NASA believes it is witnessing the birth of a new moon near Saturn, an event that could also provide insight to the formation of the planet's existing moons.
Thanks to images from the Cassini spacecraft, NASA scientists spotted a formation of a small icy object that appears to be a moon. Saturn has dozens of moons, but Enceladus has captured the attention of astronomers lately with apparent evidence of a subsurface ocean.
NASA's Jet Propulsion Laboratory announced the sighting of the new moon in a press release Monday, but Cassini caught the icy object one year ago Tuesday. The researchers published their work in the journal Science Direct.
"We have not seen anything like this before," report lead author Carl Murray, of Queen Mary University in London, said in the release. "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."
Cassini spotted the small icy moon on the outer edge of Saturn's A ring, but it may be falling apart. When the astronomers noticed the object, they determined it was 20 percent brighter than its surroundings.
Peggy, as the new moon is unofficially known, may not truly turn into a moon, but the findings can help NASA learn about Enceladus and Titan. It is also very small, not even half a mile wide, the scientists estimate.
"The theory holds that Saturn long ago had a much more massive ring system capable of giving birth to larger moons," Murray said. "As the moons formed near the edge, they depleted the rings and evolved, so the ones that formed earliest are the largest and the farthest out."
Based on Peggy, the scientists believe Saturn's moons formed from particles taken out of the planet's rings. They also believe Peggy has drained the rings of all its moon-forming particles.
