The Age of Saturn’s Rings.

The beautiful rings of the planet Saturn, once thought to have formed around the time of the dinosaurs, are now believed to have made at the same time as the solar system itself, approximately 4.5 billion years ago. Previously, based on images and data from NASA's Voyager spacecraft in the 1970s, and later from the Hubble Space Telescope, scientists were led to believe Saturn's rings were relatively youthful and likely created by a comet that shattered a large moon, 100 million years ago.

            New data returned by NASA's Cassini spacecraft have shown scientists that Saturn’s rings are as old as Saturn itself. Before the Cassini mission planetary scientists had speculated that the rings as old as the planet should be much darker due to an ongoing collection of meteor dust and dirt. The new Cassini spacecraft observations indicate the mass of ice and rock within Saturn's gigantic ring system is likely much larger than previously thought and continuously collides, providing fresh light reflecting material to the system. This helps explain why the rings’ overall appearance remains relatively bright to ground-based telescopes and spacecraft. The more mass there is in the rings, the more raw material there is for recycling. Because the pollution is being shared by a much larger volume of ring material, it becomes diluted which explains why the rings appear brighter and more pristine than scientists expected.

            "We have discovered that the rings probably were not created just yesterday in cosmic time, and in this scenario, it is not just luck that we are seeing planetary rings now," said Larry Esposito, principal investigator for Cassini's Ultraviolet Imaging Spectrograph instrument. "They probably were always around but continually changing, and they will be around for many billions of years.”

            That is good news for astronomers who enjoy the view of Saturn and it’s rings through their telescopes.