Stars

1. The remains of a medium mass star, in which the force of gravity is so strong that protons and electrons are fused to form neutrons.
2. When the hydrogen in the core begins to run out, the star begins fusing Helium which generates more energy.
3. A star begins nuclear fusion in its core and generates a lot of energy that pushes outwards, counteracting gravity.
7. A very young star that is still gathering mass from its parent molecular cloud.
8. No nuclear fusion is taking place to support the core, so it is swallowed by its own gravity.
9. The attractive force that pulls atoms together and holds stars together
10. The outer shell is blown away to form a ring around the core.

1. The process in a stars core that makes elements and releases energy
4. The star left at the core of a planetary nebula is extremely dense. It shines with a bright white hot light
5. fusion stops and the iron atoms start to absorb energy. This energy is eventually released in a powerful explosion
6. A large cloud of mostly hydrogen gas or dust in space, pulled together by gravity.