Multiple Choice
What causes the apparent retrograde motion of the planets?
A) As Earth passes another planet,its gravitational pull slows down the other planet so that it appears to be traveling backward.
B) When planets are farther from the Sun,they move slower than when they are nearer the Sun;it is during this slower period that they appear to move backwards.
C) The other planets never really appear to move backward;the background stars shift due to Earth's revolution around the Sun.
D) As Earth passes another planet,the other planet appears to move backward with respect to the background stars,but the planet's motion does not actually change.
E) Apparent retrograde motion is an illusion created by turbulence in Earth's atmosphere.
Correct Answer:

Verified
Correct Answer:
Verified
Q95: When we look into the band of
Q96: When someone on Earth observes the Moon
Q97: Answer each of the following questions for
Q98: At midnight it is sometimes possible to
Q99: Suppose the distance to the Moon were
Q101: The point directly over your head is
Q102: Which of the following statements does not
Q103: Consider the following statement,and explain whether or
Q104: Which of the following is not a
Q105: Lunar eclipses are more commonly seen than