Saturn's iconic rings seem to have formed
early in the planet's history.
By Alexandra Witze and Nature magazine
Saturn’s spectacular ring system may date back some 4.4 billion years to the time when the planet itself formed, new findings suggest. The work could help to resolve a long-running debate about whether the rings are ancient or formed much more recently, on the order of hundreds of millions of years ago.
For the first time, NASA's Cassini spacecraft has measured the rate at which dust from outside the Saturn system is falling on the rings and polluting them. That rate turns out to be about 40 times lower than previously thought, which eliminates a major argument against the ‘old rings’ theory: that if the rings had been around for billions of years, they should have gotten coated with a dark spray of other particles and look a lot dirtier than they do.
"The rings can be three to ten times older than we used to think," says Larry Esposito, a planetary scientist at the University of Colorado Boulder.
More - :Link >>> http://www.scientificamerican.com/article/dust-reveals-ancient-origin-for-saturn-s-rings/?&WT.mc_id=SA_DD_20140821
Sources: Nature Magazine, Scientific American Magazine.
Biography of Allegheny Observatory Director James E. Keeler, who discovered the true composition of Saturn's Rings in 1895:
Link >>> http://johnbrashear.tripod.com/bio/KeelerJ.htm
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