A new model created by MIT researchers showed that Saturn's polar cyclones are fueled by multiple small thunderstorms.
Scientists have long wondered how Saturn got its massive cyclones, each as wide as the Earth and spinning up to 300 mph, which lasts for years, despite the absence of water. The MIT researchers developed a model of Saturn's atmosphere in an attempt to solve this mystery.
The simulation showed that as multiple small thunderstorms form within the planet's atmosphere, they tend to pull each other towards the pole until they merge into a massive cyclone. The researchers concluded that the size of the thunderstorm depends on the size of the planet, as well as the energy that the cyclone will have.
In the paper published in the June 15 issue of Nature Geoscience, the researchers predicted that Neptune can also have similar cyclones while Jupiter cannot. The team continued their research to determine why Jupiter didn't form cyclones during their simulation, although their assumption suggested that it has something to do with its overall size.
"Before it was observed, we never considered the possibility of a cyclone on a pole," Morgan O'Neill, the paper's lead author and a former PhD student in MIT's Department of Earth, Atmospheric and Planetary Sciences (EAPS), said in the university news release.
"Only recently did Cassini give us this huge wealth of observations that made it possible, and only recently have we had to think about why [polar cyclones] occur."
NASA's Cassini spacecraft captured images of Saturn's polar hotspots in 2008.
The researchers also explained how Saturn got its cyclones even if it doesn't have water. They called the phenomenon "beta drift," wherein the rotation of the planet causes its small thunderstorms to drift towards the poles.
"The whole atmosphere is kind of being dragged by the planet as the planet rotates, so all this air has some ambient angular momentum," O'Neill explained. "If you converge a bunch of that air at the base of a thunderstorm, you're going to get a small cyclone."
The new model can also be used to gauge atmospheric conditions on planets outside the Solar system.
