Iocaste (moon)

Iocaste
	Iocaste imaged by the Canada-France-Hawaii Telescope in December 2001
Discovery
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
Alternative names	S/2000 J 3
Adjectives	Iocastean /ˌaɪoʊkæˈstiːən/
Orbital characteristics
	Epoch 17 December 2020 (JD 2459200.5)
Observation arc	17.39 yr (6,350 days)
Semi-major axis	0.1432617 AU (21,431,650 km)
Eccentricity	0.3294908
Orbital period (sidereal)	–640.97 d
Mean anomaly	289.50565°
Mean motion	0° 33m 41.927s / day
Inclination	149.42446° (to ecliptic)
Longitude of ascending node	343.53045°
Argument of perihelion	110.27239°
Satellite of	Jupiter
Group	Ananke group
Physical characteristics
Mean diameter	5 km
Albedo	0.04 (assumed)
Spectral type	C
Apparent magnitude	21,8
Absolute magnitude (H)	15,5

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]

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 ^{[dead link]}

v t e Moons of Jupiter
Listed in increasing approximate distance from Jupiter
Inner moons	Metis Adrastea Amalthea Thebe
Galilean moons	Io Europa Ganymede Callisto
Themisto	Themisto
Himalia group (9)	Leda Ersa S/2018 J 2 Himalia Pandia Lysithea Elara S/2011 J 3 Dia
Carpo group (2)	S/2018 J 4 Carpo
Valetudo	Valetudo
Ananke group (27)	Euporie Jupiter LV Eupheme S/2021 J 3 Jupiter LII Jupiter LIV Mneme Euanthe S/2003 J 16 Harpalyke Orthosie Helike S/2021 J 2 Praxidike Jupiter LXIV S/2021 J 1 S/2003 J 12 Jupiter LXVIII Thelxinoe Thyone S/2003 J 2 S/2022 J 3 Ananke Iocaste S/2017 J 10 Hermippe Jupiter LXX
Carme group (31)	S/2016 J 3 S/2022 J 1 Jupiter LXIX Pasithee S/2021 J 6 S/2003 J 24 Chaldene Jupiter LXIII Isonoe S/2017 J 11 Kallichore S/2021 J 4 Erinome Kale Eirene Aitne Eukelade S/2022 J 2 Arche Taygete Jupiter LXXII Carme Herse Jupiter LXI Jupiter LI S/2003 J 9 Jupiter LXVI Kalyke S/2003 J 10 S/2018 J 3 S/2021 J 5
Pasiphae group (18)	Philophrosyne Eurydome Jupiter LVI S/2003 J 4 S/2016 J 4 Jupiter LXVII Hegemone Pasiphae Sponde Megaclite Cyllene Sinope Jupiter LIX Aoede Autonoe Callirrhoe S/2003 J 23 Kore
See also	Rings of Jupiter Jupiter's moons in fiction
Category

Discovery and Naming

Orbit

Physical characteristics

Origin

See also

References

Further reading