Ymir (moon)

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Ymir
Discovery[1]
Discovered by Brett J. Gladman
Discovery site Observatoire de la Cote d'Azur
Discovery date 2000
Designations
Alternative names S/2000 S1
Semi-major axis 23,040,000 km
Eccentricity 0.3349
Orbital period 1315.14 d (3.6 yr)
Mean anomaly 244.521°
Inclination 173.125°
Longitude of ascending node 194.086°
Argument of perihelion 22.668°
Satellite of Saturn
Physical characteristics
Dimensions 18 km[3]
Mass 5.1×1015 kg[4]
Escape velocity 8.7 m/s (31 km/hr)[4]
Albedo 0.06[5]
Apparent magnitude 21.7[3]

Ymir (pronounced /ˈɪmɪr/ IM-irr) or Saturn XIX is a retrograde irregular moon of Saturn. It was discovered by Brett J. Gladman, et al. in 2000, and given the temporary designation S/2000 S 1. It was named in August 2003, from Norse mythology, where Ymir is the ancestor of all the Jotuns or frost giants.[6]

Of the moons that take more than 3 Earth years to orbit Saturn, Ymir is the largest.[3] It is 18 km in diameter and takes 3.6 Earth years to complete an orbit around Saturn.

[edit] References

  1. ^ Brian G. Marsden (2000 October 25). IAUC 7512. IAU. Retrieved on 2008-02-14.
  2. ^ Jacobson, R.A. (2007) SAT270, SAT271 (2007-Jun-28). Planetary Satellite Mean Orbital Parameters. JPL/NASA. Retrieved on 2008-02-14.
  3. ^ a b c Scott S. Sheppard. Saturn's Known Satellites. Department of Terrestrial Magnetism. Retrieved on 2008-02-14.
  4. ^ a b assume radius of 9 km; volume of a sphere * assume density of 1.7g/cm³ (though it could be a loose rubble pile) yields a mass of 5.1e15 kg and an escape velocity of 8.7 m/s (31 km/hr)
  5. ^ Nicholson, P. D. 2001
  6. ^ Daniel W. E. Green (2003 August 8). IAUC 8177: Sats OF (22); Sats OF JUPITER, SATURN, URANUS. IAU. Retrieved on 2008-02-14.

[edit] External links

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Moons of Saturn
Generally listed in increasing distance from Saturn. Temporary names in italics.
Ring shepherds
Co-orbitals
Inner large (and Trojan)
Mimas · Methone · Anthe · Pallene · Enceladus · Tethys (Telesto • Calypso) · Dione (Helene • Polydeuces)
Outer large
Inuit group
Norse group
Phoebe · Skathi · S/2007 S 2 · Skoll · S/2004 S 13 · Greip · Hyrrokkin · Mundilfari · Jarnsaxa · S/2006 S 1 · S/2004 S 17 · Narvi · Bergelmir · Aegir · Suttungr · S/2004 S 12 · Bestla · Farbauti · Hati · S/2004 S 7 · Thrymr · S/2007 S 3 · S/2006 S 3 · Surtur · Kari · Fenrir · Ymir · Loge · Fornjot
Gallic group
Rings of Saturn · Cassini-Huygens · Themis · Chiron