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Perdita (pronounced /ˈpɜrdɨtə/ PUR-di-tə) is an inner satellite of Uranus. Perdita's discovery was complicated. The first photographs of Perdita were taken by the Voyager 2 spacecraft in 1986, but it was not recognized from the photographs for more than a decade. In 1999, the moon was noticed by Erich Karkoschka and reported.[1][4] But because no further pictures could be taken to confirm its existence, it was officially demoted in 2001.[5] However, in 2003, pictures taken by the Hubble Space Telescope managed to pick up an object where Perdita was supposed to be, finally confirming its existence.[6][7]

Following its discovery in 1999, Perdita was given the temporary designation of S/1986 U 10.[4] It was named after the daughter of Leontes and Hermione in William Shakespeare's play The Winter's Tale. The moon is also designated Uranus XXV.[8]

The moon orbits between Belinda and Puck. The abovementioned Hubble measurements prove that Perdita does not follow a direct Keplerian motion around Uranus. Instead, it is clearly caught in a 43:44 orbital resonance with the nearby moon Belinda. It is also close to an 8:7 resonance with Rosalind.[1][6]

Perdita belongs to Portia Group of satellites, which also includes Bianca, Cressida, Desdemona, Portia, Juliet, Cupid, Rosalind and Belinda.[3] These satellites have similar orbits and photometric properties.[3] Unfortunately, other than its orbit,[1][6] radius of 15 km[1] and geometric albedo of 0.08[3] virtually nothing is known about it.

References

1. ^ a b c d e f g h i j k l Karkoschka, Erich (2001). "Voyager's Eleventh Discovery of a Satellite of Uranus and Photometry and the First Size Measurements of Nine Satellites". Icarus 151: 69–77. doi:10.1006/icar.2001.6597. http://adsabs.harvard.edu/abs/2001Icar..151...69K. edit
2. ^ a b c d e f Calculated on the basis of other parameters
3. ^ a b c d Karkoschka, Erich (2001). "Comprehensive Photometry of the Rings and 16 Satellites of Uranus with the Hubble Space Telescope". Icarus 151: 51–68. doi:10.1006/icar.2001.6596. http://adsabs.harvard.edu/abs/2001Icar..151...51K. edit
4. ^ a b Karkoschka, Erich (May 18 1999). "IAU Circular No. 7171". http://cfa-www.harvard.edu/iauc/07100/07171.html. Retrieved 2006-08-05.
5. ^ Foust, Jeff (December 31 2001). "Moon of Uranus is demoted". Spaceflight Now. http://spaceflightnow.com/news/n0112/31uranusmoon/. Retrieved 2006-08-05.
6. ^ a b c Showalter, Mark R.; Lissauer, Jack J. (2005-12-22). "The Second Ring-Moon System of Uranus: Discovery and Dynamics". Science Express 311 (5763): 973. doi:10.1126/science.1122882. PMID 16373533. http://www.sciencemag.org/cgi/content/abstract/1122882v1.
7. ^ Showalter, M. R.; Lissauer, J. J. (September 3 2003). "IAU Circular No. 8194". http://cfa-www.harvard.edu/iauc/08100/08194.html. Retrieved 2006-08-05.
8. ^ "Planet and Satellite Names and Discoverers". Gazetteer of Planetary Nomenclature. USGS Astrogeology. July 21 2006. http://planetarynames.wr.usgs.gov/append7.html. Retrieved 2006-08-05.