With the use of seven telescopes spread across South America, observers have confirmed the unlikely discovery of a double ring surrounding the minor planet Chariklo, which holds orbit between Saturn and Uranus. Previously rings have only been found around giant planets, the most dramatic of which, Saturn, shines easily visible to the naked eye in the night sky.
The discovery was verified by observers from around the world as Chariklo passed in front of the distant star UCAC4 248-108672. Using a wide array of telescopes including the Transiting Planets and PlanetesImals Small Telescope (TRAPPIST) operated by the ESO out of the La Silla Observatory, Chile, scientists were able to observe dips in light directly before and after the main body of the minor planet passed in front of the star.
These small dips in light levels detected by the observers, are synonymous with the presence of rings orbiting a planetary body. Felipe Braga-Ribas of the Observatório Nacional/MCTI, Rio de Janeiro, Brazil, stated regarding the discovery that "We weren’t looking for a ring and didn’t think small bodies like Chariklo had them at all”.
Chariklo's rings have been nicknamed Oiapoque and Chuí after two rivers in the northern and southern extremes of Brazil (Image: ESO/L. Calçada/M. Kornmesser/Nick Risinger)
To the surprise of those observing the transition, the readings taken from the dips in light indicated that there were in fact not just one, but two rings orbiting the planet. Having analyzed the data, the team found that the system was comprised of two clearly defined rings, one measuring seven and the smaller three kilometers in width, orbiting the 250-kilometre (155-mile) -wide celestial body.
The observers believe that the existence of the rings may be the result of an impact with an asteroid, which created a field of debris. Over time the debris was manipulated by Chariklo's meager gravity to form its rings. Astronomers believe that the split composition of the rings is due to the existence of a smaller body orbiting the minor planet and distorting the debris into two distinct rings. Felipe Braga-Ribas commented on the phenomenon, stating "So, as well as the rings, it’s likely that Chariklo has at least one small moon still waiting to be discovered."
The video below displays how scientists at the ESO discovered the rings around Chariklo.