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Chapter 10 and 13
Which of the following correctly describes the meaning of albedo?
The higher the albedo, the more light the surface reflects, and the less it absorbs.
Which of the following worlds has the most substantial atmostphere?
Which of the following planets has the least substantial atmosphere?
Which of the following worlds has the greatest difference in temperature between its "no atmosphere" temperature and its actual temperature?
What are greenhouse gases?
gases that absorb infrared light
How does the greenhouse effect work?
Greenhouse gases transmit visible light, allowing it to heat the surface, but then absorb infrared light from Earth, trapping the heat near the surface.
Suppose Earth's atmosphere had no greenhouse gases. Then Earth's average surface temperature would be
250 K, which is well before freezing.
The sky is blue because
molecules scater blue light more effectively than red light.
The first planets around other Sun-like stars were discovered
about a decade ago.
Approximately how many other planetary systems have been discovered to date?
a few hundreds
Which of the following methods has led to the most discoveries of massive planets orbiting near their parent stars?
detecting the gravitational effect of an orbiting planet by loking for the Doppler shifts in the star's spectrum.
Which of the following methods has not yet detected planets around other stars?
detection of reflected light by the planet
Most of the planets discovered around other stars
are more massive than Earth and orbit very close to the star.
How much brighter is a Sun-like star than the reflected light from a planet orbiting around it?
a billion times brighter
By itself, the Doppler technique provides a measure of a planet's
Orbital radius, minimum mass, orbital eccentricity
Planets detected via the Doppler technique have been mostly
Jupiter-mass, in very close orbits.
The composition of a planet can be determined by
The size and shape of a planet's orbit can be determined by
the Doppler technique.
The transit method of planet detection works best for
big planets in edge-on orbits around small stars.
What are the two main differences between extrasolar planetary systems discovered to date and our Solar System?
extrasolar planet orbits tend to be closer and more eccentric than in our Solar System.