The Ultimate Guide to Almost Everything

["how was the first chocolate chip cookie created? In 1938, Ruth Wake\ufb01eld, innkeeper at the Toll House Inn, added small chunks of chocolate to plain cookie dough. She was surprised that the little chunks melted but stayed crunchy. The cookies were a hit, and the chocolate chip cookie\u2014also known as the Toll House cookie\u2014was born. Along with sports helmets, Kevlar is used in construction, spacecraft and law enforcement. People who clear away dangerous mines are protected by Kevlar suits. Kevlar has also been used as a component of prosthetic limbs. Kevlar","INVENTIONS howdid broken china lead to the dishwasher? J osephine Garis Cochran loved throwing dinner parties, but it upset her when her fancy plates got chipped while being washed and dried. She decided to invent a machine that would do the job faster and more safely. She worked in a shed behind her home in Illinois and patented her invention in 1886. In the 1880s, women were not taken seriously as inventors, so she used her initials when \ufb01ling for a patent. U.S. Patent number 355,139 was issued to J.G. Cochran. Then she started her own company to manufacture her invention. At the 1893 World\u2019s Fair, her dishwashers were used in the restaurants, and she won the highest prize for \u201cbest mechanical construction, durability and adaptation to its line of work\u201d at the event. Cochran was inducted into the National Inventors Hall of Fame in 2006, more than 100 years after her invention changed so many people\u2019s lives. what were Stethoscope Pacemaker some great inventions (used to listen (used to keep in medicine? to a person\u2019s the heart beating heart and lungs): in a regular 52 P O PU L AR SC I E N C E K I DS Ren\u00e9 Laennec, rhythm): Mark France, 1816 Lidwill and Edgar Booth, Australia, 1926","Chicago World\u2019s Fair, 1893 Dishwashing Machine, 1926 Blood Banks Arti\ufb01cial CT Scanning Laser Eye Heart (to ensure (computerized Surgery Tool blood is (used when 3D images of (used to remove available someone is tissue inside the cataracts): when needed): awaiting a heart body): Godfrey Patricia Bath, Charles Drew, transplant): Houns\ufb01eld, Great America, 1986 America, 1941 Domingo Liotta, Britain, 1972 Argentina, 1969 53","INVENTIONS What are these people doing? Falling, of course. But they\u2019re how doing it with style. In group did a parachuting events, large groups daredevil of people \ufb02y together and form shapes by holding one another\u2019s give arms or legs. They hold the shape skydivers for a few seconds, then release and separate before safely a soft \ufb02oating down. landing? W hat goes up must come down. But if you\u2019re coming down without an aircraft, you need a parachute. And a parachute needs a rip cord, the device that springs the chute from a backpack. Every soft landing today is thanks to Georgia Ann Broadwick. She was already a well-known parachutist in the early days of \ufb02ying. Back then, the parachutes opened with a string attached to an airplane or a balloon. On a 1914 jump, Broadwick\u2019s string got tangled. She dangled from the airplane for a moment, then cut the string. What happened next changed aviation history. As she fell, she \ufb01gured out how to pull the string that opened the chute herself. The rip cord was born, and parachuting soared. 54 POPUL AR SCIENCE KIDS","The world record for the most people in a skydiving group is 400, and it was set by a (large!) team of Thai military parachutists in 2006. The team needed \ufb01ve huge cargo planes to carry all the participants to the jump point. Broadwick\u2019s chutes were How do parachutists mostly made of silk. land? Once the Today\u2019s lighter, smaller parachute opens, it slows parachutes are made of the descent. Experts can durable, tough rip-stop slow themselves enough nylon. There are two types to basically land with of parachutes. One is the a light jog. Otherwise, classic teardrop shape\u2014a doing a forward roll as large half sphere above you land is the safe way long ropes. Most modern to get back to Earth. jumpers use a rectangular chute called a parafoil. This parachute gives the jumper more ways to control their direction and speed.","INVENTIONS Levitation what In movies like Star will the Wars and Back to the future bring? Future II, characters ride in machines that I nventors are always thinking about the seem to \ufb02oat over the future\u2014what\u2019s the next thing? Some ground, in a process inventions have long been dreamed called levitation. Using of; some are coming close to becoming jet engines, some reality, such as passenger planes that \ufb02y machines can do that without a pilot. Drones are already used today, but the engines in the military and in lots of scienti\ufb01c are enormous. No one projects. There are no people on these has \ufb01gured out how to \ufb02ying machines\u2014yet. Driverless cars are have smaller devices, already seen around the world\u2014will pilot- like skateboards, hover. free planes be next? Here are some other But the work continues, inventions that we can look forward to. so we may see this come to life soon! Holodecks Some well-known sci-\ufb01 TV shows feature the use of holograms to create alternate realities. Will they ever be real? Virtual reality (VR) goggles are a \ufb01rst step. They immerse a person in a projected digital world. Some devices also have gloves or other gear that help the viewer connect with what they see. Might a Star Trek-inspired holodeck be next?","Arti\ufb01cial Body Parts The use of prosthetics, such as arti\ufb01cial arms and legs, to replace body parts is already available in medicine. With the use of 3D printers, some scientists are going even further\u2014experimenting with printing organs, such as the kidney or pancreas. Others are looking at printing prosthetic ears. In 2013, a baby\u2019s life was saved with a tiny 3D-printed object that replaced a missing part of the baby\u2019s throat, allowing the infant to breathe safely. Perhaps one day, you\u2019ll order new body parts online. Time Travel Science \ufb01ction has long sent people zipping back and forth in time. Will it ever happen in reality? Science today shows that it is theoretically possible, though not for more than a few seconds\u2014and certainly not in a machine you can ride in. But as space travel expands farther into the galaxy, future astronauts may experience small time shifts as they speed away from Earth. 57","INVENTIONS who gave us emojis? when did Abbreviations like LOL were part of text phones get messaging from the start. Another way to save \u201csmart\u201d? space was emoticons, like :), which use standard keyboard characters. In 1999, a Japanese Inventors had been trying to artist took the idea one colorful, creative step create mobile phones almost further. Shigetaka Kurita designed a set of 176 since telephones were invented. tiny images that stand for words or emotions. It was not until the 1960s that He called them emojis. His original work is in actual devices could be carried the Museum of Modern Art in New York City. around to make calls\u2014but the Kurita\u2019s creations set off a worldwide craze that \ufb01rst model was the size of a brick. continues today. How popular are they? Emojis In the 1990s, smaller phones have even starred in their own movie! could make calls and send short texts, but they did not connect to who showed the internet. IBM\u2019s Simon (1992) computers how to was a big step forward; it was identify humans? able to make calls and send faxes and emails. However, Apple\u2019s CAPTCHA was created by an inventor from iPhone (2007) is considered the Guatemala named Luis von Ahn. CAPTCHA is not \ufb01rst \u201csmart\u201d phone, able to make just a funny way of saying \u201ccapture\u201d; it actually calls, send texts and surf the web. stands for something. Von Ahn honored 58 POPUL AR SCIENCE KIDS an early computer pioneer, Alan Turing, by calling his invention Completely Automated Public Turing test to tell Computers and Humans Apart.","who should why should we we thank for salute Grace color TV? Hopper? Believe it or not, your grandparents Everyone who clicks on a computer probably never watched TV in color should be thanking Admiral Grace while growing up. All the shows were Hopper, a digital pioneer who did most in black and white (the shows, not of her work while serving in the U.S. the actual people). Everyone wanted Navy. A mathematician, she joined the color TV, but it was not possible Navy during World War II. For the next until Mexican engineer Guillermo 50 years, she was at the forefront of Gonz\u00e1lez Camarena patented developments in computers, from writing a three-color system in 1942. He new programming languages to helping invented several other TV systems as design new and faster machines. One of well, and his ideas helped turn what the most famous was UNIVAC, considered we watch into living color. one of the key steps in modern computing. who thought up yellow traffic lights? Stop-and-go traf\ufb01c lights were around for decades before someone thought of adding the yellow \u201ccaution\u201d light. Garrett Morgan dreamed up this super-helpful safety idea and patented it in 1923. The \ufb01rst yellow lights were added on the streets of Cleveland, Ohio, where he lived, but the idea soon spread around the world.","CHAPTER 4 SPORTS Welcome to the wonderful and sometimes weird world of sports\u2014a place where anything can, and often does, happen. Sports can be played by individuals or teams, for points or for fun, by amateurs or professionals. Some sports are played with rules, referees and professional organizations. Sometimes they are more casual, like a pickup basketball or street hockey game. Sports are fun to play and exciting to watch. They are often unpredictable and astonishing. That\u2019s because the forces of physics and the rules of geometry are also at play in sports. So are the abilities and limits of the human body. Whether a soccer ball goes in the net or bounces off the crossbar, whether an athlete has enough lung and muscle power to keep going\u2014that\u2019s also part of the game.","Some adventurers get their thrills with wingsuits. Jumping from heights or from planes, they use \ufb02aps of fabric between their arms and legs to glide through the air in this thrilling sport. They still need parachutes to make a \ufb01nal landing, but on the ride down they are \ufb02ying much like a bird. In bubble soccer (or football, in the U.K.), players wear giant in\ufb02atable balls over the upper part of the body. They bump into one another and fall down often, but they\u2019re protected by the big bubbles.","SPORTS how hard is it to hit a baseball? V ery, very hard\u2014especially in the pros. The average fastball in the major leagues is thrown at more than 90 mph (145\u00a0kph) and travels about 60 feet (18 m). This means that the batter has about 150 milliseconds to decide whether to swing at the ball. Blink your eyes\u2014it\u2019s that quick. But it\u2019s even harder than that, because the ball is only in the right spot to be hit by the bat for less than 10 milliseconds. is there a Green why do Monster in Boston? today\u2019s players go Yes, and it eats up baseballs! The 37-foot (11-m) to WAR? left-\ufb01eld fence at Fenway Park, home of the Boston Red Sox, is one of baseball\u2019s most famous sights. Baseball is a game that\u2019s The huge wall has been part of the ballpark since measured in a dizzying array of it was built in 1912. The team\u2019s owner at the time statistics. One of the newest is didn\u2019t want people in the buildings beyond left WAR\u2014Wins Above Replacement. \ufb01eld to get a free view. So he built the wall about Using a complicated formula 25 feet (7.6 m) tall. Over time, it grew taller as the that is adjusted for what surrounding buildings did, and it was painted its position a person plays, WAR famous green shade starting in 1947. Today, fans shows how many more wins can sit in seats atop the Green Monster for one of a player is worth to his team baseball\u2019s most interesting views. than the average player would contribute. The number takes into account all the aspects of a player\u2019s performance, not just their hitting or base running or \ufb01elding skills. It\u2019s useful as a way of comparing the impact of players at different positions, on different teams and even in different eras. The highest single- season WAR value for any player was 15, for Babe Ruth, in 1923. 62 P O PU L AR SC I E N C E K I DS","does a 5 curveball really curve? TOP STRIKEOUT PITCHERS Yes, it does! The path it travels follows a downward curve. The Rank Player Strikeouts pitcher makes the ball spin by twisting his wrist as he releases the pitch. The 1 Nolan Ryan 5,714 spinning motion creates greater air pressure on top of the ball. That forces the ball to drop down at the 2 Randy Johnson 4,875 last moment\u2014a movement called breaking. It works because the batter (usually) doesn\u2019t realize that it\u2019s 3 Roger Clemens 4,672 a curveball until it\u2019s too low to hit. 4 Steve Carlton 4,136 how fast was the fastest Major 5 Bert Blyleven 3,701 League Baseball pitch ever thrown? *as of 2022 baseball season Pitching for the Cincinnati Reds on Sept.\u00a024, 2010, what\u2019s the Aroldis Chapman threw the fastest recorded longest hitting pitch\u2014measured at 105.1 mph (169.1\u00a0kph)\u2014in streak in Major League Baseball (MLB) history. (To professional compare, the average speed at a NASCAR race baseball? is 200\u00a0mph\/322 kph.) But today it would be in the record books as 105.8 mph (170.2 kph). Why Joe DiMaggio, the center \ufb01elder for the difference? It depends on where you look at the New York Yankees, had a hit in the ball. A baseball travels the fastest right when 56 games in a row. His amazing run it leaves the pitcher\u2019s hand. After that, resistance lasted from May 15 to July 16, 1941. from air slows it down. So, for example, a pitch He smashed the previous record that leaves a pitcher\u2019s hand at 100 mph (161 of 45 games, which was kph) could be measured at 99 mph (159 kph) at set by Willie Keeler 50 feet (15 m) from home plate; 94 mph (151 kph) in 1897. Since halfway to the batter; and 91 mph (146 kph) DiMaggio, the when it reaches home plate, which is about 60 closest anyone feet (18 m) away. The system MLB used in 2010, has come when Chapman threw his scorcher, measured was Pete pitches at roughly 10 feet (3 m) after they left the Rose, who pitcher\u2019s hand. Today velocity is measured right hit in 44 as the pitch is released. games in a row in 1978.","SPORTS what are some memorable mistakes in sports? O ne of the most shortsighted moves in sports happened in 1920, when Boston Red Sox owner Harry Frazee needed cash to fund a Broadway musical. He sold the contract of one of his best players, a young slugger and pitcher named George Herman \u201cBabe\u201d Ruth, to the New York Yankees for $125,000. The musical was only a moderate success, but Ruth became one of the best players in baseball history. The Red Sox went 85 years between World Series victories, suffering \u201cThe Curse of the Bambino.\u201d Ruth helped the Yankees win four World Series, and the stadium is still called \u201cThe House That Ruth Built.\u201d has a figure skater ever fallen off the ice? Figure skaters are used to falling on the ice while attempting dif\ufb01cult jumps during practice and competitions. But they don\u2019t usually fall off the ice. At the World Figure Skating Championships in 1991, Midori Ito mistimed a jump and started it too close to the edge of the rink. Her skate caught an open spot in the boards that surround the rink, and she tumbled off the ice. She was back on it a few seconds later and completed her routine. Considered one of the world\u2019s best female \ufb01gure skaters, Ito went on to win a silver medal at the Olympics the following year. why shouldn\u2019t you celebrate before you\u2019ve won? At the 2006 Winter Olympics in Turin, Italy, American Lindsey Jacobellis had a 50-yard (46-m) lead in snowboardcross and looked to be headed for an easy gold medal. She was having so much fun that on the \ufb01nal jump, she decided to celebrate with a fancy grab of her board. But she held on too long, fell and watched Tanja Frieden of Switzerland go past her. She ended up with a silver medal. 64 POPULAR SCIENCE KIDS","who helped the wrong team score? Jim Marshall was one of the best defensive ends in football, a towering giant of a man who played for the Minnesota Vikings from 1961 to 1979. On Oct. 25, 1964, with the Vikings leading the San Francisco 49ers 27\u201317, Marshall scooped up a fumble and ran toward the wrong end zone. \u201cWrong Way Marshall\u201d went down in football infamy. The 49ers scored a 2-point safety on the bonehead play\u2014 although they still lost the game. what role did a marching band play in a football loss? On Nov.\u00a020,\u00a01982, the University of California Golden Bears football team scored a dramatic last-second victory over the Stanford Cardinals. The Cardinals had seemed like sure winners up to that point, and the Stanford band mistakenly thought the game was over. They came onto the \ufb01eld, and a California player tripped over a trombonist while scoring the winning touchdown\u2014an event that became known as \u201cThe Play.\u201d","SPORTS who was the \ufb01rst woman to climb Mount Everest? J unko Tabei (below), a Japanese mountaineer, scaled the world\u2019s tallest mountain in 1975, reaching the summit on May 16. She was co-leader of a 15-person, all-female climbing party called the Japanese Women\u2019s Everest Expedition. Buried by an avalanche and knocked unconscious on the way up, Tabei persevered and completed the climb of 29,029 feet (8,848 m). She was 35 when she climbed Everest, but she \ufb01rst fell in love with mountain climbing at age 10 on a school \ufb01eld trip. During her lifetime, Tabei became the \ufb01rst woman to climb the Seven Summits, the highest mountains on every continent. you don\u2019t say! Mount Everest is one of the peaks known as the Seven Summits, the highest mountains on each continent. The others are: Mount Kilimanjaro, in Africa; Mount Aconcagua, in South America; Denali, in North America; Mount Elbrus, in Europe; Mount Vinson, in Antarctica; and Puncak Jaya, in Oceania (the South Paci\ufb01c).","3 COOL FACTS YOU MAY NOT KNOW ABOUT MOUNTAIN CLIMBING 1\/ Mountaineering requires special clothing designed to keep you warm and dry in extreme cold and wind. To save money, Junko Tabei and her team made some of their own gear. They made gloves and waterproof pouches that were sewn from recycled car seats as well as special pants made from old curtains. 2\/ Our bodies aren\u2019t adapted to the frigid temperatures, swirling winds and limited oxygen at high altitudes. A series of base camps lets climbers adjust as they climb in stages. 3\/ Communication is essential in order to monitor progress during a climb, stay informed about weather risks and coordinate activities with multiple climbing groups that are on a peak at the same time. Smaller, lighter-weight electronics, satellite radio improvements, and high-altitude weather stations are some of the high-tech tools that make mountaineering safer for both climbers and guides. 67","SPORTS what T he \ufb01rst modern Olympics were held makes the in 1896 in Athens, Greece. Since Olympics then, they\u2019ve produced a huge number so special? of amazing moments of triumph, failure, heartbreak, grit and determination, at both the Summer Games and the Winter Games. The athletes, their stories and their accomplishments are a shared experience of human effort and achievement. which athlete gave who holds the up a chance at a record for medal to save the fastest a competitor? marathon without Canadian sailor shoes? Lawrence Lemieux was in medal contention Abebe Bikila of at the 1988 Olympics in Seoul, South Korea. The race Ethiopia won the was held despite the dangerous winds and high seas. About halfway marathon at the 1960 through, he noticed that a competitor\u2019s boat had capsized and saw only one of Rome Olympics, with its two sailors. He abandoned the race to \ufb01nd the missing sailor and then went a record time of 2 hours, 15 back to help its captain. Lemieux said later he had absolutely no regrets. minutes and 16.2 seconds. Bikila had intended to wear running shoes, but the shoes he\u2019d bought for the race gave him blisters. He ran barefoot for 26.2 miles (42.2 km), a Guinness World Record for the fastest marathon run barefoot. what was a most unexpected Winter Olympics surprise? The Jamaican bobsled team competed at the 1988 Winter Games in Calgary, Canada, inspiring the world. They \ufb01nished in 30th place overall, but just qualifying was a major accomplishment for a team that had trained on a concrete track in a country without snow. 68 POPUL AR SCIENCE KIDS","what was the Miracle on Ice? At the 1980 Winter Olympics in Lake Placid, New York, a group of American college players beat the Soviets\u2014considered the world\u2019s best ice hockey team\u2014and went on to win the gold. The improbable U.S. victory was called the Miracle on Ice and is celebrated as one of the greatest moments in 20th-century sports. what is the Korbut Flip, and why was it banned? Olga Korbut, a 17-year-old Soviet gymnast, brought renewed attention to the sport during the 1972 Olympics when she introduced a move that left people amazed. Performing on the uneven bars, Korbut stood on the top bar, did a 360-degree back\ufb02ip in midair, then grabbed onto the bar and continued to swing down to the lower bar. Technically called a swingdown, this move is known as the Korbut Flip. Deemed too risky and dangerous, the Olympics banned its use. Korbut won three gold medals and one silver medal at the 1972 games plus another gold and silver at the 1976 Olympics. who has won the most Olympic medals? As a child, Michael Phelps found it hard to focus. He couldn\u2019t sit still. Doctors diagnosed him with ADHD, or attention-de\ufb01cit\/hyperactivity disorder. Swimming, along with medication, allowed Phelps to concentrate. And that changed his life. Phelps was just 16 at his \ufb01rst Olympics, and the fact that he didn\u2019t win a medal pushed him to train harder and be more focused. Over the next four Olympics, Phelps won a record-breaking 23 gold, three silver, and two bronze medals.","SPORTS what W hether it\u2019s water are the most polo, Marco Polo extreme or just splashing around, water sports? playing in the water can be lots of fun. But some people take water sports to the extreme, whether they are on top of the water or down deep. There are thrills, chills and risks involved\u2014don\u2019t try these at home! when are shoulder pads a no-no in football? Take a deep breath before jumping in for underwater football, where the goal is to move a weighted ball to the other end of a pool while the opposing team tries to stop you. Equipment includes masks, snorkels and swim \ufb01ns. The sport was invented in the 1960s in Manitoba, Canada, where outdoor temperatures can reach a bracing -1.3\u00b0F (-18.5\u00b0C). what is underwater wrestling? In aquathlon (underwater wrestling), swimmers wearing masks and \ufb01ns wrestle each other in a pool. The aim is to remove a ribbon attached to the other person\u2019s ankle band. what is big-wave sur\ufb01ng? In big-wave sur\ufb01ng, the waves have to be at least 20 feet (6.1 m) high. Maya Gabeira (at left in 2021) holds the world record for highest wave ever surfed by a woman and the highest wave surfed by anyone in 2020. She set the record by sur\ufb01ng a 73.5-foot (22.4-m) wave near Nazar\u00e9, Portugal.","can people \ufb01sh with bows and arrows? Yes! It\u2019s a sport called aerial bow\ufb01shing. Fishermen ride in fast-moving boats and aim their bows and arrows at \ufb01sh that leap out of the water. The arrow is fastened to a reel that is screwed onto the side of the bow. who jumped off the highest cliff? Legend has it the sport of cliff diving dates back to 1770, when Hawaii\u2019s King Kahekili dove from a 63-foot (19-m) cliff into the sea. The current record holder in what is now a competitive sport is Lazaro \u201cLaso\u201d Schaller (above). He jumped off a board constructed atop a high cliff\u2014a safety precaution to ensure he cleared its rocky edge\u2014 diving 192 feet, 10 inches (58.8 m) into the water below. That\u2019s about as high as a 17-story building! what is underwater hockey? Fans and players of underwater hockey, played competitively in more than 40 countries, are hoping it will become an Olympic sport. To play, it helps to be a strong swimmer\u2014and to be able to hold your breath for long stretches. Equipment includes a diving mask, \ufb01ns, a snorkel and a glove (to protect the stick-holding hand from scrapes on the pool bottom). 71","SPORTS what is I t\u2019s no secret that sporting competitions can stretch the body to its limits. From speed skating to running, many sports an endurance tax the body, mind and spirit of the athlete who competes. sport? Some sports test human endurance beyond all others. what is the most dangerous race? The Dakar Rally is an on- and off-road race that takes place over 10 to 15 days. It\u2019s open to professional and amateur drivers, in different classes of vehicles\u2014from motorcycles to SUVs to trucks. The 2021 race covered 4,751 miles (7,646 km), in 12 stages. Called the most dif\ufb01cult and dangerous road race in the world, it\u2019s often held on extreme terrain, including Middle Eastern deserts and the mountains of South America. In such harsh conditions, crashes are inevitable\u2014 and dozens of competitors, spectators and of\ufb01cials have lost their lives. which skydiver broke the sound barrier? On Oct. 14, 2012, Austrian Felix Baumgartner stepped off the platform of a high-altitude balloon that hovered 128,100 feet (24\u00a0miles\/39\u00a0km) above Earth, eventually falling at around 833.9 miles an hour (1,342 kph), breaking the sound barrier. Baumgartner spent about 4 minutes, 20 seconds free- falling before engaging his parachute and landing safely. In total, his plummet to Earth took just 9 minutes, 3 seconds.","where is the coolest race? The Ice Marathon is like any other\u2014it covers a distance of 26.2 miles (42.1 km). What\u2019s different is that it\u2019s held on the frigid continent of Antarctica. Runners race across a course of snow and ice in an average wind chill temperature of -4\u00b0F (-20\u00b0C), with frequently gusting winds. Enduring such challenging conditions means that runners don\u2019t make their fastest race times\u2014the aim is to dress warmly enough and \ufb01nish the race. why would you run around the block 5,000 times? Runners must cover 3,100 miles (4,989 km), making the Sri Chinmoy Self-Transcendence 3,100 Mile Race the longest endurance footrace in the world. To complete the race within 52 days, participants run an average of more than two marathons a day. Sri Chinmoy was a spiritual leader who wanted to create an opportunity for runners to push beyond their limits. The runners race around the same city block in Queens, New York, more than 5,000 times. how long does it take to swim how far can a car across the English Channel? go in 24 hours? If you\u2019re Lynne Cox, just 9 hours, 36 minutes for Teams of three drivers take turns the 21-mile (34-km) swim. Cox set the world driving elite sports cars as fast as record in 1973, when she was 16 years old. they can at 24 Hours of Le Mans, (Australia\u2019s Trent Grimsey set the current world a nearly 100-year-old endurance record of 6 hours, 55 minutes in 2012.) Cox was race in Le Mans, France. The course the best long-distance cold water swimmer in is made up of closed public roads history. In 1987, she became the \ufb01rst person to and racing tracks. Whichever team swim across the Bering Strait\u2019s 2.7 miles (4.3\u00a0km). goes the farthest in 24 hours wins. The record for the longest distance is 5,410.713 km (about 3,362 miles), in 2010. The race began in 1923 as a way for carmakers to showcase the toughness of their vehicles.","SPORTS S occer, rugby and American football are all known as football. How are they alike, and in what ways are they different? All three sports have a lot in common\u2014starting with the fact that feet are involved at least some of the time. But they are also different in dozens of ways. All three are played on rectangular \ufb01elds, although the dimensions are different. Each is played with a ball that players must control to score. Soccer and American football have 11 players on the \ufb01eld at once, while rugby (also known as rugby football) has 15. American football players are clad in protective gear from head to foot, but soccer and rugby players wear no protection. The most common element of all, though, is that soccer, football and rugby fans are intense in their love for their sport and their teams. 4 QUICK FACTS ABOUT SOCCER, AMERICAN FOOTBALL AND RUGBY 1\/ A standard soccer ball has 32 panels\u201420 hexagons and 12 pentagons. 2\/ The \ufb01rst soccer nets were wicker baskets. 3\/ Rugby players have to pass the ball backward to their teammates. 4\/ The highest score total in a soccer game was 149\u20130. It occurred in 2002, when a team in Madagascar scored goal after goal into its own net, to protest an earlier penalty. 74 P O PU L AR SC I E N C E K I DS","how do you score points? what size and shape Soccer Knock the ball into are the balls? the opponent\u2019s goal net (called a goal), using any Soccer Round, body part other than your with a diameter hands and arms. of 8.66 inches (22 cm) and a American Football Carry circumference of or catch the ball behind 27 to 28 inches the opponent\u2019s goal line (68 to 70 cm) (touchdown) or kick the ball through the goal posts American (called a \ufb01eld goal). Football Oval, about 10.5 to 11.5 Rugby Carry the ball behind inches (26.7 to the opponent\u2019s touch line and 29.2 cm) long, with put it down on the ground a circumference (try), or drop the ball, let it hit at its widest the ground, and then kick it point of about 28 through the goal posts (called inches (71 cm) a penalty kick or drop goal). how big are the \ufb01elds? Soccer American Rugby 109 yards Rugby Oval, 110 to 120 yards Football (100 m) long, 76.5 about 10.6 inches (100 to 110 m) 100 yards (91.44 yards (70 m) wide\u2014 (27 cm) long, with long, 70 to 80 m) long between depending on a circumference yards (64 the goal lines, 160 league rules and at its widest point to 73 m) wide feet (48.8 m) wide type of competition of 24 inches (60 cm), depending on league rules and type of competition","SPORTS how can a person climb up falling water? W hen it\u2019s warm out, they can\u2019t! But when a waterfall freezes, climbers get out their gear and make their ascent. Ice climbing is dif\ufb01cult to master and requires special training and gear. There are two main types of ice climbs: alpine and water. Alpine ice climbs involve scaling steep sheets of ice. Water ice climbs requires ascending frozen waterfalls, which climbers consider more technically challenging than alpine ice climbing. how fast can a professional ice hockey player skate? Hockey is a fast-paced sport, no matter who\u2019s playing. But many professional players can speed down the rink at more than 20 miles (32 km) per hour. Many can go faster than 30 miles (48 km) per hour! What enables hockey players to skate so fast? When a skater accelerates, they dig the blades of their skates into the ice, lean forward and push off. Because they are leaning, gravity pulls the center of their body down, which pushes their upper body forward. They also dig in with their blades, to get a good grip on the slippery ice. This causes friction, which causes resistance. That resistance makes it easier for a player to push against the ice. It also increases the forces that move the player forward. 76 P O PU L AR SC I E N C E K I DS","what is the controversy with curling? Curling is one of the world\u2019s oldest sports, dating back to at least the 1500s. It\u2019s pretty low-tech: just a broom, a heavy polished stone and a sheet of ice. The ice and the stone haven\u2019t changed much, but new broom technologies have led to some controversy. Players are worried that new kinds of fabrics and innovative broom designs could be creating an unfair advantage. These so-called Frankenbrooms have been banned from World Curling Federation competition. how do figure skaters spin so fast? It\u2019s all about the science of physics! A \ufb01gure skater who\u2019s moving in a straight line is able to go very fast because of linear momentum. Linear momentum is the skater\u2019s body mass multiplied by velocity (speed). When a skater starts spinning, however, linear momentum changes to angular momentum. Angular momentum depends on how fast something is spinning (angular velocity) and how far something sticks out from the center of the spinning object. That\u2019s why when \ufb01gure skaters want to spin faster, they tuck their arms close to the body. 77","SPORTS who are the winningest which basketball siblings in tennis? player scored 100 points in a Maybe it\u2019s because the game takes at least single game? two players that so many siblings make a career of tennis. Two pairs of siblings Philadelphia Warriors center Wilt stand out above the rest. Bob and Mike Chamberlain scored 100 points in a Bryan are identical twin brothers with a single game\u2014something never done record-breaking 119 wins in doubles plus an before or since. It happened on March Olympic gold medal. But by a wide margin, 2, 1962, when the Warriors beat the Serena and Venus Williams claim the title of New York Knicks 169\u2013147. His last two the winningest sibs in the game. Partners points came with 46 seconds left on in doubles and \ufb01erce rivals on the singles the clock. Whose court, they have 30 Grand Slam singles record did he titles between them; 14 doubles titles break? His own! together in the major tournaments; and Chamberlain nine Olympic medals, including three golds. had scored 78 points in a game three months earlier. what is the longest jump on skis? Austrian skier Stefan Kraft jumped 253.5 meters (831.69 feet) in Vikersund, Norway, on March 18, 2017. Completing his jump during the FIS Ski Jumping World Cup, Kraft earned the Guinness World Record for longest competitive ski jump by a male. 78 P O PU L AR SC I E N C E K I DS","what are some surprising former Olympic sports? Rules about the sports to be played in the Olympics were set forth in the Olympic Charter, issued in 1908. Popularity of a sport in a large number of countries was one of the requirements for consideration. Skateboarding (park and street) is one of the newest sports added. It might surprise you to know what sports were popular a century ago, long before the \ufb01rst skateboard was even invented. Tug of war was included at the Olympics from 1900 to 1920. Other unusual Olympic competitions from that era include rope climbing and croquet. who is the which soccer fastest human? player has scored the most goals in In 2009, Jamaican sprinter Usain international play? Bolt became the fastest person in history when he set the world Christine Sinclair of Canada has 190 record in the 100-meter sprint with international goals (as of September 2022), a blistering 9.58 seconds. Bolt raced the most of any active women\u2019s or men\u2019s down the track at an average speed soccer player. The most successful soccer of 23.35 miles per hour (37.58 kph). player to compete for Canada, Sinclair During the same track meet, he also started playing when she was 4 years old. set the world record for the 200- meter sprint: 19.19 seconds. In 2011, 79 scientists used lasers to track how fast Bolt was moving at different parts of a 100-meter race. They found that at 67.13 meters into the race, Bolt was bolting down the track at 27.33 miles per hour (43.99 kph).","CHAPTER 5 SCIENCE Whether they\u2019re studying the tiniest electrons, the deepest oceans or the most far-flung stars, scientists challenge us to ask questions about our world. Some science is very theoretical, meaning it can be tough to see how it relates to your life. But lots of science is also practical. Everything around you\u2014the food you eat, the clothes you wear, the games you play, even the ground beneath your feet\u2014has been poked, prodded, questioned, explored and, in many instances, improved by science.","Light waves refract (bend) when passing through a prism, splitting white light into its visible spectrum of colors. Sound waves are vibrations that can be heard by us.","SCIENCE what is a chemical reaction? S imply put, a chemical reaction is a process that transforms one set of substances into another. When you toast bread, for example, the heat from the toaster changes the bread\u2019s molecules, giving it that crispy exterior and yummy smell. A different type of chemical reaction involves breaking something down. When you eat that toast, it \ufb01rst mixes with the saliva in your mouth and begins to break down. This starts the chemical reactions that allow your body to digest the toast and absorb its nutrients. what does chemistry have to do with plants? Plants use a chemical reaction that\u2019s called photosynthesis to make the food they need in order to grow. For photosynthesis to occur, plants need three things: light, carbon dioxide (CO2) and water. Plants contain chlorophyll (KLOR-uh-\ufb01ll), a chemical that they use to gather light energy. (Chlorophyll is green, which explains why so many plants are also green.) With light energy powering the reaction, the CO2 in the air interacts with water particles within the plant to produce carbohydrates (sugars), which the plants use to grow.","what causes a rocket to lift off? A rocket rises from its launchpad because of a chemical reaction called combustion. Combustion is created when oxygen and heat interact with some form of fuel. Imagine a match: The red bit on top is covered with phosphorus, a chemical that acts as the fuel. The air around you provides the oxygen, and you create the heat, in the form of friction, when you strike the match against a hard, rough surface. In a traditional rocket, a type of aluminum serves as the fuel, a type of ammonia provides the oxygen and the engine provides the heat. This reaction then causes a controlled reaction, called combustion, which releases exhaust (the smoke and \ufb02ame you see when a rocket takes off). When the exhaust is released from the bottom of the rocket, it creates thrust in the opposite direction. Thrust is the force that pushes the rocket up. what makes dough rise? Making bread or pizza depends on a chemical reaction called fermentation. To cause this reaction, yeast (a type of fungi) is mixed with warm water and a little sugar, and added to \ufb02our. (The warmth of the water matters because chemical reactions need some heat.) The yeast gobbles up starch in the sugar and \ufb02our and turns it into CO2. The gas makes bubbles in the dough, which causes the dough to expand, or rise. The bubbles make it possible for breads and pizza crusts to have a soft texture inside even when their outsides are crunchy. why did the Statue of Liberty change colors? You may know her for her famous green hue, but this symbol of freedom wasn\u2019t always that color. In fact, when she was unveiled in 1886, Lady Liberty was a shiny, brownish-red\u2014just like a penny. That\u2019s because both the statue and the coin are made out of copper! By 1906, her metal had oxidized, covering the \ufb01gure in a green patina. Oxidation occurs when air and water interact with the molecules in copper, forming copper oxide and coating the surface with the blue-green color. This can also happen with things like watering cans, bicycle chains and barbecue grills, which will turn a dark red or brown\u2014otherwise known as rust! 83","SCIENCE Cadmium what This soft metal was is the originally famous for its use periodic in oil paints. Today it\u2019s used in batteries, nuclear reactors table? and solar power cells. Atomic Number 48 I n 1869, Russian chemist Dmitri Atomic Symbol Cd Mendeleev got bored while on a long train trip. To keep busy, Radium he began arranging the known elements into a table, putting those Radium is highly radioactive. with similar properties together. It was once used to An element is a substance, like manufacture glow-in-the- hydrogen, that can\u2019t be broken down dark watches and instrument into anything smaller. That train trip dials. Today, it is used in was step one in the periodic table. certain cancer treatments. Atomic Number 88 Mendeleev understood that Atomic Symbol Ra his work was far from complete. Studying the patterns in his table, he Dysprosium could see there were gaps. The empty spots suggested that some elements Dysprosium was discovered had not yet been discovered. in 1886, but because it Scientists continue to \ufb01ll in the gaps occurs only as part of in the periodic table today. compounds, scientists couldn\u2019t study it alone until 1950. Its name means \u201chard to get at\u201d in Greek. Atomic Number 66 Atomic Symbol Dy","Carbon Neon All organic material contains When this colorless, odorless carbon. Diamonds are a gas is exposed to electricity, it form of pure carbon, and so glows\u2014which is why it has been is the black part of pencils, used to create bright signs for called graphite. more than a hundred years. Atomic Number 6 Atomic Number 10 Atomic Symbol C Atomic Symbol Ne Einsteinium Mercury Named to honor the famous The symbol for mercury comes physicist Albert Einstein, from its ancient Greek name, this element was discovered hydragyrum, or \u201cliquid silver\u201d\u2014 in 1952, when scientists a perfect description of the studied the remains of a element, which is liquid at hydrogen bomb explosion. room temperature. Atomic Number 99 Atomic Number 80 Atomic Symbol Es Atomic Symbol Hg","SCIENCE what is so special about the planet Earth? T he Earth is about 4.5 billion years old and is the only planet in our solar system that contains intelligent life. We live on a very small bit of Earth, a thin biosphere (the part where life exists) that is not typical of the rest of the planet. If you could dig a hole a few dozen miles below the surface, you would see nothing but rocks, minerals and metallic compounds. A few miles above the surface, the entire planet is shrouded in a cocoon of gases\u2014 the atmosphere. Earth is a geoid, which means it\u2019s not perfectly round. This is because the planet rotates so fast\u2014once every 24 hours\u2014that gravity causes it to bulge outward at the equator. 1\/ Crust The Earth\u2019s crust is the outermost layer and the place where we live. Compared to the rest of the planet, the crust is very thin\u2014about 3 to 5 miles (4.8 to 8 km) under the oceans and about 25 miles (40 km) under the continents. The crust is like a cracked eggshell; each piece is a tectonic plate. These plates are always on the move, \ufb02oating on the mantle, and crashing and hammering into one another. 2\/ Mantle The mantle is the thickest layer, a hot region of dense, semisolid rock around 1,801 miles (2,900 km) deep. 3\/ Core The core\u2014the center of the planet\u2014is nearly two times as dense as the mantle and is made up of a liquid outer core and a solid inner core. The outer core is mostly melted iron and nickel. Its temperature is a scalding 7,232\u00b0F (4,000\u00b0C ). 86 POPUL AR SC IENCE KIDS","Crust Upper Mantle Mantle Outer Core Inner Core how does the planet\u2019s magnetic field work? Earth has a magnetic \ufb01eld. Scientists are pretty sure this \ufb01eld, which behaves like a powerful bar magnet, is produced by the swirling of liquid iron in Earth\u2019s outer core. As the molten iron swirls, it creates electrical currents with the two poles of the magnet that are located near the top and bottom of the planet\u2014the North and South Poles. 87","SCIENCE what are gems and minerals? A mineral is a type of rock\u2014an inorganic (nonliving) substance that\u2019s found in nature. Gemstones are types of minerals that stand out from the rest because of their beauty. why don\u2019t diamonds melt? At a high enough temperature, almost everything will melt...but not diamonds. That\u2019s because diamonds are made of pure carbon. The melting point of carbon is so high that before a diamond would melt, it will burn. The burning causes the diamond to release carbon dioxide gas, and what remains is graphite\u2014in other words, it\u2019s not a diamond anymore. A diamond can\u2019t melt and still be a diamond. when is jade not green... and not jade? There are actually two minerals that are called jade: jadeite and nephrite. They look very similar\u2014you would need to be an expert to tell the difference\u2014but they have different chemical compositions and crystal structures. Nephrite is slightly softer than jadeite, ranges in color from dark green to gray-green and can also be white, yellowish or reddish. Jadeite comes in a wider range of colors, including green, lavender, yellow, black and white. The colors of all types of jade are determined by their chemical composition.","why do some rocks seem to glow? Some rocks glow because of the minerals they contain. The electrons in the minerals become excited by ultraviolet (UV) light. (When you\u2019re talking about electrons, \u201cexcited\u201d means they have an increase in energy.) Excited electrons cause minerals to emit light waves that we see as a glow. For many minerals, this only happens under UV light, a phenomenon called \ufb02uorescence. There are about 500 types of minerals that are \ufb02uorescent. Other minerals continue to glow for a while, even after the UV light is gone, because their electrons remain excited. That\u2019s called phosphorescence. why do watches have gems? Watches have lots of very tiny moving parts inside. For a watch to keep accurate time, all those parts need to work together smoothly. But when tiny metal parts rub against one another, they create friction. Over time, friction can cause parts to wear out, making the watch inaccurate. In the 18th century, watchmakers realized that they could use small diamonds, sapphires and rubies\u2014which are harder than metal and don\u2019t wear out\u2014to make watches work better. Watches today generally have synthetic gems inside, rather than real ones.","SCIENCE what is the big deal with chemical reactions? how does In an engine, a chemical reaction science between fuel and air releases energy called combustion. When help race designing race cars, engineers try cars go to get maximum energy from those explosions. For example, race cars faster? have devices called cold-air intakes, which pull cooler outside air into A t a racetrack, a split second can the engine. Cooler air has more make the difference between oxygen than hot air, so it creates a \ufb01rst and second place. Engineers who more powerful explosion. design race cars use science to make their cars as fast as possible. Rolling Friction Whether you\u2019re throwing a ball, what\u2019s the fastest racing around a track or just walking a car has ever gone? across a room, all moving objects are acted upon by unseen forces. The Talladega Superspeedway in Automotive engineers understand Alabama was the site of Bill Elliott\u2019s these forces well: They include famous NASCAR race, in which friction, drag and resistance. he hit a record-setting top speed Designers apply their knowledge of of 212.809 mph (342.483 kph). these forces to every aspect of a car, Elliot set that record in his Ford from the engine to the body shape to Thunderbird back in 1987\u2014and so the tires. The goal is always the same: far, no one has been able to beat it. to increase the power of the forces that create speed while reducing the forces that slow things down. An understanding of chemical reactions can also help engineers make cars go even faster. Here are some examples of how an understanding of science helps race car designers. 90 POPUL AR SC IENCE KIDS","why does resistance matter? Imagine moving your hand through water. The water pushes against you a tiny bit\u2014 that\u2019s resistance. Air does the same, but if you aren\u2019t moving fast, you don\u2019t notice. With a race car, though, resistance is a big problem. It\u2019s often called drag. The shape of a car reduces drag by enabling the air to \ufb02ow around the car as smoothly as possible. what role does friction play? how is pressure controlled? When two objects rub against each other, it creates friction. Friction can be useful at Race car tires are in\ufb02ated times\u2014for example, it\u2019s what allows brakes with nitrogen rather to stop a car. But friction inside engines is than ordinary air. That\u2019s bad: It slows things down and causes parts because air contains to wear out more quickly. Motor oil reduces water molecules. Water friction in all car engines, not just in race can lead to uneven cars. But there are many specialized race car pressure inside the tire, oils that vary in viscosity. Which oil is best which slows the car depends on numerous factors\u2014two important down. Plus when the car ones are the type of engine and the weather. speeds around the track, the wheels heat up, which increases pressure. Too much pressure will make the tire burst\u2014a racer\u2019s worst nightmare! Pure nitrogen has no water molecules and keeps tire pressure consistent.","SCIENCE what is a rainbow? W hat we experience as color is actually different wavelengths of light. Sunlight may look white, but in fact, it contains all the colors at once. If there is water in the air, such as right after a rainstorm or when you\u2019re watering the garden, the light passes through those water droplets before it reaches your eyes. The water droplets cause the light to slow down and bend\u2014this is called refraction. When sunlight is refracted, the colors get broken up, making it possible to see them individually, in the form of a rainbow. Although you might not be able to identify every color every time, a rainbow always has seven colors: red, orange, yellow, green, blue, indigo and violet.","6 ILLUMINATING FACTS YOU MAY NOT KNOW ABOUT RAINBOWS 1\/ Under the right conditions, a lunar rainbow can form at night. Also called a moonbow, it most often forms near waterfalls. 2\/ Rainbows are curved because different wavelengths of light bend differently. For example, red light moving through water will bend at about a 42-degree angle, while violet light bends at about a 40-degree angle. 3\/ Rainbows have no beginning or end\u2014 they are actually circles. They look like arches because we are on the ground and can\u2019t see them entirely. 4\/ How much of a rainbow you can see depends on how high the sun is in the sky. Very early and very late in the day are when you will see the largest rainbows, due to the angle of light. 5\/ A double rainbow occurs when light waves are refracted more than once. The second rainbow is fainter than the main one because as the light waves bounce around, they lose energy. Double rainbows are actually common\u2014 but because they are faint, they can be dif\ufb01cult to see. 6\/ If light refracts through ice crystals, a different effect is created. It\u2019s called a sun dog. Sun dogs look a bit like mini rainbows on either side of or as a halo around the sun. 93","SCIENCE whydo scientists ask \u201cwhat if\u2026\u201d? O ne of the most common reasons people become scientists is a deep curiosity about how things work. When scientists ask \u201cWhat if\u2026\u201d they\u2019re combining the knowledge they already have with their theories of what might be. Whether they are working to improve the environment, cure diseases, understand the ancient past or even solve crimes, \u201cWhat if\u2026\u201d has spurred scientists to do more than just hypothesize. It has inspired the scientists pro\ufb01led here to work toward not only understanding our world but making it better. what if science can end a global crisis? The scientists U\u011fur \u015eahin and \u00d6zlem T\u00fcreci have a lot in common. Both grew up in Germany and are of Turkish descent. They met while studying medicine and married in 2002. Later they founded BioNTech, a company that develops gene therapies to treat cancer. When \u015eahin read about the COVID- 19 coronavirus in January 2020, he announced that the BioNTech company would shift from \ufb01ghting cancer to \ufb01ghting COVID-19. By March, \u015eahin and T\u00fcreci\u2019s team had created nearly two dozen vaccines for study; by November, the team had found a successful one. In early December 2020, U.K. resident Margaret Keenan was the \ufb01rst person to receive that vaccine. Since then, billions of doses have been administered.","what if science can heal the Earth? Biologist Wangara Maathi was born in Nyeri, Kenya, in 1940. She saw the toll deforestation was taking on her country. She wrote, \u201cIf you destroy the forest, then the river will stop \ufb02owing, the rains will become irregular, the crops will fail and you will die of hunger and starvation.\u201d She understood how humans and the environment are connected and how damage to one will damage the other. This insight led her to found the Green Belt Movement, which uses tree-planting projects to create jobs in rural villages. By 2021, the Green Belt Movement had planted more than 51 million trees in Kenya. what if science can measure the immeasurable? Astronomer Henrietta Swan Leavitt graduated from Radcliffe College in 1892. During her career, Leavitt discovered more than 2,400 stars, which doubled the number of known stars at the time. Her specialty was photometry, which is the study of the brightness of light. By studying photographs of stars known as Cepheid variables, she made discoveries about the relationship between the brightness of a star and its distance from Earth. Leavitt\u2019s work made it possible to measure our Milky Way galaxy for the \ufb01rst time. what if science can bring about justice? In 1832, James Marsh\u2014a chemist in London\u2014was asked by police to help investigate a man named John Bodie, who was suspected of murdering his grandfather by putting arsenic in his coffee. Marsh tried to help, but Bodie was ultimately found not guilty (though he later confessed to the crime). Marsh vowed not to let this happen again. He created a laboratory test that could prove the presence of arsenic in a sample of tissue from a body\u2014a big step forward in the science of criminal forensics. 95","SCIENCE what Venus Flytrap Sea Anemone was the biggest ocean exploration? B eginning in 2000, more than 2,700 scientists from 80 countries conducted a Census of Marine Life. They found 148,235 marine species, including more than 1,000 that were previously unknown. For example, the Atolla jelly\ufb01sh was found in deep water off the coast of a Japanese island. When threatened, the body of an Atolla jelly\ufb01sh lights up like an alarm\u2014scientists have described it as a bioluminescent scream. All the data is available online, as part of the Ocean Biodiversity Information System (obis.org). Atolla Jelly\ufb01sh Zombie Worm Sargassum Frog\ufb01sh","who made a mistake that saved millions of lives? When Scottish doctor Alexander Fleming left a petri dish containing bacteria by an open window, mold began to grow in it. Fleming noticed that something in the mold prevented the bacteria from growing on it. He \ufb01rst called the substance \u201cmold juice.\u201d Eventually he settled on a name you probably know, penicillin. Penicillin is now used by doctors to cure all types of infections. By one estimate, Fleming\u2019s discovery has saved as many as 200 million lives. what was the most mysterious experiment? At Oxford University in the U.K., a bell has been ringing constantly for the past 175 years. Known as the Oxford Electric Bell, it was installed in 1840 by professor Robert Walker. The experiment had to do with the equipment\u2019s unique design\u2014it has two bells, one on either side of a battery. The mystery is, no one can \ufb01gure out why the battery still works after all this time. One of the longest- running experiments ever, the bell is on display at Oxford\u2019s Clarendon Building. 97","THE PHOTO CREDITS The U.S. sent a total of 12 astronauts ULTIMATE KEY Alamy\u2014AL; Getty Images\u2014GY; iStock\u2014IS; Shutterstock\u2014SS GUIDE to the moon from COVER Sripfoto\/SS; \ufb02ashpict\/SS; stockcam\/GY; Dotted Yeti\/SS; Bored 1969 to 1972. Now EVER(AYLMTOTOSHT) ING Photography\/SS; Christy Liem\/SS; Christian Musat\/SS; Radha Design\/SS; NASA is planning a Henrik5000\/GY; Max keg\ufb01re\/SS; fotoVoyager\/GY; Somchai Som\/SS; Dan new generation of Creative Director Thornberg\/SS; Digital Imaging Specialist: Eric Wolslager 2\u20133 Mike Mareen\/ JESSICA POWER SS 4-5 From top: M.Aurelius\/SS; Westend61\/GY; Gorodenkoff\/SS; lunar missions. feelphoto\/SS; Mike Mareen\/SS 6 \u00a9NASA\/JPL-Caltech; \u00a9M.Aurelius\/SS Executive Editor 7 \u00a9NASA, ESA, A. Simon (Goddard Space Flight CTR), and M.H. 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