Cordelia (moon)

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For the asteroid of the same name, see 2758 Cordelia.
Cordelia'
Discovery
Discovered by Richard J. Terrile / Voyager 2
Discovery date January 20, 1986
Mean orbit radius 49751.722 ± 0.149 km[1]
Eccentricity 0.00026 ± 0.000096[1]
Orbital period 0.33503384 ± 0.00000058 d[1]
Inclination 0.08479 ± 0.031° (to Uranus' equator)[1]
Satellite of Uranus
Physical characteristics
Dimensions 50 × 36 × 36 km[2]
Mean radius 21 ± 3 km[2]
Surface area ~5500 km²[3]
Volume ~38,900 km³[3]
Mass ~5.0×1016 kg[3]
Mean density ~1.3 g/cm³ assumed
Equatorial surface gravity ~0.0073 m/s²[3]
Escape velocity ~0.017 km/s[3]
Rotation period synchronous[2]
Axial tilt zero[2]
Albedo 0.08 ± 0.01 [4]
Temperature ~64 K[3]
Discovery image of Cordelia
Discovery image of Cordelia

Cordelia (kor-dee'-lee-ə, IPA: /kɔrˈdiːliə/) is the innermost 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 7.[5] It was not detected again until the Hubble Space Telescope observed it in 1997.[4][6] Cordelia takes its name from the youngest daughter of Lear in William Shakespeare's King Lear. It is also designated Uranus VI.[7]

Unfortunately, other than its orbit,[1] radius of 21 km[2] and geometric albedo of 0.08[4] virtually nothing is known about it. At the Voyager 2 images Cordelia appears as an elongated object, the major axis pointing towards Uranus. The ratio of axises of the Cordelia's prolate spheroid is 0.7 ± 0.2.[2]

Cordelia acts as the inner shepherd satellite for Uranus' Epsilon ring.[8] Cordelia's orbit is within Uranus' synchronous orbit radius, and is therefore slowly decaying due to tidal deceleration.[2]


[edit] References

  1. ^ 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:10.1086/300263. 
  2. ^ 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:10.1006/icar.2001.6597. 
  3. ^ a b c d e f Calculated on the basis of other parameters
  4. ^ 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:10.1006/icar.2001.6596. 
  5. ^ Smith, B. A. (January 27, 1986). IAU Circular No. 4168. Retrieved on 2006-08-06.
  6. ^ Showalter, M. R.; Lissauer, J. J. (September 3 2003). IAU Circular No. 8194. Retrieved on 2006-08-05.
  7. ^ Planet and Satellite Names and Discoverers. Gazetteer of Planetary Nomenclature. USGS Astrogeology (July 21, 2006). Retrieved on 2006-08-06.
  8. ^ Esposito, L. W. (2002). "Planetary rings". Reports On Progress In Physics 65: 1741–1783. 

[edit] External links

Cordelia Profile by NASA's Solar System Exploration