Stars How Do We Know what they are?
The Electromagnetic Spectrum
- Visible Light
- Solar Spectrum
- Stellar Spectrum
Classification of Stars
The HR Diagram
- Absolute Magnitude or Luminosity Vs Spectral Type/Temperature/Color
Evolution of a 1 solar mass star (Sun)
- Nebula
- T-Tauri
- Main Sequence
- Red Giant
- Nova
- White Dwarf (C-N-O)
Evolution of a 5 - 8 solar mass star
- Carbon Star explodes (fusion stops at C-N-O)
- No remnant
Evolution of a 8 - 80 solar mass star (Super Giant)
- Shell detonation
- blows off envelope
- leaves collapsed core
- Either a neutron star, or a Black Hole
- Fe Fusion adsorbs energy
- The Star collapses
- Super Novas
- Some heavy elements beyond Fe (Iron)
Form during the Super Nova
End Points
- White Dwarfs
- Neutron Stars
- Black Holes
Celestial Sign Posts in the Summer Sky
8 - 12 pm, in August