Cool Star Facts

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• Sirius is the brightest star in the night sky and one of the closest: its light takes about 8.6 years to reach us. It belongs to Canis Major, the Great Dog, and NASA's headlines still call it the Dog Star.

  Sirius: the guide · NASA Science, Astronomers Use Hubble to 'Weigh' Dog Star's Companion (2005) (opens in a new tab)

• Polaris is the North Star: the star nearest the point that the northern sky turns around. Because it barely moves, it shows the direction of north at night to anyone in the Northern Hemisphere. It is not, despite its fame, a particularly bright star.

  Polaris: the guide · Preston Dyches, What is the North Star and How Do You Find It?, NASA Science (2021, updated 2024) (opens in a new tab)

• Vega is the brightest star in the small constellation Lyra, the Lyre, and the brightest corner of the Summer Triangle. It is 25 light-years away: the light you see left it about 25 years ago.

  Vega: the guide · NASA JPL, Tiny Particles, So Far Away (PIA07218, 2005) (opens in a new tab)

• Betelgeuse is the reddish star at Orion's shoulder: a red supergiant so large that, put in place of the Sun, its surface would reach beyond the orbit of Jupiter. In 2019 and 2020 it faded so much that people noticed with the naked eye.

  Betelgeuse: the guide · NASA Science, Discovering the Universe Through the Constellation Orion (opens in a new tab)

• Rigel marks Orion's foot. It is a blue-white supergiant and usually the brightest star in Orion, even though it carries the second Greek letter, beta.

  Rigel: the guide · Jim Kaler, Rigel, STARS (University of Illinois) (opens in a new tab)

• Arcturus is the brightest star north of the celestial equator, a warm orange star in Boötes, the herdsman. It is easy to find, it is moving faster across the sky than almost any other bright star, and it once turned on the lights of a World's Fair.

  Arcturus: the guide · ESA, Hipparcos: The 50 Brightest Stars (opens in a new tab)

• Capella is the brightest star in Auriga, the Charioteer, and the first-magnitude star nearest the north celestial pole. What looks like one yellowish star is two giant stars circling each other every 104 days.

  Capella: the guide · Jim Kaler, Capella, STARS (University of Illinois) (opens in a new tab)

• Antares is the reddish star at the heart of Scorpius, a red supergiant about 700 times the Sun's diameter. Its name compares it to Mars, and it is easy to see why.

  Antares: the guide · ESO, Best Ever Image of a Star's Surface and Atmosphere (eso1726, 2017) (opens in a new tab)

• Canopus is the second-brightest star in the night sky, in the southern constellation Carina. From much of the Northern Hemisphere it never rises at all, which is why many people have never heard of it.

  Canopus: the guide · ESA, Hipparcos: The 50 Brightest Stars (opens in a new tab)

• Alpha Centauri is the nearest star system to the Sun: three stars a little over four light-years away. To the naked eye the two bright ones merge into a single point, the third-brightest in the night sky.

  Alpha Centauri: the guide · NASA Science, Our Nearest Celestial Neighbor? An Exotic 3-Star System (opens in a new tab)

• Orion is one of the few star patterns almost anyone can pick out: a bright hourglass with three stars in a row across its middle. Red Betelgeuse marks his shoulder, blue-white Rigel his foot.

  Orion: the guide · NASA Science, Discovering the Universe Through the Constellation Orion (opens in a new tab)

• Ursa Major, the Great Bear, is the third-largest constellation. Its seven brightest stars, the Big Dipper or Plough, form only the bear's back and tail; the rest of the animal is made of fainter stars.

  Ursa Major: the guide · Ian Ridpath, Star Tales: Ursa Major (opens in a new tab)

• Ursa Minor, the Little Bear, holds Polaris at the tip of its tail. Its seven main stars make a smaller, fainter ladle, the Little Dipper, that turns around the pole all night.

  Ursa Minor: the guide · Ian Ridpath, Star Tales: Ursa Minor (opens in a new tab)

• Cassiopeia's five brightest stars make a W, or an M, depending on the time of night. From mid-northern latitudes the queen circles the pole and never sets.

  Cassiopeia: the guide · Ian Ridpath, Star Tales: Cassiopeia (opens in a new tab)

• Andromeda is a chain of three bright stars running out from the Great Square of Pegasus. In its direction, far beyond its stars, lies the Andromeda Galaxy, M31, the most distant thing most people will ever see with their own eyes.

  Andromeda: the guide · Ian Ridpath, Star Tales: Andromeda (opens in a new tab)

• Cygnus, the swan, flies down the Milky Way with its wings outstretched. Its brightest stars make a large cross, the Northern Cross, with Deneb at the top.

  Cygnus: the guide · Ian Ridpath, Star Tales: Cygnus (opens in a new tab)

• Lyra is small but easy to find, because it holds Vega, the fifth-brightest star. Beside Vega a little figure of fainter stars makes the frame of the lyre.

  Lyra: the guide · Ian Ridpath, Star Tales: Lyra (opens in a new tab)

• Aquila, the eagle, is marked by Altair, a bright star with a fainter star close on each side. Altair spins so fast that it bulges at its equator.

  Aquila: the guide · Ian Ridpath, Star Tales: Aquila (opens in a new tab)

• Scorpius really looks like its namesake: a curving line of stars ending in a raised sting, with red Antares at the heart. It lies on the Sun's yearly path, low in the south for northern observers and high overhead for southern ones.

  Scorpius: the guide · Ian Ridpath, Star Tales: Scorpius (opens in a new tab)

• Sagittarius is a centaur drawing a bow at the scorpion next door. Its brightest stars make the Teapot, and just beyond them lies the direction of the centre of our Galaxy.

  Sagittarius: the guide · Ian Ridpath, Star Tales: Sagittarius (opens in a new tab)

• Leo is one of the few constellations that looks like what it is named for: a crouching lion. Six stars in the shape of a sickle outline his head and chest, with bright Regulus at the bottom.

  Leo: the guide · Ian Ridpath, Star Tales: Leo (opens in a new tab)

• Taurus is the bull charging at Orion. Its face is a V of stars, the Hyades, with orange Aldebaran as the eye, and the Pleiades ride on its back.

  Taurus: the guide · Ian Ridpath, Star Tales: Taurus (opens in a new tab)

• Gemini is two parallel lines of stars, the twins, with their heads marked by two bright stars close together: Castor and Pollux.

  Gemini: the guide · Ian Ridpath, Star Tales: Gemini (opens in a new tab)

• Crux, the Southern Cross, is the smallest of all 88 constellations, and one of the most famous. Its four bright stars make a compact cross, with two brilliant Pointers beside it.

  Crux: the guide · Ian Ridpath, Star Tales: Crux (opens in a new tab)

• Centaurus is a large southern constellation that wraps around the Southern Cross. It holds two of the sky's standouts: Alpha Centauri, the nearest star system, and Omega Centauri, the brightest globular cluster.

  Centaurus: the guide · Ian Ridpath, Star Tales: Centaurus (opens in a new tab)