Universe - The Definitive Visual Guide (September 2012)

["","400 THE CONSTELLATIONS THE ARCHER Although old star charts depicted this Omega Nebula, M17.The loose Sagittarius constellation as a centaur, in Greek cluster of stars within it can be SIZE RANKING 15 mythology Sagittarius was identified detected through binoculars. BRIGHTEST STAR as a different type of creature, known M22 is one of the finest globular Epsilon (\u03b5) 1.8 as a satyr. He is usually said to be clusters in the entire sky. Under good GENITIVE Sagittarii Crotus, son of Pan, who invented conditions, it is visible to the naked ABBREVIATION Sgr archery and went hunting on eye.Through a small telescope, it is HIGHEST IN SKY AT 10 PM horseback. He is seen aiming his somewhat elliptical in outline, while July\u2013August bow at neighboring Scorpius. one with an aperture of 3 in (75 mm) FULLY VISIBLE will resolve its brightest stars. 44\u00b0N\u201390\u00b0S SPECIFIC FEATURES M23 is a large open cluster visible This prominent zodiacal constellation Beta (\u03b2) Sagittarii appears to the through binoculars near the border M22 15 is found between Scorpius and naked eye as a pair of 4th-magnitude with Ophiuchus. M25 is another This prominent globular cluster lies near the Capricornus, in the southern celestial stars.The more northerly (and slightly binocular cluster, while M24 is a lid of the Teapot. Through binoculars, it hemisphere. It includes a highly brighter) of the two stars has a 7th- bright Milky Way star field the length appears as a woolly ball about two-thirds recognizable star pattern called the Teapot, with a pointed lid (\u03bb) and magnitude companion. All three stars of four diameters of a full moon. the apparent diameter of a full moon. large spout (\u03b3, \u03b5, and \u03b4).The handle of the Teapot is sometimes also called are at different distances, the Milk Dipper. and thus are unrelated. 20h 19h 18h The Milky Way is particularly Probably the finest broad and rich in Sagittarius, because AQUARIUS OPHIUCHUS the center of our Galaxy (Sagittarius object for binoculars is A) lies in this direction.The exact center of the Galaxy is thought to M8, the Lagoon Nebula CAPRICORNUS SERPENS coincide with a radio source known (see p.243), which CAUDA as Sagittarius A*, near where the borders of Sagittarius, Ophiuchus, and extends for three times NGC 6818 SCUTUM Scorpius meet. Sagittarius boasts more Messier objects than any other the width of a full NGC 6822 \u03c5 constellation\u2014it has 15 in all. 56 \u03c11 moon. It contains the M17 cluster NGC 6530, with 43 NGC M18 6716 M25 Y M24 M23 stars of 7th magnitude \u03c0 \u03bc \u03bf M21 and fainter, as well as the \u03be\u03bd1,12,2 21 6th-magnitude blue \u02da-20 M75 ECLIPTIC 11 M20 supergiant 9 Sagittarii. \u03c8 M22 \u03bb M28 The Trifid Nebula, 60 52 Nunki 4 M55 M20 (see p.246), is so \u03c9 \u03b6\u03c3 \u03d5 M8 named because it is 62 59 \u03c4 TEAPOT X RR trisected by dark lanes W of dust.Visually, it is far MILK M69 \u03b4 \u03b3 Sgr A* DIPPER M54 less impressive than its \u02da-30 SAGITTARIUS photographic representation, \u03b5M70 Kaus \u03b81 Australis and little more than the faint \u03b7 double star at its center can NGC 6723 SCORPIUS be identified through a small Shaula instrument. CORONA On the northern border \u02da-40 \u03b1 AUSTRALIS of Sagittarius with Scutum \u03b9 \u03b21 lies another frequently photographed object\u2014the \u03b22 TELESCOPIUM THE LAGOON NEBULA 154 One of the largest nebulae in the sky INDUS ARA is M8, which appears in binoculars as an elongated, milky patch of light with embedded stars, including those in the \u02da-50 cluster NGC 6530, which make it glow. THE ARCHER THE NIGHT SKY THE TRIFID NEBULA 54 THE OMEGA NEBULA The pinkish emission of the Trifid 154 Nebula contrasts with the blue M17 can be glimpsed reflection nebula to its north, through binoculars but as revealed on long-exposure shows up better through a photographs and CCD images. telescope. It resembles At its heart is a faint double star, the Greek capital letter which is overexposed on this image. omega (\u03a9). However, others see it as a swan, hence its alternative name, the Swan Nebula.","401 MOUNTED BOWMAN 2 The stars that make up the outline of Sagittarius, the Archer, lie in front of dense Milky Way star fields toward the center of our Galaxy. North is to the left in this photograph. THE NIGHT SKY","","","","","","","","","410 THE CONSTELLATIONS THE SAILS UNDER SAIL 2 Vela represents the mainsail of the Argo, the Vela ship of Jason and the Argonauts, sailing through the southern sky in the quest for the SIZE RANKING 32 golden fleece. BRIGHTEST STAR THE EIGHT-BURST NEBULA 54 The planetary nebula NGC 3132 has loops of Gamma (\u03b3) 1.8 gas that interlock like figure-eights, hence GENITIVE Velorum the object\u2019s popular name. ABBREVIATION Vel HIGHEST IN SKY AT 10 PM February\u2013April FULLY VISIBLE 32\u00b0N\u201390\u00b0S In the 18th century, the ancient wider companions, with components Greek constellation Argo Navis (the of 8th and 9th magnitudes, are visible ship of Jason and the Argonauts\u2014see through a telescope. panel, below) was divided into three parts, one of which was Vela, which IC 2391 is the best star cluster in represents the ship\u2019s sails. Because the Vela for the naked eye or binoculars. stars labeled Alpha (\u03b1) and Beta (\u03b2) It is a group of several dozen stars in the former Argo Navis are now in covering a greater area than a full Carina, to the south, the labeling of moon.To the north of it is another the stars in Vela starts with Gamma (\u03b3) binocular cluster, IC 2395. Velorum, or Regor (see p.253). NGC 2547 is an open cluster half Between Gamma and Lambda (\u03bb) the size of a full moon and can be Velorum are found the gaseous identified through binoculars or a strands of the Vela supernova remnant small telescope. (see p.269)\u2014the supernova could have been seen from Earth around Popularly known as the Eight- 11,000 years ago\u2014while Delta (\u03b4) Burst Nebula, NGC 3132 has and Kappa (\u03ba) Velorum combine with complex loops that are revealed only two stars in Carina to form the False through a large telescope or on long- Cross (sometimes mistaken for the exposure photographs. A small true Southern Cross). telescope will show the nebula\u2019s disk, of similar apparent size to Jupiter, and the 10th-magnitude star at its center. SPECIFIC FEATURES THE SAILS Gamma Velorum is the brightest example of a Wolf\u2013Rayet star, a rare type of star that has lost its outer layers, thereby exposing its ultra-hot interior. A 4th-magnitude companion is visible through a small telescope or good binoculars. In addition, two MYTHS AND STORIES ANTLIA PYXIS THE ARGONAUTS NGC 3132 \u03c8\u03bb \u02da-40 The Argo was a mighty 50-oared NGC 3201 VELA PUPPIS galley in which Jason and 50 of the greatest Greek heroes, called \u03b3 \u02da-50 the Argonauts, sailed to Colchis, on the eastern shore of the Black \u03bc IC 2395 Sea, on their mission to find the golden fleece of a ram.Their epic CENT- NGC 3228 \u03bf NGC 2547 voyage is one of the great stories AURUS \u03ba IC 2391 of Greek myth. \u03d5 \u03b4 LEGENDARY SAILING GALLEY The Argo, ship of the Argonauts, is here IC 2488 depicted by the Italian artist Lorenzo Costa (1459\u20131535). THE NIGHT SKY CARINA 8h 10h 9h 11h IC 2391 21 Omicron (\u03bf) Velorum, at magnitude 3.6, is the brightest member of IC 2391, a scattered cluster that lies some 500 light-years from Earth in the southern reaches of Vela.","9h 7h 411 10h THE KEEL 6h VELA Carina PUPPIS \u03c7 THE KEEL \u03b1 SIZE RANKING 34 CARINA Canopus BRIGHTEST STAR NGC 3293 IC NGC \u03b9 \u03b5 NGC 3532 3114 Canopus (\u03b1) -0.6 \u03b7 2581 GENITIVE Carinae l R NGC 2808 NGC 2516 ABBREVIATION Car NGC S \u03c5 PICTOR 3372 HIGHEST IN SKY AT 10 PM Gacrux January\u2013April IC 2602 FULLY VISIBLE CRUX \u03b8 \u03b2 VOLANS 14\u00b0N\u201390\u00b0S DORADO Acrux \u03c9 Carina is a major southern unusual variable star that flared up MUSCA constellation that was originally part during the 19th century to become of the larger figure of Argo Navis, temporarily the second-brightest star in \u02da-70 which depicted a ship, until that was the sky, although it has now subsided to split up in the 18th century. Carina around 5th magnitude. A shell of gas CHAMAELEON represents the ship\u2019s keel. around Eta, which was thrown off during the outburst, is visible through a \u02da-80 Its most prominent star, Canopus, telescope, next to the Keyhole Nebula, or Alpha (\u03b1) Carinae, is a white which appears as a dark and bulbous supergiant 310 light-years away and cloud of dust silhouetted against the second in brightness only to Sirius in glowing gas of the Carina Nebula. the entire sky.The stars Epsilon (\u03b5) and Iota (\u03b9) Carinae form a pseudo A glorious sight through binoculars, \u201csouthern cross,\u201d known as the False another treasure is IC 2602, an open Cross, in conjunction with two stars cluster known as the Southern Pleiades. in neighboring Vela. Twice the apparent size of a full moon, it contains several stars visible to the SPECIFIC FEATURES naked eye\u2014the brightest being 3rd- Splashed across the Milky Way near magnitude Theta (\u03b8) Carinae. the border with Centaurus and Vela is the Carina Nebula, NGC 3372 (see Among Carina\u2019s naked-eye clusters p.247), a patch of glowing gas four is NGC 3532. At its widest point, this diameters of a full moon wide. It is elongated group of stars is twice the visible to the eye and well seen width of a full moon. NGC 3114 is through binoculars.The densest and about the same apparent size as a full brightest part of the nebula is around moon, its brightest individual members Eta (\u03b7) Carinae (see p.262), an being visible through binoculars. NGC 2516 is sparser and appears cross-shaped through binoculars. Its brightest star is a 5th-magnitude red giant. ELONGATED CLUSTER 1 What appears to be the brightest member of NGC 3532, in the lower left of this photograph, is in fact an extremely luminous background star some four times farther off. THE CARINA NEBULA 215 The brightest part of this immense cloud of glowing gas is V-shaped (shown here), while the star Eta (\u03b7) Carinae itself (below left of center) is a peculiar variable that appears as a hazy orange ellipse. EVEN KEEL 2 THE NIGHT SKY Carina represents the keel and hull of the Argonauts\u2019 ship, the Argo. The blade of the steering oar is marked by Canopus, Carina\u2019s brightest star.","412 THE CONSTELLATIONS THE SOUTHERN CROSS supergiant that contrasts with the VELA blue-white sparkle of the other stars, Crux producing a resemblance to a casket \u02da-50 of jewels, hence the popular name. SIZE RANKING 88 CENTAURUS The Coalsack Nebula is to be BRIGHTEST STARS Acrux found beside the Jewel Box.This dark \u03bc \u03b3 CRUX (\u03b1) 0.8, Becrux (or cloud of dust blocks light from the Mimosa) (\u03b2) 1.3 stars of the Milky Way behind it. It \u03bb\u03b2 \u03b4 GENITIVE Crucis spans the width of 12 full moons and extends into neighboring Centaurus \u02da-60 NGC \u03b9 \u03b5 \u03b81,2 ABBREVIATION Cru and Musca, so it is prominent to the Hadar 4755 \u03b1 naked eye and through binoculars. Coal- HIGHEST IN SKY AT 10 PM sack \u03b6 CARINA April\u2013May Acrux FULLY VISIBLE \u03b7 25\u00b0N\u201390\u00b0S THE SOUTHERN CROSS MUSCA \u02da-70 14h 13h 12h 11h Crux lies in a rich area of the Milky SIGN OF THE CROSS 2 Way. Although it is the smallest Four prominent stars make up the constellation, it is instantly recognizable Southern Cross, one of the most famous and is squeezed between the legs of of all celestial patterns, which appears the centaur, Centaurus.The longer on the flags of several nations. axis of the Southern Cross, as Crux is popularly known, points toward the EXPLORING SPACE south celestial pole. Its stars were known to the ancient Greeks (see REDISCOVERING STARS panel, below), who regarded them as part of Centaurus.They were made When European seafarers returned from into a separate constellation in exploring the southern latitudes in the 15th the 16th century. and 16th centuries, they reported stars they had never seen before. Among these SPECIFIC FEATURES Alpha (\u03b1) Crucis or Acrux is the explorers was Amerigo Vespucci (1454- most southerly first-magnitude star. 1512), an Italian who in 1501 charted It is a glittering double that is readily Alpha (\u03b1) and Beta (\u03b2) Centauri and the divisible through a small telescope. The two components are of stars of Crux. Astronomers later realized magnitudes 1.3 and 1.8. A wider 5th- that these stars had been known to the magnitude star can be seen through ancient Greeks but that precession (see binoculars; it is not related to Acrux. p.64) had subsequently carried them below the horizon in Europe. The star at the top of the cross is the 2nd-magnitude red giant Gamma AMERIGO VESPUCCI (\u03b3) Crucis or Gacrux. It has an This imaginative view of Amerigo Vespucci unrelated 6th-magnitude companion observing the Southern Cross with an astrolabe visible through binoculars. Nearby, was painted by the 16th-century Flemish artist Mu (\u03bc) Crucis is a wide pair of Joannes Stradanus (Hans van der Straet). 4th- and 5th-magnitude stars easily separated through a small telescope or even good binoculars. One of the gems of the southern sky is the Jewel Box Cluster (see p.294), or NGC 4755, visible to the naked eye as a brighter patch within the Milky Way near Beta (\u03b2) Crucis or Becrux. Its individual stars, the brightest being of 6th magnitude, cover about one-third the width of a full moon.They can be viewed through binoculars or a small telescope. Near the center is a ruby-colored THE NIGHT SKY THE COALSACK 21 The Coalsack Nebula, which lies next to the stars of the Southern Cross, is a smudgy cloud of interstellar dust silhouetted against the bright background of the Milky Way. JEWELS OF THE SKIES 15 The Jewel Box Cluster is a sparkling group of stars just north of the Coalsack Nebula, although the cluster is almost ten times more distant from Earth.","THE CONSTELLATIONS 413 THE FLY Musca SIZE RANKING 77 NGC 4833 15 This globular cluster is BRIGHTEST STAR just visible through binoculars. Individual Alpha (\u03b1) 2.7 stars can be resolved GENITIVE Muscae with a telescope of 4-in (100 mm) aperture. ABBREVIATION Mus HIGHEST IN SKY AT 10 PM April\u2013May FULLY VISIBLE 14\u00b0N\u201390\u00b0S This modest constellation is to be CRUX found in the Milky Way south of Crux and Centaurus. In fact, the Hadar southern tip of the dark Coalsack Nebula extends into it from Crux. CENTAURUS Acrux Musca is one of the southern -60\u00b0 Rigil Kentaurus \u03b8 constellations introduced at the end of the 16th century by the Dutch \u03b7\u03b2 \u03b5 \u03bc\u03bb CARINA navigator-astronomers Pieter \u03b1 Dirkszoon Keyser and Frederick CIRCINUS NGC 4833 de Houtman. It represents a fly. \u03b4\u03b3 SPECIFIC FEATURES Theta (\u03b8) Muscae is a double star -70\u00b0 MUSCA with components of 6th and 8th magnitude, divisible through a small CHAMAELEON FINDING THE FLY 2 telescope.The fainter component is The long axis of the Southern Cross an example of a Wolf\u2013Rayet star\u2014a APUS points to Musca, the fly, which lies on hot star that has lost its outer layers. the edge of the Milky Way within the Musca also has a globular cluster, 14h 13h 12h southern celestial hemisphere. known as NGC 4833 (see p.295). THE FLY THE COMPASS CENTAURUS Circinus SIZE RANKING 85 \u02da-50 NORMA LUPUS BRIGHTEST STAR \u03b3\u03b2 Alpha (\u03b1) 3.2 Hadar GENITIVE Circini \u02da-60 Rigil Kentaurus CRUX ABBREVIATION Cir \u03b5 HIGHEST IN SKY AT 10 PM \u03b1 May\u2013June FULLY VISIBLE 19\u00b0N\u201390\u00b0S CIRCINUS Circinus represents a dividing TRIANGULUM MUSCA compass, as used by surveyors and AUSTRALE navigators. It is one of the figures 14h introduced in the 18th century by the 16h 15h French astronomer Nicolas Louis de Lacaille (see p.422). THE COMPASS This small southern constellation GEOMETRIC SHAPE 2 THE NIGHT SKY is squeezed awkwardly in between Circinus forms a slim Centaurus and Triangulum Australe. triangle of stars and is It lies next to Alpha (\u03b1) Centauri, so squashed into a sliver of it is not difficult to locate. the southern sky next to the brilliant Alpha (\u03b1) SPECIFIC FEATURES and Beta (\u03b2) Centauri. Circinus contains little of interest for amateur astronomers. Alpha (\u03b1) Circini, however, is its one star of note. It is situated against the background of the Milky Way and is easy to identify, being a double with components of 3rd and 9th magnitudes.These are divisible through a small telescope.","414 THE CONSTELLATIONS THE SET SQUARE Norma SIZE RANKING 74 NGC 6067 15 This rich cluster covers BRIGHTEST STAR an area of sky about half the apparent Gamma-2 (\u03b32) 4.0 diameter of a full GENITIVE Normae moon. It is seen ABBREVIATION Nor against the backdrop of the HIGHEST IN SKY AT 10 PM Milky Way. June 17h 16h FULLY VISIBLE 29\u00b0N\u201390\u00b0S Norma was introduced in the 1750s by the Frenchman Nicolas Louis de Lacaille (see p.422), and was originally known as Norma et Regula, the square and ruler. It is an unremarkable southern constellation lying in the Milky Way between Lupus and the zodiacal constellation of Scorpius. The stars that Lacaille designated Alpha (\u03b1) and Beta (\u03b2) have since been incorporated into Scorpius. SPECIFIC FEATURES SCORPIUS At magnitude 4.0, Gamma-2 (\u03b32) Normae is the constellation\u2019s brightest \u02da-40 star, and it is one-half of a naked-eye double together with Gamma-1 (\u03b31) \u03bc\u03b4 Normae, of magnitude 5.0.The two stars lie at widely different distances \u03b5 and hence are unrelated. \u03b31 \u03b7 Two other doubles in the \u02da-50 NGC \u03b32 NORMA LUPUS constellation that are readily separated 6167 CENTAURUS through a small telescope are Epsilon (\u03b5) Normae, with components of 5th ARA NGC 6067 and 7th magnitudes, and Iota-1 (\u03b91) Normae, with components of 5th and \u03ba 8th magnitudes. \u03b92 \u03b91 NGC 6087 is a large open cluster NGC 6087 that has radiating chains of stars, which are visible through binoculars. RIGHT ANGLE 2 \u02da-60 Near its center is its brightest star, Norma\u2019s most distinctive feature is a S-Normae\u2014a Cepheid variable that right-angled trio of three faint stars, CIRCINUS Rigil ranges in brightness from magnitude which is somewhat difficult to identify 6.1 to 6.8 every 9.8 days. among the rich Milky Way star fields. Kentaurus THE SET SQUARE THE SOUTHERN TRIANGLE Although smaller than its northern SOUTHERN TRIPLET 2 counterpart,Triangulum, this Triangulum Australe is an easily recognized Triangulum Australe constellation contains brighter stars triangle of stars, lying in the Milky Way near SIZE RANKING 83 and so is more prominent. brilliant Alpha (\u03b1) and Beta (\u03b2) Centauri, BRIGHTEST STAR which here are visible on the right. Alpha (\u03b1) 1.9 SPECIFIC FEATURES GENITIVE Trianguli Australis NGC 6025 lies ABBREVIATION TrA on Triangulum ARA CENTAURUS HIGHEST IN SKY AT 10 PM Australe\u2019s northern June\u2013July border with Norma. FULLY VISIBLE It is 2,700 light-years -60\u00b0 NGC 6025 Rigil Hadar away from Earth.This 19\u00b0N\u201390\u00b0S open cluster is noticeably \u03b4\u03b2 Kentaurus elongated in shape and THE NIGHT SKY Triangulum Australe is one of the is about one-third the PAVO \u03b5 CIRCINUS constellations of the southern sky apparent diameter of a full \u03b1\u03b3 that was introduced at the end of the moon. It is easily seen 16th century by the Dutch navigators Pieter Dirkszoon Keyser and through binoculars. -70\u00b0 \u03b6 Frederick de Houtman. It is the Alpha (\u03b1) Trianguli 18h smallest of the 12 they identified. TRIANGULUM Australis is an orange AUSTRALE giant whose color shows prominently 17h 16h 15h through binoculars. 14h There is nothing else in the constellation to attract THE SOUTHERN users of small telescopes. TRIANGLE","Shaula THE CONSTELLATIONS 415 CORONA SCORPIUS INCENSE BURNER 2 AUSTRALIS Ara, the celestial altar, is oriented THE ALTAR with its top facing south. Incense \u03c3 NGC 6193 burning on the altar might give off the Ara \u201csmoke\u201d of the Milky Way above it. SIZE RANKING 63 \u03b8 \u03bb\u03b1 NGC 6352 BRIGHTEST STARS Alpha (\u03b1) 2.8, Beta (\u03b2) 2.8 \u02da-50 NGC 6397 \u03b52 \u03b51 NORMA GENITIVE Arae \u03b2\u03b6 TELESCOPIUM \u03b3 ABBREVIATION Ara \u02da-60 \u03b4 ARA \u03b7 HIGHEST IN SKY AT 10 PM PAVO NGC TRIANGULUM June\u2013July 6362 AUSTRALE 19h FULLY VISIBLE 22\u00b0N\u201390\u00b0S Ara was visualized by the ancient 18h 17h Greeks as the altar on which the 16h gods of Olympus swore an oath of allegiance before their battle with the THE ALTAR Titans for control of the universe (see MYTHS AND STORIES panel, left).This southern constellation lies within the Milky Way and is TITANOMACHIA situated south of Scorpius. Titanomachia, or the Clash of the SPECIFIC FEATURES Titans, was the ten-year war for The attractive open cluster NGC dominance of the universe between 6193 consists of about 30 stars of the gods on Mount Olympus, led 6th magnitude and fainter. It can by Zeus, and the Titans on Mount be viewed through binoculars. Othrys. In gratitude for their victory, Zeus placed the altar of NGC 6397 is among the closest the gods in the sky. globular clusters to us, being around 10,000 light-years away, and can be VICTORY PANEL seen well through binoculars or a Part of the battle of the gods and Titans is small telescope. Like NGC 6193, it here depicted in the Zeus Altar of Pergamon, appears relatively large\u2014both being which was sculpted in Greece c. 180 BC. over half the apparent width of a full moon. Ara contains no stars of particular interest to users of small telescopes. NGC 6397 15 The globular cluster NGC 6397 has a condensed center and scattered outer regions in which chains and sprays of stars can be traced. THE SOUTHERN CROWN SPECIFIC FEATURES SOUTHERN ARC 2 Gamma (\u03b3) Coronae Australis is a Corona Australis is an Corona Australis attractive arc of stars binary star with components of 5th SIZE RANKING 80 BRIGHTEST STARS Alpha magnitude.The pair orbit each other that represents a crown (\u03b1) 4.1, Beta (\u03b2) 4.1 GENITIVE Coronae every 122 years, and they are slowly or laurel wreath. Australis ABBREVIATION CrA moving apart as seen from Earth.This HIGHEST IN SKY AT 10 PM means the components are July\u2013August becoming easier to view FULLY VISIBLE individually. Meanwhile, a 44\u00b0N\u201390\u00b0S 4-in (100-mm) aperture is -30\u00b0 needed to divide this The small southern constellation of challenging star. SAGITTARIUS Corona Australis lies under the feet of Sagittarius. It comprises stars of Kappa (\u03ba) Coronae SCORPIUS 4th magnitude and fainter, and it was one of the 48 constellations Australis is an unrelated \u03b1 \u03b3\u03b5 \u03ba CORONA Shaula THE NIGHT SKY recognized by the ancient Greek double with components of \u03b2 astronomer Ptolemy (see p.347). 6th magnitude, which are -40\u00b0 \u03b4 AUSTRALIS readily divided through a small telescope. \u03b6 \u03b8 The modest globular NGC 6541 cluster NGC 6541 covers about one-third the TELESCOPIUM apparent diameter of a full moon. It is 19h 18h visible through a small telescope THE SOUTHERN or binoculars. CROWN","416 THE CONSTELLATIONS THE TELESCOPE were refractors with extremely long LONG VIEW 2 focal lengths\u2014to reduce chromatic Telescopium depicts an early design Telescopium aberration\u2014suspended from tall poles of refracting telescope with a long by ropes and pulleys. tube supported by a flimsy SIZE RANKING 57 mounting\u2014a far cry from the BRIGHTEST STAR SPECIFIC FEATURES massive reflectors of today. Delta (\u03b4) Telescopii is an unrelated Alpha (\u03b1) 3.5 GENITIVE Telescopii pair of stars with components of ABBREVIATION Tel 5th-magnitude. It \u02da-40 CORONA HIGHEST IN SKY AT 10 PM can be divided AUSTRALIS with binoculars July\u2013August or even SAGITTARIUS FULLY VISIBLE good eyesight. MICROSCOPIUM \u03b42\u03b41 \u03b1 \u03b5 SCORPIUS \u03b6 ARA 33\u00b0N\u201390\u00b0S \u02da-50 \u03b9 Telescopium is an almost entirely TELESCOPIUM undistinguished southern constellation near Sagittarius and Corona Australis. \u03be\u03bb It was invented by the French astronomer Nicolas Louis de Lacaille INDUS (see p.422) to commemorate the telescope. Its pattern of stars PAVO represents one of the aerial telescopes used at the Paris observatory.These THE 20h 19h TELESCOPE \u02da-60 21h 18h THE INDIAN with a spear and arrows, although it EXPLORING SPACE remains unclear whether this is Indus supposed to be a native of the East DUTCH VOYAGES OF DISCOVERY Indies (as discovered by the Dutch SIZE RANKING 49 explorers during their expeditions) As well as exploring the southern oceans, Dutch FAMILY OF EXPLORERS or a native of the Americas. BRIGHTEST STAR Alpha traders and navigators charted the southern sky. On The first Dutch expedition (\u03b1) 3.1 SPECIFIC FEATURES the first Dutch expedition to the East Indies in 1595 to the East Indies GENITIVE Indi Fifth-magnitude Epsilon (\u03b5) Indi is consisted of four ships one of the closest stars to us, being were two Dutch navigator\u2013astronomers, Pieter and was led by Cornelis ABBREVIATION Ind 11.8 light-years away. Somewhat Dirkszoon Keyser (c. 1540\u201396) and Frederick de de Houtman, the brother smaller and cooler than the Sun, it HIGHEST IN SKY AT 10 PM appears pale orange in color. Houtman (1571\u20131627). Keyser died during the voyage, of Frederick, who was on August\u2013October Theta (\u03b8) Indi is a 4th-magnitude but his celestial observations, along with those of de the trip as a navigator. star with a companion of 7th FULLY VISIBLE magnitude that can be identified Houtman, were returned to the Dutch cartographer through a small telescope. 15\u00b0N\u201390\u00b0S Petrus Plancius (see p.358 and formed the basis for 12 new constellations, all of which are still recognized. This southern constellation was CONCEALED FIGURE 2 introduced in the late 16th century Only a vivid imagination could discern the by Pieter Dirkszoon Keyser and figure of a human in the constellation of Frederick de Houtman (see panel, Indus, which comprises a few faint stars next right). It represents a human figure to the distinctive figures of Grus and Tucana. THE \u02da-40 MICROSCOPIUM INDIAN \u02da-50 GRUS T \u02da-60 INDUS \u03b6 \u03b1 \u03b4\u03b8 \u03b5 \u03b7 \u03b2 TUCANA THE NIGHT SKY PAVO \u02da-70 OCTANS HYDRUS 23h 21h 0h","MICROSCOPIUM THE CONSTELLATIONS 417 INDUS THE CRANE SCULPTOR Grus PISCIS AUSTRINUS SIZE RANKING 45 GRUS \u03bb \u03b3 BRIGHTEST STAR \u02da-40 \u03c1 \u03bc1 Alnair (\u03b1) 1.7 PHOENIX \u03b8 \u03b41 \u03bc2 GENITIVE Gruis \u03b42 ABBREVIATION Gru \u03b9\u03b2 \u03b1 HIGHEST IN SKY AT 10 PM Alnair September\u2013October FULLY VISIBLE 33\u00b0N\u201390\u00b0S \u02da-50 \u03b5 \u03b6\u03b7 Grus represents a long-necked wading bird\u2014a crane\u2014although it has also TUCANA 22h been depicted as a flamingo. It is a constellation of the southern sky and 23h is situated between Piscis Austrinus and Tucana. Grus was introduced at the end of the 16th century by the Dutch navigator\u2013astronomers Pieter Dirkszoon Keyser and Frederick de Houtman (see panel, opposite). SPECIFIC FEATURES THE CRANE Delta (\u03b4) Gruis is a pair of 4th- magnitude giants, with one yellow SHOWING THE WAY 2 Two wide doubles\u2014Delta (\u03b4) component and one red one, while and Mu (\u03bc) Gruis\u2014appear Mu (\u03bc) Gruis is a pair of 5th- along the extended neck of magnitude yellow giants. Both pairs Grus, the Crane, which points to the lower right in this image. are divisible with the naked eye. They appear double due to chance alignments and are not true binaries. Beta (\u03b2) Gruis is a red giant whose brightness ranges from magnitude 2.0 to 2.3, with no set period. THE PHOENIX MYTHS AND STORIES Phoenix MYTHICAL BIRD SIZE RANKING 37 According to legend, the phoenix was said to BRIGHTEST STAR live for 500 years. At the end of its life span, it Ankaa (\u03b1) 2.4 built a nest of cinnamon bark and incense, on GENITIVE Phoenicis which it died, some say in fire. A baby phoenix ABBREVIATION Phe was born from its ancestor\u2019s remains.The death HIGHEST IN SKY AT 10 PM and rebirth of the FUNERAL PYRE October\u2013November phoenix has been The phoenix is consumed seen as symbolic of by fire in this 18th-century FULLY VISIBLE the daily rising and German copper engraving 32\u00b0N\u201390\u00b0S setting of the Sun. from Bilderbuch f\u00fcr Kinder. PHOENIX SCULPTOR FALLING 2 Phoenix lies at the southern end of The stars of HYDRUS PHOENIX \u03b1 Ankaa \u03b9 Eridanus, next to that constellation\u2019s Phoenix sink brightest star, Achernar. It is toward the \u02da-40 \u03b3 \u03ba \u03b5 the largest of the 12 southern western horizon \u03bd \u03bc constellations introduced during in the morning \u02da-50 the late 16th century by the Dutch sky, with Grus \u03c8\u03b2 \u03bb2 navigator\u2013astronomers Pieter below it. North \u03b4 \u03bb1 Dirkszoon Keyser and Frederick de is to the right in Houtman (see panel, opposite). It this photograph. \u03b6 THE NIGHT SKY represents the mythical bird that was supposedly born from the ashes of \u03c0 its predecessor (see panel, right). \u03b7 SPECIFIC FEATURES Achernar TUCANA Zeta (\u03b6) Phoenicis is a variable double consisting of a 4th-magnitude star \u02da-60 with an 8th-magnitude companion. The brighter star is an eclipsing THE 1h 0h binary and varies between magnitudes PHOENIX 3.9 and 4.4 every 1.7 days.","418 THE CONSTELLATIONS THE TOUCAN telescope. In the entire sky, only THE SMC 215 Omega (\u03c9) Centauri is a more This neighboring mini-galaxy, the Tucana impressive globular cluster than Small Magellanic Cloud, appears 47 Tucanae. NGC 362, the other noticeably elongated. To its right in SIZE RANKING 48 globular cluster in Tucana, is smaller this image lies 47 Tucanae, or NGC and fainter and requires binoculars 104, a globular cluster in our galaxy. BRIGHTEST STAR or a small telescope to be seen. BIRD OF THE SOUTHERN SKIES 2 Alpha (\u03b1) 2.9 Beta (\u03b2) Tucanae is a naked-eye or The Toucan\u2019s huge beak points GENITIVE Tucanae binocular double with stars of 4th downward as the constellation sets and 5th magnitudes.The brighter toward the western horizon. North is ABBREVIATION Tuc component can be further separated to the right in this picture. through a telescope. Kappa (\u03ba) HIGHEST IN SKY AT 10 PM Tucanae, near NGC 362, is a double star of 5th and 7th magnitudes September\u2013November divisible through a small telescope. FULLY VISIBLE 14\u00b0N\u201390\u00b0S This far-southern constellation is to be found at the end of the celestial river, Eridanus. It represents the large- beaked tropical bird that is native to South and Central America. Tucana was introduced in the late 16th century by the Dutch navigator\u2013astronomers Pieter Dirkszoon Keyser and Frederick de Houtman (see p.416). SPECIFIC FEATURES 47 TUCANAE 215 Tucana contains the Small Magellanic This bright globular Cloud (see p.311), the lesser of the cluster looks like two satellite galaxies that accompany a fuzzy star on wide- our own galaxy.To the naked eye, it angle photographs appears like a detached patch of the like the one above Milky Way and is seven times wider right, but telescopes than the apparent diameter of a full reveal it to be an moon. Star fields and clusters within immense swarm the Small Magellanic Cloud can be of stars. detected through binoculars or a small telescope. It is about 190,000 light- THE years away. TOUCAN Two globular clusters lie near the Small Magellanic Cloud, although both are actually foreground objects in our galaxy and so are not associated with the Cloud.The more prominent of the two is 47 Tucanae (see p.294), which looks like a hazy 4th-magnitude star to the naked eye. It apparently covers the same area of sky as a full moon when viewed through binoculars or a small GRUS PHOENIX INDUS PAVO ERIDANUS \u03b3 Achernar \u03b1 \u03b2\u03bd \u02da-60 \u03b6 \u03b7 TUCANA \u03b4 \u03b5 THE NIGHT SKY \u03ba NGC 362 47 HYDRUS NGC 104 \u02da-70 SMC OCTANS 1h 0h 2h","THE CONSTELLATIONS 419 THE LITTLE WATER SNAKE SPECIFIC FEATURES HYDRUS AND ACHERNAR 2 Hydrus Pi (\u03c0) Hydri is a wide double of 6th- The sinuous little water snake winds its SIZE RANKING 61 magnitude red giants, although they way across southern skies between the two BRIGHTEST STAR lie at different distances from us and Magellanic Clouds. The brightest star near it Beta (\u03b2) 2.8 hence are unrelated. It can be split is Achernar in Eridanus (top, right.) GENITIVE Hydri ABBREVIATION Hyi readily through binoculars. HIGHEST IN SKY AT 10 PM Pi-1 (\u03c01) is of magnitude 5.6 3h 1h October\u2013December and is to be found about 740 ERIDANUS light-years away. Pi-2 (\u03c02) lies FULLY VISIBLE much closer to us, being 8\u00b0N\u201390\u00b0S about 470 light- Achernar years away; 4h it is of HOROLOGIUM \u03b1 PHOENIX magnitude 5.7. RETICULUM \u03b6 \u03c0 \u03b72 Hydrus was introduced in the \u02da-60 DORADO \u03b5\u03b4 TUCANA late 16th century by the Dutch navigator\u2013astronomers Pieter HYDRUS SMC Dirkszoon Keyser and Frederick de Houtman (see p.416). It is a \u03b3\u03bd \u03b2 constellation of the far-southern sky and is situated between the Large LMC Magellanic Cloud (see p.310) and the Small Magellanic Cloud (see p.311). \u02da-70 This constellation represents a MENSA small water snake. It should not be confused with the larger constellation THE LITTLE WATER SNAKE Hydra, also identified as a water snake, which has been recognized since the time of the ancient Greeks. THE PENDULUM CLOCK NGC 1261 is a modest globular from the Sun, being nearly 400,000 THE cluster dimly detectable through light-years away. Because it is of 16th PENDULUM Horologium a small telescope. magnitude, a large telescope is needed CLOCK to detect it. SIZE RANKING 58 Arp\u2013Madore 1 (AM1) is another FORNAX globular cluster of note within the CAELUM BRIGHTEST STAR constellation Horologium. It is the ERIDANUS most distant known globular cluster \u02da-40 _ b Alpha (\u03b1) 3.9 GENITIVE Horologii ABBREVIATION Hor HIGHEST IN SKY AT 10 PM November\u2013December FULLY VISIBLE 23\u00b0N\u201390\u00b0S AM1 PHOENIX R Horologium represents a pendulum clock, as used in observatories. Some \u02da-50 HOROLOGIUM depictions show its brightest star, Alpha (\u03b1) Horologii, marking DORADO NGC 1261 the clock\u2019s pendulum (as in the illustration here), while others include RETICULUM TW Achernar it as one of the clock weights. \u02da-60 h This faint and unremarkable i constellation of the southern sky lies ` near the foot of Eridanus and was introduced by the French astronomer \u02da-70 HYDRUS THE NIGHT SKY Nicolas Louis de Lacaille (see p.422). 5h 3h SPECIFIC FEATURES 2h R Horologii is a red-giant variable star of the same STELLAR CLOCK 2 type as Mira (in Cetus). It The shape of Horologium is ranges between 5th and reminiscent of a clock with a 14th magnitudes every long pendulum\u2014unlike many 13 months or so. of the shapeless constellations invented by de Lacaille. NGC 1261 54 The best deep-sky object in Horologium for amateur instruments is NGC 1261, a compact globular cluster of 8th magnitude more than 50,000 light-years from us.","420 THE CONSTELLATIONS THE NET 5h 4h 3h Reticulum ERIDANUS SIZE RANKING 82 HOROLOGIUM BRIGHTEST STAR \u02da-50 Alpha (\u03b1) 3.3 DORADO GENITIVE Reticuli \u02da-60 \u03b5 \u03b9 \u03b4 \u03b61,2 ABBREVIATION Ret \u03b1 \u03b3 HIGHEST IN SKY AT 10 PM December FULLY VISIBLE 23\u00b0N\u201390\u00b0S \u03b2\u03ba RETICULUM Reticulum is a small constellation LMC HYDRUS in the southern sky, near the Large Magellanic Cloud (see p.310). It was \u02da-70 THE NET introduced by the French astronomer Nicolas Louis de Lacaille (see p.422) MENSA and represents the reticule, or grid, in his eyepiece, which he used for CASTING THE NET 2 measuring star positions. This rhomboidal group of stars lies near the Large Magellanic Cloud, which is too faint to SPECIFIC FEATURES be seen here in the morning sky. The star at Zeta (\u03b6) Reticuli is a yellow double upper right is Achernar (in Eridanus). star. Its 5th-magnitude components can be split through binoculars. THE PAINTER\u2019S EASEL Pictor SIZE RANKING 59 BRIGHTEST STAR Alpha (\u03b1) 3.2 GENITIVE Pictoris ABBREVIATION Pic HIGHEST IN SKY AT 10 PM December\u2013February FULLY VISIBLE 26\u00b0N\u201390\u00b0S Pictor was invented by the French BETA PICTORIS 43 5h astronomer Nicolas Louis de Lacaille The bright areas on this professional false- (see p.422), who imagined it as an color image indicate the circumstellar disk. CAELUM artist\u2019s easel, complete with palette. Distortions in the shape may be due to a He originally called it Equuleus planetary system forming around the star. Pictoris, although that name has since been shortened. It is a faint 7h constellation of the southern sky, and it is situated beside the constellations COLUMBA Puppis and Columba. THE NIGHT SKY SPECIFIC FEATURES \u02da-40 PUPPIS PICTOR \u03b9 Beta (\u03b2) Pictoris is 63 light-years away. It is of special interest because, \u02da-50 Canopus \u03b2 DORADO in 1984, astronomers discovered a disk of dust and gas orbiting this \u02da-60 \u03b4 \u03b3 blue-white star of magnitude 3.9. The circumstellar disk is thought THE \u03b1 DIVIDING LINE 2 to be a planetary system in the PAINTER\u2019S Pictor consists of little more than a process of formation.The planets EASEL LMC RETICULUM crooked line of stars between brilliant of our solar system are believed Canopus (in Carina), seen here on the to have developed from a left, and the Large Magellanic Cloud. similar disk that existed around the Sun shortly after its formation. Iota (\u03b9) Pictoris is a double star with components of 6th-magnitude.These are readily separated through a small telescope.","THE CONSTELLATIONS 421 THE GOLDFISH SUPERNOVA 1987A 3 This supernova has faded Dorado since its dramatic flare-up in 1987. To its upper left SIZE RANKING 72 in this image is the spider- like Tarantula Nebula. BRIGHTEST STAR view through THE LMC 215 Alpha (\u03b1) 3.3 binoculars The brighter of the GENITIVE Doradus or a small telescope. two mini-galaxies that accompany our own, ABBREVIATION Dor A remarkable the Large Magellanic object in the Large Magellanic Cloud Cloud appears HIGHEST IN SKY AT 10 PM is the Tarantula Nebula, or NGC elongated in shape. It 2070. It is bright enough to be visible includes the Tarantula December\u2013January with the naked eye and can be seen Nebula (here on its well through binoculars. A cluster upper-left edge). FULLY VISIBLE of newborn stars at the heart of the Tarantula Nebula can be detected HEADING SOUTH 2 20\u00b0N\u201390\u00b0S through binoculars or a small Dorado, the Goldfish, telescope, while photographs show swims through the Dorado is one of the southern its looping extremities, like a spider\u2019s southern skies, constellations introduced in the legs, from which this large nebula apparently on its late 16th century by the Dutch of glowing gas gets its popular name. way to the south navigator\u2013astronomers Pieter celestial pole. Dirkszoon Keyser and Frederick de In February 1987 a supernova Houtman (p.416). Although known as flared up in the Large Magellanic the goldfish, Dorado in fact represents Cloud. Supernova 1987A, as it was the dolphinfish found in tropical called, reached 3rd magnitude in May waters, not common aquarium and of that year, and this made it the pond fish.The constellation has also brightest supernova visible from Earth been depicted as a swordfish. since 1604. It remained visible to the naked eye for 10 months. Most of the Large Magellanic Cloud (see p.310) is contained within Beta (\u03b2) Doradus is one of the Dorado, although this mini-galaxy brightest Cepheid variables, ranging also extends into Mensa.The first between magnitudes 3.5 and 4.1 every recorded mention of the Large 9.8 days, while R Doradus is an erratic Magellanic Cloud is credited to red giant that varies from 5th to 6th al-Sufi (see panel, below). magnitude every 11 months or so. SPECIFIC FEATURES CAELUM The Large Magellanic Cloud is a satellite galaxy of the Milky Way. It PUPPIS HOROLOGIUM is situated some 170,000 light- years away from the Earth and, at Canopus \u03b3 first sight, looks like a detached \u03b1 part of the Milky Way. Its PICTOR \u02da-50 numerous star clusters and nebulous patches are brought into CARINA \u03b6 AL-SUFI \u03b2R RETICULUM Abd al-Rahman al-Sufi (903\u201386), DORADO known also by his Latinized name, Azophi, was an Arabic astronomer. \u03b4 LMC Around AD 964, he produced the \u03b8NGC 2070 Book of the Fixed Stars\u2014an updated version of Ptolemy\u2019s Almagest\u2014 VOLANS which introduced many star names still in use today. Later editions of MENSA \u02da-70 the book contained Arabic illustrations of the constellations HYDRUS (like the one below). 6h 5h CONSTELLATION PORTRAIT 7h 4h A version of al-Sufi\u2019s Book of the Fixed Stars 8h was produced in the 16th century by a Persian artist. It included this image of Bo\u00f6tes. THE GOLDFISH THE NIGHT SKY","","","424 THE CONSTELLATIONS THE PEACOCK peacock of southeast Asia, which head and set Io free. In his memory, visibility but readily located through the Dutch explorers encountered on Hera then placed the eyes of Argus on binoculars. It covers half the apparent Pavo their travels. In more recent times, the peacock\u2019s tail. width of a full moon. A telescope its brightest star, 2nd-magnitude with an aperture of 3 in (75 mm) or SIZE RANKING 44 Alpha (\u03b1) Pavonis, was given the The constellation Pavo is to be more will resolve its brightest name Peacock. found on the edge of the Milky individual stars. BRIGHTEST STAR Way south of Sagittarius and next to In Greek mythology, the peacock another exotic bird, the toucan (the The large spiral galaxy NGC 6744 Peacock (\u03b1) 1.9 was the sacred bird of Hera, wife of constellation Tucana). is presented virtually face-on to the GENITIVE Pavonis Zeus, who traveled through the air in Earth. It is visible as an elliptical haze a chariot drawn by these birds. It was SPECIFIC FEATURES in a telescope of small to moderate ABBREVIATION Pav Hera who placed the markings on the Kappa (\u03ba) Pavonis is one of the aperture. NGC 6744 lies about tail of the peacock after an episode brighter Cepheid variables. Its 30 million light-years away. HIGHEST IN SKY AT 10 PM involving Zeus and one of his illicit fluctuations, between magnitudes loves, Io. Although Zeus had disguised 3.9 and 4.8 every 9.1 days, can be July\u2013September Io as a white cow, Hera suspected followed with the naked eye. something was amiss and set the FULLY VISIBLE 100-eyed Argus to keep watch on Xi (\u03be) Pavonis is a double star with the heifer. Her husband retaliated by components of unequal brightness\u2014 15\u00b0\u201390\u00b0S sending his son Hermes to release Io. 4th and 8th magnitudes.The fainter In order to overcome Argus, Hermes star is difficult to identify with the Pavo is one of the far-southern told him tales and played music on his smallest-aperture telescopes because constellations that were introduced at reed pipe until the watchman\u2019s eyes its brighter neighbor overwhelms it. the end of the 16th century by the closed one by one.When Argus was Dutch navigator\u2013astronomers Pieter finally asleep, Hermes chopped off his NGC 6752 is one of the largest Dirkszoon Keyser and Frederick de and brightest globular clusters in the Houtman (see p.416). It represents the sky. It is just at the limit of naked-eye NGC 6744 54 This beautiful barred spiral galaxy in Pavo is detectable through a small telescope. The Milky Way might appear like this when viewed from the outside. NGC 6752 54 The fine globular cluster NGC 6752 remains little-known because of its far-southern declination. The bright star seen above right of it in this image is a foreground object in our galaxy. 21h 20h 19h 18h SAGITTARIUS TELESCOPIUM INDUS \u03b1 NGC 6752 ARA \u03d52 \u03d51 NGC 6744 \u03bb \u03be \u03c1 \u03bd \u03c0\u03b7 \u02da\u201360 \u03b3\u03b2 \u03b4 \u03ba TRIANGULUM AUSTRALE TUCANA SX PAVO \u03b6 \u02da\u201370 \u03b5 THE NIGHT SKY OCTANS THE PEACOCK CELESTIAL DISPLAY 2 The constellation Pavo, the Peacock, is depicted fanning its tail across the southern skies, in imitation of a real-life peacock when attracting a mate.","THE CONSTELLATIONS 425 THE OCTANT changing. As a result, the south celestial pole is moving farther Octans away from Sigma and toward the constellation of Chamaeleon.There SIZE RANKING 50 are no bright stars in this area, either, so the region of the south celestial BRIGHTEST STAR pole will remain blank for another 1,500 years, when the pole will pass Nu (\u03bd) 3.8 just over a degree away from 4th- GENITIVE Octantis magnitude Delta (\u03b4) Chamaeleontis. ABBREVIATION Oct Octans represents an instrument known as an octant, which was used HIGHEST IN SKY AT 10 PM by navigators to help them find their position (see panel, right). It was October invented by the English instrument maker John Hadley (1682\u20131744). FULLY VISIBLE 0\u00b0\u201390\u00b0S This constellation, which originally SPECIFIC FEATURES SOUTHERN STAR TRAILS 2 was also known as Octans Nautica Lambda (\u03bb) Octantis is a double star Curving star trails, drawn out by the Earth\u2019s or Octans Hadleianus, contains the that is divisible with a small telescope. rotation on this long-exposure photograph, south celestial pole. It was introduced The components are of 5th and emphasize the barren nature of the area around in the 18th century by the French 7th magnitudes. the south celestial pole. astronomer Nicolas Louis de Lacaille (see p.422). 23h PAVO THE OCTANT The area of sky in which Octans 0h EXPLORING SPACE lies is quite barren.Within naked-eye range, the nearest star to the south \u02da1h \u201370 \u03bd OCTANS TRIANGULUM NAVIGATION celestial pole is Sigma (\u03c3) Octantis. AUSTRALE It is of only magnitude 5.4 and thus \u03b8 \u03b2\u03bb far from prominent. 15h HYDRUS \u02da\u201380 Because of the effect of APUS precession (see p.64), the positions of the celestial poles are constantly 14h \u03c3 \u03b4 13h \u02da3h \u201390 5h MENSA 12h In 1731, the British mathematician 11h John Hadley built a device called 6h 10h a doubly reflecting octant.The navigator sighted the horizon CHAMAELEON through a telescope and adjusted a movable arm until the reflected 7h image of the Sun or a star overlay 8h the direct view of the horizon. The altitude of the Sun or star could be read off a scale, from which the navigator could deduce his latitude. OCTANT THE NIGHT SKY This wood and brass octant is by Browning of Boston. In later designs, the arc was extended from one-eighth of a circle to one-sixth, and the octant became the modern sextant. AT THE POLE 2 Octans comprises only a scattering of faint stars. There is no bright star to mark the southern pole, which lies center left in this picture.","MO NT HLY S K Y G U I D E 426","\u201cIf the stars should appear one night in a thousand years, how would men believe and adore; and preserve for many generations the remembrance of the city of God which had been shown! But every night come out these envoys of beauty, and light the universe with their admonishing smile.\u201d Ralph Waldo Emerson AS THE EARTH MAKES its year-long journey around the Sun, the night sky changes its appearance and the stars seem to move from east to west. Depending on the observer\u2019s location, some stars are circumpolar and always visible, but others are seen only at certain times of the year. For example, some stars are seen well in the evening sky in January, but are invisible six months later, when the Earth has moved around its orbit to the opposite side of the Sun.The following section tracks seasonal changes in the night sky for observers in both the Northern and Southern hemispheres. As well as covering the regular annual cycles of the stars and constellations, it charts the positions of the planets and provides an observer\u2019s guide to celestial events, such as meteor showers and eclipses of the Sun and Moon. THE LEONID METEORS This composite image shows the Leonid meteor shower that occurs in November each year. Also visible are the Sickle, a distinctive group of stars in the constellation Leo (top left), and the planet Jupiter (center). MONTHLY SKY GUIDE","","","","JANUARY 431 SOUTHERN LATITUDES THE STARS ORION NEBULA URANUS ORION\u2019S BELT M41 is visible to the A chain of three stars forms Orion\u2019s belt, The two brightest stars in the entire naked eye as a hazy south of which can be seen the nebulosity sky, Sirius in Canis Major and patch of light, but its of M42. North is to the top of this picture. Canopus in Carina, blaze high in full complexity and the sky for southern observers this beauty are brought NEPTUNE month. Orion\u2019s brightest members, out only in long- Rigel and Betelgeuse, are also high exposure photographs 19 18 17 16 15 14 13 12 11 up, and Aldebaran, the brightest star and CCD images. in Taurus, glistens a ruddy color AQUARIUS lower in the north. Closer still to sky. M41, a large star cluster near the northern horizon, Capella is Sirius, sits on the zenith for best placed for observation on observers around 20\u00b0S. Under January evenings.The rich Milky good conditions, M41 is just Way star fields of Carina and visible to the naked eye. Centaurus lie in the southeast. By comparison, the western half of The Large Magellanic Cloud the sky appears almost barren, for (see p.310) in Dorado looks like a it contains only a scattering of stars detached scrap of the Milky Way that are easily visible to the naked lying on the meridian (an eye, the most prominent being imaginary line passing north to 1st-magnitude Achernar, in the south through the zenith) on southwest at the end of Eridanus. January evenings. Prominent among its mass of stars is the DEEP-SKY OBJECTS Tarantula Nebula, which appears to the naked eye as a glowing The Orion Nebula is ideally patch as large as a full moon.The placed for all southern observers Small Magellanic Cloud (see this month, since it is high in the p.311) in Tucana lies closer to the southwestern horizon. MIDNIGHT 9PM 19 PISCES Capella 6PM 18 17 16 15 14 13 12 CETUS Castor 3PM Pollux GEMINI TAURUS Pleiades 14 13 ARIES NOON Aldebaran Betelgeuse Hyades 12 PISCES 10\u00b0 Bellatrix 0\u00b0 Procyon 19 \u201310\u00b0 \u201320\u00b0 AQUARIUS \u201330\u00b0 \u201340\u00b0 Mira 11 17 Rigel 17 13 14 15 15 EVENING SKY 15 12 11 POSITIONS OF THE PLANETS This chart shows the positions of the planets in January from 2012 to 2019. The planets are Fomalhaut CAPRICORNUS THE NIGHT SKY represented by colored dots, while the number inside each dot denotes the year. For all planets apart from Mercury, the dot indicates the planet\u2019s position on January 15. Mercury is shown only when it is at greatest elongation (see p.68)\u2014for the specific date, refer to the table, left. Mercury Mars Saturn Neptune Venus Jupiter Uranus EXAMPLES \u201350\u00b0 16 Jupiter\u2019s position on 13 Jupiter\u2019s position on January 15, 2013. The arrow indicates January 15, 2016 that the planet is in retrograde motion (see p.68).","TRIANGULUM M34 PERSE Capella LEO M33 AURIGA MILNEOOR PISCES US LYNX WEST PEGASUS M31 NGC 869 M87 EAST 884 ANDROMEDA CASSIOPEIANGC M103 CAMELOPARDALIS UMRSAAJOR M6B4ERCEONIMCAES M81 THDEIPBPIGER CVAENNEASTICI LACERTA M52 Polaris M53 M39 CEPHEUS URSA MINOR Mizar M3 M101 M51 NORT Deneb DRACO BOOTES EAST CBOORROENAALIS HW M29 CYGNUS NORTH EST LYRA M92 M13 Vega M57 HERCULES OBSERVATION TIMES Date Standard Daylight- time saving time NORTH December 15 Midnight 1am LOOKING NORTH January 1 11pm Midnight January 15 10pm 11pm JANUARY | NOR THE R N L AT I T UD E S February 1 9pm 10pm February 15 8pm 9pm STAR MAGNITUDES DEEP-SKY OBJECTS POINTS OF REFERENCE -1 0 1 2 3 4 5 Horizons 60\u00b0N 40\u00b0N 20\u00b0N Zeniths Variable Galaxy Globular Open Diffuse Planetary 60\u00b0N 40\u00b0N 20\u00b0N Ecliptic star cluster cluster nebula nebula 432 THE NIGHT SKY","Regulus ECLIPTIC Castor GEMINI M38 PERSEUS ARIES Pollux M36 PISCES LEO A PLEIADES PYXIS M44 M37 CANCER M35 AURIGA SEXTANS M67 M1 EAST ProcyConANIS Betelgeuse A debaranHYADES TAURUS WEST NOR NOCEROS ORION HYDR I MO Be atr x Mira M S M48 CETU SCULPTOR FORNAX M50 M42 R ge ANTLIA M46 M47 Sirius LEPUS M93 MCAAJNOIRS ERIDANUS M41 Adhara PUPPIS PHOENIX CARINA W U THEAST VELA COLUMBA CAELUM HOROLOGIUM SO EST Canopus TH SOU PICTOR DORADO RETICULUM STAR MOTION North LMC SOUTH LOOKING SOUTH JANUARY | NOR TH E R N L AT I T UD E S South STAR MAGNITUDES DEEP-SKY OBJECTS POINTS OF REFERENCE -1 0 1 2 3 4 5 Horizons 60\u00b0N 40\u00b0N 20\u00b0N Zeniths Variable Galaxy Globular Open Diffuse Planetary 60\u00b0N 40\u00b0N 20\u00b0N Ecliptic star cluster cluster nebula nebula THE NIGHT SKY 433","LEPUS Sirius M47 M46 M48 ERI Rigel CANIS MAJOR M42 HYDRA CETUSDANUS M50 LEO MINOR LEO SEXTANS Mira MONOCEROS Procyon PISCES TAURUS Bellatrix M67 PEGASUS ORION CANCER WEST ECLIPTIC Betelgeuse CANIS MINOR Regulus EAST ARIES HYADES M33 TRIANGULUM Aldebaran M44 M1 Pollux Castor PLEIADES M35 M37 GEMINI PERSEUS M38 M36 ANDROMEDA AURIGA M31 R T M34 LYNX NO Capella AJOR M CASSIOPEIA NGC 869 NGC 884 URSA EAST M103 HW NORTH EST CAMELOPARDALIS DRACO M81 OBSERVATION TIMES Date Standard Daylight- time saving time NORTH December 15 Midnight 1 am LOOKING NORTH January 1 11 pm Midnight January 15 10 pm 11 pm JANUARY | S OUTHE R N L AT I T UD E S February 1 9 pm 10 pm February 15 8 pm 9 pm STAR MAGNITUDES DEEP-SKY OBJECTS POINTS OF REFERENCE -1 0 1 2 3 4 5 Variable Galaxy Globular Open Diffuse Planetary Horizons 0\u00b0 20\u00b0S 40\u00b0S Zeniths 0\u00b0 20\u00b0S 40\u00b0S Ecliptic star cluster cluster nebula nebula 434 THE NIGHT SKY","","","FEBRUARY 437 SOUTHERN LATITUDES THE STARS DEEP-SKY OBJECTS FINDING THE SOUTH CELESTIAL POLE URANUS The south celestial pole (left) is not marked by a Sirius (see p.268) and Canopus, The Milky Way, which meanders bright star, but it can be located by intersecting two the two brightest stars in the from southeast to northwest this imaginary lines. One is the extension of the long entire sky, remain high for month, contains numerous star axis of Crux. The other is at right angles to the line southern observers throughout clusters, of which M46 and M47, joining Alpha (\u03b1) and Beta (\u03b2) Centauri. February, while Achernar, the adjacent in Puppis, are prominent. 1st-magnitude star at the end of Both clusters are at the edge of the celestial river Eridanus, sinks naked-eye visibility and look toward the southwestern horizon. superb through binoculars.Two In the southeast, Crux, the other open clusters that can be Southern Cross, enters the scene, seen excellently through followed by the bright stars of binoculars are NGC 2451 and Centaurus. Higher up is the False NGC 2477, also in Puppis; farther Cross, which is formed by four south, in Vela, IC 2391 and IC stars in Vela and Carina and is 2395 are also good examples. sometimes mistaken for the true Southern Cross. Outside the boundaries of the Milky Way, the open cluster M41 Due north lie Castor (see is found south of Sirius, while in p.276) and Pollux in Gemini. the north, the Beehive Cluster (see Orion is also high in the sky, with p.290), or M44, is well positioned Taurus lower in the northwest. for observation in both February As seen from the most southerly and March. In Carina, another latitudes, Perseus has already open cluster, NGC 2516, is set and Auriga is following. prominent.The Large Magellanic Meanwhile, looking northeast, the Cloud and the Tarantula Nebula distinctive shape of Leo, the Lion, are on view, south of Canopus, has come into view. in the constellation Dorado. 19 PISCES 18 17 9PM 6PM 16 15 14 13 MIDNIGHT 12 Capella 3PM CETUS Castor NOON Pollux GEMINI Pleiades 13 ARIES 20\u00b0 14 15 Aldebaran TAURUS 12 19 Betelgeuse Hyades PISCES CANCER 17 10\u00b0 17 0\u00b0 Procyon Bellatrix \u201310\u00b0 12 AQUARIUS 19 Mira 15 13 13 15 Rigel 18 EVENING SKY \u201320\u00b0 POSITIONS OF THE PLANETS This chart shows the positions of the planets in February from 2012 to 2019. The planets are Fomalhaut \u201330\u00b0 THE NIGHT SKY represented by colored dots, while the number inside each dot denotes the year. For all planets apart from Mercury, the dot indicates the planet\u2019s position on February 15. Mercury is shown only \u201340\u00b0 when it is at greatest elongation (see p.68)\u2014for the specific date, refer to the table, left. Mercury Mars Saturn Neptune Venus Jupiter Uranus \u201350\u00b0 EXAMPLES 14 Jupiter\u2019s position on February 15, 2014. The arrow indicates that the planet is in retrograde motion (see p.68). 13 Jupiter\u2019s position on February 15, 2013","PISCES PLEIADES M38 MI LNEOOR BERCEONIMCAES ARIES CapellAa URIGA LYNX M64 M53 M81 A VECNAANTIECSI R UMRASJO WEST TRIANGULUM PER BOOTES M3 EAST THDEIPBPIEGR M33 M34 SEUS Arcturus NGC 884 CAMELOPARDALIS Mizar NGC 869 M51 M31 M103 Po ar s URSA MINOR M101 DRACO ANDROMEDA CASSIOPEIA ERALOINSA PEGASUS M52 CBOOR CEPHEUS NORT LACERTA M92 M13 EAST HW M39 HERCULES NORTH EST Deneb LYRA CYGNUS Vega M29 OBSERVATION TIMES Date Standard Daylight- time saving time NORTH January 15 Midnight 1am LOOKING NORTH February 1 11pm Midnight February 15 10pm 11pm FEBRUARY | NO R THE R N L AT I T UD ES March 1 9pm 10pm March 15 8pm 9pm STAR MAGNITUDES DEEP-SKY OBJECTS POINTS OF REFERENCE Horizons 60\u00b0N 40\u00b0N 20\u00b0N Zeniths -1 0 12 345 Variable Galaxy Globular Open Diffuse Planetary 60\u00b0N 40\u00b0N 20\u00b0N Ecliptic star cluster cluster nebula nebula 438 THE NIGHT SKY","M87 M37 M36 VIRGO Pollux Castor AURIGA M1 TAURUS Aldebaran CETUS M44 GEMINI M35 HYADES Mira LEO ECLIPTIC CRA Regulus M67 CANCER OBRellIaOtrNix WEST CORVUS Betelgeuse M104 SEXTANS Procyon MINOR EAST CANIS TER HYDRA MONOCEROS M42 Rigel DANUS HEAST M48 LEPUS ERI M46 M50 Sirius FORNAX M47 M93 M41 MAJOR PUPPIS CANIS Adhara ANTLIA COLUMBA PYXIS CAELUM T W SOU EST SOUTH VELA Canopus PICTOR DORADO CARINA STAR MOTION VOLANS North SOUTH LOOKING SOUTH FEBRUARY | NO R TH E R N L AT I T UD ES South STAR MAGNITUDES DEEP-SKY OBJECTS POINTS OF REFERENCE -1 0 1 2 3 4 5 Horizons 60\u00b0N 40\u00b0N 20\u00b0N Zeniths Variable Galaxy Globular Open Diffuse Planetary 60\u00b0N 40\u00b0N 20\u00b0N Ecliptic star cluster cluster nebula nebula THE NIGHT SKY 439","Mira CETUS Rigel LEPUS Sirius M46 ECLIPTIC PISCES M47 DRA B SEXTANS C ERI DANUS M42 M50 M48 VE VIRGO TA HY Mizar Bellatrix MONOCEROS Procyon NORTH M87 M53 WEST ORION Betelgeuse M67 EAST HYADES CANIS MINOR ARIES URUS Aldebaran M1 Regulus ERECNIOCMEAS CANCER LEO PLEIADES M64 TRIANGULUM M44 M35 GEMINI Pollux LEO MINOR Castor M37 NAATINCEIS M38 M36 LYNX AURIGA PERSEUS Capella URSA MAJOR 34 CAMELOPARDALIS TDHIEPPBEIGR EAST M RT O N HW EST M81 DRACO OBSERVATION TIMES Date Standard Daylight- time saving time NORTH January 15 Midnight 1am LOOKING NORTH February 1 11pm Midnight February 15 10pm 11pm FEBRUARY | S OUTHE R N L AT I T UD ES March 1 9pm 10pm March 15 8pm 9pm STAR MAGNITUDES DEEP-SKY OBJECTS POINTS OF REFERENCE -1 0 1 2 3 4 5 Variable Galaxy Globular Open Diffuse Planetary Horizons 0\u00b0 20\u00b0S 40\u00b0S Zeniths 0\u00b0 20\u00b0S 40\u00b0S Ecliptic star cluster cluster nebula nebula 440 THE NIGHT SKY","PYX M93 M41 AJAONIRS ANTLIA LEPUS C M HYDRA CRATER IS Adhara M104 CORVUS VIRGSpOica PUPPIS COLUMBA ERIDA NUS FOR CAELUM NAX EAST Canopus CETUS WEST M83 VELA CARINA PICTOR DORADO CENTANUGCR5U13S9 Gacrux VOLANS RETICULUM LMC Becrux CRUXAcrux MUSCA MENSA HYDRUS HOROLOGIUMAchernar IX CULPTOR Rigil Kentaurus Hadar SMC PHOEN S CHAMAELEON NGC 104 LU PUS NORMACIRCINUS TRAIUASNTGRUALLUEM STAR MOTION T HEAST TUCANA W APUS OCTANS EST North SOU GRUS TH SOU PAVO ARA INDUS SOUTH LOOKING SOUTH FEBRUARY | S OUTH E R N L AT I T UD ES South STAR MAGNITUDES DEEP-SKY OBJECTS POINTS OF REFERENCE -1 0 1 2 3 4 5 Variable Galaxy Globular Open Diffuse Planetary Horizons 0\u00b0 20\u00b0S 40\u00b0S Zeniths 0\u00b0 20\u00b0S 40\u00b0S Ecliptic star cluster cluster nebula nebula THE NIGHT SKY 441","","MARCH 443 SOUTHERN LATITUDES THE STARS DEEP-SKY OBJECTS Leo, the Lion, and its brightest star Regulus (see p.253) are high in the An open star cluster popularly northern half of the sky for all known as the Southern Pleiades, southern observers, with Castor IC 2602 lies close to the meridian (see p.276) and Pollux in Gemini on March evenings. Its brightest lower in the northwest. Sirius (see member, 3rd-magnitude Theta (\u03b8) p.268) still sparkles high in the Carinae, is easily visible to the western sky, but Orion sinks on its naked eye, and binoculars reveal at side toward the western horizon. least two dozen more members. Almost overhead for observers in mid-latitudes is Alphard, the Four degrees to the north of brightest star in the constellation the Southern Pleiades lies a large Hydra, which sprawls across an glowing region visible to the otherwise barren region of sky naked eye, NGC 3372, also known toward the southeast horizon. as the Carina Nebula (see p.247), which contains the erratic variable Spica, the brightest star in star Eta (\u03b7) Carinae (see p.262). Virgo, is well-placed in the east, Farther north, between Antlia and and Canopus, in Carina, is Vela, telescopes will pick up the prominent in the southwest sky. planetary nebula NGC 3132, also However, the main focus of known as the Eight-Burst Nebula. attention is in the southeast, where On view in the southwest sky are the Southern Cross, Crux, now the Large Magellanic Cloud and rides high along with brilliant the Tarantula Nebula (in Dorado). Alpha (\u03b1) and Beta (\u03b2) Centauri\u2014 Rigil Kentaurus (see p.252) and URANUS Hadar\u2014which point toward it. 19 PISCES 6PM 18 THE FALSE CROSS 17 Two stars in Vela (top left and center right) and two in Carina (center left 16 and bottom right) form the False Cross in the southern sky. 15 14 13 12 9PM 3PM CETUS MIDNIGHT Capella NOON GEMINI 30\u00b0 20\u00b0 Castor 10\u00b0 Pollux 0\u00b0 \u201310\u00b0 14 Pleiades ARIES 13 19 12 LEO 15 Aldebaran TAURUS 12 PISCES 12 CANCER Hyades 17 15 17 Regulus Procyon Betelgeuse 15 18 16 18 Bellatrix 12 13 Mira Rigel EVENING SKY POSITIONS OF THE PLANETS \u201320\u00b0 \u201330\u00b0 This chart shows the positions of the planets in March from 2012 to 2019. The planets are THE NIGHT SKY represented by colored dots, while the number inside each dot denotes the year. For all planets apart from Mercury, the dot indicates the planet\u2019s position on March 15. Mercury is shown only when it is at greatest elongation (see p.68)\u2014for the specific date, refer to the table, left. Mercury Mars Saturn Neptune Venus Jupiter Uranus EXAMPLES 14 Jupiter\u2019s position on March 15, 2014. The arrow indicates that the planet is in retrograde motion (see p.68). 13 Jupiter\u2019s position on March 15, 2013","Aldebaran M37 M36 M38 LYNX MAJUROSRA NES VENATICI BOOTES M3 CA HTYAADUERSUS AURIGA Arcturus M51 SERPENS CAPUT 45 Capella TDHIEPPBEIGR Mizar MPLEIADES WEST M81 101 EAST M BORCEOARLIOSNA PERSEUS TRIAN CAMELOPARDALIS URSA MINOR ARIES GULUM M34 Polaris DRACO M13 NGC 884 M92 NGC 869 HERCULES M33 M103 PISCES CASSIOPEIA M52 NORT M31 CEPHEUS Vega M57 EAST ANDROMEDA LYRA NORTH HW M39 Deneb CYGNUS EST LACERTA M29 OBSERVATION TIMES Date Standard Daylight- time saving time NORTH February 15 Midnight 1am LOOKING NORTH March 1 11pm Midnight March 15 10pm 11pm MARCH | NORTHERN LATITUDES April 1 9pm 10pm April 15 8pm 9pm STAR MAGNITUDES DEEP-SKY OBJECTS POINTS OF REFERENCE -1 0 1 2 3 4 5 Horizons 60\u00b0N 40\u00b0N 20\u00b0N Zeniths Variable Galaxy Globular Open Diffuse Planetary 60\u00b0N 40\u00b0N 20\u00b0N Ecliptic star cluster cluster nebula nebula 444 THE NIGHT SKY","VIR BCEORMENMA6IC4 ES UMRSAJO A LEO Castor M35 Bellatrix M5 LIBRA R MINOR Pollux M1 M53 EAST N ORIO M87 LEO M44 GEMINI ERIDANUS PMroCcOAyoNNnOISCEMRINOSOR Betelgeuse GO Regulus CANCER WEST M50 M67 Sirius M42 ECLIPTIC CAAdhNarIaSM4M1 AJOR Rigel Spica LEPUS M104 SEXTANS M48 HYDRA CRATER M47 CORVUS M46 M M93 83 PYXIS ANTLIA LUMBA VELA CO VOLANS PUPPIS U NGC CENTAURUS CARINA W SO 5139 EST THEAST Canopus TH SOU Gacrux CRUX STAR MOTION North SOUTH LOOKING SOUTH MARCH | NORTHERN LATITUDES South STAR MAGNITUDES DEEP-SKY OBJECTS POINTS OF REFERENCE -1 0 1 2 3 4 5 Horizons 60\u00b0N 40\u00b0N 20\u00b0N Zeniths Variable Galaxy Globular Open Diffuse Planetary 60\u00b0N 40\u00b0N 20\u00b0N Ecliptic star cluster cluster nebula nebula THE NIGHT SKY 445","ERIDANUS M42 M46 CRATER Spica Rigel M47 M104 M50 MONOCER M5 Betelgeuse M48 SEXTANS ECLIPTIC VIRGO EAST WEST Aldebaran ORION OS Procyon HYDRA Regulus RECNIOCMEAS M87 MICNAONRIS HYADETSAURUS Bellatrix M67 LEO M53 M3 CANCER Arcturus 1 M PLEIADES M35 GEMINI M44 M64 Pollux BE PERSEU M36 M37 Castor LEO MINOR S AURIGAM38 URSA MAJOR VENATICI BOOTES LYNX TDHIEPPBEIGR CANES M51 Capella M81 Mizar M101 NORT CAMELOPARDALIS AST NORTHE HW EST DRACO OBSERVATION TIMES Date Standard Daylight- time saving time NORTH February 15 Midnight 1am LOOKING NORTH March 1 11pm Midnight March 15 10pm 11pm MARCH | SOUTHERN LATITUDES April 1 9pm 10pm April 15 8pm 9pm STAR MAGNITUDES DEEP-SKY OBJECTS POINTS OF REFERENCE -1 0 1 2 3 4 5 Variable Galaxy Globular Open Diffuse Planetary Horizons 0\u00b0 20\u00b0S 40\u00b0S Zeniths 0\u00b0 20\u00b0S 40\u00b0S Ecliptic star cluster cluster nebula nebula 446 THE NIGHT SKY","VIRGO CORVUS M93 Adhara PYXIS LEPUS M M41 ERIDANUS ANTLIA AJOR Sirius HYDRA CANIS CE EAST LIBRA WEST 83 M NTAURUS VELA PUPPIS BA COLUM Canopus NGC 5139 Gacrux CARINA CAEL UM LU PUS FORNAX Becrux Acrux PICTOR DORADO M4 Shaula M80 Antares CRUX MUSCA HEAST Rigil Kentaurus Hadar RETICULUM SMC6O2 RPIUS NORMA CIRCINUS VOLANS LMC HOROLOGIUM APUS MENSA CHAMAELEON ARA TARUIASNTRGAULLEUM HYDRUS Achernar SMC T PAVO OCTANS NGC 104 PHOENIX W SOU EST TUCANA SOUTH TELESCOPIUM STAR MOTION North INDUS SOUTH LOOKING SOUTH MARCH | SOUTHERN LATITUDES South STAR MAGNITUDES DEEP-SKY OBJECTS POINTS OF REFERENCE -1 0 1 2 3 4 5 Variable Galaxy Globular Open Diffuse Planetary Horizons 0\u00b0 20\u00b0S 40\u00b0S Zeniths 0\u00b0 20\u00b0S 40\u00b0S Ecliptic star cluster cluster nebula nebula THE NIGHT SKY 447",""]