Constellations · Observing
Asterism
Say it: ASS-ter-iz-um IPA: /ˈæstərɪzəm/ noun
Asterism: A recognizable pattern of stars that is not itself an officially defined constellation region.
The Big Dipper is an asterism within Ursa Major. Other asterisms draw their stars from several constellations, so familiar sky pictures need not follow official boundaries.
- Example
- The observer used the Big Dipper asterism to find another part of the sky.
- Why astronomers use it
- These patterns make the sky easier to navigate and remember.
- Tiny cosmic connection
- Stars that form a neat pattern from Earth can lie at very different distances.
Observatory Constellations Observing
Where to check it
Written for Cool Moon Facts in its own words; the sources cover the same idea in more depth.