Praxidike (moon)

Praxidike (pron-en|prækˈsɪdɨki "prak-SID-ə-kee," or as in Greek "Πραξιδίκη)," also known as nowrap|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, [ [http://cfa-www.harvard.edu/iauc/07500/07555.html IAUC 7555: "Satellites of Jupiter"] 2001 January 5 (discovery)] [ [http://cfa-www.harvard.edu/mpec/K01/K01A29.html MPEC 2001-A29: "S/2000 J 7, S/2000 J 8, S/2000 J 9, S/2000 J 10, S/2000 J 11"] 2001 January 15 (discovery and ephemeris)] and given the temporary designation nowrap|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 was named in August 2003 after Praxidike, [ [http://cfa-www.harvard.edu/iauc/07900/07998.html IAUC 7998: "Satellites of Jupiter"] 2002 October 22 (naming the moon)] 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.Sheppard, S. S., Jewitt, D. C.; [http://www.ifa.hawaii.edu/~jewitt/papers/JSATS/SJ2003.pdf "An Abundant Population of Small Irregular Satellites Around Jupiter"] , Nature, Vol. 423 (May 2003), pp. 261-263] Nesvorný, D.; Alvarellos, J. L. A.; Dones, L.; and Levison, H. F.; [http://www.journals.uchicago.edu/AJ/journal/issues/v126n1/202528/202528.web.pdf "Orbital and Collisional Evolution of the Irregular Satellites"] , The Astronomical Journal, Vol. 126 (2003), pp. 398–429] With an estimated diameter of 7 km, Praxidike is the second largest member of the group after Ananke itself (assumed albedo of 0.04)Sheppard, S. S.; Jewitt, D. C.; Porco, C.; [http://www.ifa.hawaii.edu/~jewitt/papers/JUPITER/JSP.2003.pdf "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, pp. 263-280]

The satellite appears grey (colour indices B-V=0.77, R-V= 0.34) characteristic for C-type asteroids.Grav, T.; Holman, M. J.; Gladman, B. J.; Aksnes, K.; [http://arxiv.org/abs/astro-ph/0301016 "Photometric Survey of the Irregular Satellites"] , Icarus, Vol. 166 (2003), pp. 33-45]

ee also

*Irregular satellites

References

#

Ephemeris [http://cfa-www.harvard.edu/iau/NatSats/NaturalSatellites.html IAU-MPC NSES]
#Mean orbital parameters [http://ssd.jpl.nasa.gov/?sat_elem NASA JPL]

External links

* [http://www.ifa.hawaii.edu/~jewitt/irregulars.html David Jewitt pages]
* [http://www.ifa.hawaii.edu/~sheppard/satellites/urasatdata.html Scott Sheppard pages]