Phys 202, Astronomy
Exam 3 Study Guide
  1. Know what is the main parameter that governs where a star will rest on the main sequence and how it will evolve.
  2. Know how the different stellar parameters (mass, surface temperature, size, age/life-time, luminosity) vary along the main sequence.
  3. Know the axes on the H-R diagram, and where to find the main sequence, red giants, and white dwarfs on the diagram.
  4. Know the following about how stars evolve
    1. where does the energy come from that makes a protostar (pre-main-sequence star) shine?
    2. what is happening inside the star when it is on the main sequence?
    3. what is happening inside the star to cause it to become a red giant?
    4. the order of the different evolutionary stages for solar-like stars (protostar, main-sequence stage, red giant stage, helium-core burning stage, red supergiant stage, planetary nebula phase, white dwarf stage)
    5. know roughly how long the different stages last for a solar-mass star and an O or B star
    6. what does helium nuclear burning produce?
  5. Know what happens to the star's core when the outer layers are ejected in a planetary nebula.
  6. Know the approximate mass limits for low and intermediate mass vs. high mass stars, how their evolution differs, and why
  7. Know the kind of matter, the kind of degeneracy pressure, and the mass range allowed in
    1. white dwarfs
    2. neutron stars
    3. black holes
  8. Know how degenerate matter core behaves when more mass is added to it.
  9. Know which element has the lowest energy per nucleon, and therefore is the end of the line for stellar fusion.
  10. Know which kind of object(s) can be left behind after a supernova.
  11. Know the typical mass, mass limits, and radius of
    1. white dwarfs
    2. neutron stars
  12. Know the following about black holes
    1. what is the singularity
    2. what is the event horizon
    3. what is the Schwarzschild radius
    4. what is the relation between Schwarzschild radius and mass of the black hole
  13. Know about gravitational lensing and how gravity affects light. Also know how gravity affects time.
  14. Know the difference between a nova, a Type Ia supernova and a Type II supernova, and what triggers each one.
  15. Know the definition of luminosity, the definition of absolute magnitude, and the difference between absolute and apparent magnitude. You should also know that stars with smaller magnitudes are brighter than stars with higher magnitudes, and that magnitudes can be negative.
  16. Be familiar with stellar parallax and how to convert parallax angles to distance. Also know the approximate limit to the distance of stars for which we can measure parallax.
  17. Learn the following about the star spectral sequence (O, B, A, F, G, K, M)
    1. the letters, in order from hottest to coolest
    2. how the sequence works with letters/numbers, e.g. G5 vs. A2
    3. which stars are hottest, and which are coolest
    4. the luminosity classes (I, II, III, IV, V)