Image: A Lunar Crater
Universe Today Download time: Apr 16 2011 8:25 AM ET
The crater shown above is located in the lunar highlands and is filled with and surrounded by boulders of all sizes and shapes. It is approximately 550 meters (1800 feet) wide yet is still considered a small crater, and could have been caused by either a direct impact by a meteorite or by an ejected bit of material from another impact. Scientists studying the Moon attempt to figure out how small craters like this were formed by their shapes and the material seen around them…although sometimes the same results can be the results of different events.
For example, when an object from space strikes the Moon, it is typically traveling around 20 km per second (12 miles/sec). If the impact site happens to have a very hard subsurface, it can make a crater with scattered bouldery chunks composed of the hard material around it.…
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