Dia (moon)


Discovered byScott S. Sheppard, David C. Jewitt, Yanga R. Fernández, and Eugene A. Magnier
Discovery siteMauna Kea Obs.
Discovery date5 December 2000
11 September 2012 (rediscovery)
Jupiter LIII
Named after
Δῖα Dīa
S/2000 J 11
AdjectivesDian /ˈd.ən/
Orbital characteristics[2]
12118000 km
+287.0 days
Satellite ofJupiter
GroupHimalia group
Physical characteristics
Mean diameter
4 km

Dia /ˈd.ə/, also known as Jupiter LIII, is a prograde irregular satellite of Jupiter. Provisionally known as S/2000 J 11, it received its name on March 7, 2015.[3] It is named after Dia, daughter of Deioneus (or Eioneus), wife of Ixion. According to Homer, she was seduced by Zeus in stallion form; Pirithous was the issue.

The satellite is one of the three known small bodies in the Himalia group,[4] the other two being Ersa and Pandia.

Dia is thought to be about 4 kilometres in diameter.[5] It orbits Jupiter at an average distance of 12 million km in 274 days, at an inclination of 28° (to Jupiter's equator), and with an eccentricity of 0.21.[6]

Observational history

Dia imaged by the Canada-France-Hawaii Telescope in December 2001. In the second frame Dia is not visible due to Jupiter's glare reducing the relative brightnesses of the stars.

Dia was discovered by a team of astronomers from the University of Hawaii led by Scott S. Sheppard in 2000 with an observation arc of 26 days.[7][8]

Initial observations were not followed up, and Dia was not observed for more than a decade after 2000. This apparent disappearance led some astronomers to consider the moon lost.[9] One theory was that it had crashed into Himalia, creating a faint ring around Jupiter.[10] However, it was finally recovered in observations made in 2010 and 2011.[6]


  1. ^ Noah Webster (1884) A Practical Dictionary of the English Language
  2. ^ S.S. Sheppard (2019), Moons of Jupiter, Carnegie Science, on line
  3. ^ CBET (Central Bureau Electronic Telegram) 4075: 20150307: Satellites of Jupiter, March 7, 2015
  4. ^ Sheppard, S. S.; Jewitt, D. C.; An abundant population of small irregular satellites around Jupiter Archived August 13, 2006, at the Wayback Machine, Nature, 423 (May 2003), pp. 261–263
  5. ^ Sheppard, S. S.; Jewitt, D. C.; Porco, C.; Jupiter's outer satellites and Trojans Archived June 14, 2007, at the Wayback Machine, in Jupiter: The planet, satellites and magnetosphere, edited by Fran Bagenal, Timothy E. Dowling, William B. McKinnon, Cambridge Planetary Science, Vol. 1, Cambridge, UK: Cambridge University Press, ISBN 0-521-81808-7, 2004, pp. 263-280
  6. ^ a b Williams, Gareth V. (September 11, 2012). "MPEC 2012-R22 : S/2000 J 11". Minor Planet Center. Retrieved September 11, 2012.
  7. ^ Daniel W. E. Green (January 5, 2001). "IAUC 7555: Satellites of Jupiter". International Astronomical Union.
  8. ^ Brian G. Marsden (January 15, 2001). "MPEC 2001-A29: S/2000 J 7, S/2000 J 8, S/2000 J 9, S/2000 J 10, S/2000 J 11". International Astronomical Union Minor Planet Center.
  9. ^ "FAQ: Why don't you have Jovian satellite S/2000 J11 in your system?". JPL Solar System Dynamics. Retrieved February 13, 2011.
  10. ^ "Lunar marriage may have given Jupiter a ring", New Scientist, March 20, 2010, p. 16.(subscription required)

External links

  • Natural Satellites Ephemeris Service Minor Planet Center
  • Planetary Satellite Mean Orbital Parameters NASA JPL
  • Scott Sheppard pages
  • David Jewitt pages