NASA announced today an intrasolar oddity--a Centaur astroid called Charilko looks to be the first ever ringed asteroid system. The rings are likely made up of ice drummed up from another object impacting the asteroid, which sits between Saturn and Uranus.
At 155 miles across, or about the length of Massachusetts, Chariklo is the largest known asteroid in its neighborhood. Looking to get a better idea of its exact size and shape, astronomers trained their telescopes on the giant space rock as it passed in front on a distant star in June 2013. As Chariklo performed its eclipse, researchers noticed something odd: The star’s light flickered just a bit immediately before and after Chariklo’s pass.Pretty sweet discovery--and it doesn't sound like astronomers had expected it!
The reason for this darkening was the asteroid’s two dense rings, which had briefly blocked the starlight. The thicker inner ring is about four miles wide, while the thinner outer ring is a little less than two miles. Spectroscopic analysis of the starlight also revealed that the rings are composed partially of water ice.
Click to enlarge:
Arist conception by artist Lucie Maquet