Hati (moon)

Hati
Hati imaged by the Cassini spacecraft in November 2015
Discovery
Discovered byScott S. Sheppard
David C. Jewitt
Jan T. Kleyna
Brian G. Marsden
Discovery dateDecember 2004
Designations
Designation
Saturn XLIII
Named after
Hati Hróðvitnisson
S/2004 S 14
Orbital characteristics[1]
19697100 km
Eccentricity0.375
−1040.29 days
Inclination164.1°
Satellite ofSaturn
GroupNorse group
Physical characteristics[2][3]
5+50%
−30%
 km
Mass6.5×1013 kg (calculated)
Mean density
1 g/cm3[4][5]
5.45±0.04 h
Albedo0.06 (assumed)
24.4
15.3

Hati /ˈhɑːti/ or Saturn XLIII is a natural satellite of Saturn. Its discovery was announced by Scott S. Sheppard, David C. Jewitt, Jan Kleyna, and Brian G. Marsden on 4 May 2005, from observations taken between 12 December 2004 and 11 March 2005.

Hati is about 5 kilometers in diameter, and orbits Saturn at an average distance of 19,697 Mm in 1040 days, at an inclination of 164° to the ecliptic, in a retrograde direction and with an eccentricity of 0.375, somewhat similar to Mundilfari's orbit.[1] In March 2013, the synodic rotational period was measured by Cassini to about 5.45±0.04 hours. This is the fastest known rotation of all of Saturn's moons,[2] and in fact the fastest known among all moons (including asteroid moons) for which a rotation period has been reliably measured. Like Mundilfari, it is very elongated in shape.[3]

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

  1. ^ a b "Planetary Satellite Mean Elements". ssd.jpl.nasa.gov. Retrieved 2024-02-08.
  2. ^ 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.
  3. ^ a b Denk, Tilmann; Mottola, Stefano; Tosi, Frederico; Bottke, William F.; Hamilton, Douglas P. (2018). "The Irregular Satellites of Saturn" (PDF). In Schenk, Paul M.; Clark, Roger N.; Howett, Carly J. A.; Verbiscer, Anne J.; Waite, J. Hunter (eds.). Enceladus and the Icy Moons of Saturn. Space Science Series. Vol. 322. Tucson, AZ: The University of Arizona Press. pp. 409–434. Bibcode:2018eims.book..409D. doi:10.2458/azu_uapress_9780816537075-ch020. ISBN 9780816537075.
  4. ^ Denk, Tilmann; Mottola, S. (2013-10-01). "Irregular Saturnian Moon Lightcurves from Cassini-ISS Observations: Update". Aas/Division for Planetary Sciences Meeting Abstracts #45. 45: 406.08. Bibcode:2013DPS....4540608D.
  5. ^ Abstract Book Correlating to the Online Bulletin of the American Astronomical Society (PDF). 45th Annual Meeting Division for Planetary Sciences. Vol. 45. American Astronomical Society. October 2013. p. 170.