The Orbital Periods of Io, Europa, and Ganymede Are in the Ratio

question 237

Multiple Choice

The orbital periods of Io, Europa, and Ganymede are in the ratio 1:2:4. Is there any significance to this?

• A) No. This is just a random coincidence of the manner in which these satellites condensed out of the primordial nebula around Jupiter.
• B) Yes. This is the ordering predicted by Kepler's third law.
• C) Yes. Combined with the fact that these are all prograde orbits, this shows that these moons are not captured asteroids.
• D) Yes. After completion of an orbit by Ganymede, all these moons will be in a line, creating tidal stresses on Io.

---

Definitions:

Relationship

A connection, association, or involvement between two or more individuals.

Similarity Principle

The tendency for individuals to be attracted to or affiliate with others who are similar to themselves in various aspects.

Heterosexual Couples

Pairs consisting of one male and one female partner, typically in a romantic or sexual relationship.

Homosexual Couples

are romantic partnerships between two individuals of the same sex or gender identity.