What is the order of rotation periods for the Galilean moons, from shortest to longest? (Hint: All four moons are in synchronous orbits.)
A) Io, Europa, Ganymede, Callisto
B) Io, Ganymede, Europa, Callisto
C) Ganymede, Europa, Io, Callisto
D) Callisto, Ganymede, Europa, Io

Question

Quizplus · Accepted Answer

The Galilean moons, in order of increasing distance from Jupiter, are Io, Europa, Ganymede, and Callisto. Because they are in synchronous orbits, their rotation periods match their orbital periods around Jupiter. Thus, the closer a moon is to Jupiter, the shorter its rotation period, making the correct order from shortest to longest: Io, Europa, Ganymede, Callisto.

What Is the Order of Rotation Periods for the Galilean