Siarnaq
Composite of three images taken by the Cassini spacecraft in 2013, showing Siarnaq's location at ten-minute intervals | |
| Discovery | |
|---|---|
| Discovered by | Brett J. Gladman et al. |
| Discovery site | Mauna Kea Obs. |
| Discovery date | 23 September 2000 |
| Designations | |
Designation | Saturn XXIX |
| Pronunciation | /ˈsiːɑːrnɑːk/ |
Named after | Siarnaq (Inuit mythology) |
| S/2000 S 3 | |
| Adjectives | Siarnaupian, Siarnaqian |
| Orbital characteristics | |
| Epoch 17 December 2020 (JD 2459200.5) | |
| 0.1187382 AU (17,763,000 km) | |
| Eccentricity | 0.5293834 |
| +2.42 yr (+883.87 d) | |
| 35.08520° | |
| Inclination | 43.80073° (to ecliptic) |
| 40.96116° | |
| 79.59603° | |
| Satellite of | Saturn |
| Group | Inuit group (Siarnaq) |
| Physical characteristics | |
| 39.3±5.9 km | |
| 10.18785±0.00005 h | |
Pole ecliptic latitude | 98°±15° |
Pole ecliptic longitude | −23°±15° |
| Albedo | 0.050±0.017 |
Spectral type | D (reddish) B−V=0.87±0.01 V−R=0.48±0.01 V−I=1.03±0.01 |
| 20.1 (visible) | |
| 10.9±0.05 | |
Siarnaq, also designated Saturn XXIX, is the second-largest irregular moon of Saturn. It was discovered on 23 September 2000 by a team of astronomers led by Brett J. Gladman. It was named after the Inuit goddess of the sea, Siarnaq, who is more commonly known as Sedna. Siarnaq is the largest member of Saturn's Inuit group of prograde irregular moons, which orbit far from Saturn in the same direction as the planet's rotation. The moons of the Inuit group are believed to have originated as fragments from the collisional breakup of a larger progenitor moon after it was gravitationally captured into orbit around Saturn several billion years ago. Several other small Inuit group moons share similar orbits to Siarnaq, indicating that the moon had experienced another collision after forming from its progenitor.