From Bad Astronomy:
Most craters you see are pretty simple: something impacts the ground at high speed, BOOM!, and you get a crater like a dish tossed into soft sand. But this one has two rings, one inside the other. That can happen with huge impacts producing craters hundreds of kilometers across, but this one is small, only 230 meters from side to side – an American football stadium would just fit inside this crater.
Observations at many sites in South America, including the European Southern Observatory's (ESO) La Silla Observatory, have made the surprise discovery that two dense and narrow rings surround the remote asteroid Chariklo. This is the smallest object by far found to have rings and only the fifth body in the solar system — after the much larger planets Jupiter, Saturn, Uranus, and Neptune — to have this feature. The origin of these rings remains a mystery, but they may be the result of a collision that created a disk of debris.
This beautiful and eerie photograph is evidence of what astronomers believe could be remnants of a head-on collision of 2 asteroids, resulting in an X-shaped debris pattern ahead of a long stream of dust that's usually indicative of a comet.
While moonwalker Buzz Aldrin thinks that a mission sending humans to an asteroid is a good idea, the Apollo astronaut isn't so happy with NASA's current plan to use a robot to shrink-wrap a space rock and park it near the moon.
The space agency's asteroid plan centers on launching a robotic mission that aims to capture an asteroid — or a smaller boulder from a space rock — and deliver it to an orbit around the moon where astronauts can visit and sample it sometime in the 2020s. Aldrin would rather see NASA launch astronauts on a mission to an asteroid still in deep space.
