Sinope  is a retrograde irregular satellite of Jupiter discovered by Seth Barnes Nicholson at Lick Observatory in 1914,  and is named after Sinope of Greek mythology.
Sinope did not receive its present name until 1975; (in which he declines to name the recently discovered satellites (pp. 93–94))IAUC 2846: Satellites of Jupiter 1974  October (naming the moon) before then, it was simply known as .
It was sometimes called "Hades" between 1955 and 1975.
Orbit
thumb|left|300px|Pasiphae group.
Sinope orbits Jupiter on a high-eccentricity and high-inclination retrograde orbit.
Its orbit is continuously changing due to solar and planetary perturbations.
Sinope is believed to belong to the Pasiphae group of retrograde irregular moons.Sheppard, S. S.; and Jewitt, D. C.; An Abundant Population of Small Irregular Satellites Around Jupiter, Nature, Vol. 423 (May 2003), pp.
261-263 However, given its mean inclination and different colour, Sinope could be also an independent object, captured independently, unrelated to the collision and break-up at the origin of the group.Grav, T.; Holman, M. J.; Gladman, B. J.; and Aksnes, K.; Photometric Survey of the Irregular Satellites, Icarus, Vol. 166 (2003), pp.
33-45 The diagram illustrates Sinope's orbital elements in relation to other satellites of the group.
Sinope is also known to be in a secular resonance with Jupiter, similar to Pasiphae.
However, Sinope can drop out of this resonance and has periods of both resonant and non-resonant behaviour in time scales of 107 years.
Physical characteristics
From measurements of its thermal emission, Sinope has an estimated diameter of .
Sinope is red (colour indices B−V=0.84, R−V=0.46), unlike Pasiphae, which is grey.
Sinope's infrared spectrum is similar to those of D-type asteroids but different from that of Pasiphae.
These dissimilarities of the physical parameters suggest a different origin from the core members of the group.
See also
Sinope in fiction
References
External links
Sinope Profile by NASA's Solar System Exploration
David Jewitt pages
Jupiter's Known Satellites (by Scott S. Sheppard)
Ephemeris IAU-MPC NSES
