Iocaste (moon)

Iocaste, also known as Jupiter XXIV, is a retrograde irregular satellite of Jupiter. It was discovered by a team of astronomers from the University of Hawaii including: David C. Jewitt, Yanga R. Fernandez, and Eugene Magnier led by Scott S. Sheppard in 2000, and given the temporary designation S/2000 J 3.[6][1]

Iocaste imaged by the Canada-France-Hawaii Telescope in December 2001
Discovery [1]
Discovered byScott S. Sheppard
David C. Jewitt
Yanga R. Fernandez
Eugene A. Magnier
Discovery siteMauna Kea Observatory
Discovery date23 November 2000
Jupiter XXIV
Named after
Ιοκάστη Iokástē or Jocasta
S/2000 J 3
AdjectivesIocastean /ˌkæˈstən/[2]
Orbital characteristics[3]
Epoch 17 December 2020 (JD 2459200.5)
Observation arc17.39 yr (6,350 days)
0.1432617 AU (21,431,650 km)
–640.97 d
0° 33m 41.927s / day
Inclination149.42446° (to ecliptic)
Satellite ofJupiter
GroupAnanke group
Physical characteristics[5]
Mean diameter
5 km
Mean radius
1.6 miles (2.6 km)
Albedo0.04 (assumed)

Iocaste orbits Jupiter at an average distance of 20.723 million kilometers in 632 earth days, at an inclination of 147° to the ecliptic (146° to Jupiter's equator) with an eccentricity of 0.2874.

It was named in October 2002 after Jocasta,[7] the mother/wife of Oedipus in Greek mythology. The name ending in "e" was chosen in accordance with the International Astronomical Union's policy for designating outer moons with retrograde orbits.

Iocaste belongs to the Ananke group, believed to be the remnants of a break-up of a captured heliocentric asteroid.[8][9]

The satellite is about 5 kilometres in diameter[10] and appears grey (colour indices B−V=0.63, R−V=0.36), similar to C-type asteroids.[11]

See alsoEdit


  1. ^ a b Brian G. Marsden (5 January 2001). "S/2000 J 2, S/2000 J 3, S/2000 J 4, S/2000 J 5, S/2000 J 6". International Astronomical Union Minor Planet Center.
  2. ^ Kin'ya Tsuruta (1996) Shiga Naoya's A Dark Night's Passing, p. 92
  3. ^ a b "M.P.C. 127087" (PDF). Minor Planet Circular. Minor Planet Center. 17 November 2020.
  4. ^ Sheppard, Scott. "Scott S. Sheppard - Jupiter Moons". Department of Terrestrial Magnetism. Carnegie Institution for Science. Retrieved 26 November 2020.
  5. ^ "Planetary Satellite Physical Parameters". Jet Propulsion Laboratory. 19 February 2015. Retrieved 26 November 2020.
  6. ^ Daniel W. E. Green (5 January 2001). "Satellites of Jupiter". International Astronomical Union Central Bureau for Astronomical Telegrams.
  7. ^ Daniel W. E. Green (22 October 2002). "Comet P/2002 T5 (Linear)". International Astronomical Union Central Bureau for Astronomical Telegrams.
  8. ^ Sheppard, S. S.; Jewitt, D. C.; "An Abundant Population of Small Irregular Satellites Around Jupiter" Archived August 13, 2006, at the Wayback Machine, Nature, Vol. 423 (May 2003), pp. 261–263
  9. ^ Nesvorný, D.; Alvarellos, J. L. A.; Dones, L.; and Levison, H. F.; "Orbital and Collisional Evolution of the Irregular Satellites", The Astronomical Journal, Vol. 126 (2003), pp. 398–429[dead link]
  10. ^ Sheppard, S. S.; Jewitt, D. C.; Porco, C. C.; "Jupiter's Outer Satellites and Trojans" Archived June 14, 2007, at the Wayback Machine, in Jupiter: The Planet, Satellites and Magnetosphere, edited by Fran Bagenal, Timothy E. Dowling, and William B. McKinnon, Cambridge Planetary Science, Vol. 1, Cambridge, UK: Cambridge University Press, ISBN 0-521-81808-7, 2004, pp. 263–280
  11. ^ Grav, T.; Holman, M. J.; Gladman, B. J.; and Aksnes, K.; "Photometric survey of the irregular satellites", Icarus, Vol. 166 (2003), pp. 33–45

Further readingEdit