Saturn's rings are one of the most phenomenal things ever seen in nature, and now there is a new puzzling little mystery in them called Peggy that scientists are trying to figure out.
The discovery by the Cassini spacecraft was announced yesterday, December 10, 2013, at this year's American Geophysical Union meeting in San Francisco. Peggy, as it has been nicknamed, is a very small object right on the edge of the A ring. Nothing like it had been seen before in this region of the ring system.
“I’d not seen anything like this personally in the A ring," said Carl Murray, a member of the Cassini imaging team during the conference.
It was first seen last April 15 in images that had been taken for the purpose of looking at the moon Prometheus. Unexpectedly, Peggy as also seen, appearing as an odd kink that jutted outward from the edge of the A ring.
Just what Peggy is isn't known yet. Estimated to be about 1 kilometre (0.62 miles) in diameter, it is too small to be considered a moon or even a moonlet. An intriguing hypothesis is that it may be a new moon just in the process of forming, from an accumulation of ring material which starts to coalesce under its own weight. Other Saturnian moons are thought to have formed this way as well, similar to how the planets formed from the dust and gas clouds orbiting the young Sun.
It will require additional observations to try to narrow down the answer, but that may not be possible, as Peggy seems to have disappeared in later images. Did it break up in a collisions or could it have already become a moonlet which has moved farther away from the A ring? Hopefully Peggy may show up again to give us a clue.
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