Prometheus

Prometheus is one of Saturn's moons, designated as XVI. It orbits Saturn at a mean distance of 139,380 km with an orbital period of 0.603 Earth days. Prometheus is one of Saturn's smaller moons, with dimensions of approximately 70 × 50 × 34 km and a mass of 1.59 × 10^17 kg.1

Prometheus, along with the moon Pandora, is known as a shepherd moon. These moons orbit near the F ring of Saturn and influence its structure through gravitational interactions. Prometheus, as the inner shepherd, pushes ring particles outward while itself moving inward, and Pandora, the outer shepherd, does the opposite. This shepherding effect helps to confine the ring particles to a narrow band.2