The stars in tonight’s sky form many familiar patterns that make their host constellations easy to identify.
For observers in the northern hemisphere, the brightest stars high overhead in the evening are Capella, Procyon and Pollux, the lucidae of the constellations Auriga (the Charioteer), Canis Minor (the Smaller Dog), and Gemini (the Twins).
For observers in the southern hemisphere, Sirius and Canopus, the brightest stars in Earth’s sky, are the nearest first magnitude stars to the zenith. Sirius, the Dog Star, is the brightest star in the constellation Canis Major (the Great Dog) and Canopus is the luminary of Carina (the Keel).
The stars visible tonight depend on the observer’s location and the time of night. The star maps below show the first and second magnitude stars visible in the night sky around 10 pm in the mid-northern, equatorial, and mid-southern latitudes.
Northern hemisphere
The stars of the Winter Hexagon still dominate the sky in the early evening. As the season progresses, they will keep shifting west earlier in the evening.
The Winter Hexagon (or Winter Circle) is formed by Sirius, Procyon, Pollux, Capella, Aldebaran, and Rigel. All these are first-magnitude stars, easily spotted even from urban areas.
Arcturus, the brightest star in the northern celestial hemisphere, rises in the east just before 10 pm. It is the brightest star in the spring constellation Boötes.
The stars of the Big Dipper dominate the northeastern sky, and the bright Regulus in Leo is prominent in the southeast. The stars of Cassiopeia, Andromeda and Perseus stand out in the northwestern sky.
Stars visible tonight in the northern hemisphere, image: Stellarium
Stars in the northern sky
The brightest stars in the northern sky shine at second magnitude. Polaris, the North Star, appears directly north. It is the nearest visible star to the north celestial pole and always appears in the same place from any given location.
Shining at magnitude 1.99, the supergiant is on average the 48th brightest star in the sky. It can be found by following a line drawn from Merak through Dubhe. Merak and Dubhe are the outer stars of the Big Dipper’s bowl. They appear high in the northeastern sky in the evening.
Polaris forms the Little Dipper with six fainter stars in the constellation Ursa Minor (the Smaller Bear). The asterism is difficult to spot in less-than-ideal conditions because the middle four stars are quite faint.
Kochab and Pherkad, the outer stars of the Little Dipper, are relatively bright and roughly parallel to Alioth and Mizar in the Big Dipper’s handle. They are known as the Guardians of the Pole because they appear close to the North Star and, like all other stars, they always appear to circle around it.
The stars of Draco take up much of the northern sky. The constellation has only one second-magnitude star, the orange giant Eltanin. Eltanin and its neighbour Rastaban mark the Dragon’s eyes and are part of an asterism that outlines the Dragon’s head. They appear close to the horizon in the evening. The fainter stars of the Dragon’s tail are found in the region between the Big and Little Dippers.
The five bright stars that form Cassiopeia’s W – Caph, Schedar, Gamma Cassiopeiae, Ruchbah, and Segin – are prominent in the northwestern sky. Cassiopeia’s brightest stars can be used to find the fainter stars of the neighbouring constellation Cepheus. A line extended from Schedar through Caph leads to Alderamin, the brightest star in Cepheus.
Stars in the northern sky tonight, image: Stellarium
Stars in the eastern sky
The stars of the spring constellations Boötes, Virgo and Leo rise in the east in the evening. Arcturus, the brightest star in Boötes, appears at the base of the Kite, an asterism that dominates the Herdsman constellation. The famous contrasting double star Izar is part of the asterism.
Shining at magnitude -0.05, Arcturus is the brightest star in the northern celestial hemisphere and the fourth brightest star in the sky. The orange giant lies 36.7 light-years away. It can be found by following the curved line formed by Alioth, Mizar and Alkaid, the stars of the Big Dipper’s handle.
The seven bright stars that form the Big Dipper appear high above the northeastern horizon. The asterism appears upside down in the evening throughout the winter months.
Megrez and Phecda, the inner stars of the Big Dipper’s bowl, can be used to find the Sickle, a relatively bright asterism that represents the head and mane of the celestial Lion. The Sickle appears as a backward question mark and has Regulus, Leo’s brightest star, at its base. Shining at magnitude 1.40, Regulus is the 21st brightest star in the sky. It marks the Lion’s heart. Denebola, the star that marks the Lion’s tail, appears lower in the eastern sky.
Denebola and the fainter Vindemiatrix in the constellation Virgo can be used to find the Virgo Cluster of galaxies. The centre of the cluster appears roughly halfway between the two stars. Vindemiatrix shines at third magnitude and is part of the Y of Virgo, an asterism that fully rises later in the evening. Spica, Virgo’s brightest star, appears at the base of the crooked Y and rises after 10 pm. Vindemiatrix is the leftmost star in the asterism. It appears almost directly east in the evening.
Stars in the eastern sky tonight, image: Stellarium
Stars in the western sky
The bright stars of Taurus and Auriga appear high above the western horizon. As the winter season progresses, they will keep setting earlier in the west.
Aldebaran, the brightest star in Taurus, is a K-type red giant located 65.3 light-years away. With an average apparent magnitude of 0.86, it is the 14th brightest star in the sky. The evolved giant lies in the same line of sight as the V-shaped Hyades cluster, which represents the Bull’s head. Aldebaran and Ain, one of the brightest Hyades stars, mark the Bull’s eyes.
Aldebaran lies on the imaginary line extended from the three bright stars of Orion’s Belt, Alnitak, Alnilam and Mintaka. These stars form Orion’s hourglass figure with Betelgeuse, Bellatrix, Rigel, and Saiph. Orion’s seven brightest stars are all exceptionally massive and luminous. Bellatrix is the only one that may not end its life as a supernova.
The V of the Hyades cluster points in the direction of the fainter Menkar, the star that marks the jaw of Cetus (the Sea Monster). Menkar appears lower above the western horizon and is part of a faint circle of stars that form the Sea Monster’s head.
Stars in the western sky tonight, image: Stellarium
Elnath, the second brightest star in Taurus, is part of Auriga’s hexagon, a conspicuous asterism formed by the brightest stars of Auriga (the Charioteer). The hexagon pattern appears almost overhead around 10 pm. Capella and Menkalinan, Auriga’s brightest stars, are the sixth and 41st brightest stars in the sky. Elnath is, on average, the 27th brightest star.
The bright stars of Andromeda and Perseus form a chain that appears almost perpendicular to the northwestern horizon in the evening. Alpheratz appears closest to the horizon and, depending on the location and geography, it may have already set by 10 pm.
Mirach and Almach in Andromeda form an almost straight line with Mirfak, the brightest star in Perseus. Mirfak is an F-type supergiant star located approximately 510 light-years away. It is the central star in the Alpha Persei Cluster, an open cluster visible to the unaided eye.
The famous variable star Algol, the second brightest star in Perseus, forms a triangle with Mirfak and Almach. The eclipsing binary star marks the head of the Gorgon Medusa.
Hamal, the brightest star in the constellation Aries (the Ram), appears below Algol in the evening. The orange giant lies 65.8 light-years away and is, on average, the 50th brightest star in the sky. It is part of a flat triangle asterism that appears near the fainter elongated triangle formed by the brightest stars of Triangulum.
Stars in the southern sky
The stars of the Winter Triangle – Sirius, Procyon and Betelgeuse – dominate the southern and southwestern sky. They can be used to find the faint constellation Monoceros (the Unicorn), most of which lies within the bright asterism.
Sirius and Procyon are the brightest stars in the dog constellations Canis Major and Canis Minor. Sirius is the brightest star in Earth’s sky, and Procyon is the eighth brightest star. Both stars lie in the solar neighbourhood, which is why they appear so bright.
Betelgeuse, on the other hand, lies hundreds of light-years away. It is the 10th brightest star in the sky and normally the second brightest star in Orion, after Rigel. The red supergiant is tens or hundreds of thousands of times more intrinsically luminous than the Sun. It is expected to go out as a spectacular supernova within the next 100,000 years.
With the exception of Sirius, the bright stars of Canis Major are also supernova candidates. Wezen and Aludra are massive supergiants located 1,600 and 2,000 light-years away, and Adhara and Mirzam are evolved B-type stars located 430 and 490 light-years away.
Stars in the southern sky tonight, image: Stellarium
Adhara, Wezen and Aludra form a prominent triangle below Sirius. They can be used to find the stars of the constellation Puppis.
Naos, the luminary of Puppis, appears close to the horizon in the evening. The hot blue supergiant is one of the nearest massive O-type stars to the solar system. It has a mass 56.1 times that of the Sun and shines with 813,000 solar luminosities. It lies approximately 1,080 light-years away.
The faint stars of Hydra occupy much of the southeastern sky. Even though it is the largest of the 88 constellations, Hydra is relatively inconspicuous. Its brightest star, the K-type giant or bright giant Alphard, is the 47th brightest star in the sky. It is about as bright as Mirzam in Canis Major and Polaris in Ursa Minor. Other stars of Hydra shine at magnitude 2.99 or fainter.
Equatorial latitudes
Sirius and Procyon, the luminaries of Canis Major and Canis Minor, are the brightest stars near the zenith in the evening. They are the brightest and eighth brightest stars in the sky. Both stars lie in the Sun’s neghbourhood. Sirius lies 8.60 light-years away and the older and more evolved Procyon is 11.46 light-years away.
Canopus, the brightest star in Carina and the second brightest star in the sky, appears south of Sirius, and the seven brightest stars of Orion dominate the western sky around 10 pm. Capella in Auriga and Aldebaran in Taurus are the brightest stars in the northwestern sky.
Spica and Regulus, the brightest stars in the zodiac constellations Virgo and Leo, are prominent above the eastern horizon, and the brightest stars of Ursa Major stand out in the northeastern sky. They form the Big Dipper, one of the most distinctive star patterns in the night sky.
The stars of the Southern Cross – Acrux, Mimosa, Gacrux, Imai, and Ginan – are conspicuous above the southeastern horizon. A line drawn through the axis of the Southern Cross points in the direction of the south celestial pole.
Stars visible tonight in equatorial latitudes, image: Stellarium
Northern sky
Pollux and Castor, the luminaries of the constellation Gemini, appear high in the northern sky in the evening. These stars appear similar in brightness and are easy to identify because they appear close to each other in the sky.
In reality, they could not be more different. The brighter Pollux is an evolved K-type giant with 1.91 times the Sun’s mass, located 33.78 light-years away. Unlike Castor, it is a single star. Castor is a sextuple star system located about 50 light-years away. The brightest components in the system are A-type stars about half the age of Castor. Pollux and Castor mark the heads of the Twins in the sky.
Capella, the brightest star in Auriga (the Charioteer), is the most prominent star in the northwestern sky. It forms Auriga’s hexagon with the fainter Menkalinan, Mahasim, Hassaleh and Almaaz in Auriga and Elnath in the neighbouring Taurus.
Shining at magnitude 0.08, Capella is the sixth brightest star in the sky and the third brightest star in the northern celestial hemisphere, after Arcturus and Vega. It is part of a multiple star system whose two main components form a spectroscopic binary star. Both components are evolved giant stars with about 2.5 times the Sun’s mass. The Capella system lies 42.9 light-years away.
The brightest stars of Perseus appear below Auriga’s hexagon around 10 pm. The supergiant Mirfak and the eclipsing binary star Algol appear roughly parallel to the northwestern horizon. Mirfak is part of the Segment of Perseus, a curving line of relatively bright stars that makes the constellation Perseus easy to identify on a clear night.
Stars in the northern sky tonight in equatorial latitudes, image: Stellarium
The faint constellations Camelopardalis and Lynx appear directly north. Their brightest stars, the yellow supergiant or bright giant Beta Camelopardalis and orange giant Alpha Lyncis, shine at magnitudes 4.02 and 3.14, and are challenging targets in light-polluted skies.
The seven stars that form the Big Dipper in Ursa Major – Alkaid, Mizar, Alioth, Megrez, Phecda, Dubhe, and Merak – dominate the northeastern sky. Alkaid, the star at the tip of the Great Bear’s tail and the end of the Big Dipper’s handle, may not be visible around 10 pm, depending on the location.
Alkaid and Dubhe are the only Big Dipper stars that are not members of the Ursa Major moving group, a stellar family formed in the same molecular cloud at around the same time. The other five stars have a similar motion through space, which is why the middle section of the Big Dipper will stay more or less the same for millions of years to come. Alioth, the brightest star in Ursa Major, shines at magnitude 1.77 from a distance of 82.6 light-years. Megrez, the only third-magnitude star in the Big Dipper, has an apparent magnitude of 3.312 and would not stand out in the sky if it were not part of the prominent northern asterism.
Eastern sky
Spica is the brightest star above the eastern horizon in the evening. Shining at magnitude 0.97, Virgo’s brightest star is the 16th brightest star in the sky. It is part of one of the closest massive binary systems to the Sun. Spica has a mass 11.43 times that of the Sun and its companion is 7.21 times more massive than our star. Both components are fast-spinning, hot, blue B-type stars. They lie 250 light-years away.
Spica appears at the base of an asterism known as the Y of Virgo. The left side of the large, crooked Y points in the direction of the faint constellation Coma Berenices and right side towards Leo.
Regulus, the luminary of Leo, appears high in the eastern sky. It is an evolved B-type star with 3.8 times the Sun’s mass and 316.2 times its luminosity. Regulus appears as a single star to the unaided eye but is in fact part of a quadruple star system located 79.3 light-years away. It spins at 318 km/s, completing a rotation every 15.9 hours. In comparison, the Sun takes 25 days.
Regulus marks the Lion’s heart. The hot blue star appears at the base of the Sickle of Leo, a relatively bright asterism that outlines the Lion’s head and mane. The fainter Denebola marks the Lion’s tail and appears closer to the horizon in the evening.
Stars in the eastern sky tonight in equatorial latitudes, image: Stellarium
Western sky
The bright stars of Orion and Taurus appear high in the western sky in the evening. Orion is almost overhead and Taurus appears a bit lower in the sky. Aldebaran, the brightest star in the Bull constellation, lies along the imaginary line extended from the three bright stars of Orion’s Belt.
The Belt stars Alnitak, Alnilam, and Mintaka are exceptionally massive and luminous O and B-type stars that shine at second magnitude from over 1,000 light-years away. Alnilam, the middle star of the Belt, is the brightest, most massive and most distant of the three. It lies approximately 2,000 light-years away and has a mass 64.5 times that of the Sun. It shines with 832,000 solar luminosities and is one of the most intrinsically luminous stars visible to the unaided eye.
Even though it appears close to Alnitak and Mintaka, these stars are in fact closer to each other than to Alnilam because they lie at a similar distance. Alnitak is 1,260 light-years away and Mintaka, 1,200 light-years away. They are both components in massive young star systems that contain multiple supernova candidates.
Rigel, Betelgeuse and Saiph are also supernova candidates. Rigel and Saiph are hot blue supergiants, and Betelgeuse is a cool red one. All three stars lie hundreds of light-years. Rigel and Betelgeuse are the seventh and 10th brightest stars in the sky.
Stars in the western sky tonight in equatorial latitudes, image: Stellarium
Rigel and Saiph can be used to find the fainter constellation Lepus (the Hare), which lies at Orion’s feet. The constellation is easy to identify because it looks like the animal it represents.
The large, faint constellations Eridanus and Cetus occupy much of the western sky closer to the horizon. Eridanus, the celestial river, stretches from Rigel in Orion all the way to the far southern sky, where the bright Achernar marks its end.
The red giant Menkar, the second brightest star in Cetus, is part of a circle of stars that form the head of Cetus (the Sea Monster). It can be found using the V-shaped Hyades cluster as a pointer. The cluster represents the Bull’s head. Aldebaran appears in the same line of sight as the Hyades but is not a member. The giant star marks one of the Bull’s eyes.
Southern sky
The brightest star in the southern sky is Canopus, the lucida of the constellation Carina and the second brightest star in the sky. The white bright giant star shines at magnitude -0.74 from a distance of 310 light-years. With a mass 8 times that of the Sun, the star’s ultimate fate is uncertain. It may end its life as a brilliant supernova or as a neon-oxygen white dwarf. Canopus has a radius 71 times that of the Sun and shines with 10,700 solar luminosities.
Canopus is one of three navigational stars in Carina, along with the second magnitude giants Miaplacidus and Avior. Miaplacidus, Carina’s second brightest star, forms an asterism known as the Diamond Cross with the fainter Theta, Upsilon and Omega Carinae.
The Diamond Cross is the faintest of the three prominent diamond-shaped asterisms in the far southern sky. The other two – the False Cross and the Southern Cross – are also visible in the evening sky.
The False Cross is formed by Avior and Aspidiske in Carina with Alsephina and Markeb in Vela. It is often mistaken for the Southern Cross, an asterism commonly used to find true south.
Stars in the southern sky tonight in equatorial latitudes, image: Stellarium
The Southern Cross appears low above the southeastern horizon around 10 pm. It is composed of the first magnitude Acrux and Mimosa, the second magnitude Gacrux, and the fainter Imai and Ginan. These are the five brightest stars of Crux, the smallest constellation in the sky. Despite its size, Crux is the most identifiable constellation in the southern hemisphere. Its main star pattern – the Southern Cross – appears on many state flags, including Brazil, Australia, and New Zealand.
The bright stars of Carina, Puppis and Vela – the constellations that once formed Argo Navis – form a straight line that appears almost perpendicular to the southern horizon in the evening. Regor in Vela and Naos in Puppis appear directly above Avior in the evening.
Naos, the brightest star in Puppis, is one of the most luminous stars visible to the unaided eye. The hot blue O-type supergiant has a mass 56.1 times that of the Sun and shines with 813,000 solar luminosities from a distance of 1,080 light-years.
Regor (Gamma2 Velorum) is part of a multiple star system that includes a Wolf-Rayet star and a massive hot blue supergiant. The star system lies approximately 1,096 light-years away. The brighter components are supernova candidates.
Southern hemisphere
Sirius and Canopus, the brightest stars in the sky, appear high overhead around 10 pm. Rigil Kentaurus and Hadar, the third and 10th brightest stars, appear low in the southeastern sky. They point towards the top of the Southern Cross, one of the brightest and most recognizable asterisms in the far southern sky.
Achernar, the ninth brightest star, appears high in the southwest, and Aldebaran and the bright stars of the constellation Orion are prominent in the northwestern sky. Procyon, Pollux and Regulus are the brightest stars in the northeast. They are the luminaries of the constellations Canis Minor (the Smaller Dog), Gemini (the Twins), and Leo (the Lion).
Stars visible tonight in the southern hemisphere, image: Stellarium
Northern sky
Several first-magnitude stars are visible in the northern sky around 10 pm. Betelgeuse and Rigel, the brightest stars of the constellation Orion appear high in the sky. The supergiants form the constellation figure of the celestial Hunter with Bellatrix, Saiph, and Orion’s Belt stars Mintaka, Alnilam and Alnitak.
A line extended from Orion’s Belt to the northwest leads to Aldebaran, the brightest star in Taurus. The evolved giant star forms the Bull’s head with the brightest stars in the V-shaped Hyades cluster. Aldebaran marks one of the Bull’s eyes.
Elnath, the second brightest star in Taurus, marks the Bull’s northern horn. It is part of Auriga’s hexagon, a prominent asterism that may not be fully visible from the southern hemisphere in the evening. Capella and Menkalinan, the brightest stars of Auriga may be below the horizon, depending on the location and geography.
Pollux and Castor, the brightest stars in Gemini, appear east of Auriga and Taurus. They mark the heads of the mythical Twins.
Procyon, the brightest star in Canis Minor and the eighth brightest star in the sky, appears above Pollux around 10 pm. The evolved F-type star lies only 11.46 light-years away and is one of our nearest neighbours.
Stars in the northern sky tonight in the southern hemisphere, image: Stellarium
Eastern sky
The faint constellations Hydra, Corvus, Crater, Antlia, and Sextans, occupy much of the eastern sky. Only Hydra, the largest constellation in the sky, contains one second-magnitude star. The evolved K-type star Alphard shines at magnitude 2.00 from a distance of 177 light-years. It is the only relatively bright star southwest of the Sickle of Leo.
The faint stars of Sextans lie in the region between Alphard and the constellation Leo, and the stars of Crater may be made out directly east, below Hydra, on a clear, dark night.
The brighter stars of the neighbouring Corvus form an asterism known as the Sail or Spica’s Spanker. One side of the asterism points towards the bright Spica, the luminary of Virgo. Spica rises later in the evening.
Regulus, the brightest star in Leo, stands out in the northeastern sky. The hot blue subgiant star marks the base of the Sickle, a star pattern that represents the Lion’s head and mane. The bright Denebola at the Lion’s tail rises after 10 pm.
Stars in the eastern sky tonight in the southern hemisphere, image: Stellarium
Western sky
The stars of the relatively faint constellations Cetus and Eridanus take up most of the western sky. Cetus has a single second-magnitude star, the orange giant Diphda. Diphda has an apparent magnitude of 2.02 and lies 96.3 light-years away. It appears in the Sea Monster’s tail. Menkar, the constellation’s second brightest star, appears in the head of Cetus, which can be found using the V-shaped Hyades cluster on a clear night.
Achernar, the brightest star in Eridanus, appears high in the southwestern sky in the evening. It marks the end of the celestial River. Cursa, the constellation’s second brightest star, lies at the River’s other end, near Rigel. Cursa is a third-magnitude white giant located about 90 light-years away.
Achernar shines at magnitude 0.40 – 0.46 from an approximate distance of 139 light-years. It is the ninth brightest star in the sky. The hot blue star has a mass 6 times that of the Sun and is 3,493 times more luminous than our star. It is one of the fastest spinners visible to the unaided eye, with a projected rotational velocity of 250 km/s. Due to its high spin rate, the star has an oblate shape. It is flattened at the poles and has an equatorial bulge. It is one of the least spherical stars known in the Milky Way.
Ankaa, the luminary of Phoenix, lies just below Achernar. It is an orange giant star located 82 light-years away. The star’s name comes from the Arabic word for “phoenix.”
Hamal, the brightest star in the constellation Aries, may be visible very low above the northwestern horizon depending on the location.
Stars in the western sky tonight in the southern hemisphere, image: Stellarium
Southern sky
Atria, the brightest star of Triangulum Australe, appears above the southern horizon in the evening. It is part of a relatively bright triangle that gives the constellation its name. The orange giant or bright giant has an apparent magnitude of 1.91. It has 7 times the Sun’s mass and is 5,500 times more luminous.
The triangle of Triangulum Australe points towards the Southern Birds constellations Pavo (the Peacock) and Grus (the Crane). Peacock and Alnair, the brightest stars in these constellations, are among the bright stars selected for use in celestial navigation. Both are hot blue B-type stars much more massive and luminous than the Sun.
Four exceptionally bright stars appear in the southeastern sky in the evening. Rigil Kentaurus and Hadar (Alpha and Beta Centauri) are the third and 11th brightest stars in the sky, and Acrux and Mimosa (Alpha and Beta Crucis) are the 13th and 20th brightest stars.
Alpha and Beta Centauri are known as the Southern Pointers because they point towards the true Southern Cross, an asterism that can be used to find true south. Alpha Centauri is the nearest star system to the Sun. It lies only 4.344 light-years away and contains Proxima Centauri, the nearest star to the solar system, located 4.2465 light-years away.
The brighter components of Alpha Centauri – Rigil Kentaurus and Toliman – are Sun-like main sequence stars with masses and radii similar to that of the Sun. Rigil Kentaurus is a yellow dwarf and Toliman is an orange dwarf. Proxima Centauri is the only component that is not visible to the unaided eye. The red dwarf has only 12.21% of the Sun’s mass and shines with 0.1567% of its luminosity.
Like Rigil Kentaurus, Hadar is the primary component in a triple star system. However, the components of Beta Centauri are much more massive, luminous, and distant. Hadar itself is a supernova candidate. It is a hot blue giant with 12.02 times the Sun’s mass and 31,600 times its luminosity. It lies approximately 390 light-years away.
Stars in the southern sky tonight in the southern hemisphere, image: Stellarium
The brightest stars of Crux – Acrux, Mimosa, Gacrux, Imai, and Ginan – form the Southern Cross, the most identifiable asterism in the southern hemisphere. Acrux, Mimosa and Imai are believed to be members of the same family, the Lower Centaurus-Crux subgroup of the Scorpius-Centaurus association (Sco OB2). They are hot, blue, evolved B-type stars located 320, 280 and 345 light-years away, respectively. With masses of 17.80, 16 and 8.9 solar masses, the stars are supernova candidates. They are only 10 to 20 million years old.
Gacrux and the fainter Ginan are older and cooler stars. Gacrux is a red giant located 88.6 light-years away and Ginan is a K-type giant approximately 230 light-years away. With masses 1.5 times that of the Sun, the stars will end their lives surrounded by planetary nebulae. The same fate awaits our Sun in about 4-5 billion years.