\u01a1n v\u00e0 tuy\u1ebft tr\u00ean \u0111\u00f3 c\u00f3 th\u1ec3 tan ra. N\u01b0\u1edbc tuy\u1ebft v\u1eeba tan ch\u00e0y th\u00e0nh t\u1eebng gi\u1ecdt, t\u1eebng gi\u1ecdt xu\u1ed1ng r\u00eca m\u00e1i gianh. Nh\u01b0ng \u1edf b\u00ean d\u01b0\u1edbi r\u00eca m\u00e1i gianh, nhi\u1ec7t \u0111\u1ed9 th\u1ea5p h\u01a1n s\u1ed1 kh\u00f4ng v\u00e0 gi\u1ecdt n\u01b0\u1edbc (do c\u00f2n b\u1ecb b\u1ed1c h\u01a1i n\u1eefa) n\u00ean \u0111\u00f3ng b\u0103ng l\u1ea1i. Ti\u1ebfp t\u1ee5c \u0111\u00f3 gi\u1ecdt n\u01b0\u1edbc tuy\u1ebft th\u1ee9 hai ch\u1ea3y \u0111\u1ebfn c\u0169ng \u0110\u00f4ng l\u1ea1i... c\u1ee9 th\u1ebf ti\u1ebfp t\u1ee5c m\u00e3i, d\u1ea9n d\u1ea9n h\u00ecnh th\u00e0nh m\u1ed9t m\u1ecfm b\u1eb3ng nho nh\u1ecf. R\u1ed3i m\u1ed9t l\u1ea9n kh\u00e1c, th\u1eddi ti\u1ebft c\u0169ng t\u01b0\u01a1ng t\u1ef1 nh\u01b0 th\u1ebf, v\u00e0 nh\u1eefng m\u1ecfm b\u0103ng n\u00e0y \u0111\u01b0\u1ee3c d\u00e0i th\u00eam ra, cu\u1ed1i c\u00f9ng tr\u1edf th\u00e0nh nh\u1eefng c\u1ed9t b\u0103ng gi\u1ed1ng nh\u01b0 nh\u1eefng th\u1ea1ch nh\u0169 \u0111\u00e1 v\u00f4i trong c\u00e1c hang \u0111\u1ed9ng v\u1eady. N\u00f3i chung tr\u00ean c\u00e1c c\u0103n nh\u00e0 kh\u00f4ng \u0111\u01b0\u1ee3c s\u01b0\u1edfi \u1ea5m, c\u00e1c c\u1ed9t b\u0103ng c\u0169ng h\u00ecnh th\u00e0nh t\u01b0\u01a1ng t\u1ef1 nh\u01b0 tr\u00ean D\u00f9ng b\u0103ng l\u1ea5y l\u1eeda nh\u01b0 th\u1ebf n\u00e0o ? Gi\u1ea3 s\u1eed b\u1ea1n b\u1ecb l\u1ea1c l\u00ean m\u1ed9t b\u0103ng \u0111\u1ea3o v\u00e0 qu\u00ean mang theo di\u00eam ho\u1eb7c b\u1eadt l\u1eeda. Xung quanh ch\u1ec9 c\u00f3 b\u0103ng tuy\u1ebft v\u00e0 nh\u1eefng c\u00e0nh c\u1ee7i kh\u00f4. L\u00fac \u1ea5y, c\u00f3 th\u1ec3 b\u1ea1n s\u1ebd ph\u1ea3i d\u00f9ng b\u0103ng l\u1ea5y l\u1eeda. Th\u1ebf nh\u01b0ng b\u0103ng l\u00e0 n\u01b0\u1edbc ho\u00e1 \u0111\u1eb7c \u1edf nhi\u1ec7t \u0111\u1ed9 r\u1ea5t th\u1ea5p, l\u00e0m sao c\u00f3 th\u1ec3 sinh l\u1eeda \u0111\u01b0\u1ee3c? \u1ede \u0111\u00e2y b\u1ea1n ph\u1ea3i s\u1eed d\u1ee5ng m\u1ed9t nguy\u00ean l\u00fd trong quang h\u1ecdc, \u0111\u00f3 l\u00e0 k\u00ednh l\u1ed3i \u0111\u1ec3 h\u1ed9i t\u1ee5 \u00e1nh s\u00e1ng. Ng\u01b0\u1eddi ta c\u00f3 th\u1ec3 \u0111\u1eafp b\u0103ng th\u00e0nh nh\u1eefng chi\u1ebfc k\u00ednh l\u1ed3i l\u1edbn, trong su\u1ed1t, r\u1ed3i \u0111\u1eb7t nghi\u00eang h\u1ee9ng \u00e1nh n\u1eafng M\u1eb7t tr\u1eddi. Khi \u00e1nh s\u00e1ng \u0111i qua chi\u1ebfc \u201ck\u00ednh b\u0103ng\u201d n\u00e0y, n\u00f3 s\u1ebd kh\u00f4ng h\u00e2m n\u00f3ng b\u0103ng, m\u00e0 n\u0103ng l\u01b0\u1ee3ng \u0111\u01b0\u1ee3c t\u1ee5 l\u1ea1i th\u00e0nh m\u1ed9t \u0111i\u1ec3m nh\u1ecf.","N\u1ebfu chi\u1ebfc k\u00ednh b\u0103ng r\u1ed9ng 1 m\u00e9t v\u00e0 d\u00e0y kho\u1ea3ng 30 centim\u00e9t, th\u00ec n\u0103ng l\u01b0\u1ee3ng \u00e1nh s\u00e1ng M\u1eb7t tr\u1eddi m\u00e0 n\u00f3 h\u1ed9i t\u1ee5 c\u00f3 th\u1ec3 \u0111\u1ee7 l\u1edbn \u0111\u1ec3 \u0111\u1ed1t ch\u00e1y m\u1ed9t \u0111\u00e1m c\u1ee7i kh\u00f4. Nh\u00e0 v\u0103n vi\u1ec5n t\u01b0\u1edfng Jule Verne \u0111\u00e3 d\u1ef1a tr\u00ean nguy\u00ean l\u00fd n\u00e0y \u0111\u1ec3 vi\u1ebft ra cu\u1ed1n truy\u1ec7n phi\u00eau li\u00eau \u201cCu\u1ed9c du l\u1ecbch c\u1ee7a vi\u00ean thuy\u1ec1n tr\u01b0\u1edfng Hatterat\u201d m\u00e0 trong \u0111\u00f3, c\u00e1c nh\u00e2n v\u1eadt trong truy\u1ec7n \u0111\u00e3 d\u00f9ng th\u1ea5y k\u00ednh b\u0103ng l\u1ea5y l\u1eeda \u1edf nhi\u1ec7t \u0111\u1ed9 48 \u0111\u1ed9 C! T\u1ea1i sao n\u01b0\u1edbc kh\u00f4ng th\u1ec3 ch\u00e1y \u0111\u01b0\u1ee3c? V\u1ea5n \u0111\u1ec1 n\u00e0y xem ra c\u00f3 v\u1ebb h\u01a1i th\u1eeba. N\u01b0\u1edbc kh\u00f4ng th\u1ec3 ch\u00e1y \u0111\u01b0\u1ee3c, \u0111\u00e2y l\u00e0 \u0111i\u1ec1u m\u00e0 ai c\u0169ng bi\u1ebft. Nh\u01b0ng, t\u1ea1i sao n\u01b0\u1edbc l\u1ea1i kh\u00f4ng th\u1ec3 ch\u00e1y \u0111\u01b0\u1ee3c? \u0110\u1ec3 n\u00f3i r\u00f5 v\u1ea5n \u0111\u1ec1 n\u00e0y, tr\u01b0\u1edbc ti\u00ean ch\u00fang ta ph\u1ea3i l\u00e0m r\u00f5, ch\u00e1y l\u00e0 nh\u01b0 th\u1ebf n\u00e0o? Ch\u00e1y th\u01b0\u1eddng l\u00e0 m\u1ed9t qu\u00e1 tr\u00ecnh ch\u1ec9 s\u1ef1 ho\u00e1 h\u1ee3p m\u1ea1ng gi\u1eefa v\u1eadt ch\u1ea5t v\u00e0 kh\u00ed oxy. C\u00f3 m\u1ed9t s\u1ed1 v\u1eadt ch\u1ea5t m\u1eb7c d\u00f9 l\u00e0 \u1edf nhi\u1ec7t \u0111\u1ed9 th\u01b0\u1eddng nh\u01b0ng ch\u1ec9 c\u1ea9n c\u00f3 c\u01a1 h\u1ed9i \u201cg\u1eb7p m\u1eb7t\u201d v\u1edbi kh\u00ed oxy l\u00e0 n\u00f3 l\u1eadp t\u1ee9c \u201ck\u1ebft h\u1ee3p\u201d v\u1edbi oxy v\u00e0 t\u1ef1 \u0111\u1ed9ng ch\u00e1y. Photpho tr\u1eafng ch\u00ednh l\u00e0 nh\u01b0 v\u1eady. Ngo\u00e0i ra, c\u00f3 m\u1ed9t s\u1ed1 ch\u1ea5t nh\u01b0 than (th\u00e0nh ph\u1ea9n ch\u1ee7 y\u1ebfu l\u00e0 cacbon), kh\u00ed hydro, l\u01b0u hu\u1ef3nh. m\u1eb7c d\u00f9 \u1edf nhi\u1ec7t \u0111\u1ed9 th\u01b0\u1eddng khi ti\u1ebfp x\u00fac v\u1edbi oxy 2 b\u00ean kh\u00f4ng h\u1ec1 c\u00f3 ph\u1ea3n \u1ee9ng g\u00ec, nh\u01b0ng khi nhi\u1ec7t \u0111\u1ed9 t\u0103ng, ch\u00fang s\u1ebd ch\u00e1y m\u1ea1nh. Nh\u00ecn b\u00ean ngo\u00e0i th\u00ec h\u00ecnh d\u00e1ng c\u1ee7a c\u1ed3n, x\u0103ng, d\u1ea9u v\u00e0 n\u01b0\u1edbc g\u1ea9n gi\u1ed1ng nhau, \u0111\u1ec1u l\u00e0 th\u1ec3 l\u1ecfng kh\u00f4ng trong su\u1ed1t. Nh\u01b0ng c\u1ed3n l\u00e0 do 3 nguy\u00ean t\u1ed1 Cacbom, Hydro, Oxy t\u1ea1o n\u00ean, c\u00f2n x\u0103ng v\u00e0 d\u1ea9u ch\u1ec9 ch\u1ee9a Cacbon v\u00e0 Hydro. Tr\u00ean th\u1ef1c t\u1ebf, \u0111a s\u1ed1 c\u00e1c h\u1ee3p ch\u1ea5t ho\u00e1 h\u1ecdc ch\u1ee9a Cacbon \u0111\u1ec1u c\u00f3 th\u1ec3 t\u1ef1 ch\u00e1y. C\u1ed3n, x\u0103ng, d\u1ea9u sau khi ch\u00e1y, m\u1ed7i m\u1ed9t nguy\u00ean t\u1eed cacbon k\u1ebft h\u1ee3p v\u1edbi hai nguy\u00ean t\u1eed oxy bi\u1ebfn th\u00e0nh C02, c\u00f2n kh\u00ed hydrok\u1ebft h\u1ee3p v\u1edbi oxi th\u00e0nh n\u01b0\u1edbc, ch\u00fang \u0111\u00e3 ch\u00e1y s\u1ea1ch r\u1ed3i. \u0110\u1ecdc \u0111\u1ebfn \u0111\u1ea5y c\u00f3 l\u1ebd b\u1ea1n \u0111\u00e3 bi\u1ebft r\u1ed3i, n\u01b0\u1edbc t\u1ea1i sao kh\u00f4ng th\u1ec3 ch\u00e1y \u0111\u01b0\u1ee3c. N\u01b0\u1edbc l\u00e0 do hai nguy\u00ean t\u1ed1 hydrov\u00e0 oxy t\u1ea1o n\u00ean. C\u0169ng t\u1ee9c l\u00e0, n\u01b0\u1edbc l\u00e0 s\u1ea3n ph\u1ea9m sau khi kh\u00ed hydro ch\u00e1y. \u0110\u00e3 l\u00e0 s\u1ea3n ph\u1ea9m c\u1ee7a s\u1ef1 ch\u00e1y th\u00ec \u0111\u01b0\u01a1ng nhi\u00ean n\u00f3 kh\u00f4ng c\u00f2n kh\u1ea3 n\u0103ng k\u1ebft h\u1ee3p v\u1edbi kh\u00ed oxy n\u1eefa, c\u0169ng t\u1ee9c l\u00e0 n\u00f3 kh\u00f4ng ch\u00e1y n\u1eefa. C\u0169ng nh\u01b0 v\u1eady, C02 l\u00e0 s\u1ea3n ph\u1ea9m cu\u1ed1i c\u00f9ng c\u1ee7a s\u1ef1 ch\u00e1y, cho n\u00ean n\u00f3 c\u0169ng kh\u00f4ng th\u1ec3 ch\u00e1y n\u1eefa. DoC02 kh\u00f4ng th\u1ec3 k\u00edch th\u00edch ch\u00e1y, h\u01a1n n\u1eefa c\u00f2n n\u1eb7ng h\u01a1n kh\u00f4ng kh\u00ed cho n\u00ean con ng\u01b0\u1eddi c\u00f3 th\u1ec3 xoay ng\u01b0\u1ee3c l\u1ea1i, l\u1ee3i d\u1ee5ng n\u00f3 \u0111\u1ec3 c\u1ee9u ho\u1ea3. Tuy nhi\u00ean, c\u0169ng c\u00f3 kh\u00f4ng \u00edt c\u00e1c v\u1eadt ch\u1ea5t kh\u00f4ng \u201ch\u1ee3p\u201d v\u1edbi kh\u00ed oxy, cho d\u00f9 b\u1ea1n c\u00f3 h\u00e2m n\u00f3ng n\u00f3 nh\u01b0 th\u1ebf n\u00e0o th\u00ec n\u00f3 c\u0169ng kh\u00f4ng mu\u1ed1n \u201ck\u1ebft b\u1ea1n\u201d v\u1edbi kh\u00ed oxy, nh\u1eefng v\u1eadt ch\u1ea5t nh\u01b0 v\u1eady \u0111\u01b0\u01a1ng nhi\u00ean kh\u00f4ng th\u1ec3 ch\u00e1y \u0111\u01b0\u1ee3c. V\u00ec sao d\u1ea7u v\u00e0 n\u01b0\u1edbc kh\u00f4ng th\u1ec3 ho\u00e0 tan? Nh\u1ecf m\u1ea5y gi\u1ecdt d\u1ea9u v\u00e0o n\u01b0\u1edbc trong, b\u1ea1n s\u1ebd th\u1ea5y ch\u00fang l\u1eadp t\u1ee9c loang ra th\u00e0nh m\u1ed9t m\u00e0ng","m\u1ecfng n\u1ed5i l\u00ean m\u1eb7t n\u01b0\u1edbc. Cho d\u00f9 b\u1ea1n c\u00f3 khu\u1ea5y n\u01b0\u1edbc m\u1ea1nh \u0111\u1ebfn \u0111\u00e2u, ch\u00fang c\u0169ng kh\u00f4ng th\u1ec3 ho\u00e0 tan l\u00e0m m\u1ed9t. V\u00ec sao v\u1eady? Ch\u00fang ta \u0111\u00e3 bi\u1ebft n\u01b0\u1edbc su\u1ed1i c\u00f3 th\u1ec3 nh\u00f4 cao h\u01a1n mi\u1ec7ng c\u1ed1c m\u00e0 kh\u00f4ng tr\u00e0n ra ngo\u00e0i l\u00e0 v\u00ec s\u1ee9c c\u0103ng b\u1ec1 m\u1eb7t k\u00e9o ch\u1eb7t c\u00e1c ph\u1ea9n t\u1eed tr\u00ean m\u1eb7t ch\u1ea5t l\u1ecfng l\u1ea1i. S\u1ee9c c\u0103ng b\u1ec1 m\u1eb7t c\u1ee7a c\u00e1c lo\u1ea1i ch\u1ea5t l\u1ecfng kh\u00f4ng gi\u1ed1ng nhau: c\u1ee7a d\u1ea9u nh\u1ecf h\u01a1n c\u1ee7a n\u01b0\u1edbc. Khi d\u1ea9u r\u01a1i v\u00e0o m\u1eb7t n\u01b0\u1edbc, n\u01b0\u1edbc co l\u1ea1i h\u1ebft m\u1ee9c n\u00ean \u0111\u00e3 k\u00e9o d\u1ea9u d\u00e3n ra th\u00e0nh m\u1ed9t m\u00e0ng m\u1ecfng n\u1ed5i b\u00ean tr\u00ean. H\u01a1n n\u1eefa, t\u1ef7 tr\u1ecdng d\u1ea9u l\u1ea1i nh\u1ecf h\u01a1n n\u01b0\u1edbc r\u1ea5t nhi\u1ec1u, n\u00ean d\u00f9 c\u00f3 d\u00f9ng s\u1ee9c khu\u1ea5y th\u1ebf n\u00e0o, th\u00ec m\u00e0ng d\u1ea9u v\u1eabn n\u1ed5i l\u00ean tr\u00ean m\u1eb7t n\u01b0\u1edbc v\u00e0 kh\u00f4ng ho\u00e0 tan \u0111\u01b0\u1ee3c. Nh\u1eefng ch\u00fa chim th\u01b0\u1eddng xuy\u00ean ph\u1ea3i nh\u00e0o ng\u1ee5p xu\u1ed1ng n\u01b0\u1edbc \u0111\u1ec3 b\u1eaft c\u00e1 c\u0169ng d\u1ef1a v\u00e0o \u0111\u1eb7c t\u00ednh c\u1ee7a d\u1ea9u \u0111\u1ec3 b\u1ea3o v\u1ec7 m\u00ecnh. B\u1ed9 l\u00f4ng v\u0169 tr\u00ean c\u01a1 th\u1ec3 ch\u00fang th\u01b0\u1eddng xuy\u00ean \u0111\u01b0\u1ee3c \u201ctr\u00e1ng\u201d m\u1ed9t l\u1edbp d\u1ea9u m\u1ee1 \u0111\u1eb7c bi\u1ec7t ti\u1ebft ra t\u1eeb c\u00e1c l\u1ed7 ch\u00e2n l\u00f4ng. N\u1ebfu kh\u00f4ng c\u00f3 l\u1edbp d\u1ea9u \u0111\u00f3 b\u1ea3o v\u1ec7, l\u00f4ng v\u0169 s\u1ebd b\u1ecb \u01b0\u1edbt v\u00e0 kh\u00ed \u0111\u00f3 chim s\u1ebd ch\u1ebft ch\u00ecm ngay. C\u00f3 th\u1ec3 th\u1ea5y v\u00e0o l\u00fac tr\u1eddi m\u01b0a, nh\u1eefng con v\u1ecbt h\u0103ng h\u00e1i ch\u1ea1y \u0111i ch\u1ea1y l\u1ea1i m\u00e0 l\u00f4ng kh\u00f4ng h\u1ec1 b\u1ecb \u01b0\u1edbt, c\u00f2n c\u00e1c ch\u00fa g\u00e0 do tr\u00ean l\u00f4ng kh\u00f4ng c\u00f3 l\u1edbp d\u1ea9u che ph\u1ee7, n\u00ean b\u1ecb n\u01b0\u1edbc m\u01b0a th\u1ea5m \u01b0\u1edbt v\u00e0 tr\u1edf th\u00e0nh g\u00e0 \u201cr\u00f9\u201d. T\u1ea1i sao kim c\u01b0\u01a1ng l\u1ea1i r\u1eafn v\u00e0 c\u1ee9ng \u0111\u1ebfn nh\u01b0 v\u1eady? B\u1ea1n c\u00f3 th\u1ec3 ch\u01b0a t\u1eebng ngh\u0129 \u0111\u1ebfn chuy\u1ec7n than ch\u00ec \u0111en s\u00ec s\u00ec v\u00e0 \u0111\u00e1 kim c\u01b0\u01a1ng s\u00e1ng l\u1ea5p l\u00e1nh l\u00e0 anh em ru\u1ed9t, \u0111\u1ec1u l\u00e0 cacbon nguy\u00ean ch\u1ea5t t\u1ed3n t\u1ea1i trong gi\u1edbi t\u1ef1 nhi\u00ean, ch\u1ec9 c\u00f3 \u0111i\u1ec1u l\u00e0 t\u01b0\u1edbng m\u1ea1o v\u00e0 t\u00ednh c\u00e1ch c\u1ee7a ch\u00fang kh\u00e1c nhau m\u00e0 th\u00f4i. Than ch\u00ec r\u1ea5t m\u1ec1m, ch\u1ec9 c\u1ea9n g\u1ea1ch nh\u1eb9 tr\u00ean gi\u1ea5y da \u0111\u00e3 \u0111\u1ec3 l\u1ea1i v\u1ebft m\u00e0u \u0111en x\u00e1m tr\u00ean \u0111\u00f3 r\u1ed3i, ru\u1ed9t b\u00fat ch\u00ec d\u00f9ng than ch\u00ec \u0111\u1ec3 ch\u1ebf t\u1ea1o ra. Kim c\u01b0\u01a1ng l\u00e0 \u201cnh\u00e0 v\u00f4 \u0111\u1ecbch\u201d v\u1ec1 \u0111\u1ed9 c\u1ee9ng trong s\u1ed1 c\u00e1c kho\u1ea3ng v\u1eadt: nh\u00e2n vi\u00ean b\u00e1n h\u00e0ng trong c\u1eeda h\u00e0ng k\u00ednh d\u00f9ng dao n\u1ea1m kim c\u01b0\u01a1ng \u0111\u1ec3 c\u1eaft k\u00ednh, kh\u00f4ng c\u00f3 v\u1eadt n\u00e0o m\u00e0 kh\u00f4ng \u201cr\u00f3c theo dao\u201d c\u1ea3. Tr\u00ean m\u0169i khoan c\u1ee7a m\u00e1y khoan th\u0103m d\u00f2 qu\u1eb7ng c\u00f3 n\u1ea1m kim c\u01b0\u01a1ng, \u0111i\u1ec1u n\u00e0y c\u00f3 th\u1ec3 t\u0103ng nhanh t\u1ed1c \u0111\u1ed9 khoan xu\u1ed1ng \u0111\u1ea5t c\u1ee7a n\u00f3; dao kim c\u01b0\u01a1ng c\u00f2n c\u00f3 th\u1ec3 d\u00f9ng \u0111\u1ec3 gia c\u00f4ng c\u00e1c kim lo\u1ea1i c\u1ee9ng r\u1eafn kh\u00e1c n\u1eefa. Than ch\u00ec v\u00e0 kim c\u01b0\u01a1ng \u0111\u1ec1u l\u00e0 th\u00e0nh vi\u00ean c\u1ee7a gia t\u1ed9c cacbon, t\u1ea1i sao \u0111\u1ed9 c\u1ee9ng c\u1ee7a n\u00f3 l\u1ea1i kh\u00e1c xa nhau nh\u01b0 v\u1eady? Th\u00ec ra, nguy\u00ean t\u1eed cacbon trong ph\u00e2n t\u1eed than ch\u00ec x\u1ebfp theo d\u1ea1ng t\u1ea9ng, \u0111\u1ed9 li\u00ean k\u1ebft gi\u1eefa c\u00e1c t\u1ea9ng nguy\u00ean t\u1eed l\u00e0 r\u1ea5t nh\u1ecf, c\u0169ng gi\u1ed1ng nh\u01b0 m\u1ed9t b\u1ed9 t\u00fa l\u01a1 kh\u01a1 x\u1ebfp l\u1ea1i v\u1eady, ch\u00fang r\u1ea5t d\u1ec5 b\u1ecb tr\u01b0\u1ee3t v\u00e0 tung ra. C\u00f2n nguy\u00ean t\u1eed cacbon c\u1ee7a kimc\u01b0\u01a1ng l\u1ea1i l\u00e0 k\u1ebft c\u1ea5u h\u00ecnh kh\u1ed1i \u0111\u01b0\u1ee3c x\u1ebfp g\u1ecdn g\u00e0ng, m\u1ed7i nguy\u00ean t\u1eed cacbon \u0111\u1ec1u li\u00ean k\u1ebft tr\u1ef1c ti\u1ebfp v\u00e0 ch\u1eb7t ch\u1ebd v\u1edbi nguy\u00ean t\u1eed cacbon kh\u00e1c, t\u1ea1o th\u00e0nh m\u1ed9t th\u1ec3 k\u1ebft tinh ch\u1eb7t ch\u1ebd, do \u0111\u00f3 n\u00f3 r\u1ea5t c\u1ee9ng. S\u1ea3n l\u01b0\u1ee3ng c\u1ee7a kim c\u01b0\u01a1ng thi\u00ean nhi\u00ean l\u00e0 r\u1ea5t nh\u1ecf, th\u01b0\u1eddng \u1ea9n c\u01b0 \u1edf nh\u1eefng v\u00f9ng s\u00e2u","c\u1ee7a Tr\u00e1i \u0111\u1ea5t. Ch\u1ec9 c\u00f3 \u1edf nhi\u1ec7t \u0111\u1ed9 r\u1ea5t cao v\u00e0 \u00e1p l\u1ef1c l\u1edbn th\u00ec cacbon trong l\u00f2 luy\u1ec7n d\u01b0\u1edbi \u0111\u1ea5t m\u1edbi c\u00f3 kh\u1ea3 n\u0103ng th\u00f4ng qua qu\u00e1 tr\u00ecnh k\u1ebft tinh thi\u00ean nhi\u00ean \u0111\u1ec3 h\u00ecnh th\u00e0nh \u0111\u00e1 kim c\u01b0\u01a1ng qu\u00fd gi\u00e1. Do s\u1ea3n l\u01b0\u1ee3ng kim c\u01b0\u01a1ng thi\u00ean nhi\u00ean \u00edt, gi\u00e1 l\u1ea1i \u0111\u1eaft cho n\u00ean, m\u1ecdi ng\u01b0\u1eddi th\u01b0\u1eddng l\u1ee3i d\u1ee5ng nhi\u1ec7t \u0111\u1ed9 cao v\u00e0 \u00e1p su\u1ea5t cao \u0111\u1ec3 ch\u1ebf t\u1ea1o \u0111\u00e1 kim c\u01b0\u01a1ng. Nh\u1eefng t\u00ednh to\u00e1n \u0111\u00e3 ch\u1ee9ng minh r\u1eb1ng: Th\u1ec3 \u1ed5n \u0111\u1ecbnh \u1edf \u00e1p l\u1ef1c b\u00ecnh th\u01b0\u1eddng c\u1ee7a cacbon l\u00e0 t han ch\u00ec, c\u00f2n \u0111\u00e1 kim c\u01b0\u01a1ng th\u00ec ph\u1ea3i \u1edf nhi\u1ec7t \u0111\u1ed9 cao 2000 \u0111\u1ed9 C v\u00e0 \u00e1p su\u1ea5t cao 5.065 x 106 Apm\u1ed1tphe m\u1edbi \u0111\u1ea1t \u0111\u01b0\u1ee3c tr\u1ea1ng th\u00e1i \u1ed5n \u0111\u1ecbnh. Trong m\u1ea5y n\u0103m g\u1ea9n \u0111\u00e2y, con ng\u01b0\u1eddi \u0111\u00e3 bi\u1ebfn than ch\u00ec th\u00e0nh kim c\u01b0\u01a1ng trong nh\u1eefng \u0111i\u1ec1u ki\u1ec7n t\u01b0\u01a1ng t\u1ef1. V\u00ec sao khi t\u00e0u \u0111i v\u1ec1 ph\u00eda T\u00e2y, m\u1ed9t ng\u00e0y d\u00e0i h\u01a1n 24 gi\u1edd? Ng\u00e0y 20\/09\/1519, n\u0103m chi\u1ebfc t\u00e0u c\u1ee7a T\u00e2y Ban Nha do nh\u00e0 th\u00e1m hi\u1ec3m Magelland\u1eabn \u0111\u1ea9u r\u1eddi c\u1ea3ng Sanlucar \u0111i v\u1ec1 ph\u00eda T\u00e2y, b\u1eaft \u0111\u1ea9u cu\u1ed9c h\u00e0nh tr\u00ecnh v\u00f2ng quanh Tr\u00e1i \u0111\u1ea5t. Sau g\u1ea9n 3 n\u0103m, ch\u1ec9 c\u00f2n l\u1ea1i m\u1ed9t chi\u1ebfc t\u00e0u v\u1ec1 t\u1edbi qu\u1ea9n \u0111\u1ea3o M\u0169i Xanh, c\u1ef1c T\u00e2y Ch\u00e2u Phi. Nh\u1eadt k\u00fd tr\u00ean t\u00e0u ghi l\u1ea1i \u201cNg\u00e0y 09\/07\/1522, t\u1edbi qu\u1ea9n \u0111\u1ea3o \u201cM\u0169i Xanh\u201d. Nh\u01b0ng \u1edf tr\u00ean \u0111\u1ea3o, h\u00f4m \u0111\u00f3 l\u1ea1i l\u00e0 m\u00f9ng 10. C\u00e1c thu\u1ef7 th\u1ee7 tr\u00ean t\u00e0u ng\u00e0y n\u00e0o c\u0169ng ghi nh\u1eadt k\u00fd n\u00ean h\u1ecd kh\u00f4ng tin l\u1eddi d\u00e2n \u0111\u1ecba ph\u01b0\u01a1ng. V\u1eady r\u1ed1t c\u1ee5c h\u00f4m \u0111\u00f3 l\u00e0 m\u00f9ng 9 hay m\u00f9ng 10? Tr\u00ean th\u1ef1c t\u1ebf, h\u00f4m \u0111\u00f3 l\u00e0 m\u00f9ng 10. C\u00e1c thu\u1ef7 th\u1ee7 \u0111\u00e2u bi\u1ebft r\u1eb1ng, h\u1ecd \u0111\u00e3 \u0111\u00e1nh m\u1ea5t m\u1ed9t ng\u00e0y tr\u00ean \u0111\u01b0\u1eddng \u0111i, v\u00ec h\u1ecd \u0111\u00e3 b\u1eaft \u0111\u1ea9u \u0111i v\u1ec1 ph\u00eda T\u00e2y \u0111\u1ec3 \u0111i v\u00f2ng quanh Tr\u00e1i \u0111\u1ea5t. Tr\u00e1i \u0111\u1ea5t quay t\u1eeb T\u00e2y sang \u0110\u00f4ng. \u0110o\u00e0n t\u00e0u c\u1ee7a Magellan\u0111i v\u1ec1 ph\u00eda T\u00e2y, v\u00f4 h\u00ecnh dung h\u1ecd \u0111\u00e3 ch\u01a1i tr\u00f2 \u201c\u0111u\u1ed5i b\u1eaft M\u1eb7t tr\u1eddi\u201d. Ban ng\u00e0y, h\u1ecd kh\u00f4ng ng\u1eebng \u0111u\u1ed5i theo M\u1eb7t tr\u1eddi \u0111ang l\u1eb7n v\u1ec1 ph\u00eda T\u00e2y, ban \u0111\u00eam h\u1ecd l\u1ea1i tr\u00e1nh xa M\u1eb7t tr\u1eddi m\u1ecdc \u1edf ph\u00eda \u0110\u00f4ng, v\u00e0 nh\u01b0 v\u1eady ng\u00e0y v\u00e0 \u0111\u00eam tr\u00ean t\u00e0u \u0111\u01b0\u1ee3c k\u00e9o d\u00e0i ra. Theo t\u00ednh to\u00e1n c\u1ee7a c\u00e1c nh\u00e0 khoa h\u1ecdc, m\u1ed7i ng\u00e0y \u0111\u00eam tr\u00ean t\u00e0u d\u00e0i h\u01a1n 1,5 ph\u00fat so v\u1edbi m\u1ed9t ng\u00e0y b\u00ecnh th\u01b0\u1eddng c\u00f3 24 gi\u1edd. V\u00ec m\u1ed9t ph\u00fat r\u01b0\u1ee1i qu\u00e1 ng\u1eafn v\u00e0 tr\u00ean t\u00e0u kh\u00f4ng c\u00f3 \u0111\u1ed3ng h\u1ed3 chu\u1ea9n n\u00ean c\u00e1c thu\u1ef7 th\u1ee7 kh\u00f4ng ph\u00e1t hi\u1ec7n ra. \u0110o\u00e0n t\u00e0u \u0111i g\u1ea9n 3 n\u0103m, m\u1ed7i ng\u00e0y d\u00e0i th\u00eam 1,5 ph\u00fat, c\u1ed9ng l\u1ea1i trong 3 n\u0103m \u0111\u00fang b\u1eb1ng 1 ng\u00e0y. M\u1ed9t ng\u00e0y k\u1ef3 l\u1ea1 \u0111\u00f3 \u0111\u00e3 l\u1eb7ng l\u1ebd bi\u1ebfn m\u1ea5t trong chuy\u1ebfn \u0111i c\u1ee7a \u0111o\u00e0n t\u00e0u. T\u1ea5t nhi\u00ean, n\u1ebfu nh\u01b0 \u0111o\u00e0n t\u00e0u \u0111i v\u1ec1 ph\u00eda \u0110\u00f4ng, sau 3 n\u0103m h\u1ecd s\u1ebd d\u00f4i ra 1 ng\u00e0y. T\u1ed1c \u0111\u1ed9 c\u1ee7a t\u00e0u thuy\u1ec1n m\u1ea5y tr\u0103m n\u0103m tr\u01b0\u1edbc ch\u1eadm h\u01a1n nhi\u1ec1u so v\u1edbi t\u00e0u vi\u1ec5n d\u01b0\u01a1ng v\u00e0 m\u00e1y bay ph\u1ea3n l\u1ef1c ng\u00e0y nay. Khi c\u00e1c t\u00e0u vi\u1ec5n d\u01b0\u01a1ng v\u00e0 m\u00e1y bay \u0111i v\u1ec1 ph\u00eda T\u00e2y, m\u1ed7i ng\u00e0y kh\u00f4ng d\u00e0i ra 1,5 ph\u00fat m\u00e0 d\u00e0i th\u00eam m\u1ea5y ch\u1ee5c ph\u00fat, th\u1eadm ch\u00ed m\u1ea5y gi\u1edd, b\u1edfi l\u1ebd ch\u00fang \u201c\u0111u\u1ed5i theo\u201d M\u1eb7t tr\u1eddi v\u1edbi t\u1ed1c \u0111\u1ed9 r\u1ea5t nhanh. V\u00ec v\u1eady c\u00e1c nh\u00e0 h\u00e0ng h\u1ea3i v\u00e0 h\u00e0ng kh\u00f4ng khi t\u00ednh th\u1eddi gian h\u00e0nh tr\u00ecnh bu\u1ed9c ph\u1ea3i tr\u1eeb b\u1edbt ho\u1eb7c c\u1ed9ng th\u00eam kho\u1ea3ng th\u1eddi gian t\u0103ng th\u00eam ho\u1eb7c m\u1ea5t \u0111i \u0111\u00f3. T\u1ea1i sao thuy\u1ec1n bu\u1ed3m c\u00f3 th\u1ec3 ch\u1ea1y ng\u01b0\u1ee3c gi\u00f3?","V\u1edbi ng\u01b0\u1eddi kh\u00f4ng c\u00f3 kinh nghi\u1ec7m \u0111i bi\u1ec3n ho\u1eb7c kh\u00f4ng h\u1ecdc v\u1eadt l\u00fd th\u00ec vi\u1ec7c thuy\u1ec1n bu\u1ed3m c\u00f3 th\u1ec3 b\u01a1i ng\u01b0\u1ee3c gi\u00f3 th\u1eadt kh\u00f3 t\u01b0\u1edfng t\u01b0\u1ee3ng. Th\u1ef1c ra, thuy\u1ec1n kh\u00f4ng th\u1ec3 \u0111i ng\u01b0\u1ee3c h\u01b0\u1edbng gi\u00f3 ho\u00e0n to\u00e0n, nh\u01b0ng ch\u1ec7ch m\u1ed9t g\u00f3c nh\u1ecf th\u00ec c\u00f3 th\u1ec3. Mu\u1ed1n hi\u1ec3u v\u1ea5n \u0111\u1ec1, ch\u00fang ta h\u00e3y t\u00ecm hi\u1ec3u l\u1ef1c gi\u00f3 t\u00e1c d\u1ee5ng l\u00ean bu\u1ed3m nh\u01b0 th\u1ebf n\u00e0o? Nhi\u1ec1u ng\u01b0\u1eddi ngh\u0129 r\u1eb1ng, c\u00e1nh bu\u1ed3m \u0111\u01b0\u1ee3c \u0111\u1ea9y theo chi\u1ec1u gi\u00f3 th\u1ed5i, nh\u01b0ng th\u1ef1c t\u1ebf kh\u00f4ng ph\u1ea3i v\u1eady: D\u00f9 gi\u00f3 c\u00f3 th\u1ed5i theo h\u01b0\u1edbng n\u00e0o th\u00ec n\u00f3 c\u0169ng ch\u1ec9 \u0111\u1ea9y bu\u1ed3m theo ph\u01b0\u01a1ng th\u1eb3ng g\u00f3c v\u1edbi m\u1eb7t ph\u1eb3ng c\u1ee7a bu\u1ed3m m\u00e0 th\u00f4i! (h\u00ecnh 1) Trong h\u00ecnh 1, \u0111\u01b0\u1eddng th\u1eb3ng AB bi\u1ec3u di\u1ec5n c\u00e1nh bu\u1ed3m. R l\u00e0 l\u1ef1c \u0111\u1ea9y c\u1ee7a gi\u00f3 t\u00e1c d\u1ee5ng v\u00e0o c\u00e1nh bu\u1ed3m. Ta ph\u00e2n t\u00edch l\u1ef1c R th\u00e0nh hai ph\u1ea9n, g\u1ed3m l\u1ef1c Q vu\u00f4ng g\u00f3c v\u1edbi c\u00e1nh bu\u1ed3m v\u00e0 l\u1ef1c P h\u01b0\u1edbng d\u1ecdc theo n\u00f3. V\u00ec s\u1ef1 ma s\u00e1t c\u1ee7a gi\u00f3 v\u1edbi c\u00e1nh bu\u1ed3m l\u00e0 kh\u00f4ng \u0111\u00e1ng k\u1ec3, n\u00ean l\u1ef1c P ch\u1ec9 tr\u01b0\u1ee3t qua ch\u1ee9 kh\u00f4ng t\u00e1c d\u1ee5ng g\u00ec t\u1edbi bu\u1ed3m. Ch\u1ec9 c\u00f3 l\u1ef1c Q \u0111\u1ea9y c\u00e1nh bu\u1ed3m theo h\u01b0\u1edbng vu\u00f4ng g\u00f3c v\u1edbi m\u1eb7t bu\u1ed3m. N\u1ebfu hi\u1ec3u \u0111\u01b0\u1ee3c v\u1ea5n \u0111\u1ec1 tr\u00ean, b\u1ea1n c\u0169ng c\u00f3 th\u1ec3 hi\u1ec3u t\u1ea1i sao thuy\u1ec1n c\u00f3 bu\u1ed3m c\u00f3 th\u1ec3 \u0111i ng\u01b0\u1ee3c m\u1ed9t g\u00f3c nh\u1ecdn v\u1edbi chi\u1ec1u gi\u00f3. (h\u00ecnh 2) Gi\u1ea3 s\u1eed \u0111o\u1ea1n th\u1eb3ng KK bi\u1ec3u di\u1ec5n chi\u1ec1u d\u00e0i c\u1ee7a thuy\u1ec1n. \u0110\u01b0\u1eddng th\u1eb3ng AB bi\u1ec3u di\u1ec5n c\u00e1nh bu\u1ed3m. Ng\u01b0\u1eddi ta h\u01b0\u1edbng c\u00e1nh bu\u1ed3m sao cho m\u1eb7t ph\u1eb3ng c\u1ee7a n\u00f3 chia \u0111\u00f4i g\u00f3c gi\u1eefa ph\u01b0\u01a1ng c\u1ee7a l\u00f2ng thuy\u1ec1n v\u00e0 ph\u01b0\u01a1ng c\u1ee7a gi\u00f3. B\u00e2y gi\u1edd b\u1ea1n h\u00e3y theo d\u00f5i bi\u1ec3u \u0111\u1ed3 ph\u00e2n t\u00edch l\u1ef1c \u1edf h\u00ecnh 2, trong \u0111\u00f3 Q l\u00e0 \u00e1p l\u1ef1c c\u1ee7a gi\u00f3 t\u00e1c d\u1ee5ng l\u00ean c\u00e1nh bu\u1ed3m. Nh\u01b0 \u0111\u00e3 ph\u00e2n t\u00edch \u1edf h\u00ecnh 1, l\u1ef1c Q ph\u1ea3i vu\u00f4ng g\u00f3c v\u1edbi c\u00e1nh bu\u1ed3m. L\u1ef1c Q l\u1ea1i c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c chia th\u00e0nh hai l\u1ef1c: l\u1ef1c S d\u1ecdc theo m\u0169i thuy\u1ec1n v\u00e0 l\u1ef1c R vu\u00f4ng g\u00f3c v\u1edbi chi\u1ec1u d\u00e0i thuy\u1ec1n. V\u00ec chuy\u1ec3n \u0111\u1ed9ng c\u1ee7a thuy\u1ec1n theo h\u01b0\u1edbng R b\u1ecb n\u01b0\u1edbc c\u1ea3n l\u1ea1i r\u1ea5t m\u1ea1nh (thuy\u1ec1n bu\u1ed3m th\u01b0\u1eddng c\u00f3 l\u00f2ng r\u1ea5t s\u00e2u), n\u00ean l\u1ef1c R ho\u00e0n to\u00e0n b\u1ecb l\u1ef1c c\u1ea3n c\u1ee7a n\u01b0\u1edbc c\u00e2n b\u1eb1ng. Do \u0111\u00f3, ch\u1ec9 c\u00f3 S l\u00e0 l\u1ef1c h\u01b0\u1edbng t\u1edbi ph\u00eda tr\u01b0\u1edbc, gi\u00fap thuy\u1ec1n c\u00f3 th\u1ec3 chuy\u1ec3n \u0111\u1ed9ng ng\u01b0\u1ee3c m\u1ed9t g\u00f3c nh\u1ecf v\u1edbi chi\u1ec1u gi\u00f3. (h\u00ecnh 3) Th\u1ef1c t\u1ebf (h\u00ecnh 3), \u0111\u1ec3 \u0111\u01b0a thuy\u1ec1n t\u1eeb \u0111i\u1ec3m A \u0111\u1ebfn \u0111i\u1ec3m B, ng\u01b0\u1ee3c chi\u1ec1u gi\u00f3, ng\u01b0\u1eddi ta ph\u1ea3i h\u01b0\u1edbng thuy\u1ec1n bu\u1ed3m \u0111i theo \u0111\u01b0\u1eddng zic zac. V\u00ec sao ray tr\u00ean \u0111\u01b0\u1eddng s\u1eaft ph\u1ea3i l\u00e0m th\u00e0nh h\u00ecnh ch\u1eef \u201ci\u201d?","T\u1ea9u ho\u1ea3 ph\u1ea3i ch\u1ea1y tr\u00ean hai thanh ray s\u1eaft \u0111\u1eb7t song song v\u1edbi nhau, d\u01b0\u1edbi nh\u1eefng thanh ray n\u00e0y, c\u00e1ch m\u1ed9t kho\u1ea3ng nh\u1ea5t \u0111\u1ecbnh \u0111\u1ec1u \u0111\u1eb7t m\u1ed9t t\u1ea5m g\u1ed7 d\u1ea9y to vu\u00f4ng v\u1ee9c. N\u00f3 s\u1ebd l\u00e0m cho n\u1ec1n \u0111\u01b0\u1eddng c\u00f3 th\u1ec3 ch\u1ecbu \u0111\u01b0\u1ee3c \u00e1p l\u1ef1c n\u1eb7ng c\u1ee7a t\u1ea9u. Kh\u00f4ng bi\u1ebft b\u1ea1n c\u00f3 ch\u00fa \u00fd kh\u00f4ng, thanh ray tr\u00ean \u0111\u01b0\u1eddng s\u1eaft kh\u00f4ng ph\u1ea3i l\u00e0 h\u00ecnh \u201cvu\u00f4ng g\u00f3c\u201d \u0111\u01a1n gi\u1ea3n m\u00e0 l\u00e0 h\u00ecnh ch\u1eef I v\u1edbi ki\u1ec3u thi\u1ebft k\u1ebf tr\u00ean h\u1eb9p d\u01b0\u1edbi r\u1ed9ng. \u0110i\u1ec1u n\u00e0y l\u00e0 t\u1ea1i sao? M\u1ecdi ng\u01b0\u1eddi \u0111\u1ec1u bi\u1ebft tr\u1ecdng t\u1ea3i c\u1ee7a xe l\u1eeda r\u1ea5t l\u1edbn. \u0110\u1ec3 c\u00f3 th\u1ec3 ch\u1ecbu \u0111\u01b0\u1ee3c \u00e1p l\u1ef1c c\u1ee7a xe c\u00f3 tr\u1ecdng t\u1ea3i l\u1edbn, m\u1eb7t tr\u00ean c\u1ee7a \u0111\u01b0\u1eddng ray c\u1ea9n c\u00f3 \u0111\u1ed9 r\u1ed9ng v\u00e0 \u0111\u1ed9 d\u00e0y nh\u1ea5t \u0111\u1ecbnh; C\u0169ng nh\u01b0 v\u1eady, \u0111\u1ec3 n\u00e2ng cao t\u00ednh \u1ed5n \u0111\u1ecbnh c\u1ee7a \u0111\u01b0\u1eddng ray, m\u1eb7t \u0111\u00e1y c\u1ee7a \u0111\u01b0\u1eddng ray c\u0169ng c\u1ea9n c\u00f3 \u0111\u1ed9 r\u1ed9ng nh\u1ea5t \u0111\u1ecbnh; H\u01a1n n\u1eefa, \u0111\u1ec3 \u0103n kh\u1edbp v\u1edbi b\u00e1nh xe, \u0111\u01b0\u1eddng ray l\u1ea1i ph\u1ea3i c\u00f3 \u0111\u1ed9 cao nh\u1ea5t \u0111\u1ecbnh. \u0110\u01b0\u1eddng ray h\u00ecnh ch\u1eef \u201cI\u201d v\u1eeba \u0111\u1ee7 \u0111\u00e1p \u1ee9ng \u0111\u1ea9y \u0111\u1ee7 ba y\u00eau c\u1ea9u tr\u00ean, m\u00e0 x\u00e9t t\u1eeb quan \u0111i\u1ec3m c\u1ee7a v\u1eadt li\u1ec7u c\u01a1 h\u1ecdc th\u00ec \u0111\u01b0\u1eddng ray ki\u1ec3u n\u00e0y c\u00f3 c\u01b0\u1eddng \u0111\u1ed9 cao nh\u1ea5t, c\u00f3 th\u1ec3 t\u1eadn d\u1ee5ng nguy\u00ean li\u1ec7u m\u1ed9t c\u00e1ch h\u1ee3p l\u00fd. Do v\u1eady m\u1eb7t c\u1eaft ch\u1eef \u201cI\u201d \u0111\u01b0\u1ee3c ch\u1ecdn l\u00e0 m\u1eb7t c\u1eaft \u0111\u01b0\u1eddng ray t\u1ed1t nh\u1ea5t. \u0110\u01b0\u1eddng ray h\u00ecnh ch\u1eef \u201cI\u201d \u0111\u00e3 \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng tr\u00ean \u0111\u01b0\u1eddng s\u1eaft tr\u00ean \u0111\u01b0\u1eddng s\u1eaft tr\u00ean m\u1ed9t tr\u0103m n\u0103m. Ngo\u00e0i vi\u1ec7c \u0111\u1ec3 th\u00edch \u1ee9ng v\u1edbi s\u1ef1 t\u0103ng tr\u1ecdng t\u1ea3i c\u1ee7a \u0111\u1ea9u m\u00e1y v\u00e0 n\u00e2ng cao t\u1ed1c \u0111\u1ed9 c\u1ee7a t\u00e0u th\u00ec ngo\u00e0i vi\u1ec7c thi\u1ebft k\u1ebf t\u0103ng m\u1eb7t c\u1eaft c\u1ee7a \u0111\u01b0\u1eddng ray v\u00e0 c\u1ea3i ti\u1ebfn c\u00e1c chi ti\u1ebft nh\u1ecf c\u1ee7a c\u00e1c b\u1ed9 ph\u1eadn, h\u00ecnh d\u1ea1ng c\u1ee7a \u0111\u01b0\u1eddng ray h\u1ea9u nh\u01b0 kh\u00f4ng c\u00f3 g\u00ec thay \u0111\u1ed5i. Nh\u01b0ng \u0111\u00e2y c\u0169ng kh\u00f4ng ph\u1ea3i l\u00e0 n\u00f3i h\u00ecnh d\u00e1ng c\u1ee7a \u0111\u01b0\u1eddng ray v\u0129nh vi\u1ec5n s\u1ebd kh\u00f4ng thay \u0111\u1ed5i. C\u00e1c k\u1ef9 s\u01b0 \u0111\u01b0\u1eddng s\u1eaft v\u1eabn \u0111ang nghi\u00ean c\u1ee9u v\u1ea5n \u0111\u1ec1 n\u00e0y, hy v\u1ecdng c\u00f3 th\u1ec3 t\u00ecm ra h\u00ecnh d\u00e1ng c\u1ee7a \u0111\u01b0\u1eddng ray h\u1ee3p l\u00fd h\u01a1n v\u00e0 kinh t\u1ebf h\u01a1n. \u0110\u1ed9 r\u1ed9ng c\u1ee7a \u0111\u01b0\u1eddng s\u1eaft \u0111\u1ec1u gi\u1ed1ng nhau ph\u1ea3i kh\u00f4ng? Ch\u00fang ta bi\u1ebft r\u1eb1ng xe l\u1eeda lu\u00f4n ch\u1ea1y theo hai \u0111\u01b0\u1eddng ray \u0111\u1eb7t song song. Do hai b\u00ean tr\u00e1i v\u00e0 ph\u1ea3i c\u1ee7a t\u1ea9u ho\u1ea3 t\u01b0\u01a1ng \u0111\u1ed1i c\u1ed1 \u0111\u1ecbnh v\u1edbi kho\u1ea3ng c\u00e1ch gi\u1eefa b\u00e1nh xe, do v\u1eady kho\u1ea3ng c\u00e1ch th\u1eb3ng gi\u1eefa hai thanh ray kho\u1ea3ng c\u00e1ch ray c\u0169ng ph\u1ea3i c\u1ed1 \u0111\u1ecbnh kh\u00f4ng \u0111\u1ed5i, n\u00f3 v\u00e0 kho\u1ea3ng c\u00e1chc\u1ee7a hai b\u00e1nh t\u1ea9u ho\u1ea3 ph\u1ea3i v\u1eeba v\u1eb7n, \u0103n kh\u1edbp v\u1edbi nhau, ch\u1ec9 \u1edf ch\u1ed7 ngo\u1eb7t c\u1ee7a \u0111\u01b0\u1eddng s\u1eaft th\u00ec kho\u1ea3ng c\u00e1ch ray m\u1edbi h\u01a1i r\u1ed9ng v\u00e0 \u0111\u1ec3 tr\u00e1nh l\u00e0m tr\u1eadt b\u00e1nh. Kho\u1ea3ng c\u00e1ch ray ti\u00eau chu\u1ea9n c\u1ee7a \u0111\u01b0\u1eddng s\u1eaft l\u00e0 1435 mm. Ngu\u1ed3n g\u1ed1c c\u1ee7a n\u00f3 c\u00f2n l\u00e0 m\u1ed9t c\u00e2u chuy\u1ec7n! H\u01a1n 2500 n\u0103m tr\u01b0\u1edbc, v\u01b0\u01a1ng qu\u1ed1c La M\u00e3 c\u1ed5 ph\u00e1i m\u1ed9t \u0111\u1ea1i qu\u00e2n sang x\u00e2m l\u01b0\u1ee3c n\u01b0\u1edbc Anh. V\u00f4 s\u1ed1 chi\u1ebfn xa \u0111\u00e3 tr\u00e0n qua m\u1ed9t v\u00f9ng \u0111\u1ea5t r\u1ed9ng l\u1edbn c\u1ee7a Anh Qu\u1ed1c, \u0111\u1ec3 l\u1ea1i nh\u1eefng v\u1ebft b\u00e1nh xe r\u1ea5t s\u00e2u tr\u00ean \u0111\u01b0\u1eddng. L\u00fac \u0111\u00f3, lo\u1ea1i b\u00e1nh xe hai b\u00e1nh n\u00e0y \u0111\u00e3 \u0111\u1ec3 l\u1ea1i v\u1ec7t b\u00e1nh xe c\u00f3 kho\u1ea3ng c\u00e1ch gi\u1eefa hai b\u00e1nh kho\u1ea3ng 1435 mm l\u00e0m cho xe ng\u1ef1a b\u1ed1n b\u00e1nh c\u1ee7a Anh r\u1ea5t d\u1ec5 b\u1ecb sa l\u1ea9y xu\u1ed1ng. \u0110\u1ec3 nh\u1eefng xe c\u1ee7a m\u00ecnh c\u00f3 th\u1ec3 di chuy\u1ec3n thu\u1eadn l\u1ee3i l\u00ean ph\u00eda tr\u01b0\u1edbc theo c\u00e1c v\u1ebft b\u00e1nh xe tr\u0169ng xu\u1ed1ng r\u1ea5t s\u00e2u n\u00e0y, ng\u01b0\u1eddi Anh \u0111\u00e3 quy\u1ebft \u0111\u1ecbnh c\u1ea3i t\u1ea1o kho\u1ea3ng c\u00e1ch c\u1ee7a t\u1ea5t c\u1ea3 c\u00e1c b\u00e1nh xe ng\u1ef1a th\u00e0nh c\u00f9ng m\u1ed9t \u0111\u1ed9 r\u1ed9ng 1435","mm. K\u1ebft qu\u1ea3, truy\u1ec1n th\u1ed1ng n\u00e0y l\u1ea1i \u0111\u01b0\u1ee3c l\u00e0m ti\u1ebfp nh\u01b0 c\u0169. \u0110\u1ebfn n\u0103m 1825, tuy\u1ebfn \u0111\u01b0\u1eddng s\u1eaft \u0111\u1ea9u ti\u00ean tr\u00ean th\u1ebf gi\u1edbi \u0111\u01b0\u1ee3c kh\u00e1nh th\u00e0nh t\u1ea1i n\u01b0\u1edbc Anh. Kho\u1ea3ng c\u00e1ch ray c\u1ee7a \u0111\u01b0\u1eddng s\u1eaft c\u0169ng \u0111\u01b0\u1ee3c \u0111\u1ecbnh r\u00f5 r\u00e0ng l\u00e0 1435 mm. Sau \u0111\u00f3, c\u00f9ng v\u1edbi s\u1ef1 ph\u00e1t tri\u1ec3n c\u1ee7a c\u00e1ch m\u1ea1ng c\u00f4ng nghi\u1ec7p, r\u1ea5t nhi\u1ec1u qu\u1ed1c gia c\u0169ng ti\u1ebfp t\u1ee5c x\u00e2y d\u1ef1ng \u0111\u01b0\u1eddng s\u1eaft, m\u00e0 l\u1ea1i t\u1edbi t\u1ea5p mang kho\u1ea3ng c\u00e1ch \u0111\u01b0\u1eddng ray c\u1ee7a \u0111\u01b0\u1eddng s\u1eaft Anh v\u1ec1 n\u01b0\u1edbc. N\u0103m 1937, Hi\u1ec7p h\u1ed9i \u0111\u01b0\u1eddng s\u1eaft Qu\u1ed1c t\u1ebf qui \u0111\u1ecbnh: Kho\u1ea3ng c\u00e1ch \u0111\u01b0\u1eddng ray ti\u00eau chu\u1ea9n c\u1ee7a \u0111\u01b0\u1eddng s\u1eaft l\u00e0 1435 mm. V\u1eady th\u00ec c\u00f3 ph\u1ea3i t\u1ea5t c\u1ea3 c\u00e1c \u0111\u01b0\u1eddng s\u1eaft tr\u00ean th\u1ebf gi\u1edbi \u0111\u1ec1u d\u00f9ng kho\u1ea3ng c\u00e1ch ray ti\u00eau chu\u1ea9n n\u00e0y ph\u1ea3i kh\u00f4ng? Th\u1ef1c ra, do t\u00ednh \u0111\u1eb7c th\u00f9 c\u1ee7a t\u00ecnh h\u00ecnh ph\u00e1t tri\u1ec3n \u0111\u01b0\u1eddng ray t\u1eebng th\u1eddi k\u1ef3 c\u1ee7a t\u1eebng n\u01b0\u1edbc, kh\u00f4ng \u00edt n\u01b0\u1edbc s\u1eed d\u1ee5ng \u0111\u01b0\u1eddng ray h\u1eb9p ho\u1eb7c \u0111\u01b0\u1eddng ray r\u1ed9ng nh\u1ecf h\u01a1n ho\u1eb7c v\u01b0\u1ee3t qu\u00e1 1435 mm. V\u00ed d\u1ee5, kho\u1ea3ng c\u00e1ch ray \u0111\u01b0\u1eddng s\u1eaft c\u1ee7a Li\u00ean X\u00f4 c\u0169 bi\u1ebfn th\u00e0nh 1524 mm, \u0111\u01b0\u1eddng ray r\u1ed9ng c\u1ee7a T\u00e2y Ban Nha \u0111\u1ea1t \u0111\u1ebfn 1667 mm; C\u00f2n tr\u01b0\u1edbc \u0111\u00e2y, kho\u1ea3ng c\u00e1ch ray \u0111\u01b0\u1eddng s\u1eaft Nh\u1eadt B\u1ea3n l\u1ea1i t\u01b0\u01a1ng \u0111\u1ed1i h\u1eb9p, ch\u1ec9 c\u00f3 1067 mm. H\u1ea9u h\u1ebft \u0111\u01b0\u1eddng s\u1eaft trong m\u1ea1ng l\u01b0\u1edbi \u0111\u01b0\u1eddng s\u1eaft c\u1ee7a Trung Qu\u1ed1c \u0111\u1ec1u s\u1eed d\u1ee5ng kho\u1ea3ng c\u00e1ch ray ti\u00eau chu\u1ea9n qu\u1ed1c t\u1ebf l\u00e0 1435 mm. Nh\u01b0ng \u1edf m\u1ed9t s\u1ed1 v\u00f9ng nh\u01b0 bi\u00ean gi\u1edbi Trung Mi\u1ebfn, Trung Vi\u1ec7t tr\u01b0\u1edbc \u0111\u00e2y \u0111\u00e3 t\u1eebng tr\u1ea3i \u0111\u01b0\u1eddng s\u1eaft kho\u1ea3ng c\u00e1ch ray h\u1eb9p, d\u00f9ng cho t\u1ea9u ho\u1ea3 nh\u1ecf c\u1ee7a \u0111\u1ecba ph\u01b0\u01a1ng v\u1eadn h\u00e0nh, \u0111\u00e2y l\u00e0 t\u00ecnh h\u00ecnh c\u1ee5c b\u1ed9 trong th\u1eddi k\u1ef3 l\u1ecbch s\u1eed \u0111\u1eb7c th\u00f9. Ngo\u00e0i ra, v\u00f9ng \u0110\u00f4ng B\u1eafc c\u1ee7a Trung Qu\u1ed1c \u0111\u00e3 x\u00e2y d\u1ef1ng m\u1ed9t v\u00e0i tuy\u1ebfn \u0111\u01b0\u1eddng s\u1eaft trong r\u1eebng s\u00e2u, do chuy\u00ean d\u00f9ng \u0111\u1ec3 v\u1eadn chuy\u1ec3n g\u1ed7, l\u1ef1c k\u00e9o d\u1eabn t\u01b0\u01a1ng \u0111\u1ed1i nh\u1ecf, t\u1ea9u \u0111\u01b0\u1ee3c thi\u1ebft k\u1ebf \u0111\u1ed9 r\u1ed9ng t\u01b0\u01a1ng \u0111\u1ed1i h\u1eb9p, do \u0111\u00f3 ph\u1ed5 bi\u1ebfn s\u1eed d\u1ee5ng \u0111\u01b0\u1eddng s\u1eaft ray h\u1eb9p 762 mm. T\u1ea1i sao xe l\u1eeda c\u1ea7n ch\u1ea1y tr\u00ean \u0111\u01b0\u1eddng ray? M\u1ed9t \u00f4 t\u00f4 t\u1ea3i n\u1ebfu \u0111\u1ed7 tr\u00ean m\u1eb7t \u0111\u01b0\u1eddng \u0111\u00e1 v\u1ee5n, 15 ng\u01b0\u1eddi m\u1edbi \u0111\u1ea9y n\u00f3 \u0111i \u0111\u01b0\u1ee3c. Nh\u01b0ng n\u1ebfu m\u1ed9t toa xe l\u1eeda c\u00f3 c\u00f9ng tr\u1ecdng l\u01b0\u1ee3ng \u0111\u1ed7 tr\u00ean \u0111\u01b0\u1eddng ray th\u00e9p, ch\u1ec9 2 ng\u01b0\u1eddi l\u00e0 \u0111\u1ee7 \u0111\u1ea9y n\u00f3 ti\u1ebfn l\u00ean. V\u1ea5n \u0111\u1ec1 m\u1ea5u ch\u1ed1t \u1edf \u0111\u00e2y l\u00e0 s\u1ee9c c\u1ea3n l\u0103n. \u0110\u1ea1i l\u01b0\u1ee3ng n\u00e0y ch\u00eanh nhau t\u1edbi 7,5 l\u1ea9n \u1edf hai lo\u1ea1i xe. Khi \u0111i xe \u0111\u1ea1p tr\u00ean \u0111\u01b0\u1eddng r\u1ea3i nh\u1ef1a ph\u1eb3ng l\u00ec b\u1ea1n s\u1ebd c\u1ea3m th\u1ea5y r\u1ea5t d\u1ec5 ch\u1ecbu, c\u00f2n khi \u0111i xe tr\u00ean \u0111\u01b0\u1eddng \u0111\u00e1 v\u1ee5n g\u1ed3 gh\u1ec1 kh\u1ea5p kh\u1ec3nh b\u1ea1n s\u1ebd c\u1ea3m th\u1ea5y t\u1ed1n s\u1ee9c. T\u01b0\u01a1ng t\u1ef1, khi l\u1ed1p xe \u0111\u1ea1p b\u01a1m c\u0103ng, ng\u1ed3i l\u00ean xe c\u1ea3m th\u1ea5y d\u1ec5 ch\u1ecbu. Khi l\u1ed1p non h\u01a1i, \u0111\u1ea1p xe s\u1ebd t\u1ed1n s\u1ee9c. V\u1ea5n \u0111\u1ec1 c\u0169ng v\u1eabn l\u00e0 s\u1ee9c c\u1ea3n l\u0103n. \u0110\u01b0\u1eddng nh\u1ef1a ph\u1eb3ng l\u00ec v\u00e0 l\u1ed1p xe \u0111\u1ea1p b\u01a1m c\u0103ng th\u00ec s\u1ee9c c\u1ea3n l\u0103n nh\u1ecf, ng\u01b0\u1eddi ng\u1ed3i tr\u00ean xe \u0111\u1ea1p c\u1ea3m th\u1ea5y d\u1ec5 ch\u1ecbu. V\u00ec v\u1eady gi\u1ea3m s\u1ee9c c\u1ea3n l\u0103n l\u00e0 m\u1ed9t kh\u00e2u ch\u1ee7 y\u1ebfu trong vi\u1ec7c n\u00e2ng cao hi\u1ec7u qu\u1ea3 v\u1eadn chuy\u1ec3n. Nh\u1eefng xe l\u1eeda \u0111\u1ea9u ti\u00ean l\u00e0 nh\u1eefng xe b\u00e1nh g\u1ed7 ch\u1ea1y tr\u00ean \u0111\u01b0\u1eddng ray g\u1ed7 do ng\u1ef1a k\u00e9o, s\u1ee9c c\u1ea3n l\u0103n r\u1ea5t l\u1edbn. Sau \u0111\u00f3, t\u1eebng b\u01b0\u1edbc c\u1ea3i ti\u1ebfn, cho \u0111\u1ebfn c\u00e1ch \u0111\u00e2y h\u01a1n 100 n\u0103m, khi ph\u00e1t minh ra m\u00e1y h\u01a1i n\u01b0\u1edbc th\u00ec b\u00e1nh xe v\u00e0 \u0111\u01b0\u1eddng ray m\u1edbi \u0111\u01b0\u1ee3c ch\u1ebf t\u1ea1o b\u1eb1ng th\u00e9p, do v\u1eady s\u1ee9c c\u1ea3n l\u0103n gi\u1ea3m \u0111i r\u1ea5t nhi\u1ec1u. M\u1eb7t kh\u00e1c, do b\u1ea3n th\u00e2n xe l\u1eeda r\u1ea5t n\u1eb7ng, n\u1ebfu xe l\u1eeda tr\u1ef1c ti\u1ebfp ch\u1ea1y tr\u00ean \u0111\u01b0\u1eddng \u0111\u00e1","ho\u1eb7c \u0111\u01b0\u1eddng xi m\u0103ng th\u00ec m\u1eb7t \u0111\u01b0\u1eddng s\u1ebd x\u1ea3y ra hi\u1ec7n t\u01b0\u1ee3ng l\u00f5m xu\u1ed1ng d\u01b0\u1edbi. D\u00f9ng ray th\u00e9p v\u00e0 t\u00e0 v\u1eb9t, tr\u1ecdng l\u1ef1c c\u1ee7a xe l\u1eeda \u0111\u01b0\u1ee3c d\u00e0n \u0111\u1ec1u n\u00ean c\u00f3 th\u1ec3 tr\u00e1nh \u0111\u01b0\u1ee3c t\u00ecnh tr\u1ea1ng \u0111\u00f3. Ngo\u00e0i ra, gi\u1eefa hai thanh ray c\u1ee7a \u0111\u01b0\u1eddng s\u1eaft c\u00f3 kho\u1ea3ng c\u00e1ch nh\u1ea5t \u0111\u1ecbnh, g\u1ecdi l\u00e0 chi\u1ec1u r\u1ed9ng \u0111\u01b0\u1eddng ray, n\u00f3 ph\u00f9 h\u1ee3p v\u1edbi khu v\u1ef1c c\u1ee7a hai b\u00e1nh xe c\u00f9ng tr\u1ee5c hai b\u00ean c\u00f3 g\u1edd. Nh\u01b0 v\u1eady, th\u00f4ng qua quan h\u1ec7 gi\u1eefa b\u00e1nh xe v\u00e0 \u0111\u01b0\u1eddng ray, xe l\u1eeda c\u00f3 th\u1ec3 ch\u1ea1y theo h\u01b0\u1edbng c\u1ee7a hai \u0111\u01b0\u1eddng ray. T\u1ea1i sao \u0111\u00e1 hoa l\u1ea1i c\u00f3 nhi\u1ec1u m\u00e0u? B\u1ea1n \u0111\u00e3 t\u1eebng \u0111\u1ebfn B\u1eafc Kinh ch\u01b0a? Khi b\u1ea1n \u0111i d\u1ea1o quanh \u0110\u1ea1i l\u1ec5 \u0111\u01b0\u1eddng nh\u00e2n d\u00e2n tr\u00ean qu\u1ea3ng tr\u01b0\u1eddng Thi\u00ean An M\u00f4n, \u0111\u1eadp v\u00e0o m\u1eaft tr\u01b0\u1edbc ti\u00ean l\u00e0 m\u1ed9t d\u00e3y c\u1ed9t m\u00e0u tr\u1eafng x\u00e1m to l\u1edbn v\u00e0 tr\u00f2n. B\u1ea1n c\u00f3 bi\u1ebft ch\u00fang \u0111\u01b0\u1ee3c l\u00e0m b\u1eb1ng g\u00ec kh\u00f4ng? Khi b\u1ea1n \u0111i g\u1ea9n \u0111\u1ebfn bia t\u01b0\u1edfng ni\u1ec7m c\u00e1c anh h\u00f9ng nh\u00e2n d\u00e2n, b\u1ea1n th\u1ea5y c\u1ed9t bia tr\u1eafng nh\u01b0 ng\u1ecdc, xung quanh kh\u1eafc ph\u00f9 \u0111i\u00eau kia th\u1eadt h\u00f9ng v\u0129 v\u00e0 trang nghi\u00eam bi\u1ebft bao. Th\u1ebf b\u1ea1n c\u00f3 bi\u1ebft ch\u00fang \u0111\u01b0\u1ee3c l\u00e0m b\u1eb1ng g\u00ec kh\u00f4ng? Th\u00ec ra, nh\u1eefng th\u1ee9 \u0111\u00e1 \u0111\u1eb9p kia \u0111\u1ec1u l\u00e0 \u0111\u00e1 hoa. Ch\u1ee7ng lo\u1ea1i \u0111\u00e1 hoa r\u1ea5t nhi\u1ec1u, nh\u1eefng c\u1ed9t \u0111\u00e1 h\u00e0nh lang m\u00e0u tr\u1eafng x\u00e1m kia g\u1ecdi l\u00e0 \u201cng\u1ea3i di\u1ec7p thanh\u201d; \u0111\u00e1 bia m\u00e0u tr\u1eafng tinh khi\u1ebft kh\u00f4ng t\u1ea1p ch\u1ea5t kia g\u1ecdi l\u00e0 \u201ch\u00e1n b\u1ea1ch ng\u1ecdc\u201d . Nh\u1eefng b\u1ee9c bi\u1ec3u ng\u1eef, c\u1ea9u \u0111\u00e1 tr\u1eafng tr\u01b0\u1edbc c\u1ed5ng Thi\u00ean An M\u00f4n c\u0169ng \u0111\u01b0\u1ee3c kh\u1eafc b\u1eb1ng h\u00e1n b\u1ea1ch ng\u1ecdc. \u0110\u00e1 hoa l\u00e0 m\u1ed9t lo\u1ea1i v\u1eadt li\u1ec7u x\u00e2y d\u1ef1ng r\u1ea5t qu\u00fd v\u00e0 n\u1ed5i ti\u1ebfng. Th\u00e0nh ph\u1ed1 \u0110\u1ea1i L\u00fd c\u1ee7a t\u1ec9nh V\u00e2n Nam s\u1ea3n xu\u1ea5t nhi\u1ec1u lo\u1ea1i \u0111\u00e1 n\u00e0y n\u00ean c\u00f3 t\u00ean l\u00e0 \u0111\u00e1 \u0110\u1ea1i L\u00fd (\u0111\u00e1 hoa). C\u00f3 \u0111i\u1ec1u, \u0111\u00e1 hoa kh\u00f4ng nh\u1ea5t thi\u1ebft ph\u1ea3i \u0111\u01b0\u1ee3c chuy\u1ec3n t\u1eeb \u0110\u1ea1i L\u00fd \u0111\u1ebfn, nh\u1eefng n\u01a1i kh\u00e1c c\u0169ng c\u00f3 \u0111\u00e1 hoa. Th\u00e0nh ph\u1ea9n ho\u00e1 h\u1ecdc c\u1ee7a \u0111\u00e1 hoa l\u00e0 Canxi cacbonat. Canxi cacbonat nguy\u00ean ch\u1ea5t c\u00f3 m\u00e0u tr\u1eafng, \u201ch\u00e1n b\u1ea1ch ng\u1ecdc\u201d ch\u00ednh l\u00e0 Canxi cacbonat nguy\u00ean ch\u1ea5t. Canxi cacbonat kh\u00f3 tan trong n\u01b0\u1edbc cho n\u00ean nh\u1eefng bi\u1ec3u ng\u1eef tr\u01b0\u1edbc Thi\u00ean An M\u00f4n b\u1ecb n\u01b0\u1edbc m\u01b0a h\u1eaft trong nhi\u1ec1u n\u0103m v\u1eabn \u0111\u1ee9ng s\u1eebng s\u1eefng m\u00e0 kh\u00f4ng sao. C\u00f3 \u0111i\u1ec1u, canxi cacbonat m\u1ed9t khi g\u1eb7p mu\u1ed1i axit l\u00e0 s\u1ebd l\u1eadp t\u1ee9c s\u00f9i b\u1ecdt kh\u00ed v\u00e0 th\u1ea3i ra c\u00e1cbonic, ch\u1ec9 l\u00e1t sau l\u00e0 b\u1ecb tan ra ngay. M\u1ecdi ng\u01b0\u1eddi th\u01b0\u1eddng d\u00f9ng c\u00e1ch n\u00e0y \u0111\u1ec3 ph\u00e2n bi\u1ec7t v\u1edbi \u0111\u00e1 hoa. \u0110\u00e1 hoa thi\u00ean nhi\u00ean th\u01b0\u1eddng kh\u00f4ng ph\u1ea3i l\u00e0 Canxi axit cacbon nguy\u00ean ch\u1ea5t, b\u00ean trong c\u00f3 nhi\u1ec1u t\u1ea1p ch\u1ea5t. Do t\u1ea1p ch\u1ea5t trong \u0111\u00f3 kh\u00e1c nhau n\u00ean m\u00e0u s\u1eafc c\u1ee7a \u0111\u00e1 hoa c\u01b0\u01a1ng c\u0169ng kh\u00e1c nhau. Ch\u00ednh v\u00ec nh\u01b0 v\u1eady n\u00ean ch\u1ee7ng lo\u1ea1i c\u1ee7a \u0111\u00e1 hoa r\u1ea5t nhi\u1ec1u, m\u00e0u s\u1eafc \u0111a d\u1ea1ng, phong ph\u00fa, v\u00ed d\u1ee5 nh\u01b0 \u201c\u0110\u00f4ng B\u1eafc h\u1ed3ng\u201d m\u00e0u \u0111\u1ecf, \u201cT\u1eed \u0111\u1eadu bi\u1ec7n\u201d m\u00e0u t\u00edm, \u201cH\u1ea3i \u0111\u00e0o\u201d (s\u00f3ng bi\u1ec3n) m\u00e0u \u0111en x\u00e1m... N\u00f3i chung, m\u00e0u \u0111\u1ecf l\u00e0 do b\u00ean trong ch\u1ee9a Coban, m\u00e0u xanh l\u00e0 do c\u00f3 ch\u1ee9a \u0111\u1ed3ng, c\u00f2n m\u00e0u \u0111en v\u00e0 m\u00e0u x\u00e1m l\u00e0 do ch\u1ee9a s\u1eaft. \u0110\u00e1 hoa m\u1ecbn, \u0111\u1ec1u, m\u00e0u s\u1eafc t\u01b0\u01a1i t\u1eafn, hoa v\u0103n \u0111\u1eb9p, l\u00e0 v\u1eadt li\u1ec7u x\u00e2y d\u1ef1ng r\u1ea5t t\u1ed1t. B\u00e2y gi\u1edd, r\u1ea5t nhi\u1ec1u ng\u01b0\u1eddi c\u00f2n th\u00edch d\u00f9ng \u0111\u00e1 hoa \u0111\u1ec3 trang tr\u00ed n\u1ed9i th\u1ea5t, v\u00ed d\u1ee5 nh\u01b0 l\u00e1t n\u1ec1n, l\u00e0m m\u1eb7t b\u00e0n, \u0111i\u00eau kh\u1eafc ngh\u1ec7 thu\u1eadt v\u00e0 d\u00f9ng l\u00e0m \u0111\u1ed3 trang s\u1ee9c. Cho d\u00f9 l\u00e0 d\u00f9ng nh\u01b0 th\u1ebf n\u00e0o th\u00ec \u0111\u00e1 hoa \u0111\u1ec1u t\u1ecf ra v\u00f4 c\u00f9ng sang tr\u1ecdng v\u00e0 \u0111\u1eb9p \u0111\u1ebd.","\u0110i\u1ec1u g\u00ec l\u00e0m thu\u1ef7 tinh trong su\u1ed1t? Ch\u00fang ta c\u00f3 th\u1ec3 nh\u00ecn qua h\u1ea9u h\u1ebft c\u00e1c ch\u1ea5t th\u1ec3 kh\u00ed v\u00e0 th\u1ec3 l\u1ecfng nh\u01b0 kh\u00f4ng kh\u00ed, n\u01b0\u1edbc, r\u01b0\u1ee3u, x\u0103ng d\u1ea9u... nh\u01b0ng kh\u00f3 nh\u00ecn th\u1ea5u qua nh\u1eefng ch\u1ea5t r\u1eafn nh\u01b0 s\u1eaft, \u0111\u1ed3ng, g\u1ed7. \u1ea4y v\u1eady m\u00e0 thu\u1ef7 tinh tuy c\u0169ng l\u00e0 ch\u1ea5t r\u1eafn, nh\u01b0ng l\u1ea1i trong su\u1ed1t, c\u00f3 th\u1ec3 nh\u00ecn qua \u0111\u01b0\u1ee3c. S\u1edf d\u0129 ch\u00fang ta nh\u00ecn \u0111\u01b0\u1ee3c qua ch\u1ea5t kh\u00ed v\u00e0 ch\u1ea5t l\u1ecfng v\u00ec c\u00e1c ph\u00e2n t\u1eed c\u1ee7a ch\u00fang s\u1eafp x\u1ebfp r\u1ea5t l\u1ecfng l\u1ebbo, s\u00f3ng \u00e1nh s\u00e1ng c\u00f3 th\u1ec3 d\u1ec5 d\u00e0ng l\u1ecdt qua. Ng\u01b0\u1ee3c l\u1ea1i, ph\u00e2n t\u1eed ch\u1ea5t r\u1eafn li\u00ean k\u1ebft v\u1edbi nhau theo tr\u1eadt t\u1ef1 d\u00e0y \u0111\u1eb7c, nh\u01b0 c\u00e1c vi\u00ean g\u1ea1ch x\u1ebfp x\u00edt l\u1ea1i v\u1edbi nhau th\u00e0nh c\u00e1c b\u1ee9c t\u01b0\u1eddng ch\u1eafn \u00e1nh s\u00e1ng. \u1ede nhi\u1ec7t \u0111\u1ed9 cao, thu\u1ef7 tinh tan ch\u1ea3y th\u00e0nh ch\u1ea5t l\u1ecfng. Khi \u0111\u00f3, c\u00e1c ph\u00e2n t\u1eed s\u1eafp x\u1ebfp r\u1ea5t ng\u1eabu nhi\u00ean, kh\u00f4ng theo m\u1ed9t tr\u1eadt t\u1ef1 n\u00e0o. Nh\u01b0ng v\u00ec thu\u1ef7 tinh \u0110\u00f4ng \u0111\u1eb7c r\u1ea5t nhanh, c\u00e1c ph\u00e2n t\u1eed v\u1eabn gi\u1eef nguy\u00ean \u1edf tr\u1ea1ng th\u00e1i h\u1ed7n lo\u1ea1n, n\u00ean khi \u0111\u00e3 \u1edf th\u1ec3 r\u1eafn, \u00e1nh s\u00e1ng v\u1eabn d\u1ec5 d\u00e0ng l\u1ecdt qua. T\u1ea1i sao nam ch\u00e2m m\u1ea5t d\u1ea7n t\u1eeb t\u00ednh? C\u00e1c nam ch\u00e2m th\u1ebf h\u1ec7 m\u1edbi \u0111\u01b0\u1ee3c l\u00e0m t\u1eeb nh\u1eefng v\u1eadt li\u1ec7u h\u1ea9u nh\u01b0 kh\u00f4ng l\u00e0m m\u1ea5t t\u1eeb t\u00ednh theo th\u1eddi gian nh\u01b0 c\u00e1c lo\u1ea1i nam ch\u00e2m h\u00ecnh ch\u1eef U tr\u01b0\u1edbc kia. Nam ch\u00e2m g\u1ed3m r\u1ea5t nhi\u1ec1u v\u00f9ng t\u1eeb t\u00ednh nh\u1ecf g\u1ecdi l\u00e0 mi\u1ec1n. T\u1eeb tr\u01b0\u1eddng c\u1ee7a nam ch\u00e2m \u0111i theo h\u01b0\u1edbng ng\u01b0\u1ee3c chi\u1ec1u v\u1edbi c\u00e1c mi\u1ec1n t\u1ea1o ra t\u1eeb tr\u01b0\u1eddng \u0111\u00f3. \u0110i\u1ec1u n\u00e0y c\u00f3 xu h\u01b0\u1edbng l\u00e0m c\u00e1c mi\u1ec1n quay ng\u01b0\u1ee3c chi\u1ec1u t\u1eeb tr\u01b0\u1eddng c\u1ee7a ch\u00fang l\u1ea1i. V\u1edbi nam ch\u00e2m hi\u1ec7n \u0111\u1ea1i, c\u00e1c mi\u1ec1n \u1edf m\u1ee9c \u0111\u1ed9 n\u00e0o \u0111\u00f3 b\u1ecb t\u00ea li\u1ec7t v\u1ec1 m\u1eb7t n\u0103ng l\u01b0\u1ee3ng, l\u00e0m ch\u00fang kh\u00f4ng d\u1ec5 b\u1ecb t\u00e1c \u0111\u1ed9ng b\u1edfi hi\u1ec7u \u1ee9ng tr\u00ean. C\u1ee5c nam ch\u00e2m ch\u1ec9 m\u1ea5t t\u1eeb t\u00ednh khi b\u1ecb \u0111un n\u00f3ng \u1edf nhi\u1ec7t \u0111\u1ed9 cao ho\u1eb7c b\u1ecb rung \u0111\u1ed9ng m\u1ea1nh. C\u00e1c nam ch\u00e2m ki\u1ec3u m\u1edbi s\u1eed d\u1ee5ng nh\u1eefng ch\u1ea5t li\u1ec7u nh\u01b0 alnico (h\u1ee3p ch\u1ea5t g\u1ed3m nh\u00f4m - nickel cobalt) v\u00e0 cobalt samarium c\u00f3c\u1ea5u tr\u00fac n\u1ed9i t\u1ea1i ng\u0103n ch\u1eb7n s\u1ef1 tho\u00e1i ho\u00e1 c\u1ee7a c\u00e1c m\u1ea1ch t\u1eeb. Ch\u00fang \u0111\u01b0\u1ee3c chia th\u00e0nh nhi\u1ec1u m\u1ea3nh v\u1ee5n nh\u1ecf, m\u1ed7i m\u1ea3nh l\u00e0 m\u1ed9t mi\u1ec1n. Ng\u01b0\u1ee3c l\u1ea1i, nam ch\u00e2m h\u00ecnh ch\u1eef U ki\u1ec3u c\u0169 c\u00f3 mi\u1ec1n l\u1edbn h\u01a1n r\u1ea5t nhi\u1ec1u, l\u00e0 nh\u1eefng m\u1ea9u s\u1eaft c\u1ee9ng v\u1edbi mi\u1ec1n \u0111\u01b0\u1ee3c bao b\u1ecdc b\u1edfi c\u00e1c t\u1ea1p ch\u1ea5t carbua s\u1eaft. M\u1ed9t \u0111i\u1ec1u t\u01b0\u1edfng nh\u01b0 ngh\u1ecbch l\u00fd \u1edf \u0111\u00e2y l\u00e0 nh\u1eefng m\u1ea3nh v\u1ee5n nh\u1ecf v\u1edbi k\u00edch th\u01b0\u1edbc t\u1ed1i \u01b0u l\u1ea1i c\u00f3 t\u00ednh n\u0103ng \u1ed5n \u0111\u1ecbnh h\u01a1n nh\u1eefng m\u1ea3nh l\u1edbn trong c\u00e1c ch\u1ea5t t\u1eeb t\u00ednh. Do v\u1eady, lo\u1ea1i nam ch\u00e2m ch\u1eef U k\u00e9m b\u1ec1n v\u1eefng h\u01a1n nhi\u1ec1u so v\u1edbi nam ch\u00e2m ki\u1ec3u m\u1edbi. C\u1ef1c quang l\u00e0 hi\u1ec7n t\u01b0\u1ee3ng nh\u01b0 th\u1ebf n\u00e0o? V\u00e0o nh\u1eefng \u0111\u00eam tr\u1eddi quang m\u00e2y t\u1ea1nh, tr\u00ean v\u00f9ng tr\u1eddi \u1edf hai c\u1ef1c Tr\u00e1i \u0111\u1ea5t th\u01b0\u1eddng li\u00ean ti\u1ebfp xu\u1ea5t hi\u1ec7n nh\u1eefng d\u1ea3i \u00e1nh s\u00e1ng m\u00e0u h\u1ed3ng, lam, v\u00e0ng, t\u00edm... r\u1ef1c r\u1ee1 v\u00e0 bi\u1ebfn \u1ea3o kh\u00f4n","l\u01b0\u1eddng. Tia n\u00e0y v\u1eeba t\u1eaft \u0111i, tia kh\u00e1c l\u1ea1i xu\u1ea5t hi\u1ec7n, nh\u1ea3y m\u00faa, lung tinh \u0111\u1ee7 m\u00e0u s\u1eafc. C\u00f3 l\u00fac ch\u00fang ch\u1ec9 l\u00e0 m\u1ed9t tia s\u00e1ng mong manh, c\u00f3 khi mang h\u00ecnh d\u1ebb qu\u1ea1t, h\u00ecnh ng\u1ecdn l\u1eeda, r\u1ed3i l\u1ea1i ho\u00e1 th\u00e0nh nh\u1eefng v\u00f2ng cung m\u00e0u l\u00e1 c\u00e2y v\u1eaft tr\u00ean n\u1ec1n tr\u1eddi. \u0110\u00f3 ch\u00ednh l\u00e0 c\u1ef1c quang. C\u1ef1c quang l\u00e0 m\u1ed9t hi\u1ec7n t\u01b0\u1ee3ng hi\u1ebfm th\u1ea5y \u1edf nhi\u1ec1u n\u01a1i tr\u00ean Tr\u00e1i \u0111\u1ea5t. Nh\u01b0ng \u1edf Alaska (M\u1ef9), ph\u1ea9n l\u1edbn l\u00e3nh th\u1ed5 Canada, hay v\u00f9ng n\u1eb1m t\u1eeb v\u0129 \u0111\u1ed9 60 tr\u1edf l\u00ean, \u0111\u00e2y l\u1ea1i l\u00e0 m\u1ed9t chuy\u1ec7n b\u00ecnh th\u01b0\u1eddng. C\u1ef1c quang th\u01b0\u1eddng xu\u1ea5t hi\u1ec7n v\u00e0o bu\u1ed5i \u0111\u00eam. C\u00f3 ng\u01b0\u1eddi y\u1ebfu b\u00f3ng v\u00eda, nh\u00ecn th\u1ea5y hi\u1ec7n t\u01b0\u1ee3ng n\u00e0y li\u1ec1n cho l\u00e0. ng\u00e0y t\u1eadn th\u1ebf s\u1eafp \u0111\u1ebfn. V\u00e0o nh\u1eefng n\u0103m 80 c\u1ee7a th\u1ebf k\u1ef7 XIX, ng\u01b0\u1eddi ta kh\u00e1m ph\u00e1 ra r\u1eb1ng t\u1eeb tr\u01b0\u1eddng c\u1ee7a Tr\u00e1i \u0111\u1ea5t c\u00f3 li\u00ean quan \u0111\u1ebfn hi\u1ec7n t\u01b0\u1ee3ng k\u1ef3 \u1ea3o n\u00e0y. Khi electronva v\u00e0o m\u1ed9t v\u1eadt th\u1ec3 n\u00e0o \u0111\u00f3, n\u00f3 c\u00f3 th\u1ec3 t\u1ea1o ra \u00e1nh s\u00e1ng (\u0111i\u1ec1u n\u00e0y c\u0169ng t\u01b0\u01a1ng t\u1ef1 nh\u01b0 nguy\u00ean l\u00fd ho\u1ea1t \u0111\u1ed9ng c\u1ee7a m\u00e0n h\u00ecnh tivi v\u00e0 m\u00e1y t\u00ednh). Nh\u01b0 v\u1eady, c\u00e1c nh\u00e0 khoa h\u1ecdc cho r\u1eb1ng c\u1ef1c quang c\u00f3 th\u1ec3 sinh ra khi c\u00e1c d\u00f2ng h\u1ea1t mang \u0111i\u1ec7n t\u00edch trong v\u0169 tr\u1ee5 va ch\u1ea1m v\u1edbi b\u1ea9u kh\u00ed quy\u1ec3n. K\u1ebft qu\u1ea3 nghi\u00ean c\u1ee9u khoa h\u1ecdc v\u00e0o c\u00e1c n\u0103m 1957 1958 cho r\u1eb1ng khi tr\u00ean M\u1eb7t tr\u1eddi xu\u1ea5t hi\u1ec7n c\u00e1c v\u1ebft \u0111en, gi\u00f3 M\u1eb7t tr\u1eddi t\u1ea1t v\u00e0o Tr\u00e1i \u0111\u1ea5t, mang theo m\u1ed9t d\u00f2ng h\u1ea1t n\u0103ng l\u01b0\u1ee3ng cao g\u00e2y ra hi\u1ec7n t\u01b0\u1ee3ng c\u1ef1c quang. C\u00e1c electron v\u00e0 protontrong d\u00f2ng h\u1ea1t n\u00e0y \u0111i v\u00e0o b\u1ea9u kh\u00ed quy\u1ec3n. D\u01b0\u1edbi \u1ea3nh h\u01b0\u1edfng c\u1ee7a \u0111\u1ecba t\u1eeb, ch\u00fang b\u1ecb h\u00fat v\u1ec1 hai c\u1ef1c Tr\u00e1i \u0111\u1ea5t. T\u1ea1i \u0111\u00e2y, ch\u00fang va ch\u1ea1m v\u00e0 k\u00edch th\u00edch c\u00e1c ph\u1ea9n t\u1eed kh\u00ed, l\u00e0m c\u00e1c ph\u00e2n t\u1eed n\u00e0y ph\u00e1t ra b\u1ee9c x\u1ea1 \u0111i\u1ec7n t\u1eeb d\u01b0\u1edbi d\u1ea1ng \u00e1nh s\u00e1ng nh\u00ecn th\u1ea5y. B\u1ea9u kh\u00ed quy\u1ec3n c\u00f3 r\u1ea5t nhi\u1ec1u ch\u1ea5t nh\u01b0 oxy, nito, heli, hydro, neon... D\u01b0\u1edbi t\u00e1c \u0111\u1ed9ng c\u1ee7a d\u00f2ng h\u1ea1t mang \u0111i\u1ec7n, \u00e1nh s\u00e1ng do c\u00e1c ch\u1ea5t kh\u00ed kh\u00e1c nhau t\u1ea1o ra c\u0169ng kh\u00e1c nhau, v\u00ec th\u1ebf c\u1ef1c quang c\u00f3 mu\u00f4n m\u00e0u ng\u00e0n s\u1eafc. C\u1ef1c quang khi s\u1ebd xu\u1ea5t hi\u1ec7n m\u1ea1nh th\u01b0\u1eddng \u0111i k\u00e8m v\u1edbi nh\u1eefng thay \u0111\u1ed5i trong \u0111\u1ecba t\u1eeb v\u00e0 k\u00e9o theo s\u1ef1 giao thoa v\u1edbi s\u00f3ng v\u00f4 tuy\u1ebfn, s\u00f3ng \u0111i\u1ec7n tho\u1ea1i. Th\u1eddi k\u1ef3 m\u1ea1nh, y\u1ebfu c\u1ee7a c\u1ef1c quang c\u00f3 m\u1ed1i li\u00ean quan ch\u1eb7t ch\u1ebd t\u1edbi chu k\u1ef3 ho\u1ea1t \u0111\u1ed9ng c\u1ee7a M\u1eb7t tr\u1eddi. Khi M\u1eb7t tr\u1eddi \u1edf \u0111\u1ec9nh chu k\u1ef3, (ho\u1ea1t \u0111\u1ed9ng m\u1ea1nh nh\u1ea5t), n\u00f3 s\u1ebd b\u1ee9c x\u1ea1 nhi\u1ec1u h\u01a1n m\u1ee9c b\u00ecnh th\u01b0\u1eddng. L\u00fac n\u00e0y d\u00f2ng h\u1ea1t mang \u0111i\u1ec7n va ch\u1ea1m nhi\u1ec1u h\u01a1n v\u1edbi kh\u00ed quy\u1ec3n, do \u0111\u00f3, c\u1ef1c quang s\u1ebd xu\u1ea5t hi\u1ec7n r\u1ea5t nhi\u1ec1u v\u00e0 k\u1ef3 v\u0129. Kim lo\u1ea1i c\u00f3 th\u1ec3 t\u1ef1 b\u1ed1c ch\u00e1y? N\u1ebfu r\u1ea3i lo\u1ea1i b\u1ed9t ch\u00ec \u0111en m\u1ecbn l\u00ean m\u1ed9t t\u1edd gi\u1ea5y \u0111\u1eb7t trong b\u00f3ng t\u1ed1i, b\u1ea1n s\u1ebd th\u1ea5y nh\u1eefng ch\u1ea5m l\u1eeda l\u1ed1m \u0111\u1ed1m. N\u1ebfu g\u1eb7p th\u1eddi ti\u1ebft kh\u00f4 hanh, \u0111\u00e1m b\u1ed9t ch\u00ec \u0111\u00f3 s\u1ebd c\u00f3 th\u1ec3 b\u00f9ng ch\u00e1y. Kim lo\u1ea1i m\u00e0 c\u0169ng ch\u00e1y \u01b0, sao l\u1ea1i th\u1ebf nh\u1ec9? Nh\u01b0 ch\u00fang ta \u0111\u00e3 bi\u1ebft, kim lo\u1ea1i ph\u1ea3n \u1ee9ng v\u1edbi oxy \u1edf kh\u00f4ng kh\u00ed. Th\u00f4ng th\u01b0\u1eddng, ph\u1ea3n \u1ee9ng oxy ho\u00e1 x\u1ea3y ra t\u01b0\u01a1ng \u0111\u1ed1i ch\u1eadm. \u0110\u00e2y l\u00e0 ph\u1ea3n \u1ee9ng sinh nhi\u1ec7t. Nhi\u1ec7t l\u01b0\u1ee3ng sinh ra t\u00edch t\u1ee5 d\u1ea9n d\u1ea9n \u1edf b\u1ec1 m\u1eb7t kim lo\u1ea1i khi\u1ebfn nhi\u1ec7t \u0111\u1ed9 t\u0103ng l\u00ean. Khi ta gom c\u00e1c h\u1ea1t kim lo\u1ea1i c\u1ef1c m\u1ecbn l\u1ea1i th\u00e0nh m\u1ed9t \u0111\u1ed1ng, di\u1ec7n t\u00edch ti\u1ebfp x\u00fac c\u1ee7a c\u00e1c h\u1ea1t v\u1edbi oxy trong"]