Unit 4 Our Galaxy - The Milky Way Flashcards
What is a galaxy?
A large group of stars grouped by gravity.
What is the name of our galaxy?
The Galaxy or The Milky Way.
What are we looking at when we view the Milky Way?
The plane of the galaxy.
What is the disc and how big is it?
The disc is the place where new stars are formed and it is full of dust. The disc contains four spiral arms and the disc is about 30 kpc in diameter and 1-2 kpc thick.
Where is the Solar System in the Milky Way?
The Solar System is in one of the spiral arms of the disc and is about 10 kpc from the nucleus.
What is the nucleus/bulge?
The nucleus/bulge at the centre of the Milky Way and it is believed that there is a massive black hole at the centre.
What is the halo?
The halo of the Milky Way contains mainly globular clusters of relatively old stars in a spherical distribution around the galactic centre.
True or false, we can see the spiral arms of our galaxy.
False. The arms are made of gas and dust which absorbs the light and this prevents us from being able to map our own galaxy, in particular its spiral arms.
