Ophelia is a moon 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.[1] It was not seen again until the Hubble Space Telescope recovered it in 2003.[7][9] Ophelia was named after the daughter of Polonius, Ophelia, in William Shakespeare's play Hamlet. It is also designated Uranus VII.[10]
Discovery[1] | |
---|---|
Discovered by | Richard J. Terrile / Voyager 2 |
Discovery date | January 20, 1986 |
Designations | |
Designation | Uranus VII |
Pronunciation | /oʊˈfiːliə/[2] |
Adjectives | Ophelian /ɒˈfiːliən/[3] |
Orbital characteristics[4] | |
53763.390±0.847 km | |
Eccentricity | 0.00992±0.000107 |
0.37640039±0.00000357 d | |
Average orbital speed | 10.39 km/s[a] |
Inclination | 0.10362°±0.055° (to Uranus' equator)[4] |
Satellite of | Uranus |
Group | ring shepherd |
Physical characteristics | |
Dimensions | 54 × 38 × 38 km[5][note 1] |
~5900 km2[a] | |
Volume | 40800±50.4% km3[6] |
Mass | (3.57±0.32)×1016 kg[6] |
Mean density | 0.87+0.89 −0.30 g/cm3[6] |
~0.003–0.007 m/s2[a] | |
~0.013–0.016 km/s[a] | |
synchronous[5] | |
zero[5] | |
Albedo | 0.065±0.01[7] 0.07[8] |
Temperature | ~65 K[a] |
|
Other than its orbit,[4] size of 54 × 38 km[5] and geometric albedo of 0.065[7] 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 axes of the Ophelia's prolate spheroid is 0.7 ± 0.3.[5]
Ophelia acts as the outer shepherd satellite for Uranus' ε ring.[11] The orbit of Ophelia is within the synchronous orbit radius of Uranus, and is therefore slowly decaying due to tidal forces.[5]