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Phoebe ("FEE bee") is the outermost of Saturn's known satellites. Phoebe is almost 4 times more distant from Saturn than its nearest neighbor (Iapetus).
orbit: 12,952,000 km from Saturn diameter: 220 km mass: 4.0e18 kg
Phoebe is the daughter of Uranus and Gaia; grandmother of Apollo and Artemis.
Discovered by Pickering in 1898.
On June 11, 2004 Cassini passed close to Phoebe on its way into the Saturn system, giving us our first real look at it since Voyager and at much higher resolution.
Most of Saturn's moons are bright but Phoebe's albedo is very low (.05), as dark as lampblack.
All of Saturn's moons except for Phoebe and Iapetus orbit very nearly in the plane of Saturn's equator. Phoebe's orbit is inclined almost 175° (its north pole is in the opposite direction to Saturn's).
Phoebe's eccentric, retrograde orbit and unusual albedo indicates that it may be a captured asteroid or Kuiper Belt object.
Phoebe is also unusual in that it does not rotate synchronously as do all the other moons of Saturn except Hyperion.
Material knocked off of Phoebe's surface by microscopic meteor impacts may be responsible for the dark surfaces of Hyperion and the leading hemisphere of Iapetus.