A tiny moon, some eight kilometres across, that forms part of a swarm of irregular objects in distant orbits around Saturn. This group of moons is collectively known as the Norse group, and Skathi gives its name to a subgroup (the Skathi subgroup) within this extensive collection of satellites. With an semi-major axis of more than fifteen million km, Skathi's orbit is distant from Saturn, but in fact it lies close to the inner edge of its group, which extends out beyond twenty-six million kilometres. Of all the Norse satellites (with the exception of a small number of tiny moonlets) only Phoebe, the first of them to be discovered, orbits more closely around the ringed planet.
Like the other Norse moons, Skathi follows a retrograde orbit (that is, it orbits in the opposite direction to Saturn's own rotation), and its orbital path is angled far from Saturn's equator. These factors imply that it did not form within the Saturnian system, but rather represents a captured object, or perhaps debris from an ancient collision between two larger bodies. Skathi's physical appearance has not been established in detail, but analysis suggests that it has an uneven appearance and a surface with a hue tending toward red in colour.
As with most of the other Norse moons, Skathi takes its name from a figure in Norse mythology, a giantess or goddess of the mountains. In the original sources, this being was named Skaði, and the ð character in that name has caused some confusion. This is an 'eth' symbol, pronounched 'th', so the name would usually be transliterated into English as 'Skathi', as indeed the moon is formally known. In some cases, however (and notably in the moon's original annnouncement), the ð has been transliterated as 'd', and so the moon is occasionally referred to as 'Skadi' rather then 'Skathi'.
|
|