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Saturn Put A Ring On It Relatively Recently, Study Says (npr.org)
Saturn is famous for its lovely rings, but a new study suggests the planet has spent most of its 4.5 billion years without them. From a report: That's because the rings are likely only 10 million to 100 million years old, according to a newly published report in the journal Science that's based on findings from NASA's Cassini probe. Cassini spent some 13 years orbiting Saturn before plunging down and slamming into its atmosphere. During its final orbits, the spacecraft dove between the planet and its rings. That let scientists measure the gravitational effect of the rings and get a good estimate of the ring material's mass.
What they found is that it's only about 40 percent of the mass of Saturn's moon Mimas, which is way smaller than Earth's moon. This small mass suggests that the rings are relatively young. That's because the rings seem to be made of extremely pure water ice, suggesting that the bright white rings have not existed long enough to be contaminated by the bombardment of messy, dirty comets that would be expected to occur over billions of years. Some scientists thought it was possible that darker debris from comets might lie beneath the bright ice, undetectable to their instruments, but this new study shows that isn't the case.
What they found is that it's only about 40 percent of the mass of Saturn's moon Mimas, which is way smaller than Earth's moon. This small mass suggests that the rings are relatively young. That's because the rings seem to be made of extremely pure water ice, suggesting that the bright white rings have not existed long enough to be contaminated by the bombardment of messy, dirty comets that would be expected to occur over billions of years. Some scientists thought it was possible that darker debris from comets might lie beneath the bright ice, undetectable to their instruments, but this new study shows that isn't the case.
It would be very interesting if they could collect samples of this ice and compare it to Earth's.
It's been believed that water came here via comets, I wonder if those are the same comets that made up those "pure ice" rings
We all know that Saturn's rings were created about 3 million years ago, when the aliens who built the Monolith built the Star Gate.
Read the documentary book 2001: A Space Odyssey. Note that the film version does not contain this portion of history.
General Relativity: Space-time tells matter where to go; Matter tells space-time what shape to be.
Where did it come from? Was there a water containing moot that got crashed into? Or did a comet crash into an object orbiting Saturn, or did Saturn pass though a comet debris field and collect the objects?
That's the problem. Comets are slushy mud balls, not pure water. So the rings are not just some parts of a comet that got caught in orbit around Saturn, at least not directly. It's also why I'm asking the question. IF it's not possible for the rings to have come from a comet because of their composition, where did they come from?
"File to fit, pound to insert, paint to match" - Aircraft Maintenance 101
Speak for yourself. As a geologist, I'm quite used to thinking of error bars bigger than that. You're just having a calculation failure.
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"