Pasiphae (moon)
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Pasiphae Template:IPAc-en, formerly spelled Pasiphaë,<ref>Template:Cite web</ref> is a retrograde irregular satellite of Jupiter. It was discovered in 1908 by Philibert Jacques Melotte<ref name="Melotte 1908">Template:Cite journal</ref><ref name="Harvard 1908">Template:Cite journal</ref> and later named after the mythological Pasiphaë, wife of Minos and mother of the Minotaur from Greek legend.
The moon was first spotted on a plate taken at the Royal Greenwich Observatory on the night of 28 February 1908. Inspection of previous plates found it as far back as January 27. It received the provisional designation Template:Nowrap, as it was not clear whether it was an asteroid or a moon of Jupiter. The recognition of the latter case came by April 10.<ref name="discovery">Template:Cite journal</ref>
Pasiphae did not receive its present name until 1975;<ref>IAUC 2846: Satellites of Jupiter 7 October 1974 (naming the moon)</ref> before then, it was simply known as Template:Nowrap. It was sometimes called "Poseidon"<ref name="Gaposchkin">Template:Cite book</ref> between 1955 and 1975.
Orbit
Pasiphae orbits Jupiter on a high eccentricity and high inclination retrograde orbit. It gives its name to the Pasiphae group, irregular retrograde moons orbiting Jupiter at distances ranging between 22.8 and 24.1 million km, and with inclinations ranging between 144.5° and 158.3°.<ref name="SheppardJewittPorco2004">Sheppard, S. S.; Jewitt, D. C.; and Porco, C. C.; Jupiter's Outer Satellites and Trojans Template:Webarchive, 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, Template:ISBN, 2004, pp. 263-280</ref> The orbital elements are as of January 2000.<ref name="Jacobson 2000">Template:Cite journal</ref> They are continuously changing due to solar and planetary perturbations. The diagram illustrates its orbit in relation to other retrograde irregular satellites of Jupiter. The eccentricity of selected orbits is represented by the yellow segments (extending from the pericentre to the apocentre). The outermost regular satellite Callisto is located for reference.
Pasiphae is also known to be in a secular resonance with Jupiter (tying the longitude of its perijove with the longitude of perihelion of Jupiter).<ref name="Nesvorny2004">Template:Cite journal</ref>
Physical characteristics
With a diameter estimated at 58 km, Pasiphae is the largest retrograde and third largest irregular satellite after Himalia and Elara.
Spectroscopical measurements in infrared indicate that Pasiphae is a spectrally featureless object, consistent with the suspected asteroidal origin of the object. Pasiphae is believed to be a fragment from a captured asteroid along with other Pasiphae group satellites.<ref>Template:Cite journal</ref><ref name="SheppardJewitt2003">Sheppard, S. S.; and Jewitt, D. C.; An Abundant Population of Small Irregular Satellites Around Jupiter Template:Webarchive, Nature, Vol. 423 (May 2003), pp. 261-263</ref> The satellite appears pale red (colour indices V=17.22 B-V=0.74, R-V=0.38) though it falls into the grey color-class of C-type asteroids.<ref name="Grav2003">Grav, T.; Holman, M. J.; Gladman, B. J.; and Aksnes, K.; Photometric Survey of the Irregular Satellites, Icarus, Vol. 166 (2003), pp. 33-45</ref>