Siarnaq is a natural satellite of Saturn in the NASA/JPL Solar System Dynamics planetary satellite tables.
- Planet: Saturn
- Satellite: Siarnaq
- Satellite code: 629
- Physical parameters: not listed in the NASA/JPL planetary satellite physical parameters table
- Ephemeris: SAT456
- Reference frame: ecliptic
- Epoch (TDB): 2000-01-01.5
- Semi-major axis a: 17881100. km
- Eccentricity e: 0.308
- Argument of periapsis ω: 68.4 deg
- Mean anomaly M: 62.7 deg
- Inclination i: 47.8 deg
- Longitude of ascending node: 64.0 deg
- Sidereal period P: 892.6799 days
- Argument of periapsis precession period: 680.6 yr
- Longitude of ascending node precession period: 598.3 yr
- Mean elements reference: 48