The constellations in tonight’s sky host many familiar star patterns. For northern observers, winter is the best time of the year to see Auriga (the Charioteer) and Gemini (the Twins). These constellations appear high overhead in the evening.
Observers in the southern hemisphere can catch Canis Major (the Great Dog), Columba (the Dove), Lepus (the Hare), and Puppis (the Stern) high in the evening sky at this time of the year. These constellations are relatively bright and easy to see even from areas with some light pollution.
The night sky tonight looks different depending on the location. The constellation maps below show the sky as it appears at around 10 pm in the mid-northern, equatorial, and mid-southern latitudes.
Northern hemisphere
Auriga (the Charioteer) and Gemini (the Twins) are the brightest constellations appearing high overhead in the evening for observers in the northern latitudes. Lynx occupies much of the space between these two constellations and Ursa Major (the Great Bear), but its brightest stars are fainter than magnitude 3.0 and difficult to see from urban skies.
Auriga’s hexagon is the most prominent feature of the Charioteer constellation. Formed by Capella, Menkalinan, Almaaz, Mahasim, and Hassaleh in Auriga with Elnath in Taurus, the hexagon pattern is a guide to several relatively bright deep sky objects that appear in this area of the sky. These include the bright open clusters Messier 36, Messier 37, and Messier 38, the Flaming Star Nebula (IC 405), the Tadpole Nebula (IC 410), the Spider Nebula (IC 417), and the Fly Nebula (NGC 1931).
Tonight’s sky as seen from mid-northern latitudes, image: Stellarium
Capella, the brightest star in Auriga, is the sixth brightest star in the sky. It is traditionally known as the Goat Star. Two relatively bright stars near it, Saclateni and Haedus (Zeta and Eta Aurigae), represent the Goat’s kids (Haedi). Almaaz (Epsilon Aurigae) at the Charioteer’s elbow is often included in the Kids asterism but was historically not part of it.
Gemini appears southeast of Auriga and northeast of the bright Orion (the Hunter). Pollux and Castor, the constellation’s brightest stars, represent the heads of the celestial Twins. Pollux is the 17th brightest star in the sky and Castor is the 23rd.
Pollux is part of the Winter Circle, a large asterism that dominates the northern winter sky. Also known as the Winter Hexagon, the asterism appears high in the southwestern sky in the evening. The other five stars of the Winter Circle are Capella in Auriga, Aldebaran in Taurus, Rigel in Orion, Sirius in Canis Major, and Procyon in Canis Minor.
Eastern sky
The zodiac constellations Leo (the Lion) and Virgo (the Maiden) rise in the east in the evening. The fainter Coma Berenices (Berenice’s Hair) and Canes Venatici (the Hunting Dogs) appear in the region between Virgo and the handle of the Big Dipper.
Leo is one of the most identifiable constellations in the sky. It looks exactly like the animal it represents. The Lion’s mane is outlined by an asterism known as the Sickle of Leo. The bright Regulus, the star marking the Lion’s heart, appears at the base of the Sickle. Denebola appears at the tip of the Lion’s tail.
The Lion’s tail once extended into what is now Coma Berenices. The stars of Berenice’s Hair represented the tuft of the tail.
Eastern sky in the northern hemisphere, image: Stellarium
The stars of Coma Berenices are faint. The constellation’s luminaries, the yellow dwarf Beta Comae Berenices and yellow-white dwarf Diadem (Alpha Comae Berenices) shine at magnitudes 4.26 and 4.32.
However, the constellation is easy to spot because it contains an exceptionally bright and large open cluster, the Coma Star Cluster (Melotte 111). The cluster is easily visible on a clear night. It has an apparent magnitude of 1.8 and stretches across 7.5 degrees of the sky. It lies only 280 light-years away.
Coma Berenices hosts the Coma Cluster of galaxies, a large cluster that contains more than 1,000 members. The constellation is also home to a portion of the Virgo Cluster, a galaxy cluster that occupies about 8 degrees of the sky and is centred in the neighbouring zodiac constellation Virgo.
The Y of Virgo, the identifying feature of Virgo, has partly risen by 10 pm, but the bright Spica, the 16th brightest star in the sky, rises a bit later in the evening. Spica appears at the base of the crooked Y asterism and can be found by following the arc of the Big Dipper’s handle. The curved line extended from Alioth, Mizar and Alkaid first leads to Arcturus, the brightest northern star, and then to Spica.
Arcturus is the brightest star in the constellation Boötes (the Herdsman), which appears in the northeastern sky in the evening. The orange giant is the fourth brightest star in the sky. It lies at the base of an asterism called the Kite.
Arcturus, Spica, and Regulus form the Spring Triangle, an asterism that dominates the northern spring sky. As the spring season approaches, the asterism will keep rising a little earlier in the sky until it is fully visible around 10 pm.
Arcturus and Spica are also part of the Great Diamond (or the Diamond of Virgo), an asterism also formed by Cor Caroli in the constellation Canes Venatici (the Hunting Dogs) and Denebola in Leo.
Northern sky
The constellations that appear in the northern sky are mostly those that are circumpolar to the northern hemisphere: Ursa Minor (the Little Bear), Cepheus (the King), and Draco (the Dragon). Cassiopeia (the Queen) lies in the northwestern sky and Ursa Major (the Great Bear) is high in the northeast. At this time of the year, the Big Dipper appears upside down, with the handle pointing toward the horizon in the evening.
Polaris, the brightest star in Ursa Minor, marks the location of the north celestial pole. The North Star lies at the tip of the Little Bear’s tail and at the end of the Little Dipper’s handle. It can be found using the outer stars of the Big Dipper’s bowl. A line extended from Merak through Dubhe points in the general direction of Polaris.
Northern sky in the northern hemisphere, image: Stellarium
Draco, one of the largest constellations in the sky, winds around the bowl of the Little Dipper. The Dragon’s tail is found between the Big and Little Dippers. Its head appears close to the northern horizon in the evening. The Head of Draco is outlined by four relatively bright stars: Eltanin, Rastaban, Grumium, and Kuma. Eltanin and Rastaban, the stars that represent the Dragon’s eyes, appear closer to the horizon.
The dominant constellation figure of Cepheus – a stick house – can be made out near Cassiopeia on a clear, dark night. Alderamin, the brightest star in Cepheus, appears at the base of the house asterism. It can be found by extending a line from Schedar through Caph. The bright stars of Cassiopeia’s W appear in the northwestern sky.
Western sky
Cetus (the Sea Monster) and Aries (the Ram) set in the west around 10 pm and the more prominent Orion (the Hunter), Taurus (the Bull), and Perseus are still high above the western horizon. The Head of Cetus appears almost directly west while Aries lies more to the northwest. The bright Menkar, the star that marks the Sea Monster’s jaw, can be found by following the V of the Hyades cluster in Taurus.
The Hyades and the Pleiades are among the brightest and nearest open clusters in the sky. The more conspicuous Pleiades cluster marks the shoulder of Taurus while the V-shaped Hyades marks the Bull’s Head.
Aldebaran, the brightest star in Taurus and the 14th brightest star in the sky, appears in the same line of sight as the Hyades but is not a member of the cluster. It lies much closer to us and marks one of the Bull’s eyes.
Western sky in the northern hemisphere, image: Stellarium
Aldebaran can be found using the stars of Orion’s Belt, one of the most recognizable asterisms in the night sky. Alnitak, Alnilam, and Mintaka point in the direction of the giant star. In the opposite direction, they point towards Sirius in Canis Major, the brightest star in the sky.
Orion appears high in the northwestern sky. Its main constellation figure – a crooked hourglass – is outlined by Betelgeuse, Rigel, Bellatrix, Saiph, and the stars of Orion’s Belt. Rigel, the constellation’s brightest star, can be used to find Cursa, the second brightest star in Eridanus (the River).
Most northern observers cannot see the entire constellation Eridanus at any time of the year, but a good portion of it is now visible above the southwestern horizon in the evening. The celestial River stretches farther from north to south than any other constellation. Its northern end appears near Rigel and its southern end lies in the far southern sky. It is marked by Achernar, the ninth brightest star in the sky.
Perseus sits high in the southwest. Its stars are easily visible between Taurus and Cassiopeia on a clear night. The supergiant Mirfak, the constellation’s brightest star, is the brightest member of the Alpha Persei Cluster, an open cluster visible to the unaided eye in good conditions.
Aries (the Ram) and Triangulum (the Triangle) appear between Perseus and the horizon, while the larger Pisces (the Fishes) has mostly set by 10 pm.
The brightest stars of Andromeda (the Princess) – Alpheratz, Mirach, and Almach – form a chain that appears almost perpendicular to the northwestern horizon in the evening.
Southern sky
The constellations of the Winter Circle dominate the southern and southwestern evening sky.
Sirius, the brightest star in the sky, is high above the southern horizon. The stars that mark the Great Dog’s hind legs and tail – Adhara, Wezen, and Aludra – form a triangle that appears below the bright Dog Star.
Procyon, the brightest star in Canis Minor and the eighth brightest star in the sky, appears higher above the horizon, almost directly south.
Southern sky from the northern hemisphere, image: Stellarium
The two dog constellations – Canis Major and Canis Minor – represent the dogs following Orion, the Hunter, as he chases a hare represented by the constellation Lepus. Orion and Lepus appear in the southwest. The ears of the Hare lie just below Rigel and its tail is found below Saiph, pointing in the direction of Sirius.
Sirius and Procyon form the Winter Triangle with Betelgeuse at Orion’s shoulder. The bright asterism can be used to locate the faint Monoceros (the Unicorn).
The stars of Monoceros are invisible from heavily light-polluted areas, but the constellation is a popular target for stargazers and astrophotographers because it hosts several well-known deep-sky objects. These include the Rosette Nebula with the Satellite Cluster, the Cone Nebula with the Christmas Tree Cluster, and the open cluster Messier 50.
Puppis makes an appearance directly south, but it stays low above the horizon for most northern observers. Representing the stern of Argo, the mythical ship of Jason and the Argonauts, Puppis once formed the larger constellation Argo Navis with the neighbouring constellations Carina (the Keel) and Vela (the Sails).
Puppis is the largest and northernmost of the three constellations. It hosts three open clusters listed in the Messier catalogue: Messier 46, Messier 47, and Messier 93.
Hydra (the Water Snake), the largest of the 88 constellations, appears in the southeastern sky. The constellation is relatively faint, but its luminary Alphard can be found using the brighter stars of Leo. The head of Hydra can be made out between Procyon and Regulus on a clear, dark night.
The faint constellations Pyxis (the Compass) and Antlia (the Air Pump) also make an appearance in the southern and southeastern sky, but their stars are barely visible from light-polluted areas. Alpha Pyxidis shines at magnitude 3.68 and Alpha Antliae is even fainter at magnitude 4.25.
Equatorial latitudes
The most conspicuous constellations high overhead in the evening are Canis Major (the Great Dog) and Canis Minor (the Lesser Dog). Canis Major hosts Sirius, the brightest star in Earth’s sky, and Canis Minor is home to Procyon, the eighth brightest star.
Canis Major and Canis Minor can be used to find the faint Monoceros (the Unicorn), which lies in the region between the dog constellations and Orion (the Hunter).
The head of Hydra (the Water Snake), the largest constellation in the sky, appears near the zenith around 10 pm. While the stars of Hydra are mostly faint, the mythical monster’s head can be found between Procyon and Regulus, the brightest star in Leo (the Lion).
Tonight’s sky as seen from equatorial latitudes, image: Stellarium
Northern sky
The bright Gemini (the Twins) appears high above the northern horizon. Its brightest stars, Pollux and Castor, represent the heads of the celestial Twins. Pollux can be used to find the fainter Cancer (the Crab), which appears between it and Regulus in Leo.
The faint Lynx appears directly north, high above the horizon, but is a challenging target in light-polluted skies. Its brightest star, the orange giant Alpha Lyncis, shines at magnitude 3.14.
Camelopardalis (the Giraffe), which appears close to the horizon, is even fainter. The yellow supergiant/bright giant Beta Camelopardalis, the constellation’s brightest star, has an apparent magnitude of 4.02.
Northern sky from equatorial latitudes, image: Stellarium
The bright Auriga (the Charioteer) is high in the northwestern sky. Home to Capella, the sixth brightest star in the sky, the constellation is easy to identify. Its five brightest stars form a prominent hexagon with Elnath, the star that marks the northern horn of Taurus, the Bull.
Ursa Major (the Great Bear) stretches from the northern into the northeastern sky. The Big Dipper appears upside down and Alkaid at the end of the Dipper’s handle may or may not be visible, depending on the geography.
Ursa Major can be used to find Lynx, which lies between the Big Dipper and the Twins, and the equally faint Leo Minor (the Little Lion), which appears between the Great Bear’s front legs and the Lion’s mane.
Eastern sky
The zodiac constellations Leo (the Lion) and Virgo (the Maiden) easily stand out above the eastern horizon. The Lion’s tail, marked by the bright Denebola, is pointing toward the horizon, and its head and mane appear higher in the sky. They are outlined by an asterism called the Sickle. The Sickle looks like a backward question mark and has Regulus, the constellation’s brightest star, at its base.
Virgo, the second largest constellation in the sky, has mostly risen by 10 pm. Its luminary Spica appears low in the sky and sits at the base of the Y of Virgo, a bright asterism that looks like a crooked letter Y and makes the constellation recognizable.
Eastern sky from equatorial latitudes, image: Stellarium
Spica can be used to find the constellation Corvus (the Raven). The brightest stars of Corvus form an asterism known as Spica’s Spanker or the Sail. The northern side of the asterism points in the direction of Spica. The fainter Crater (the Cup) appears above Corvus but is not an easy target from urban areas.
The same can be said for Hydra. Even though it is the largest of all constellations, the Water Snake constellation does not contain many bright stars. Its luminary Alphard, an orange giant, shines at magnitude 2.00 and the constellation’s second brightest star, the yellow giant Gamma Hydrae, is a full magnitude fainter.
Sextans (the Sextant), one of the faintest constellations in the sky, appears directly east, between Leo and Hydra. Its brightest star, the white giant Alpha Sextantis, is difficult to make out even in good conditions. It shines at magnitude 4.49.
Western sky
The constellations that set in the west in the evening include Cetus (the Sea Monster) and Eridanus (the River).
Cetus has partly set by 10 pm. The head of the Sea Monster hovers low above the horizon. It is formed by a circle of mostly faint stars. Menkar, the star marking the Sea Monster’s jaw, can be found using the V-shaped head of the Bull as a pointer.
Eridanus, the celestial River, occupies much of the western and southwestern sky. Achernar, the first-magnitude star that marks the River’s end, is below the horizon. The constellation’s second brightest star, Cursa, appears near Rigel at Orion’s foot.
Taurus is high above the horizon in the evening. Aldebaran, the brightest star in the constellation, is found along the imaginary line extended from Alnitak, Alnilam, and Mintaka, the stars of Orion’s Belt, to the northwest.
Western sky from equatorial latitudes, image: Stellarium
Aldebaran appears as the brightest member of the Hyades, a bright, large, V-shaped open cluster easily visible to the unaided eye. However, the giant star is not really a member of the cluster. It lies 65.3 light-years away, while the cluster is about 153 light-years away.
The Pleiades cluster appears lower in the sky, near the border with Perseus. The cluster marks the Bull’s shoulder and is one of the most recognizable features of the northern sky. It appears as a bright bunch of grapes and is easily visible to the unaided eye even from light-polluted areas. The star cluster is best viewed with binoculars.
Elnath, the second brightest star in Taurus, marks the Bull’s northern horn and is part of Auriga’s hexagon. Tianguan, the star that marks the southern horn, lies in the region between Elnath and Betelgeuse. It can be used to find the famous Crab Nebula (Messier 1), the remnant of a historic supernova seen in 1054.
The hourglass figure of Orion appears parallel to the horizon. The Hunter’s shoulders are marked by the bright Betelgeuse and Bellatrix and his feet by Saiph and Rigel. The Belt of Orion, one of the best-known asterisms in the sky, is formed by the hot blue stars Alnitak, Alnilam and Mintaka.
Orion’s Sword, seen hanging from the Hunter’s belt, is another recognizable asterism in the constellation. The point of light in the middle of the Sword is the Orion Nebula (Messier 42), the nearest massive star-forming region to the Sun. The nebula is visible to the unaided eye even in less-than-ideal conditions.
Lepus (the Hare) appears at Orion’s feet. Representing a hare chased by Orion and his two dogs – Canis Major and Canis Minor – Lepus has a distinctively rabbit-like pattern. Its ears lie near Rigel and its tail is near Saiph.
Perseus appears between Auriga and the northwestern horizon. The supergiant Mirfak, the brightest star in Perseus, is the central star in the bright Alpha Persei Cluster, another open cluster visible to the unaided eye. The star and the cluster are part of the Segment of Perseus, an asterism formed by a curving line of stars between Cassiopeia and Auriga.
Southern sky
The three constellations that once formed Argo Navis, the largest constellation in the sky, appear high above the southern horizon in the evening. Puppis, the northernmost of the three, represents the stern of the mythical ship Argo, on which Jason and the Argonauts set off on their quest to get the Golden Fleece. Vela represents the ship’s sails and Carina, the keel.
Naos, the brightest star in Puppis, is one of the most luminous stars known. It is 813,000 times more luminous than the Sun and shines at magnitude that varies from 2.24 to 2.26 from a distance of 1,080 light-years. With a mass 56.1 times that of the Sun, the hot blue O-type supergiant is a supernova candidate. Even though its age is only 3.2 million years (compared to the Sun’s 4.6 billion years), Naos is already near the end of its life.
Southern sky from equatorial latitudes, image: Stellarium
Regor, the luminary of Vela, is part of a multiple-star system that contains the brightest and nearest Wolf-Rayet star to the Sun. The star has a mass 9 times that of the Sun and is 170,000 times more luminous. It has a close spectroscopic companion, a hot blue O-type giant with a mass of 28.5 solar masses and a luminosity of 280,000 Suns.
Canopus, the brightest star in Carina, is the second-brightest star in the sky, after Sirius. The white bright giant star shines at magnitude -0.74 from a distance of 310 light-years.
Carina also hosts Eta Carinae, one of the most luminous stars known. Shrouded in the Homunculus Nebula, within the larger Carina Nebula, Eta Carinae is believed to be a binary star with a combined luminosity about 4.6 million times that of the Sun. The primary component is about 100 times more massive than the Sun, while the secondary has a mass between 30 and 80 times that of the Sun.
The Carina Nebula is a giant stellar nursery located about 7,500 light-years away and visible to the unaided eye. It has an apparent magnitude of 1.0 and an apparent size of 120 arcminutes. It hosts some of the most massive and luminous stars known in the Milky Way.
Miaplacidus, the second brightest star in Carina, can be used to find the fainter constellations Volans (the Flying Fish) and Chamaeleon, while Canopus appears near the border with Pictor (the Easel).
The faint Dorado (the Dolphinfish) and Mensa (Table Mountain) host the Large Magellanic Cloud (LMC), a Milky way satellite located only 163,000 light-years away. The dwarf galaxy is visible without binoculars and appears as a detached piece of the Milky Way in the sky.
Its smaller sibling, the Small Magellanic Cloud (SMC), lies in the constellations Hydrus (the Lesser Water Snake) and Tucana (the Toucan) and stays below the horizon in the evening.
Crux, the most identifiable constellation in the far southern sky, appears low above the southeastern horizon. Its brightest stars – Acrux, Mimosa, Gacrux, Imai, and Ginan – form the Southern Cross, an asterism found on many national flags in the southern hemisphere.
The stars of Crux can be used to find the fainter Musca (the Fly). Crux, Musca, and Centaurus are home to the Coalsack Nebula, the most prominent dark nebula in the sky. The nebula spans an area of 7 by 5 degrees and is easily spotted near the Southern Cross.
Southern hemisphere
The brightest constellations that appear high overhead around 10 pm are Canis Major (the Great Dog) and Puppis (the Stern). The fainter Lepus (the Hare) and Columba (the Dove) are also easily spotted, while the stars of Caelum (the Chisel) are a more difficult target.
Canis Major is home to Sirius, the brightest star in the sky and one of our nearest neighbours. The Dog Star shines at magnitude -1.46 from a distance of only 8.60 light-years. It marks the Great Dog’s neck. The three relatively bright stars that outline the Dog’s hind legs and tail – Adhara, Wezen, and Aludra – form a distinctive triangle below Sirius.
Puppis, the southern constellation that represents the stern of the mythical ship Argo, lies near the Great Dog’s tail. Its two brightest stars, Naos and Pi Puppis, are exceptionally luminous supergiants located at great distances.
Naos is one of the most luminous stars visible to the unaided eye. The O-type supergiant shines at magnitude 2.24 from 1,080 light-years away and Pi Puppis, an orange supergiant, has an apparent magnitude of 2.73 and lies 810 light-years away.
Tonight’s sky as seen from the southern hemisphere, image: Stellarium
Puppis hosts three bright open clusters catalogued by Charles Messier: Messier 46, Messier 47, and Messier 93. The clusters appear in the same area of the sky as Sirius.
Lepus represents a hare chased by Orion and his two dogs, Canis Major and Canis Minor. While the constellation is not particularly conspicuous, it is easy to identify because it looks like the animal that it represents. It lies near the bright Orion stars Rigel and Saiph.
Columba is a small constellation appearing south of Canis Major and Lepus. Unlike Puppis, Lepus, and the dog constellations, the celestial Dove does not date to ancient times. It was created by the Dutch-Flemish astronomer Petrus Plancius in the late 16th century. The constellation represents Noah’s Dove.
Northern sky
Five first-magnitude stars appear in the northern sky in the evening: Rigel and Betelgeuse in Orion (the Hunter), Procyon in Canis Minor (the Little Dog), Pollux in Gemini (the Twins), and Aldebaran in Taurus (the Bull).
The constellation figure of Orion appears upside down. It is formed by Rigel, Betelgeuse, Bellatrix, Saiph, and the stars of Orion’s Belt (Alnitak, Alnilam, and Mintaka). A line extended from Rigel through Betelgeuse points in the general direction of Castor in Gemini.
Castor and the slightly brighter Pollux represent the heads of the mythical Twins. Pollux is one of the stars that form what is known as the Winter Hexagon in the northern hemisphere. The Winter Hexagon is an exceptionally bright and large asterism formed by six first-magnitude stars (Sirius, Capella, Rigel, Procyon, Aldebaran, and Pollux). While the bright Capella in the constellation Auriga (the Charioteer) stays below the horizon for most observers in the mid-southern latitudes, the other five stars appear high in the evening sky.
Northern sky in the southern hemisphere, image: Stellarium
A smaller hexagonal asterism appears low above the northern horizon. Formed by the brightest stars of Auriga with Elnath in Taurus, Auriga’s hexagon can be used to find several star-forming regions that lie within its borders. These include the Flaming Star Nebula and the Tadpole Nebula. The stars of Auriga’s hexagon can also be used to find the bright Messier clusters M36, M37, and M38.
Procyon, the brightest star in Canis Minor, is the eighth brightest star in the sky. Like Sirius, Procyon appears so bright because it is one of the Sun’s nearest neighbours. The star lies only 11.46 light-years away.
Procyon, Sirius, and Betelgeuse can be used to find the faint Monoceros. The Unicorn constellation lies within the triangle formed by the three stars. In the northern hemisphere, the triangle asterism is known as the Winter Triangle or the Great Southern Triangle.
Eastern sky
Hydra (the Water Snake), the largest of the 88 constellations, stretches from the northeastern to the southeastern sky. Despite its size, the constellation does not stand out in the sky because its stars are mostly faint. The giant Alphard, the constellation’s brightest star, shines at magnitude 2.0. It can be identified using the stars of the Sickle of Leo. Gamma Hydrae, the second brightest star in Hydra, is considerably fainter.
Spica, the luminary of Virgo, has not yet risen around 10 pm, but Spica’s Spanker, an asterism formed by the brightest stars of Corvus (the Raven), is easy to spot above the eastern horizon. The four stars that form it – Gienah, Kraz, Algorab, and Minkar – shine at magnitudes 2.6 – 3.0. Gienah and Algorab point in the direction of Spica.
Eastern sky in the southern hemisphere, image: Stellarium
The asterism is also known as the Sail. It can be used to find the famous Sombrero Galaxy (Messier 104) in Virgo and the interacting pair NGC 4038 and NGC 4039, also known as the Antennae Galaxies, in Corvus.
The faint constellations Crater (the Cup) and Sextans (the Sextant) are challenging targets even in good conditions. The giant Delta Crateris, the only star in Crater that is brighter than magnitude 4.0, shines at magnitude 3.56. Alpha Sextantis, the luminary of Sextans, has an apparent magnitude of 4.5, and other stars in the constellation are fainter than magnitude 5.0.
Antlia (the Air Pump) appears higher in the sky, on the other side of Hydra, but it is just as faint. Its three brightest stars, the orange giants Alpha, Epsilon, and Iota Antliae, have apparent magnitudes of 4.25, 4,51, and 4.60.
Leo rises in the northeastern sky. The constellation figure of the Lion is mostly visible by 10 pm. The Sickle, formed by Regulus with several other relatively bright stars, forms the Lion’s head and mane. Regulus marks the Lion’s heart and Denebola, which rises a bit later in the evening, marks the Lion’s tail.
Western sky
Cetus (the Sea Monster) and Eridanus (the River) take up much of the western sky in the evening. Even though they each contain several stars brighter than magnitude 3.0, the constellations do not contain any particularly conspicuous asterisms that would make them instantly recognizable.
The Head of Cetus, an asterism formed by the bright Menkar (mag. 2.53) with several fainter stars, can be found using the V-shaped Hyades cluster, which outlines the head of the Bull (Taurus). The V of the Hyades points towards Menkar.
The brighter Diphda (mag. 2.02) appears lower in the sky. It marks the tail of Cetus. The famous variable red giant Mira appears in the Sea Monster’s neck. It has been observed to outshine Diphda but is normally much fainter.
Western sky in the southern hemisphere, image: Stellarium
Eridanus stretches from Rigel in Orion near the celestial equator into the far southern sky. The hot blue star Achernar, the brightest star in Eridanus, is the ninth-brightest star in the sky. It is the brightest star above the southwestern horizon in the evening. It marks the River’s end. The faint Fornax (the Furnace) can be made out in the bend of the River on a clear, dark night.
Taurus dominates the northwestern sky. The constellation’s brightest star, the giant Aldebaran, is the 14th brightest star in the sky. It appears in the same line of sight as the Hyades and can be found on the imaginary line extended from the three stars of Orion’s Belt. The more conspicuous Pleiades cluster (Messier 42) appears directly below Aldebaran and the Hyades in the evening.
Aries (the Ram) sets in the northwest around 10 pm. Its three brightest stars, Hamal, Sheratan, and Mesarthim, form a flat triangle that makes the constellation identifiable.
The Southern Birds constellations Phoenix, Tucana (the Toucan), and Grus (the Crane) appear in the southwestern sky. Phoenix is found below Achernar, and Grus appears low above the southwestern horizon.
The faint Sculptor, the home of the Sculptor Galaxy (NGC 253) and the Cartwheel Galaxy (ESO 350-40), is difficult to see from light-polluted areas. The constellation can be found within the triangle formed by Diphda, Alnair, and Ankaa, the brightest stars in Cetus, Grus, and Phoenix.
Southern sky
The most conspicuous constellation above the southern horizon is Triangulum Australe (the Southern Triangle). Its three brightest stars – Atria (Alpha Trianguli Australis), Beta Trianguli Australis, and Gamma Trianguli Australis – form an almost equilateral triangle that appears just to the right of the Southern Pointers in the evening.
Atria, the brightest of the three stars, points in the direction of Pavo (the Peacock). Peacock (Alpha Pavonis), the brightest star in Pavo, is one of the bright stars selected for use in celestial navigation, but the rest of the constellation is relatively inconspicuous.
Triangulum Australe and the Southern Pointers can be used to find Circinus (the Compass). The constellation figure of Circinus, a small, elongated triangle reminiscent of the compass (the drafting tool), can be made out between the Southern Triangle and the luminaries of the constellation Centaurus (the Centaur).
Southern sky in the southern hemisphere, image: Stellarium
The Southern Pointers – Alpha and Beta Centauri (Rigil Kentaurus and Hadar) – appear in the southeastern sky. They are called the Pointers because they point towards the Southern Cross, an asterism commonly used to find true south.
Alpha Centauri is the nearest star system to the Sun and the third brightest star in the sky. The star system contains Proxima Centauri, the closest individual star to the Sun. The red dwarf lies only 4.2465 light-years away, while the system’s brighter components, Rigil Kentaurus and Toliman, lie 4.344 light-years away.
Hadar (Beta Centauri) is much more distant and intrinsically luminous. It shines at magnitude 0.61 from a distance of 390 light-years. It is an evolved hot blue giant star about 66,000 times more luminous than the Sun.
The celestial Centaur appears upside down above the southeastern horizon in the evening. The orange giant Menkent, the third brightest point of light in Centaurus, marks the Centaur’s head while Alpha and Beta Centauri mark its feet.
The constellation Lupus (the Wolf) is partly visible below the Pointers. Its brightest star, the hot blue giant Uridim (Alpha Lupi), shines at magnitude 2.30 from a distance of 460 light-years.
The bright Crux hosts the Southern Cross, the best-known asterism in the southern hemisphere. Largely unknown to northern observers due to its location in the far southern sky, the Southern Cross is formed by Acrux (Alpha Crucis), Mimosa (Beta Crucis), Gacrux (Gamma Crucis), and Imai (Epsilon Crucis). A line extended from Gacrux through Acrux points in the general direction of the south celestial pole.
The southern celestial pole lies in the faint constellation Octans (the Octant). The South Star, Sigma Octantis (Polaris Australis), is barely visible even in the best of conditions, so the bright stars of Crux, Centaurus, and Eridanus are commonly used to determine the location of the pole. Polaris Australis lies roughly halfway between Hadar in Centaurus and Achernar in Eridanus.
Crux stars can be used to find the fainter Musca (the Fly), which lies near Acrux. Created in the late 16th century, Musca is one of the constellations named after the animals that Dutch explorers encountered on their journeys in the southern hemisphere. Apus (the Bird-of-Paradise), Chamaeleon, Pavo (the Peacock), Hydrus (the Lesser Water Snake), and Tucana (the Toucan) were created at the same time.
Centaurus hosts Omega Centauri (NGC 5139), the Milky Way’s brightest and largest globular cluster, and the open clusters NGC 3766 and NGC 5460. All three star clusters are visible to the unaided eye. The constellation also contains Centaurus A (NGC 5128), one of the nearest active galaxies to the Sun, and the bright planetary nebula NGC 3918, better known as the Blue Planetary or the Southerner.
Tucana appears in the southwestern sky. The constellation hosts 47 Tucanae, the second brightest globular cluster in the sky, after Omega Centauri. The cluster is easily visible to the unaided eye on a clear night