2. Describe the three main layers of the solar atmo-
sphereand how you would best observe them.
7. How do astronomers detect the presence of a
magnetic field in hot gases, such as the field in the solar
12. Why do thermonuclear reactions in the Sun take
placeonly in its core?
The Temperatures of Stars
3. .Measurements of a binary star system are required
todetermine what property of stars? a. Luminosity,
b. Apparent magnitude, c. distance, d. mass, e. temperature
10. whatis the difference between apparent magni-
tude and absolute magnitude?
20. Draw an H-R diagram and sketch the regions
occupied by main-sequence stars, giants, supergiant’s,
andwhite dwarfs. Briefly discuss the different ways you
couldhave labeled the axes of your graph.
3. What is the source of energy that enables a main-
Sequence star to shine? a. Friction between its atoms,
b. Fusion of hydrogen in a shell that surrounds the
Core, c. Fusion of helium in its core, d. Fusion of hydro-
Genin its core, e. Burning on its surface
6. whydo thermonuclear reactions not occur on the
Surface of a main-sequence star?
13.What does it mean when an astronomer says that
astar “moves” from one place to another on an H-R
3. What prevents a neutron star from collapsing?
a. Hydrogen fusion, b. friction, c. electron degeneracy
Pressure, d. neutron degeneracy pressure, e. helium fusion
7. whatis a planetary nebula, and how does it form?
12.What is the Oppenheimer-Volkov limit?
3 .which feature is found with Kerr black holes but not Schwarzschild black holes? a. a singularity, b. an event horizon, c. gravitational redshift of photons outside of the black hole, d. an ergo region, e. warping of nearby space time
10. If light cannot escape from a black hole, how can we detect X rays from such an object?