Rhea
Saturn's moon Rhea drifts across the face of its parent planet during Cassini's close pass by the icy world on Thursday. Like the Earth and the moon, Rhea always keeps the same side turned toward Saturn.
Rhea is about 1,500 kilometers across, and is made mainly of water ice. Organic compounds can also be found on its rugged surface, seen at the right in one of last week’s close-ups.
September 1, 2007
Riding with Robots:
