The Universe and Cosmology
Galaxies and stars form from gases (mainly H) pulled together by gravity
- Stars produce energy from nuclear fuel
Death of a star
- Collapse when fuel runs out
- Becomes a dwarf, neutron star (pulsar) or black hole
- Rapid collapse causes a supernova
The Universe is Expanding
- Hubble (1929) Measured by “Doppler Shift”
- Expanding in all directions as if it came from a point
- Estimate for age of universe ~ 15 billion years
Future?
- Expansion, gradual slowing, or collapse to the BIG CRUNCH