BellaOnline Forums Education Astronomy Constellation or Asterism? *new*

Constellations and asterisms are both patterns of stars. So what is a constellation? And If Saturn is in the constellation Virgo, has it left the Solar System? Why is the Big Dipper an asterism and not a constellation?

Constellation or Asterism

The Summer Triangle is an asterism, because it's a well-known pattern of stars, but is made up of stars from three different constellations.

Here's a picture to show how the Big Dipper (Plough), which is an asterism, fits into the constellation Ursa Major.

BTW does anyone else think it's odd that the Great Bear has such a long tail? Have you ever seen a real bear with one?