Discovery images of Erriapus taken by the CFHT in September 2000
Discovered byJohn J. Kavelaars et al.
Discovery datein 2000
Named after
S/2000 S 10
Orbital characteristics[2]
Epoch 2000 Feb. 26.00
17 343 000 km
871.2 d
(2.38 yr)
Satellite ofSaturn
GroupGallic group
Physical characteristics
Mean diameter
28.15±0.25 h[3]
Albedo0.04 (assumed)[4]
Spectral type
light red
B−V=0.83, R−V=0.49[5]

Erriapus /ɛriˈæpəs/, or Saturn XXVIII (28), is a prograde irregular satellite of Saturn. It was discovered by Brett Gladman, John J. Kavelaars and colleagues in 2000, and given the temporary designation S/2000 S 10.[6][7] It was named Erriapo in August 2003[8] after Erriapus (also rendered Erriappus), a giant in Gaulish mythology; the name was changed from dative Erriapo to nominative Erriapus per IAU conventions in late 2007.[9][10]

Erriapus is about 10 kilometres in diameter, and orbits Saturn at an average distance of 17,3 Gm in 871 days.

As a member of the Gallic group of irregular satellites, which share similar orbital characteristics and a light-red colour, Erriapus is hypothesized to have its origin in the break-up of a common progenitor of the group,[5][11] or to be a fragment of its largest member, Albiorix.[12]


  1. ^ Discovery Circumstances (JPL)
  2. ^ Mean orbital parameters from JPL
  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. ^ Scott Sheppard pages
  5. ^ a b Grav, T.; Holman, M. J.; Gladman, B. J.; Aksnes, K.; Photometric survey of the irregular satellites, Icarus, 166 (2003), pp. 33–45
  6. ^ IAUC 7539: S/2000 S 10 December 7, 2000 (discovery)
  7. ^ MPEC 2000-Y14: S/2000 S 3, S/2000 S 4, S/2000 S 5, S/2000 S 6, S/2000 S 10 December 19, 2000 (discovery and ephemeris)
  8. ^ IAUC 8177: Satellites of Jupiter, Saturn, Uranus August 8, 2003 (naming the moon)
  9. ^ "USGS: Spelling of Saturn XXVIII". Archived from the original on 2014-02-02. Retrieved 2019-08-10.
  10. ^ IAUC 9191: SATURN XXVIII (ERRIAPUS) January 11, 2011
  11. ^ Gladman, B. J.; Nicholson, P. D.; Burns, J. A.; Kavelaars, J. J.; Marsden, B. G.; Holman, M. J.; Grav, T.; Hergenrother, C. W.; Petit, J.-M.; Jacobson, R. A.; and Gray, W. J.; Discovery of 12 satellites of Saturn exhibiting orbital clustering, Nature, 412 (July 12, 2001), pp. 163–166
  12. ^ Grav, T.; and Bauer, J.; A deeper look at the colors of Saturnian irregular satellites
  • Ephemeris from IAU-MPC NSES

External links

  • David Jewitt pages