Iocaste (moon)
![]() Iocaste imaged by the Canada-France-Hawaii Telescope in December 2001 | |
| Discovery[1] | |
|---|---|
| Discovered by | Scott S. Sheppard David C. Jewitt Yanga R. Fernandez Eugene A. Magnier |
| Discovery site | Mauna Kea Observatory |
| Discovery date | 23 November 2000 |
| Designations | |
Designation | Jupiter XXIV |
| Pronunciation | /aɪoʊˈkæstiː/ |
Named after | Ιοκάστη Iokástē or Jocasta |
| S/2000 J 3 | |
| Adjectives | Iocastean /ˌaɪoʊkæˈstiːən/[2] |
| Orbital characteristics[3] | |
| Epoch 17 December 2020 (JD 2459200.5) | |
| Observation arc | 24 years 2024-12-03 (last obs) |
| 0.1432617 AU (21,431,650 km) | |
| Eccentricity | 0.3294908 |
| –640.97 d | |
| 289.50565° | |
| 0° 33m 41.927s / day | |
| Inclination | 149.42446° (to ecliptic) |
| 343.53045° | |
| 110.27239° | |
| Satellite of | Jupiter |
| Group | Ananke group |
| Physical characteristics[4] | |
| 5 km | |
| Albedo | 0.04 (assumed) |
Spectral type | C[5] |
| 21,8[6] | |
| 15,5[3] | |
Iocaste, also known as Jupiter XXIV, is a little retrograde irregular satellite of Jupiter.
Discovery and Naming
It was discovered by a team of astronomers from the University of Hawaiʻi 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.[7][1]
It was named in October 2002 after Jocasta,[8] 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.
Orbit
Iocaste orbits Jupiter at an average distance of 21.431.650 in 641 earth days, at an inclination of 149° to the ecliptic with an eccentricity of 0.329. Its orbit is continuously changing due to solar and planetary perturbations.
It belongs to the Ananke group, made up a tightly of irregular retrograde moons orbiting Jupiter at a distance ranging between 19–22 million km, inclinations between 144 and 156°, and eccentricities between 0.10 and 0.30.
Physical characteristics
The satellite is about 5 kilometres in diameter (assumed Albedo 4 %) [9] and appears grey (colour indices B−V=0.63, R−V=0.36), similar to C-type asteroids.[5]
Origin
Iocaste probably did not form near Jupiter but was captured by Jupiter later.Like the other members of the Ananke group, which have similar orbits, Iocaste is probably the remnant of a broken, captured heliocentric asteroid.[10][11]
See also
References
- ^ 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.
- ^ Kin'ya Tsuruta (1996) Shiga Naoya's A Dark Night's Passing, p. 92
- ^ a b "M.P.C. 127087" (PDF). Minor Planet Circular. Minor Planet Center. 17 November 2020.
- ^ "Planetary Satellite Physical Parameters". Jet Propulsion Laboratory. 19 February 2015. Retrieved 26 November 2020.
- ^ a b Grav, T.; Holman, M. J.; Gladman, B. J.; and Aksnes, K.; "Photometric survey of the irregular satellites", Icarus, Volume 166 (2003), pages 33–45
- ^ Sheppard, Scott. "Scott S. Sheppard - Jupiter Moons". Department of Terrestrial Magnetism. Carnegie Institution for Science. Retrieved 26 November 2020.
- ^ Daniel W. E. Green (5 January 2001). "Satellites of Jupiter". International Astronomical Union Central Bureau for Astronomical Telegrams.
- ^ Daniel W. E. Green (22 October 2002). "Comet P/2002 T5 (Linear)". International Astronomical Union Central Bureau for Astronomical Telegrams.
- ^ 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, Volume 1, Cambridge, United Kingsom: Cambridge University Press, ISBN 0-521-81808-7, 2004, pp. 263–280
- ^ Sheppard, S. S.; Jewitt, D. C.; "An Abundant Population of Small Irregular Satellites Around Jupiter" Archived August 13, 2006, at the Wayback Machine, Nature, Volume 423 (May 2003), pages 261–263
- ^ Nesvorný, D.; Alvarellos, J. L. A.; Dones, L.; and Levison, H. F.; "Orbital and Collisional Evolution of the Irregular Satellites", The Astronomical Journal, Volume 126 (2003), pages 398–429
Further reading
- Ephemeris IAU-MPC NSES
- Mean orbital parameters NASA JPL
