Galactic disc

A galactic disc is like a very big, round frisbee of stars, planets, and other things that spins around in space around the center of the galaxy. All the galaxies we can see in the night sky have galactic discs. Inside the galactic disc, there is a bright group of stars called the bulge. The bulge is made up of hundreds of billions of stars, held together by their own gravity. The Sun and planets live in a part of the Milky Way called the Orion-Cygnus arm, which is a part of the Milky Way's galactic disc.