Chariklo is the largest confirmed member of a class of small bodies known as centaurs, which orbit the Sun between Saturn and Uranus in the outer Solar System. A stellar occultation in 2013 revealed that Chariklo has a bright ring system consisting of two narrow and dense bands, separated by a gap of 9 km.
The existence of a ring system around a minor planet was unexpected because it had been thought that rings could only be stable around much more massive bodies. The origin of the rings is still unknown, but both are likely to be remnants of a debris disk, which could have formed via an impact on Chariklo, a collision with or between one or more pre-existing moons, tidal disruption of a former retrograde moon, or from material released from the surface by cometary activity or rotational disruption. If the rings formed through an impact event with Chariklo, the object must have impacted at a low velocity to prevent ring particles from being ejected beyond Chariklo’s Hill sphere.
Image: Artist’s impression close-up of the rings around Chariklo
Credit: ESO/L. Calçada
Read & learn:http://www.eso.org/public/news/eso1410/
Reference:http://www.nature.com/nature/journal/v508/n7494/full/nature13155.html
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