# Asterism

A recognisable pattern of stars that isn't an official constellation, like the Big Dipper or the Coathanger.

The Big Dipper (the Plough) is part of the constellation Ursa Major; the Summer Triangle spans three constellations; the Coathanger is a little hook of stars in Vulpecula. Asterisms are chance alignments — the stars are usually at very different distances — but they're great signposts for [star hopping](https://astropilot.space/glossary/star-hopping).

**Examples:** [Cr399](https://astropilot.space/object/Cr399.md), [M73](https://astropilot.space/object/M73.md)

**Related:** [Constellation](https://astropilot.space/glossary/constellation.md), [Star hopping](https://astropilot.space/glossary/star-hopping.md), [Open cluster](https://astropilot.space/glossary/open-cluster.md)

From the AstroPilot astronomy glossary: https://astropilot.space/glossary/asterism