Skathi (moon)
| Skathi | |
|---|---|
| Provisional or systematic name | S / 2000 S 8 |
| Central body | Saturn |
| Properties of the orbit | |
| Major semi-axis | 15,539,000 km |
| Periapsis | 11,343,500 km |
| Apoapsis | 19,734,500 km |
| eccentricity | 0.270 |
| Orbit inclination | 152.70 ° |
| Orbital time | 728.2 d |
| Mean orbital velocity | 1.55 km / s |
| Physical Properties | |
| Albedo | 0.06 |
| Apparent brightness | 23.6 mag |
| Medium diameter | ≈ 8 km |
| Dimensions | ≈ 3.1 × 10 14 kg |
| Medium density | 2.3 g / cm 3 |
| Sidereal rotation | ≈ 11 h 06 min |
| Acceleration of gravity on the surface | ≈ 0.0013 m / s 2 |
| Escape speed | ≈ 3.2 m / s |
| discovery | |
| Explorer |
Brett Gladman et al. |
| Date of discovery | September 23, 2000 |
Skathi (also Saturn XXVII) is one of the smaller outer moons of the planet Saturn .
discovery
The discovery of Skathi 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. Skathi was initially given the provisional designation S / 2000 S 8.
The moon was named after Skathi , a giantess from Nordic mythology . The term Skadi 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
Skathi orbits Saturn on an eccentric orbit at an average distance of 15,641,000 km in around 728 days and 4 hours. The orbital eccentricity is 0.2690. The orbit is inclined 152.621 ° to the ecliptic and is therefore retrograde , i.e. This means that the moon runs around the planet against the direction of rotation of Saturn.
Structure and physical data
Skathi has a diameter of only 6 km. At 2.3 g / cm 3, their density 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 23.6 m , it is an extremely faint object.
Skathi could possibly be a fragment of the 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-T23: S / 2000 S 8, S / 2000 S 10 October 8, 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
- ↑ 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 |
| Paaliaq |
Semi- major axis (km) Skathi 15,541,000 |
S / 2004 S 37 |