Praxidike (moon)

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Praxidike (prak-sid'-ə-kee, IPA: [prækˈsɪdəki]; Greek Πραξιδίκη), or Jupiter XXVII, is a retrograde irregular satellite of Jupiter. It was discovered by a team of astronomers from the University of Hawaii led by Scott S. Sheppard in 2000, and given the temporary designation S/2000 J 7. Praxidike orbits Jupiter at an average distance of 20,824 Mm in 613.904 days, at an inclination of 144° to the ecliptic (143° to Jupiter's equator), in a retrograde direction and with an eccentricity of 0.1840.

It is named after Praxidike, the Greek goddess of punishment.

Praxidike belongs to the Ananke group, believed to be the remnants of a break-up of a captured heliocentric asteroid.^[1][2] With the estimated diameter of 7 km, Praxidike is the second largest member of the group after Ananke itself (assumed albedo of 0.04)^[3]

The satellite appears grey (colour indices B-V=0.77, R-V= 0.34) characteristic for C-type asteroids.^[4]

[edit] See also

• irregular satellites

[edit] External links

• David Jewiit pages
• Scott Sheppard pages

[edit] References

1. ^ Scott S. Sheppard, David C. Jewitt An abundant population of small irregular satellites around Jupiter, Nature, 423 (May 2003), pp.261-263 (pdf)
2. ^ David Nesvorný, Jose L. A. Alvarellos, Luke Dones, and Harold F. Levison Orbital and Collisional Evolution of the Irregular Satellites, The Astronomical Journal,126 (2003), pages 398–429. (pdf)
3. ^ Scott S. Sheppard, David C. Jewitt, Carolyn Porco Jupiter's outer satellites and Trojans, In: Jupiter. The planet, satellites and magnetosphere. Edited by Fran Bagenal, Timothy E. Dowling, William B. McKinnon. Cambridge planetary science, Vol. 1, Cambridge, UK: Cambridge University Press, ISBN 0-521-81808-7, 2004, p. 263 - 280 (pdf).
4. ^ Grav, Tommy; Holman, Matthew J.; Gladman, Brett J.; Aksnes, Kaare Photometric survey of the irregular satellites,Icarus, 166,(2003), pp. 33-45. Preprint

• Ephemeris (IUA)[1]
• Mean orbital parameters (NASA)[2]