Alternative names S/2000 S 3
Saturn XXIX Eccentricity 0.2961 Rotation period 10 h 09 m Discovered 23 September 2000 Orbits Saturn | Semi-major axis 17.531 Gm Dimensions 40 km Orbital period 896 days Inclination 46° | |
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Discovered by Brett J. Gladman et al. Discoverers John J. Kavelaars, Brett J. Gladman Similar Brett J Gladman discoveries, Saturn moons, Other celestial objects | ||
Siarnaq model p megman zx advent edit release
Siarnaq (/ˈsiːɑːrnɑːk/ SEE-ar-nahk), or Saturn XXIX, is a prograde irregular satellite of Saturn. It was discovered by Brett J. Gladman, et al. in 2000, and given the temporary designation S/2000 S 3. Named after the giant Siarnaq of Inuit mythology, it is the largest member of the Inuit group of irregular satellites.
Siarnaq is thought to be about 40 kilometers in diameter. It orbits Saturn at an average distance of 17.5 Gm in 895 days. The rotation period was measured by the Cassini spacecraft to approximately 10 hours and 9 minutes; this is the shortest rotation period of all prograde irregular moons of Saturn.
It is light red in color, and the Siarnaupian (Siarnaqan) spectrum in the infrared is very similar to the Inuit-group satellites Paaliaq and Kiviuq, supporting the thesis of a possible common origin in the break-up of a larger body.
Siarnaq has been found to be in a secular resonance with Saturn, involving the precession of its periapsis and that of the planet.1 The studies of these resonances are key to understand the capture mechanism for the irregular satellites and, assuming a common origin of a given dynamical group in the break-up of a single body, to explain today’s dispersion of the orbital elements.
1The ecliptic longitudes of the periapsis of the satellite and the planet are locked.