NASA's Lunar Reconnaissance Orbit Camera has been taking pictures of the surface of the moon and has shown us that there are more graben than scientists had thought on the moon. Graben are certain features on that show the moon's crust pulling apart. Researchers believe that they form because the force of pulling the moon apart is greater than the force trying to shrink the moon in.

This contradicts previous findings as of August 2010 where it was shown that the lunar surface would contract. These contractions appeared in ridges known as lobate scarps. Because of the presence of these lobate scarps, the moon's diameter was shrinking and it was thought that it would continue to shrink, until these recent images were studied.

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