Thyone (moon)


Discovery images of Thyone by the Canada-France-Hawaii Telescope in December 2001
Discovered byScott S. Sheppard et al.
Discovery siteMauna Kea Obs.
Discovery date11 December 2001
Jupiter XXIX
Named after
Θυώνη Thyōnē
S/2001 J 2
AdjectivesThyonean /ˌθəˈnən/[3]
Orbital characteristics[5]
20940000 km
−603.58 days[4]
Satellite ofJupiter
GroupAnanke group
Physical characteristics
Mean diameter
4 km

Thyone /θˈn/, also known as Jupiter XXIX, is a retrograde irregular satellite of Jupiter. It was discovered by a team of astronomers from the University of Hawaii led by Scott S. Sheppard in 2001, and given the temporary designation S/2001 J 2.[6][1]

Thyone is about 4 kilometres in diameter, and orbits Jupiter at an average distance of 21,605,000 kilometres in 603.58 days, at an inclination of 147.28° to the ecliptic (146.93° to Jupiter's equator) with an eccentricity of 0.2526. Its average orbital speed is 2.43 km/s.

It was named in August 2003 after Thyone, better known as Semele, mother of Dionysus in Greek mythology.[7]

Thyone belongs to the Ananke group, retrograde irregular moons which orbit Jupiter between 19.3 and 22.7 million kilometres, at inclinations of roughly 150°.

Thyone imaged by the CFHT on 10 December 2001, one day before its discovery


  1. ^ a b MPEC 2002-J54: Eleven New Satellites of Jupiter 2002 May (discovery and ephemeris)
  2. ^ Noah Webster (1884) A Practical Dictionary of the English Language
  3. ^ E. R. Gregory (1989) Milton and the Muses, p. 50;
    Sidney Alexander (2016) The Complete Odes and Satires of Horace, p. 321
  4. ^ "M.P.C. 104798" (PDF). Minor Planet Circular. Minor Planet Center. 10 May 2017.
  5. ^ S.S. Sheppard (2019), Moons of Jupiter, Carnegie Science, on line
  6. ^ IAUC 7900: Satellites of Jupiter 2002 May 16 (discovery)
  7. ^ IAUC 8177: Satellites of Jupiter, Saturn, Uranus Archived 2008-07-09 at the Wayback Machine 2003 August (naming the moon)