A ring that scientists had thought could not exist has been found around a planet in our Solar System.
The ring is similar to those that wrap around other nearby planets, such as Saturn. But he found himself on a much smaller world: the newly discovered dwarf planet Quaoar.
Also, the ring is much further away than scientists thought it might be. The new ring is twice as far from Quaoar as the researchers had thought physics allowed.
As such, it requires a rewrite of our understanding of planetary ring formation and the physics that governs them. That, in turn, could help us better understand the more famous rings around better-known planets, like Saturn and Jupiter.
But more work is required to better understand how the object may exist, say the scientists.
Together, the dwarf planet and its ring orbit the Sun, past Neptune, and represent only the seventh such system to be found.
The discovery was made by an international team of astronomers using HiPERCAM, an extremely sensitive high-speed camera developed by scientists at the University of Sheffield.
It is mounted on the world’s largest optical telescope, the 10.4 meter diameter Gran Telescopio Canarias on La Palma.
Because the rings are too faint to see directly in an image, the discovery was made by observing an occultation, when Quaoar blocked the light from a background star as it orbited the Sun.
Although the event lasted less than a minute, it was unexpectedly preceded and followed by two dips in light, indicative of a ring system around Quaoar.
Ring systems are relatively rare in the Solar System, and apart from those around Saturn, Jupiter, Uranus, and Neptune, only two minor planets possess rings: Chariklo and Haumea.
All previously known ring systems can survive because they orbit close to the main body.
According to astronomers, what makes the ring system around Quaoar remarkable is that it is located at a distance of more than seven planetary radii, twice what was previously thought to be the maximum limit, which is the outer limit. from where the ring systems are located. they were thought to survive.
Therefore, the discovery has forced a rethink of ring formation theories.
Professor Vik Dhillon, co-author of the study from the University of Sheffield’s department of physics and astronomy, said: “It was unexpected to discover this new ring system in our Solar System, and it was doubly unexpected to find the rings so far away.” de Quaoar, challenging our previous notions of how such rings form.
“The use of our high-speed camera, HiPERCAM, was key to this discovery, as the event lasted less than a minute and the rings are too small and faint to see in a direct image.
“Everyone learns about Saturn’s magnificent rings as a child, so we hope this new find provides more insight into how they came to be.”
The study, published in Nature, involved 59 academics from around the world and was part-funded by the Science and Technology Facilities Council, and included six UK universities: Sheffield, Edinburgh, St Andrews, Warwick, Birmingham and the University open.
Additional Press Association reports