Ophelia (moon)
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- There is also an asteroid called 171 Ophelia.
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Discovery
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| Discovered by | Richard J. Terrile / Voyager 2 |
| Discovery date | January 20, 1986 |
| Mean orbit radius | 53,763.390 ± 0.847 km[1] |
| Eccentricity | 0.00992 ± 0.000107[1] |
| Orbital period | 0.37640039 ± 0.00000357 d[1] |
| Inclination | 0.10362 ± 0.055° (to Uranus' equator)[1] |
| Satellite of | Uranus |
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Physical characteristics
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| Dimensions | 54 × 38 × 38 km[2] |
| Mean radius | 23 ± 4 km[2] |
| Surface area | ~6600 km²[3] |
| Volume | ~41,000 km³[3] |
| Mass | ~5.1×1016 kg[3] |
| Mean density | ~1.3 g/cm³ assumed |
| Equatorial surface gravity | ~0.0070 m/s2[3] |
| Escape velocity | ~0.018 km/s[3] |
| Rotation period | synchronous[2] |
| Axial tilt | zero[2] |
| Albedo | 0.08 ± 0.01 [4] |
| Temperature | ~64 K[3] |
Ophelia (oe-fee'-lee-ə, IPA: /ɔʊˈfiːliə/) is an inner satellite of Uranus. It was discovered from the images taken by Voyager 2 on January 20, 1986, and was given the temporary designation S/1986 U 8.[5] It was not seen until the Hubble Space Telescope recovered it in 2003.[4][6] Ophelia was named after the daughter of Polonius, Ophelia, in William Shakespeare's play Hamlet. It is also designated Uranus VII.[7]
Unfortunately, other than its orbit,[1] radius of 23 km[2] and geometric albedo of 0.08[4] virtually nothing is known about it. At the Voyager 2 images Ophelia appears as an elongated object, the major axis pointing towards Uranus. The ratio of axises of the Ophelia's prolate spheroid is 0.7 ± 0.3.[2]
Ophelia acts as the outer shepherd satellite for Uranus' Epsilon ring.[8] The orbit of Ophelia is within the synchronous orbit radius of Uranus, and therefore the moon is slowly decaying due to tidal forces.[2]
[edit] References
- ^ a b c d e Jacobson, R.A. (1998). "The Orbits of the Inner Uranian Satellites From Hubble Space Telescope and Voyager2 Observations". The Astronomical Journal 115: 1195-1199. doi:.
- ^ a b c d e f g 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:.
- ^ a b c d e f Calculated on the basis of other parameters
- ^ a b c Karkoschka, Erich (2001). "Comprehensive Photometry of the Rings and 16 Satellites of Uranus with the Hubble Space Telescope". Icarus 151: 51–68. doi:.
- ^ Smith, B. A. (January 27 1986). IAU Circular No. 4168. Retrieved on 2006-08-05.
- ^ Showalter, M. R.; Lissauer, J. J. (September 3 2003). IAU Circular No. 8194. Retrieved on 2006-08-05.
- ^ Planet and Satellite Names and Discoverers. Gazetteer of Planetary Nomenclature. USGS Astrogeology (July 21 2006). Retrieved on 2006-08-05.
- ^ Esposito, L. W. (2002). "Planetary rings". Reports On Progress In Physics 65: 1741–1783.
[edit] External links
Ophelia Profile by NASA's Solar System Exploration
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