File under, And we are so amazed ….
NASA’s Cassini spacecraft has documented the formation of a small icy object within the rings of Saturn that may be a new moon, and may also provide clues to the formation of the planet’s known moons.
Images taken with Cassini’s narrow angle camera on April 15, 2013, show disturbances at the very edge of Saturn’s A ring — the outermost of the planet’s large, bright rings. One of these disturbances is an arc about 20 percent brighter than its surroundings, 750 miles (1,200 kilometers) long and 6 miles (10 kilometers) wide. Scientists also found unusual protuberances in the usually smooth profile at the ring’s edge. Scientists believe the arc and protuberances are caused by the gravitational effects of a nearby object. Details of the observations were published online today (April 14, 2014) by the journal Icarus.
Yes, you read that correctly.
There are caveats, of course. JPL notes, “The object is not expected to grow any larger, and may even be falling apart.” Additionally, Carl Murray of Queen Mary University explained, “We have not seen anything like this before. 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.”
The important word, of course, being “may”.
Meanwhile, the newly-identified object in the A ring is named Peggy, at least until astronomers know more about what they are dealing with.
“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. According to Spilker, Cassini’s orbit will move closer to the outer edge of the A ring in late 2016 and provide an opportunity to study Peggy in more detail and perhaps even image it.
There is always more to learn. For now, there is also Cassini, ever faithful, to help us along the way.
Jet Propulsion Laboratory. “NASA Cassini Images May Reveal Birth of a Saturn Moon”. April 14, 2014.
Image credit: Cassini Imaging Team.