Scientists said on Thursday a calculation of the mass of the rings based on gravitational measurements of the planet collected by Cassini indicated they formed between 100 million and 10 million years ago in roughly the final 2 percent of Saturn's current age. The findings challenge the notion favored by some astronomers that the rings developed soon after Saturn formed about 4.5 billion years ago along with the other planets including Earth. "I like the rings and their fascinating dynamics, whether they are young or old," said Sapienza University of Rome aerospace engineering professor Luciano Iess, lead author of the study published in the journal Science.
