- NASA/JPL-Caltech/Space Science Institute
Recently, scientists using NASA’s Cassini spacecraft noticed a strange ding in one of Saturn’s rings.
Saturn is sometimes called the “Jewel of the Solar System.” With shimmering pinks, hues of gray, and a hint of brown, its rings resemble a fresco where nature is the painter, NASA writes.
The rings are made of trillions of particles of dust, rock, and ice orbiting around the planet at different speeds up to thousands of miles per hour. The size of these particles can range from as small as a grain of sand to larger than a skyscraper.
The rings, only about 30 to 300 feet thick, wrap around the planet for about 175,000 miles.
The dent was found in Saturn’s F ring – its outermost discrete ring. The F ring just might be the most active ring in the solar system. Scientists can see its features changing over the course of a few hours. The disruption, NASA said, was probably caused by a small object embedded in the ring.
John Weiss, a ring scientist in Washington state, told Fusion:
There’s good evidence that there’s a lot of these sized bodies in the core of the ring itself, but you can’t normally see them because they’re covered by the dust cloud around them. But they’re in there, and every so often move across the ring space and blow a bunch of those dust particles out. This one was traveling faster than [3 feet] per second.
When the small object interacted with some of the stuff in the ring’s core, it produced something that scientists sometimes refer to as a “jet.” Astronomers think that these jets form thanks to the gravitational pull of Saturn’s small, potato-shaped moon, Prometheus.
It “acts as a cosmic shepherd, sculpting the F ring as it makes its orbit around Saturn,” National Geographic writes. “But the moon’s route isn’t perfectly circular, and its uneven pull can create clumps inside the ring that then shoot out as jets.”
The collision itself actually happened pretty recently – within a day or so of when this image was taken on April 8, Weiss said. In the two months since the picture was taken, “the wound has just about stitched itself back up,” National Geographic writes.
You get to expecting in planetary science for things to have happened millions of years ago, and you don’t think to ever get to observe things actively happening. But that’s the kind of funky thing with Saturn’s rings. You can actually see evidence of things that happened yesterday, or the day before.