A count of new crater formations on the Moon has turned up 33% more than predicted, researchers at Arizona State University have found.
Meteors regularly impact the Earth but they usually burn up in the atmosphere. On the Moon, which has no atmosphere, they constantly form craters and impact basins. Bombardment by small meteors could post hazards to future lunar settlements.
Emerson Speyerer and his Arizona State colleagues compared 14,000 photos taken between Oct. 25, 2012 and April 21, 2013 by the high-resolution camera on the Lunar Reconnaissance Orbiter (LRO), reports New Scientist. They found 222 new impact craters more than 10 meters wide, a third more than predicted. They also found 47,000 new splotches, Speyerer’s term for splatter-like changes in reflectance on the surface caused by dust and rock thrown off by the initial meteoric impact.
The largest new crater was 43 meters in diameter.
Writes New Scientist:
All these impacts suggest the moon’s surface turns over more frequently than previously thought. The first 2 to 3 centimetres of moon dust probably churns over every 80,000 years, not every million years as we previously thought — faster by a factor of 100, Speyerer says.
The revised number of craters suggests … that the soil on the lunar surface is turning over so often that materials like water molecules could escape into space sooner than previously thought. That could have important implications for researchers trying to date rocks on the moon, or future initiatives hoping to mine resources out of the moon.