Prometheus is a shepherd moon of which planet?

• A. Saturn
• B. Jupiter
• C. Uranus
• D. Neptune

Answer: (A)

Prometheus is a shepherd moon, meaning its gravity helps shape and confine a planet’s rings. It orbits Saturn near the F ring and, along with Pandora, tugs on ring particles to keep the ring’s edge sharp and defined. That relationship between a small moon and a planet’s rings is a hallmark of Saturn, whereas the other planets listed don’t host this moon. So the planet associated with Prometheus is Saturn.