Thrymr (moon)

Thrymr
Provisional or systematic name	S / 2000 S 7
Central body	Saturn
Properties of the orbit
Major semi-axis	19,941,000 km
Periapsis	10,549,000 km
Apoapsis	29,333,000 km
eccentricity	0.471
Orbit inclination	176.0 °
Orbital time	1094 d
Mean orbital velocity	1.33 km / s
Physical Properties
Apparent brightness	23.9 likes
Medium diameter	≈ 7 km
Dimensions	≈ 2.1 × 10 14 kg
Sidereal rotation	≈ 38 h 47 min
Acceleration of gravity on the surface	≈ 0.0011 m / s 2
Escape speed	≈ 2.8 m / s
discovery
Explorer	Brett Gladman et al.
Date of discovery	December 7, 2000

Thrymr (also Saturn XXX) is one of the smaller outer moons of the planet Saturn .

discovery

The discovery of Thrymr by a team of Brett Gladman , John J. Kavelaars , Jean-Marc Petit, Hans Scholl , Matthew J. Holman , Brian G. Marsden , Philip D. Nicholson and Joseph A. Burns on September 23rd through November 27, 2000 was announced on December 7, 2000.

Thrymr was initially given the provisional designation S / 2000 S 7. The moon was named after Thrymr , a frost giant from Nordic mythology .

The term Thrym is often used for the moon, and this name was first published. However, the Working Group for Planetary System Nomenclature (WGPSN) of the International Astronomical Union (IAU) later decided to use the original Nordic spelling.

Orbit data

Thrymr orbits Saturn on an eccentric orbit at a mean distance of 20,219,000 km in 1091 days and 18 hours. The orbital eccentricity is 0.3336. The orbit is inclined 175.815 ° to the ecliptic and is therefore retrograde, i.e. That is, the moon runs around the planet in the opposite direction to the direction of rotation of Saturn.

Structure and physical data

Thrymr has a diameter of only 5.6 km. Its density of 2.3 g / m ^{3 is} relatively high compared to the other Saturnian moons. It is probably composed of water ice with a high proportion of silicate rock. It has a very dark surface with an albedo of 0.06, i.e. That is, only 6% of the incident sunlight is reflected .

With an apparent brightness of 23.9 ^m , it is an extremely faint object.

Thrymr is possibly a fragment of Saturn's moon Phoebe that was blasted off in an impact event .

Web links

• IAUC 7538: S / 2000 S 7, S / 2000 S 8, S / 2000 S 9 December 7, 2000 (discovery)
• MPEC 2000-Y15: S / 2000 S 1, S / 2000 S 2, S / 2000 S 7, S / 2000 S 8, S / 2000 S 9 December 19, 2000 (ephemeris)
• MPEC 2001-X20: S / 2000 S 7 December 6, 2001 (rediscovery)
• IAUC 8177: Satellites of Jupiter, Saturn, Uranus August 8, 2003 (numbering and naming)
• IAUC 8471: Satellites of Saturn January 21, 2005 (naming correction)

Individual evidence

1. ↑ T. Denk, S. Mottola (2019): Studies of irregular satellites: I. Lightcurves and rotation periods of 25 Saturnian moons from Cassini observations. Icarus 322 , 80-102. DOI: 10.1016 / j.icarus.2018.12.040 .

further inside	Saturn moons	further outside
Color auti	Semi- major axis  (km) Thrymr 20,474,000	S / 2007 S 3