Saturn is a busy planet. The gas giant is known for its mysterious rings made up of comets, asteroids and broken rocky objects, and has the largest number of moons of any other planet in the Solar System, beating Jupiter by three more moons. Saturn’s many moons are believed to have formed around the same time as the Solar System, at least 4 billion years ago. However, a new model suggests that the orbiting moons may be a lot younger than previously thought, with some forming only a couple of million years ago.
A study, published recently in the Journal of Geophysical Research Planets, has major implications for our understanding of Saturn’s moon Titan and its chaotic, liquid-filled terrain. Samuel Bell, a research scientist at the Planetary Science Institute, and lead author of the new study, looked at the rate of impact on the different moons that orbit Saturn in order to develop a new chronology for the natural satellites. When looking at the impact craters on Saturn’s moons to help estimate their age, previous models had assumed that the impacts were a result of comets orbiting around the Sun. But there is an increased amount of evidence that the craters were formed from objects orbiting Saturn itself, smaller moonlets that are too small to detect with current telescopes. The new chronology for Saturn’s moons suggests that Titan is a much younger moon than previously believed, shaving off a few million years of its life. “The surface of Titan is younger than its neighbouring moons, it could in fact be way younger,” Bell says. “It may be around 15 million years, which is a very young, active, kind of environment.”