Erriapus
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Erriapus Template:IPAc-en, 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.<ref>Template:Cite web</ref><ref>Template:Cite web</ref> It was named Erriapo in August 2003<ref>Template:Cite web</ref> 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.<ref>Template:Cite web</ref><ref>IAUC 9191: SATURN XXVIII (ERRIAPUS) January 11, 2011</ref>
Erriapus is about 10 kilometres in diameter, and orbits Saturn at an average distance of 17.5 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,<ref name="Grav2003">Template:Cite journal</ref><ref name="Gladman2001">Template:Cite journal</ref> or to be a fragment of its largest member, Albiorix.<ref name="Grav20062">Template:Cite journal</ref> It has a rotation period of Template:Val, and is thought to rotate on its side, giving it similar seasons to those of Uranus.<ref>Template:Cite journal</ref><ref>Template:Cite conference</ref> With a fairly elongated shape, it is a candidate for a contact binary or binary moon.<ref name="Denk2018">Template:Cite book</ref>