Skoll (moon)

Skoll
Image of Skoll taken by Cassini on February 23, 2016
Discovery[1]
Discovered byS. S. Sheppard
D. C. Jewitt
J. Kleyna
Discovery date2006
Designations
Designation
Saturn XLVII
PronunciationEnglish: /skɒl/
Old Norse: [skœlː] (approximately /skɜːrl/)
Named after
Sköll
S/2006 S 8
Orbital characteristics[2]
17560000 km
Eccentricity0.418
869 days
(2.38 yr)
Inclination156°
Satellite ofSaturn
GroupNorse group
Physical characteristics[3][4]
5+50%
−30%
 km
7.26±0.09? h
Albedo0.06 (assumed)
Spectral type
r – i = 0.36 ± 0.08[5]
24.5
15.4

Skoll or Saturn XLVII (provisional designation S/2006 S 8) is a retrograde irregular satellite of Saturn. Its discovery was announced by Scott S. Sheppard, David C. Jewitt and Jan Kleyna on 26 June 2006 from observations taken between 5 January and 30 April 2006.[2][6]

Skoll is about 5 kilometres in diameter (assuming an albedo of 0.06)[3] and orbits Saturn at an average distance of 17.6 Gm (million km) in 869 days, following a highly eccentric and moderately inclined orbit.[7] A rotation period of 7.26±0.04 h was obtained by Cassini–Huygens in 2016, but this is in strong disagreement with 2013 data for unknown reasons; one possible explanation is variation in the rotation speed and axis due to Milankovitch wobble.[4]

It was named in April 2007 after Sköll, a giant wolf from Norse mythology, son of Fenrir and twin brother of Hati.[8]

  1. ^ Discovery Circumstances from JPL
  2. ^ a b "MPEC 2006-M45: Eight New Satellites of Saturn". 26 June 2006.
  3. ^ a b Denk, T.; Mottola, S. (2019). Cassini Observations of Saturn's Irregular Moons (PDF). 50th Lunar and Planetary Science Conference. Lunar and Planetary Institute.
  4. ^ a b Denk, T.; Mottola, S.; Bottke, W. F.; Hamilton, D. P. (2018). "The Irregular Satellites of Saturn". Enceladus and the Icy Moons of Saturn (PDF). Vol. 322. University of Arizona Press. pp. 409–434. Bibcode:2018eims.book..409D. doi:10.2458/azu_uapress_9780816537075-ch020. ISBN 9780816537488.
  5. ^ Peña, José; Fuentes, Cesar (17 May 2022). "Colors of Irregular Satellites of Saturn with the Dark Energy Camera". The Astronomical Journal. 163 (6): 274. arXiv:2204.08391. Bibcode:2022AJ....163..274P. doi:10.3847/1538-3881/ac6258. ISSN 1538-3881.
  6. ^ IAUC 8727: Satellites of Saturn 30 June 2006 (discovery)
  7. ^ Scott Sheppard's pages
  8. ^ "IAUC 8826: Sats OF JUPITER, SATURN; RING OF URANUS; 2006 VV_2". www.cbat.eps.harvard.edu. Retrieved 6 October 2022.