Recent research conducted by NASA and its partners is uncovering the secrets behind Saturn’s iconic rings and mysterious icy moons. Using supercomputer simulations, scientists have determined that the rings formed from a massive impact between two icy moons, dating back to the time when dinosaurs roamed the Earth.

The collision between the moons resulted in a vast amount of debris, which was captured by Saturn’s gravitational pull and began to wrap around the planet, forming the rings we know today. Additionally, any debris that did not become part of the rings likely went on to form some of Saturn’s icy moons.

The study, led by Luis Teodoro and his team, utilized the Distributed Research using Advanced Computing (DiRAC) supercomputing facility at Durham University in the United Kingdom. They created simulations of the collision and ring formation in nearly 200 different scenarios, with a resolution over 100 times higher than previous studies. The scientists also used open-source simulation code, SWIFT, to accurately model the process.

Saturn’s current rings are located close to the planet within its Roche limit, which is the distance at which a second planetary body would disintegrate due to tidal forces. The simulations revealed that many collision scenarios distributed the right amount of debris within this limit, leading to the formation of the rings.

Interestingly, Saturn’s rings are primarily composed of large chunks of ice, with very little rock or other materials. The simulations showed that this lack of rock can be explained by the type of collision modeled using DiRAC, where the rock in the cores of the colliding bodies is dispersed less widely than the overlying ice.

The simulations also suggested that a cascade of collisions could have occurred from the debris, causing additional collisions with other moons around Saturn. This could have forced precursor moons out of the rings, allowing for the formation of the moons we observe today.

But how did the moons collide in the first place? Scientists propose that the Sun’s gravity, albeit small, could have destabilized the moons’ orbits over time. This resonance effect, where the gravitational pull of the Sun elongates and tilts the moons’ orbits, eventually led to their paths crossing and the collision that formed Saturn’s rings and moons.

One of Saturn’s present-day moons, Rhea, orbits just beyond the point at which it could encounter this resonance. This suggests that Rhea must have crossed the resonance recently and formed more recently as well.

While this research provides valuable insights into the formation of Saturn’s rings and moons, many questions still remain. If some of Saturn’s current icy moons formed alongside the rings and are also young, what does that mean for moons like Enceladus, which may harbor life within their sub-surface oceans? Further research and modeling are needed to answer these questions and unravel more mysteries about Saturn and our solar system.

The study, titled “A Recent Impact Origin of Saturn’s Rings and Mid-sized Moons,” was published in The Astrophysical Journal on September 26th. As scientists continue to explore Saturn and its celestial bodies, these findings contribute to a better understanding of our fascinating universe.