Astronomy part 5

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Astronomy part 5
2015-04-21 21:37:46
Astronomy part
test 3
Show Answers:

  1. What is an "extrasolar planet"?
    a planet that orbits a star that is not our own Sun
  2. In essence, the Kepler mission is searching for extrasolar planets by
    monitoring stars for slight dimming that might occur as unseen planets pass in front of them
  3. How can gravitational tugs from orbiting planets affect the motion of a star?
    The planet and the star both make orbits about a common center of mass. The star, being much larger than the planet, has a much smaller orbit. But it does move slightly.
  4. Explain how alien astronomers could deduce the existence of planets in our solar system by observing the Sun's motion
    • -They could measure the small changes in position of the Sun to deduce the presence of our planets.
    • -They could measure the small velocity changes of the Sun to deduce the presence of our planets.
  5. If we can measure the period of a star's "wobble" caused by an orbiting planet, we know the
    period of the planet's orbit.
  6. Why are planets with long orbital periods among the last to be discovered?
    Astronomers have to watch a long time before they repeat their orbits
  7. What was so surprising about the first extrasolar planets that they forced a change in our theory of planet formation?
    They were massive like Jupiter, but very close to their host star.
  8. What's the best explanation for the location of hot Jupiters?
    They formed farther out like Jupiter but then migrated inward.
  9. In general, what kind of terrestrial planet would you expect to have the thickest lithosphere?
    a small planet