A pale and icy moon of the planet Saturn, whose
diameter of 1,500 km makes it that planet's
second largest satellite, after Titan. Rhea is the outermost of five moons that
orbit close to their parent planet, with
the others being Dione, Tethys, Enceladus and, closest of all to Saturn, Mimas. Beyond
Rhea are some 700,000 km of empty space before the orbit of the next
moon, mighty Titan itself.