Juliet (moon)

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There is also an asteroid called 1285 Julietta.
Juliet
Discovery
Discovered by Stephen P. Synnott / Voyager 2
Discovery date January 3, 1986
Semi-major axis 64,358.222 ± 0.048 km[1]
Eccentricity 0.00066 ± 0.000087[1]
Orbital period 0.493065490 ± 0.000000012 d[1]
Inclination 0.06546 ± 0.040° (to Uranus' equator)[1]
Satellite of Uranus
Physical characteristics
Dimensions 150 × 74 × 74 km[2]
Mean radius 53 ± 4 km[2]
Surface area ~35,000 km²[3]
Volume ~632,000 km³[3]
Mass ~8.2×1017 kg[3]
Mean density ~1.3 g/cm³ assumed
Equatorial surface gravity ~0.016 m/s2[3]
Escape velocity ~0.040 km/s[3]
Rotation period synchronous[2]
Axial tilt zero[2]
Albedo 0.08 ± 0.01[4]
Temperature ~64 K[3]
Discovery image of Juliet
Discovery image of Juliet

Juliet (jew'-lee-ət, IPA: /ˈdʒuliət/, or jew'-lee-et', /ˌdʒuliˈɛt/) is an inner satellite of Uranus. It was discovered from the images taken by Voyager 2 on 1986-01-03, and was given the temporary designation S/1986 U 2.[5] It is named after the heroine of William Shakespeare's play Romeo and Juliet. It is also designated Uranus XI.[6]

Juliet belongs to Portia Group of satellites, which also includes Bianca, Cressida, Desdemona, Portia, Rosalind, Cupid, Belinda and Perdita.[4] These satellites have similar orbits and photometric properties.[4] Unfortunately, other than its orbit,[1] radius of 53 km[2] and geometric albedo of 0.08[4] virtually nothing is known about it.

At the Voyager 2 images Juliet appears as an elongated object, the major axis pointing towards Uranus. The ratio of axises of the Juliet's prolate spheroid is 0.5 ± 0.3, which is rather an extreme value.[2] Its surface is grey in color.[2]

Juliet may collide with Desdemona within the next 100 million years.[7]

[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 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. 
  5. ^ Smith, B. A. (January 16 1986). IAU Circular No. 4164. Retrieved on 2006-08-06.
  6. ^ Planet and Satellite Names and Discoverers. Gazetteer of Planetary Nomenclature. USGS Astrogeology (July 21 2006). Retrieved on 2006-08-06.
  7. ^ Duncan, Martin J.; Jack J. Lissauer (1997). "Orbital Stability of the Uranian Satellite System". Icarus 125 (1): 1-12. doi:10.1006/icar.1996.5568. 

[edit] External links