NASA’s Cassini Captures Formation of New Icy Moon on Saturn

Recently, NASA's Cassini Spacecraft captured images of an icy object within Saturn's rings revealing the birth process of a new moon.

The space agency released images of a small icy object on the outer edges of Saturn's ring captured by the Cassini spacecraft. These images help understand the formation of planet's known moons. Captured on April 15, 2013 by Cassini's narrow angle camera, the small icy object was seen at the outer edge of Saturn's A ring, the bright and larger ring. 

The object is informally called Peggy, and appears like a tiny speck in the images.  Based on the picture, the scientists estimate the small icy object is not more than a kilometer in diameter.  The scientists also revealed that one of the disturbances is an arc that measures 1,200 km long and 10 km wide, and is nearly 20 percent brighter than its surrounding ring.  The scientists believe that the arc and protuberances are a result of gravitational effect of a surrounding object.  

"We have not seen anything like this before," Carl Murray of Queen Mary University of London, the report's lead author, said in astatement. "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."

According to NASA, Peggy may not grow any larger and currently may be disintegrating. But this process of its formation and outward movement strengthens scientists' understanding of how the ringed planets icy moons Titan and Enceladus, were formed years ago in even more massive rings. It also offers useful information on how Earth and other planets in the Sun system have formed and moved away from the Sun.

Saturn's icy moon i.e. cloud-wrapped Titan and ocean-holding Enceladus, vary in size depending on their proximity to the planet. Farther the distance, larger the moon is. Most of the moons in the ringed planet are composed of ice.  Based on this, the researchers assume that the icy moons were basically formed from particles of icy rings and they eventually drifted outwards to merge with other moons.

"Witnessing the possible birth of a tiny moon is an exciting, unexpected event," said Cassini Project Scientist Linda Spilker, of NASA's Jet Propulsion Laboratory in Pasadena, Calif.

Spilker claims that the unmanned Cassini's orbit will drift closer to the outer edge of the A ring toward the late 2016 and will offer an excellent opportunity to conduct an in-depth investigation of Peggy and even image it.

The scientists speculate the process of formation of a moon in the planet's rings ended with Peggy, as the rings are currently depleting.  And this could be the last time such a process is being observed.

"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."