'Propeller' moonlets strengthen theory of Saturn's rings

0 Comments | AFP, October, 2007

PARIS (AFP) — A clutch of baby moons detected in Saturn's outermost ring has bolstered a theory that the giant planet's magnificent circles were created from icy satellites that smashed up over tens of millions of years.

Eight "moonlets" -- large boulders measuring between 60 and 140 metres (yards) across -- were spotted by the US-Italian probe Cassini as they swung through Saturn's A ring.

As they move forward, the rocks scatter aside smaller debris in front and behind, rather as a ship's bow pushes aside water and its stern leaves a wake.

The disturbance in the dense particle field of the A ring looks from a distance like tiny propeller shapes.

The astronomers, led by Miodrag Sremcevic of the Laboratory for Atmospheric and Space Physics at the...