Explanation:
What created this unusual partial ring around Saturn?
Discovered last year, the arc was captured in
clear detail
only two months ago by the Saturn-orbiting
Cassini spacecraft.
Since the arc occupies the same orbit as the
small moon Anthe,
a leading hypothesis holds that the arc was created by, and is replenished by,
meteor impacts on Anthe.
Similar arcs have been previously discovered, including an
arc associated with the small Saturnian moon
Methone, one
arc related to Saturn's G ring, and several arcs orbiting
Neptune.
Pictured above,
Anthe, only two kilometers across, is seen as the bright point near the top of the Anthe arc.
The Anthe arc
was imaged by the
robotic space probe
as it swooped to within 1.5 million kilometers of the small moon.
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