The stars in tonight’s sky form many familiar patterns that make their host constellations easy to identify.
In the northern hemisphere, the stars of the Summer Triangle – Vega, Altair, and Deneb – appear high overhead in the evening. Capella and Fomalhaut are the only other first-magnitude stars above the horizon around 10 pm. Arcturus may also be visible in the west early in the month, depending on the location.
In the southern hemisphere, Fomalhaut is the brightest star near the zenith in the evening. Altair and Achernar also appear high in the sky around 10 pm, while Canopus, Antares, and the bright stars of the constellations Crux and Centaurus are closer to the horizon.
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 southern latitudes.
Northern hemisphere
The bright Vega in the constellation Lyra (the Harp), Altair in Aquila (the Eagle), and Deneb in Cygnus (the Swan) appear high overhead in the evening in the late summer. The three stars form the Summer Triangle, an asterism that dominates the night sky throughout the summer months.
Vega and Altair are the fifth and 12th brightest stars in the sky. Even though both stars are hotter and more luminous than the Sun, they appear so bright mainly because they are close by. Vega lies 25.04 light-years away and Altair only 16.73 light-years away.
Deneb, on the other hand, lies 2,615 light-years away. The white supergiant is the 19th brightest star in the sky because it is exceptionally luminous. It has an energy output of 196,000 Suns and is one of the brightest supernova candidates in the sky. The star marks the top of the Northern Cross and the tail of the celestial Swan.
Altair forms the Shaft of Aquila with Tarazed and Alshain, the two relatively bright stars that flank it. The asterism can be used to find the fainter stars of the constellations Sagitta (the Arrow) and Delphinus (the Dolphin).
Stars visible tonight in the northern hemisphere, image: Stellarium
Northern sky
The bright stars of Ursa Major (the Great Bear) are prominent in the northern and northwestern sky. Seven of them form the Big Dipper, one of the most recognizable asterisms in the northern night sky. Six of these stars, including the constellation’s luminary Alioth, shine at second magnitude and are easily visible even in urban skies. The fainter Megrez, one of the inner stars of the Dipper’s bowl, is a third magnitude star.
Merak and Dubhe, the outer stars of the bowl, are known as the Pointer Stars because they point toward Polaris, the North Star. Polaris is not exceptionally bright, but it stands out in a relatively faint area of the northern sky. It is the brightest star in the constellation Ursa Minor (the Little Bear) and marks the end of the Little Dipper’s handle. The only other second-magnitude star in the constellation is Kochab, one of the outer stars of the Little Dipper’s bowl.
Kochab and the fainter Pherkad are known as the Guardians of the Pole because they always circle close to Polaris and the north celestial pole.
Stars in the northern sky tonight, image: Stellarium
The constellation figure of Cepheus (the King) appears near Polaris. The stick house figure can be found using the brighter stars of Cassiopeia’s W. A line drawn from Schedar to Caph and extended by about three times the distance as that between the two stars, leads to Alderamin, the brightest star in Cepheus.
The fainter stars of Draco’s tail appear in the region between the two Dippers. Eltanin, the brightest star in Draco, marks one of the Dragon’s eyes (Rastaban marks the other) and is part of a quadrilateral asterism that outlines the Dragon’s head.
Capella, the brightest star in the constellation Auriga (the Charioteer) and the sixth brightest star in the sky, appears low above the northeastern horizon. It forms Auriga’s hexagon, a familiar northern asterism, with Menkalinan, Hassaleh, Mahasim and Almaaz in Auriga and Elnath in the neighbouring Taurus (the Bull). The asterism is only partly visible around 10 pm.
Eastern sky
The stars of Andromeda and Pegasus appear high above the eastern horizon in the evening. The supergiant Enif, the brightest star in Pegasus, appears high in the southeastern sky. It forms an asterism known as the Lightning Bolt with the fainter luminaries of Aquarius (Sadalsuud and Sadalmelik) and Capricornus (Deneb Algedi).
The constellation Pegasus is dominated by a bright, large asterism called the Great Square of Pegasus. The asterism represents the main body of the mythical Winged Horse. It is formed by the Pegasus stars Scheat, Markab and Algenib with Alpheratz in the constellation Andromeda.
The Great Square can be used to find two fainter nearby asterisms, the Circlet of Pisces and the Water Jar of Aquarius, both of which appear near Markab.
A line extended from Scheat through Markab across the sky leads to Fomalhaut, the brightest star in the constellation Piscis Austrinus (the Southern Fish) and the 18th brightest star in the sky. Fomalhaut marks the mouth of the Southern Fish.
Stars in the eastern sky tonight, image: Stellarium
Diphda, the lucida of Cetus (the Sea Monster) appears low in the southeastern sky. The giant star marks the Sea Monster’s tail.
Alpheratz in the Great Square is one of the three bright stars in Andromeda that form a chain between Pegasus and Perseus. Mirach, the middle star in the chain, can be used to find the Andromeda Galaxy (M31) and the Triangulum Galaxy (M33), the most distant objects visible without binoculars. Almach, the leftmost star in the chain, can be used as a guide to the bright open cluster Messier 34 and the spiral galaxy NGC 891 (the Silver Sliver Galaxy).
The supergiant Mirfak, the brightest star in Perseus, extends the chain towards north. Mirfak is the brightest star in the Alpha Persei Cluster, an open cluster visible to the unaided eye on a clear night. Mirfak is also the brightest point of light in the Segment of Perseus, an asterism formed by a curved line of stars that stretches between the W of Cassiopeia and Auriga’s hexagon. The famous eclipsing variable star Algol, the second brightest star in Perseus, forms a triangle with Mirfak and Almach.
Hamal, the luminary of Aries (the Ram), appears directly below Mirach in the evening. The orange giant forms a flat triangle with the fainter Sheratan and Mesarthim. The three Aries stars appear below the elongated triangle formed by the brightest stars of the constellation Triangulum.
The five brightest stars of Cassiopeia appear high above the northeastern horizon. They form a distinctive W in the sky that can be used to find several notable deep sky objects that appear in this area. These include the Double Cluster (NGC 869 and NGC 884), the Heart and Soul nebulae (Sharpless 2-190 and Sharpless 2-199), and the open clusters Messier 52 and Messier 103.
Western sky
The stars of Ophiuchus (the Serpent Bearer), Serpens (the Serpent), Corona Borealis (the Northern Crown), and Boötes (the Herdsman) set in the west in the evening. Arcturus, the brightest star in the northern celestial hemisphere, appears at the base of the Kite in Boötes and may or may not be visible around 10 pm, depending on the location and geography. The slightly fainter Izar, one of the finest double stars in the sky, is part of the Kite asterism. The binary star system can be resolved in a small telescope.
Alphecca, the brightest star in the Northern Crown, is the middle star in a semi-circle that represents the crown of Ariadne in Greek mythology. Traditionally also called Gemma, the star marks the jewel in the crown. It is part of an eclipsing binary system located approximately 75 light-years from the Sun.
The stars of Hercules appear in the region between the Kite and the bright Vega. Four relatively bright Hercules stars form the Keystone, an asterism that outlines the torso of the mythical hero.
Stars in the western sky tonight, image: Stellarium
The polygon of Ophiuchus takes up a sizeable portion of the southwestern sky. The fast-spinning Rasalhague, the brightest star in Ophiuchus, appears at the top of the polygon. It marks the Serpent Bearer’s head. The evolved A-type star spins at about 88.5% of its breakup velocity. As a result, it has an oblate shape.
Sabik, the constellation’s second brightest star, forms the base of the polygon with Zeta Ophiuchi, Yed Prior, and Yed Posterior. Unukalhai, the brightest star in Serpens, appears along the same line.
Southern sky
The stars of the faint zodiac constellation Capricornus appear directly south around 10 pm. Deneb Algedi, the brightest star in Capricornus, is a third magnitude star. It is the leftmost point of light in the V-shaped constellation figure of the celestial Sea Goat.
The bright Fomalhaut stands out in the southeastern sky. It is the only first-magnitude star in a region without any other first- or second-magnitude stars. The young star marks the mouth of the Southern Fish (Piscis Austrinus), into which the neighbouring Aquarius is pouring water.
Aquarius, the Water Bearer, does not contain any first- or second-magnitude stars. Its brightest stars, the yellow supergiants Sadalsuud and Sadalmelik, shine at magnitudes 2.87 and 2.94. They are believed to be associated with the orange supergiant Enif, the brightest star in Pegasus.
Enif, Sadalsuud, Sadalmelik and Deneb Algedi form an asterism known as the Lightning Bolt.
Stars in the southern sky tonight, image: Stellarium
The stars of Sagittarius (the Archer) dominate the southwestern sky. The constellation’s brightest stars from the Teapot, a recognizable asterism that lies next to the Milky Way’s bright band.
Kaus Australis, the brightest star in Sagittarius, forms the Archer’s bow with the fainter Kaus Media and Kaus Borealis. Kaus Australis is a hot blue giant, and the other two stars are cool orange giants.
Nunki, the second brightest star in Sagittarius, is part of the Teapot’s handle. It is a hot blue main sequence star with 7.8 times the Sun’s mass and a luminosity of 3,300 Suns.
Equatorial latitudes
The brightest stars visible in the evening are Vega in the constellation Lyra (the Lyre), Achernar in Eridanus (the River), Altair in Aquila (the Eagle), Antares in Scorpius (the Scorpion), Fomalhaut in Piscis Austrinus (the Southern Fish), and Deneb in Cygnus (the Swan).
Vega, Altair, Deneb, and Antares are easily recognizable because they form prominent asterisms. Vega, Altair and Deneb form the Summer Triangle, while Antares is part of the Fish Hook of Scorpius. Achernar and Fomalhaut appear relatively isolated in the sky, with few other bright stars in the vicinity.
Stars visible tonight in equatorial latitudes, image: Stellarium
Northern sky
The brightest star in the northern sky is Deneb, the luminary of the constellation Cygnus (the Swan). The supergiant sits atop the Northern Cross, a conspicuous asterism that outlines the body of the celestial Swan. A line extended through the beam of the Cross points to Eltanin, the brightest star in Draco (the Dragon). Eltanin is an orange giant that marks one of the Dragon’s eyes and is part of a star pattern that represents the Dragon’s head.
Deneb forms the Summer Triangle with the brighter Vega and Altair, which appear in the northwestern sky. Vega and Altair, the brightest stars in the constellations Lyra (the Lyre) and Aquila (the Eagle), are much closer to the Sun than Deneb. Both are A-type stars, hotter and more luminous than the Sun, but they appear so bright primarily because they lie in the Sun’s neighbourhood.
In contrast, Deneb lies 2,615 light years away and is by far the most distant first magnitude star. With a mass 19 times that of the Sun, the supergiant is one of the brightest supernova candidates in the sky. Its Northern Cross neighbour Sadr, another supergiant, is also destined to go out as a supernova. It has a mass of 12.11 solar masses and lies approximately 1,800 light years away.
Stars in the northern sky tonight in equatorial latitudes, image: Stellarium
Alderamin, the brightest star in the constellation Cepheus (the King), appears almost directly north. It can be identified using the bright stars of Cassiopeia, which form a distinctive W in the sky. A line drawn from Schedar through Caph leads to Alderamin.
Gamma Cassiopeiae, the middle star of Cassiopeia’s W, is another supernova candidate. The hot blue subgiant star is already approaching the end of its life even though it is only around 8 million years old. It is an exceptionally fast spinner, with a projected rotational velocity of 432 km/s. As a result, it is flattened at the poles and has an equatorial bulge.
Eastern sky
The eastern sky is relatively devoid of exceptionally bright stars. Hamal and Diphda, the brightest stars of Aries (the Ram) and Cetus (the Sea Monster), shine at second magnitude in relatively inconspicuous constellations.
The stars of Pegasus, Andromeda and Perseus dominate the northeastern sky. The Great Square of Pegasus appears high in the northeast. It is formed by three bright Pegasus stars – Scheat, Markab and Algenib – with Alpheratz in the neighbouring Andromeda.
Alpheratz, Mirach and Almach, Andromeda’s brightest stars, form a straight line that points towards Mirfak, the brightest star in Perseus. The supergiant is the most prominent member of the Alpha Persei Cluster, an open cluster visible to the unaided eye. The cluster stretches over more than 6 degrees and shines at magnitude 1.2. The famous eclipsing variable star Algol appears in the same area. It marks the head of the Gorgon Medusa in Perseus.
The bright Ankaa appears high in the southeastern sky. Its name comes from the Arabic word for “phoenix,” which is the name of its host constellation. The orange giant is the brightest star between the brighter Fomalhaut in the constellation Piscis Austrinus (the Southern Fish) and Achernar in Eridanus (the River).
Stars in the eastern sky tonight in equatorial latitudes, image: Stellarium
Western sky
The bright Altair appears high in the western sky. Shining at magnitude 0.76 from a distance of only 16.73 light-years, it is the 12th brightest star in the sky. It marks the head or neck of the Eagle and is flanked by two fainter stars, Tarazed and Alshain. Together with these stars, Altair forms an asterism known as the Shaft of Aquila (or Family of Aquila).
Rasalhague, the brightest star of Ophiuchus (the Serpent Bearer), appears almost directly below Altair, roughly halfway between Vega and Antares. The fast-spinning white giant forms a binary system with a class K main sequence star. It marks the top of a polygon formed the brightest stars of Ophiuchus. Sabik, the only other second magnitude star in the constellation, forms the base of the polygon with Zeta Ophiuchi, Yed Prior, and Yed Posterior. The stars appear near the Scorpion’s claws.
Stars in the western sky tonight in equatorial latitudes, image: Stellarium
The red supergiant Antares appears low above the horizon in the evening. The massive star is part of the Fish Hook, an asterism that dominates the constellation Scorpius. The Scorpion’s stinger is marked by the bright Shaula, which appears in the southwestern sky, and its fainter neighbour Lesath.
The stars of Sagittarius form the Teapot asterism, which appears just above the Fish Hook in the evening. Kaus Australis, the constellation’s brightest star, is a hot blue B-type giant located approximately 143 light-years away. It forms the celestial Archer’s bow with th orange giants Kaus Media and Kaus Borealis. Nunki, the second brightest star in Sagittarius, is part of the Teapot’s handle.
Southern sky
The brightest stars in the southern sky in the evening are Peacock and Alnair, the luminaries of Pavo (the Peacock) and Grus (the Crane). The constellations Pavo, Grus, Tucana (the Toucan) and Phoenix are collectively known as the Southern Birds. The orange giant Alpha Tucanae, the brightest star in Tucana, is a third magnitude star. It appears below Alnair in Grus around 10 pm. Ankaa, the lucida of Phoenix, appears between Achernar and Fomalhaut in the southeastern sky. Its name is derived from the Arabic word for “phoenix.”
Like Ankaa, Peacock takes its name from its host constellation. The hot blue main sequence star has 5.91 times the Sun’s mass and shines with 2,200 solar luminosities. It lies 179 light-years away and has an estimated age of 48 million years.
Stars in the southern sky tonight in equatorial latitudes, image: Stellarium
Alnair, the lucida of Grus, is also a B-type main sequence star. It lies 101 light-years away and is 520 times more luminous than the Sun and four times more massive. The slightly fainter Tiaki is a red giant with 2.4 times the Sun’s mass and a luminosity of 2,500 Suns.
Fomalhaut and Achernar, the brightest stars in Piscis Austrinus (the Southern Fish) and Eridanus (the River) are the 18th and 9th brightest stars in the sky. Fomalhaut marks the mouth of the Southern Fish, while Achernar marks the end of the celestial River.
Fomalhaut is part of a triple star system and Achernar forms a binary star with a fainter companion. Fomalhaut is much closer to us at a distance of 25.13 light-years, while Achernar lies approximately 139 light-years away.
Southern hemisphere
The evening sky in the southern hemisphere hosts several first-magnitude stars. The bright Vega, Deneb and Altair form a large triangle that dominates the northern and northwestern sky.
Achernar is prominent high in the southeast and Fomalhaut appears overhead around 10 pm. Antares and the Fish Hook of Scorpius appear above the western horizon, while the Southern Pointers, Rigil Kentaurus and Hadar, dominate the southwestern sky. They appear near the bright stars of the Southern Cross.
Canopus, the brightest star in Carina and the second brightest star in the sky, lies low above the southern-southeastern horizon in the evening.
Stars visible tonight in the southern hemisphere, image: Stellarium
Northern sky
The stars of the Summer Triangle and the Great Square of Pegasus are prominent in the northern sky. Altair, Deneb and Vega, the brightest stars in the constellations Aquila (the Eagle), Cygnus (the Swan) and Lyra (the Lyre), form the Summer Triangle, one of the brightest and largest asterisms in the sky. Deneb appears low above the northern horizon, Vega is more to the northeast, and Altair is high above the horizon around 10 pm.
The supergiant Deneb marks the tail of the Swan and the top of the Northern Cross, a conspicuous asterism that appears upside down in the southern hemisphere. Sadr, a fellow supergiant, appears in the centre of the Cross and marks the Swan’s chest, and the bright Aljanah marks one of the Swan’s wings. Fawaris at the other wing and Albireo at the Swan’s beak are fainter, but easily visible even from areas with some light pollution.
The Great Square of Pegasus is formed by Alpheratz in the constellation Andromeda with Scheat, Markab and Algenib in Pegasus. The asterism outlines the body of the mythical horse. Enif, the brightest star in Pegasus, is not part of the pattern. It marks the muzzle of Pegasus and appears southwest of the asterism.
Stars in the northern sky tonight in the southern hemisphere, image: Stellarium
Eastern sky
Diphda, the brightest star in the constellation Cetus (the Sea Monster), appears almost directly east, high above the horizon in the evening. The giant star marks the Sea Monster’s tail and was traditionally known as Deneb Kaitos.
Achernar, the ninth brightest star in the sky, marks the end of the celestial River (Eridanus). It appears high in the southeastern sky around 10 pm. It can be used to find the fainter Ankaa, the brightest star in the constellation Phoenix.
Stars in the eastern sky tonight in the southern hemisphere, image: Stellarium
Western sky
Antares is the brightest star in the western sky. The luminary of the Scorpius constellation is the 15th brightest star in the sky. The supergiant star is part of the Fish Hook, an asterism that outlines the body and tail of the celestial Scorpion. Shaula, the star that marks the Scorpion’s stinger, appears directly above Antares in the evening. The hot blue star lies near the border with the constellation Sagittarius.
The stars of the fainter constellation Lupus (the Wolf) appear in the region between the Scorpion’s claws and the Southern Pointers, Rigil Kentaurus and Hadar in the constellation Centaurus. The hot blue giant Alpha Lupi, the brightest star in Lupus, is one of the nearest supernova candidates to the Sun. It lies at an approximate distance of 460 light-years.
Stars in the western sky tonight in the southern hemisphere, image: Stellarium
The brightest stars in Sagittarius form the Teapot, an asterism that appears next to the Milky Way’s band. The Archer constellation contains two second magnitude stars, Kaus Australis and Nunki. Even though other stars of the Teapot are fainter, the asterism is easily visible from areas without too much light pollution.
The stars of Ophiuchus, the 11th largest constellation in the sky, are easy to identify because they form a large polygon that appears perpendicular to the horizon around 10 pm. Rasalhague, the constellation’s brightest star, marks the top of the polygon, and Sabik, the second brightest star, forms the base with the fainter Zeta Ophiuchi, Yed Prior, and Yed Posterior.
Southern sky
Several first-magnitude stars appear in the southeastern and southwestern sky in the evening. Canopus, the second brightest star in the sky, appears low above the southern-southeastern horizon. The bright giant star is the lucida of the constellation Carina (the Keel). It lies 310 light-years away and has an apparent magnitude of -0.74.
Alpha Centauri, the brightest star in Centaurus and third brightest star in the sky, appears above the southwestern horizon. It is in fact a triple star system composed of Rigil Kentaurus, Toliman, and Proxima Centauri, the nearest individual star to Earth. While Proxima is invisible to the unaided eye, the two brighter components appear as a single star that can usually be resolved in binoculars and small telescopes.
Alpha and Beta Centauri (Rigil Kentaurus and Hadar) are called the Southern Pointers. The stars point towards the Southern Cross, an asterism that can be used to find the south celestial pole.
Stars in the southern sky tonight in the southern hemisphere, image: Stellarium
Even though they appear close in the sky, the two points of light are not physically close. Alpha Centauri is the nearest star system to the Sun, located only 4.344 light-years away, while Beta Centauri lies approximately 390 light-years away. Beta Centauri is also a triple star system. However, while the components of Alpha Centauri are still on the main sequence, the brighter components of Beta Centauri are hot, luminous B-type giant stars that are much more intrinsically luminous.
The bright Atria in the constellation Triangulum Australe (the Southern Triangle) appears in the same area as Alpha and Beta Centauri. The orange giant or bright giant is part of a conspicuous triangle that gives the constellation its name.
The Southern Cross, the best-known asterism in the southern hemisphere, is formed by the first-magnitude Acrux and Mimosa, the second-magnitude Gacrux, and the fainter Imai and Ginan. Acrux, Mimosa and Gacrux are the 13th, 20th and 25th brightest stars in the sky, respectively. Acrux and Mimosa are evolved luminous blue B-type stars and Gacrux is a red giant. A line extended from Gacrux through Acrux passes near the location of Polaris Australis, the nearest visible star to the south celestial pole.