Images taken by the Hubble Space Telescope on Feb. 15 have confirmed that Pluto has two small, previously unknown moons. First detected by Hubble last year (SN: 11/5/05, p. 291: New Partners: Hubble finds more moons around Pluto), each moon is only about 50 kilometers across, less than one-hundredth the size of Pluto's giant moon Charon.
One of the bodies lies about 48,000 km from Pluto and the other lies 64,000 km away. In contrast, Charon orbits 19,000 km away from the planet. The February observations rule out the possibility that other similarly small satellites orbit closer to Pluto than either of the new moons do.
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