The Life of Stars and Galaxies
Galaxies form from clouds of gasses (mainly hydrogen) pulled together by gravity
- How do we know what galaxies stars are made of?
- Atomic spectral lines! Just like here on earth!
Stars form from condensation of gasses within a galaxy due to the pull of gravity
- Start to “burn” nuclear fuel when they become so dense and hot that nuclei fuse and release energy
- Our sun is fueled by burning hydrogen (proton) and deuterium (proton + neutron) to form helium nuclei
- Other elements formed in larger stars and the heavy elements are formed in a Supernova ! (More later)
- We are the remnants of supernovae !