Of the planetary systems that may exist in our galaxy, what fraction may contain a habitable planet?
A) almost all
B) about half
C) about a tenth
D) only 1 in 50
E) less than 1 in 100
Question 2How was the rotation rate of Jupiter's core determined?
A) by observing the Great Red Spot
B) by watching Io move across the disk of Jupiter
C) by radio observations of Jupiter's rapidly spinning magnetosphere
D) by observing the fastest moving regions of Jupiter's equator
E) by measuring the oblateness of Jupiter's disk
Question 3What is seeing?
A) a measure of the quality of the telescope's optics
B) a measure of the transparency of the scope's objective lens
C) a measurement of the sharpness of vision of the astronomer's eyes
D) a measurement of the image quality due to air stability
E) a measurement of clarity and absence of clouds
Question 4Which of the following best explains why we can rule out the idea that planets are usually formed by near-collisions between stars?
A) Studies of the trajectories of nearby stars relative to the Sun show that the Sun is not in danger of a near-collision with any of them.
B) Stellar near-collisions are far too rare to explain all the planets now known to orbit nearby stars.
C) A near collision might have created planets, but it could not have created moons, asteroids, or comets.
D) A near collision should have left a trail of gas extending out behind the Sun, and we see no evidence of such a trail.
Question 5Which of the following are irregularities in our solar system that must be explainable in models of planetary formation?
A) Venus' low rate of rotation
B) Mars' north-south asymmetry
C) the tilt of Uranus' rotation axis
D) binary Kuiper Belt objects
E) All of the above