Saturn's iconic rings heating its upper atmosphere, study reveals

The rings of Saturn are among the most beautiful and spectacular sights in our Solar System. However, the iconic rings are not as placid as they look - the icy ring particles are heating the planet's atmosphere - reveals a new study that pulled together archival ultraviolet-light (UV) data from four space missions that studied the gas giant.

This unexpected interaction between Saturn and its rings could provide a tool for predicting if planets around other stars have ring systems as well, the researchers say.

The study included observations from the ESA/NASA Hubble Space Telescope, the NASA/ESA/ASI Cassini probe, the twin Voyager probes and the retired International Ultraviolet Explorer mission.

The evidence comes from an excess of ultraviolet radiation detected by these space missions, seen as a spectral line of hot hydrogen in Saturn's atmosphere.

"The most feasible explanation is heating caused by icy ring particles raining down onto Saturn's atmosphere," the European Space Agency (ESA) wrote in a post.

According to astronomers, one possible explanation for this rain of particles is the impact of micrometeorites, bombardment by solar wind particles, solar ultraviolet radiation, or electromagnetic forces that pick up electrically charged dust.

By bringing together decades of UV data, the astronomers also found that there is no seasonal difference in the level of UV radiation. They are now investigating the unexpected interaction between Saturn's rings and the upper atmosphere in depth.

Their findings are published in the Planetary Science Journal.