Erriapus , or Saturn XXVIII (28), is a
prograde irregular satellite
In astronomy, an irregular moon, irregular satellite or irregular natural satellite is a natural satellite following a distant, inclined, and often eccentric and retrograde orbit. They have been captured by their parent planet, unlike regular sat ...
of
Saturn
Saturn is the sixth planet from the Sun and the second-largest in the Solar System, after Jupiter. It is a gas giant with an average radius of about nine and a half times that of Earth. It has only one-eighth the average density of Earth; ...
. It was discovered by
Brett Gladman
Brett James Gladman (born April 19, 1966) is a Canadian astronomer and a full professor at the University of British Columbia's Department of Physics and Astronomy in Vancouver, British Columbia. He holds the Canada Research Chair in planetary a ...
,
John J. Kavelaars and colleagues in 2000, and given the temporary designation S/2000 S 10. It was named Erriapo in August 2003 after ''Erriapus'' (also rendered ''Erriappus''), a giant in
Gaulish mythology; the name was changed from
dative
In grammar, the dative case ( abbreviated , or sometimes when it is a core argument) is a grammatical case used in some languages to indicate the recipient or beneficiary of an action, as in "Maria Jacobo potum dedit", Latin for "Maria gave Jaco ...
''Erriapo'' to
nominative
In grammar, the nominative case ( abbreviated ), subjective case, straight case or upright case is one of the grammatical cases of a noun or other part of speech, which generally marks the subject of a verb or (in Latin and formal variants of ...
''Erriapus'' per
IAU
The International Astronomical Union (IAU; french: link=yes, Union astronomique internationale, UAI) is a nongovernmental organisation with the objective of advancing astronomy in all aspects, including promoting astronomical research, outreach ...
conventions in late 2007.
IAUC 9191: ''SATURN XXVIII (ERRIAPUS)''
January 11, 2011
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
The Gallic group is a dynamical grouping of the prograde irregular satellites of Saturn following similar orbits. Their semi-major axes range between 16 and 19 Gm, their inclinations between 35° and 40°, and their eccentricities around 0.53.
...
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,[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 or to be a fragment of its largest member, Albiorix.[Grav, T.; and Bauer, J.]
''A deeper look at the colors of Saturnian irregular satellites''
/ref> With a rotation period of and an elongated shape, it is a candidate for a contact binary
In astronomy, a contact binary is a binary star system whose component stars are so close that they touch each other or have merged to share their gaseous envelopes. A binary system whose stars share an envelope may also be called an overconta ...
or binary moon.
References
*Ephemeri
from IAU-MPC NSES
External links
{{DEFAULTSORT:Erriapus (Moon)
Gallic group
Moons of Saturn
Irregular satellites
Astronomical objects discovered in 2000
Moons with a prograde orbit