MOONS OF SATURN MAY BE YOUNGER THAN THE DINOSAURS

New research suggests that some of Saturn's icy moons, as well as its famous rings, might be modern adornments. Their dramatic birth may have taken place a mere hundred million years ago, more recent than the reign of many dinosaurs.

By comparing present orbital tilts and those predicted by computer simulations, the researchers have learned how much the orbits of Saturn's moons have grown. It turns out that for some of the most important satellites, Tethys, Dione and Rhea, the orbits are less dramatically altered than previously thought. The relatively small orbital tilts indicate that they haven't crossed many orbital resonances, meaning that they must have formed not far from where they are now.

But how long ago was their birth date? The team of researchers used results from NASA's Cassini mission to help answer this question. The Cassini spacecraft has observed ice geysers on Saturn's moon Enceladus. Assuming that the energy powering these geysers comes directly from tidal interactions, and that Enceladus' level of geothermal activity is more or less constant, the tides within Saturn are quite strong. According to the team's analysis, these would move the satellite by the small amount indicated by the simulations in only about 100 million years. This would date the formation of the major moons of Saturn, with the exception of more distant Titan and lapetus, to the relatively recent Cretaceous Period, the era of the dinosaurs.

Thanks to: sciencedaily.com