Resonance

Definition

Resonance is a gravitational interaction where two orbiting bodies exert regular, periodic gravitational influences on each other, usually due to their orbital periods being in a ratio of small integers. This phenomenon often stabilizes the orbits of moons and planetary rings.

5 Must Know Facts For Your Next Test

1. An example of resonance is the 2:1 mean motion resonance between Enceladus and Dione, which helps maintain Enceladus's geothermal activity.
2. Resonances can clear gaps in planetary rings, such as the Cassini Division in Saturn's rings caused by Mimas' resonance.
3. Orbital resonances contribute to ring particle shepherding, maintaining sharp edges within planetary rings.
4. In Pluto's system, Charon is in a 1:1 spin-orbit resonance with Pluto.
5. Resonant interactions can lead to increased orbital eccentricity or inclination, affecting the structure and behavior of moons and rings.

Review Questions

• What is an example of a moon-moon resonance in our solar system?
• How does resonance affect the structure of Saturn's rings?
• What role does resonance play in maintaining Enceladus's geothermal activity?

Related terms

Shepherd Moon: A moon that helps to keep a planetary ring stable through its gravitational influence.

Mean Motion Resonance: A type of orbital resonance where two bodies have orbital periods that are simple integer ratios.

Cassini Division:

A gap between Saturn's A and B rings caused by gravitational influences from Mimas.