Quiz 4

  1. How long does it take for photons to get to Earth from a solar flare eruption?
    8 minutes
  2. In a solar prominence or filament, what lifts the gas into an arch above the photosphere?
    The Sun's magnetic field
  3. How many times stronger than Earth's is the magnetic field of a sunspot?
    5000 x
  4. What property of the Sun do we learn by measuring Zeeman's effect on the Sun's spectral lines?
  5. What is the rotation period of the Sun near the Equator? At 75o latitude?
    25 days; 33 days
  6. What is the temperature of a sunspot umbra? Is it hotter or cooler than the Photosphere?
    4300 K; cooler
  7. What is the length (in years) of the average ncycle in the number of sunspots?
    11 years
  8. What do we call the minor amount of the Sun's gases that escape outward into space?
    Solar Wind
  9. Which of the Sun's three atmospheric layers is the coolest? The densest?
    Chromosphere; Photosphere
  10. What is the approximate temperature of the solar corona? What heats it to this temperature?
    1 million K; heated by energy carried aloft and released by the Sun's magnetic fields
  11. In the bright center of a granule, which way is the gas moving?
    upward, by convection
  12. How long does a convective granule on the photosphere last?
    several minutes
  13. What is the photosphere and how thick is it? What percentage of the Sun's total radius is this?
    A thin layer of gas on the surface of the Sun; 0.01% as thick as the air
  14. What is the formal definition of a planet?
    • A celestial body that is:
    • 1. In orbit around the sun
    • 2. Has sufficent mass for its self-gravity to pull itself into a nearly spheical shape
    • 3. has cleared the neighborhood around its orbit
  15. What is a dwarf planet?
    • 1. In orbit around the sun
    • 2. does not have enough gravity to clear is orbital neighborhood of debris
  16. All objects in the solar system that are not planets, dwarf planets, or moons
    small solar bodies (SSBs)
Card Set
Quiz 4
Astronomy- Georgia State