Orthosie (moon)

Orthosie /ɔːrˈθz/, also known as Jupiter XXXV, is a natural 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 9.[7][1]

Discovery image of Orthosie by the Canada-France-Hawaii Telescope in December 2001
Discovery [1]
Discovered byScott S. Sheppard
David C. Jewitt
Yanga R. Fernandez
Discovery siteMauna Kea Observatory
Discovery date11 December 2001
Jupiter XXXV
Named after
Ορθωσία Orthōsia
S/2001 J 9
AdjectivesOrthosian[2] /ɔːrˈθʒiən/[3]
Orbital characteristics[4]
Epoch 17 December 2020 (JD 2459200.5)
Observation arc16.29 yr (5,949 days)
0.1415163 AU (21,170,540 km)
–629.29 d
0° 34m 19.449s / day
Inclination148.48740° (to ecliptic)
Satellite ofJupiter
GroupAnanke group
Physical characteristics[6]
Mean diameter
2 km
Albedo0.04 (assumed)

Orthosie is about 2 kilometres in diameter, and orbits Jupiter at an average distance of 21,075,662 km in 625.07 days, at an inclination of 146.46° to the ecliptic (143° to Jupiter's equator), in a retrograde direction and with an eccentricity of 0.3376.[8]

It was named in August 2003 after Orthosie, the Greek goddess of prosperity and one of the Horae.[9] The Horae (Hours) were daughters of Zeus and Themis.

Orthosie belongs to the Ananke group.


  1. ^ a b Brian G. Marsden (15 May 2003). "MPEC 2002-J54: Eleven New Satellites of Jupiter". International Astronomical Union Minor Planet Center.
  2. ^ William Beloe (1821) Herodotus, translated from the Greek, with notes, vol. 2, p. 451
  3. ^ per 'Orthosia' in Noah Webster (1884) A Practical Dictionary of the English Language
  4. ^ a b "M.P.C. 127087" (PDF). Minor Planet Circular. Minor Planet Center. 17 November 2020.
  5. ^ Sheppard, Scott. "Scott S. Sheppard - Jupiter Moons". Department of Terrestrial Magnetism. Carnegie Institution for Science. Retrieved 26 November 2020.
  6. ^ "Planetary Satellite Physical Parameters". Jet Propulsion Laboratory. 19 February 2015. Retrieved 26 November 2020.
  7. ^ Daniel W. E. Green (16 May 2002). "IAUC 7900: Satellites of Jupiter". International Astronomical Union.
  8. ^ "Ephemeris of Orthosie, Epoch 2017 Feb. 16.0 TT = JDT 2457800.5". MPC. Retrieved 13 August 2018.
  9. ^ Daniel W. E. Green (8 August 2003). "IAUC 8177: Satellites of Jupiter, Saturn, Uranus". International Astronomical Union.