Cassini May Have Captured an Image of Saturn’s Rings Giving Birth to a New Moon: “Peggy”

The Cassini spacecraft has been bringing us great shots of Saturn for a while now, but this new image may shed some light on a pretty rare phenomenon: the formation of a moon. It appears that particles on the outer edges of Saturn’s rings are forming together and may be showing us how Saturn got so many moons.

“Witnessing the possible birth of a tiny moon is an exciting, unexpected event,” said Linda Spilker, a Cassini Project Scientist at NASA’s Jet Propulsion Laboratory.

The icy body causing the disturbance, which has been nicknamed “Peggy” according to NASA’s Jet Propulsion Laboratory, may not ever actually form into a moon, but it’s grown massive enough that it’s causing gravitational disturbances in the surrounding area of the rings. Whether or not it ever breaks away and becomes its own entity, it may give us a good idea of how Saturn’s many icy moons formed.

I guess the old, “Well, when a planet and its rings love each other very, very much…” wasn’t a satisfactory explanation of moon birth for NASA’s scientists. Instead, they believe that Saturn once had a much larger ring system, and that the icy chunks formed together and drifted outward to create its 62 known moons.

The larger moons drifted farther away from the planet, the smaller ones stayed a bit closer, and the tiny moon-babies that never formed hung around to become the ring system we know today. Peggy’s birth would be the first time we’ve ever seen this process in progress.

“We have not seen anything like this before,” said Carl Murray of Queen Mary University of London, the lead author of the intial report on the images, which was published in the journal Icarus. “We may be looking at the act of birth, where this object is just leaving the rings and heading off to be a moon in its own right.”

Now we just have to wait and see how long it takes for the baby-moon to grow into a fully formed moon and emerge from the Saturn’s rings. If moon formation takes as long as I’m guessing it does, the rings are never going to let Peggy hear the end of it.

(via Science Daily, image via NASA/JPL)

Meanwhile in related links

• Animated space photos in the movie In Saturn’s Rings will make your jaw drop
• Another of Saturn’s moons, Titan, may have rippling waves on its seas of methane
• Here’s another great view of Saturn that we got thanks to Cassini