| A | B |
|---|
| constellation | a group of stars that can be seen as a pattern in the night sky |
| binary system | a star group containing 2 stars that revolve around each other |
| multiple star groups | a small star group of 3-4 stars |
| open star cluster | a group of several hundred to a few thousand stars with no particular arrangement |
| globular cluster | a group of several thousand to a million stars that are close to each other and arranged in the shape of a ball |
| galaxy | a huge star system that contains millions or billions of stars |
| Local Group | a group of more than 30 galaxies that includes the Milky Way |
