Saturn's Moons and Rings Younger Than the Dinosaurs?

A grand canyon called Ithaca Chasma cuts across the fact of Saturn’s moon Tethys in this image from NASA’s Cassini probe. Scientists think the canyon opened millions of years ago when Tethys was orbitally synced with sister moon Dione.

Some of the moons and icy objects orbiting Saturn may have formed less than 100 million years ago, while dinosaurs still roamed the Earth.

The idea that some of Saturn’s moons may be relatively modern stems from computer models that simulated the moons’ gravitational interactions and shifting orbital tilts over time.

SETI Institute astronomer Matija Cuk and colleagues conclude that the moons inferior to giant Titan are not primordial, and most likely formed in the last 2 percent of the planet’s 4.5 billion-year history.

Saturn hosts at least 62 moons, 53 of which are currently named. The tally doesn’t include the hundreds of small icy objects that comprise the planet’s rings.

Titan, Saturn’s largest moon (which is bigger than the planet Mercury), is the only moon in the solar system that has a thick atmosphere.

Though most of Saturn’s current moons may be relatively new, the models show the planet has always had hordes of orbital companions.

“Our best guess is that Saturn had a similar collection of moons before, but their orbits were disturbed by a special kind of orbital resonance involving Saturn’s motion around the sun. Eventually, the orbits of neighboring moons crossed and these objects collided. From this rubble, the present set of moons and rings formed,” Cuk said in a statement.

The research is published in The Astrophysical Journal.

From Discovery News