Download Mid Review of Section 2

Review for Quiz 2
Outline of Part 2
• Properties of Stars
 Distances, luminosities, spectral types, temperatures, sizes
 Binary stars, methods of estimating mass, stellar masses
• The HR Diagram
 Spectral type, absolute magnitude, using the HR diagram
• Stellar Evolution (Low Mass and High Mass stars)
 Hydrostatic equilibrium, sources of energy, energy transport
 Evolution in the HR diagram
• Stellar Endpoints
 Planetary nebulae white dwarfs, supernovae, neutron stars
 Black holes
• Binary Star Evolution
 Mass transfer and accretion; novae
• Protostars and Star Formation
The H-R Diagram
Stellar Evolution
• Main Sequence (core H fusion)
Stellar Evolution
• Main Sequence (core H fusion)
• Red Giant (core contraction,
Hydrogen shell burning)
Stellar Evolution
• Main Sequence (core H fusion)
• Red Giant (core contraction,
Hydrogen shell burning)
• Core Helium burning
Stellar Evolution
• Main Sequence (core H fusion)
• Red Giant (core contraction,
Hydrogen shell burning)
• Core Helium burning
• 2nd Giant Branch (core
contraction, H, He shell burning)
Mass Loss Occurs Here
Stellar Evolution
• Main Sequence (core H fusion)
• Red Giant (core contraction,
Hydrogen shell burning)
• Core Helium burning
• 2nd Giant Branch (core
contraction, H, He shell burning)
Mass Loss Occurs Here
If Core is Less Than 1.4 M
• Planetary Nebula (ionization of
mass lost by star)
• White Dwarf (inert C/O core)
Planetary Nebulae
Stellar Evolution
If Core is Greater Than 1.4 M
• Series of core burning and core
contractions
 Carbon to Magnesium, etc.
 Magnesium, etc., to Silicon, etc.
 Silicon, etc. to iron
• SUPERNOVA
Supernova Remnants
Elemental Synthesis
In the supernova explosion,
all the elements are made,
and are ejected into space
Stellar Endpoints
• If Remnant Core is less than 3 M
 Remnant is a Neutron Star
 If Magnetic Pole Points at Earth
 Remnant is a Pulsar
Stellar Endpoints
• If Remnant Core is less than 3 M
 Remnant is a Neutron Star
 If Magnetic Pole Points at Earth
 Remnant is a Pulsar
• If Remnant Core is greater than 3 M
 Remnant is a Black Hole
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The HR Diagram