When the Earth catches up to a slower moving outer planet and passes it like a faster runner overtaking a slower runner in an outside lane, the planet:
A) exhibits retrograde motion
B) slows down because it feels the Earth's gravitational pull
C) decreases in brightness as it passes through the Earth's shadow
D) moves into a more elliptical orbit
E) exhibits prograde motion

Question

Quizplus · Accepted Answer

This phenomenon is known as retrograde motion, where the outer planet appears to move backward in the sky relative to the stars due to the relative positions and motions of Earth and the planet.

When the Earth Catches Up to a Slower Moving Outer