What is an Asterism? Unique Star Patterns Explained

Did you know that many of the familiar star formations you know and love aren't actually constellations? Learn more!

Looking up and finding patterns in the stars is a pastime that’s as old as humanity. The constellations are rich with mythology that has been passed on for millennia.

There are 88 officially recognized constellations. You can probably name some of your favorites: Orion, Andromeda, Cassiopeia … But did you know that many of the familiar star formations you know and love aren’t actually constellations? Well-known “constellations” such as the Big Dipper, Little Dipper, the Teapot, the Northern Cross, and the Summer Triangle are not among the official list. Some, like the Dippers and the Teapot, are actually parts of other constellations (the Big Dipper is part of Ursa Major, the Little Dipper is part of Ursa Minor, and the Teapot is part of Sagittarius). Others, like the Summer Triangle and Winter Hexagon, include stars from several neighboring constellations.

The name for these unofficial constellations is “asterism.” Like constellations, asterisms have a long history. Some are regional, while others are universally recognized. Some are ancient, while others are more modern. If you enjoy stargazing, you may even have a few of your own personal asterisms.

Here’s a list of some of the better-known asterisms:

  • The Belt of Orion: Three bright stars making up “Orion’s Belt.” Also known as the Three Kings or the Rake.
  • The Big Dipper: A popular ladle-shaped asterism within Ursa Major. Also known as the Plough.
  • The Butterfly of Hercules: A butterfly-shaped asterism within Hercules.
  • The Butterfly of Orion: A butterfly-shaped asterism within Orion.
  • The Coat Hanger: An asterism in Vulpecula, shaped like a line with a hook coming out of the center.
  • The Circlet: A round asterism within Pisces.
  • The Diamond of Virgo: A diamond-shaped asterism within Virgo.
  • The False Cross: A cross-shaped asterism made up of stars from Carina and Vela.
  • The Fish Hook: A J-shaped asterism located in Scorpius.
  • The Golf Putter: A long chain of stars with that form a golf club shape within Andromeda.
  • The Great Square: A Square-shaped asterism made up of stars from Pegasus and Andromeda.
  • The Kite: A diamond-shaped asterism within Boötes.
  • The Keystone: An uneven rectangle within Hercules.
  • The Little Dipper: Similar to the Big Dipper, only smaller, the Little Dipper is a ladle-shaped asterism within Ursa Minor.
  • The Northern Cross: A cross-shaped asterism within Cygnus.
  • The Northern Fly: A small triangular asterism near the flank of Aries.
  • The Pleiades: An open cluster of bright stars within Taurus. Also known as the Seven Sisters.
  • The Sail: A sail-shaped asterism within Corvus.
  • The Sickle: A curved asterism within Leo.
  • The Summer Triangle: A popular asterism made up of stars from Altair, Deneb, and Vega.
  • The Teapot: A popular asterism within Sagittarius.
  • The Trapezoid: A trapezoid-shaped asterism within Boötes.
  • The “W” of Cassiopeia: A letter “W” within Cassiopeia.
  • The Water Jar: An asterism within Aquarius.
  • The Winter Hexagon: A large, irregularly-shaped hexagon made up of parts Canis Major, Canis Minor, Auriga, Taurus, Orion, and Gemini.
  • The Winter Triangle: A popular asterism within the Winter Hexagon, made up from parts of Canis Major, Canis Minor, and Orion.
  • The “Y” of Virgo: A letter “Y” within Virgo.
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Jaime McLeod

Jaime McLeod is a longtime journalist who has written for a wide variety of newspapers, magazines, and websites, including MTV.com. She enjoys the outdoors, growing and eating organic food, and is interested in all aspects of natural wellness.

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llev

The history we know to be appreciated is our own curiossity, and it makes up our viewpoint with the constellations and there stars. This is very interesting to be able to see them, and know there other names and objects.

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