Patterns in Uranus’ icy rings hint at the presence of two tiny, previously undiscovered moons orbiting the gas giant.
Rob Chancia and Matthew Hedman from the University of Idaho, US, examined 30-year-old data collected by the Voyager 2 probe and found the amount of icy material on the edge of two of Uranus’ brightest rings varied periodically.
This pattern at Uranus was similar to moon-related structures in Saturn’s rings, called moonlet wakes.
In a paper to be published in the Astrophysical Journal (and available on Arxiv), the pair estimates the moonlets in Uranus’ rings would be four to 14 kilometres in diameter – as small as some identified moons of Saturn, but smaller than any of Uranus’ 27 known moons.
Hedman said their findings could help explain some characteristics of Uranus’ rings, which are strangely narrow compared to Saturn’s.
The moonlets, if they exist, may be acting as “shepherd” moons, helping to keep the rings from spreading out.
Confirming whether or not the moonlets actually exist using telescope or spacecraft images will be left to other researchers, Chancia and Hedman said. They will continue examining patterns and structures in Uranus’ rings, helping uncover more of the planet’s many secrets.
Originally published by Cosmos as Wavy rings point to two undiscovered moons at Uranus
Curated content from the editorial staff at Cosmos Magazine.
Read science facts, not fiction...
There’s never been a more important time to explain the facts, cherish evidence-based knowledge and to showcase the latest scientific, technological and engineering breakthroughs. Cosmos is published by The Royal Institution of Australia, a charity dedicated to connecting people with the world of science. Financial contributions, however big or small, help us provide access to trusted science information at a time when the world needs it most. Please support us by making a donation or purchasing a subscription today.