Earth’s gravity has influenced the orientation of thousands of faults that form in the lunar surface as the Moon shrinks, according to new results from NASA’s lunar Reconnaissance Orbiter (lRO) spacecraft.
In August, 2010, researchers using images from lRO’s Narrow Angle Camera (NAC) reported the discovery of 14 cliffs known as “lobate scarps” on the Moon’s surface, in addition to about 70 previously known from the limited high-resolution Apollo Panoramic Camera photographs. Due largely to their random distribution across the surface, the science team concluded that the Moon is shrinking.
These small faults are typically less than 10 kilometres long and only tens of yards or meters high. They are most likely formed by global contraction resulting from cooling of the Moon’s still hot interior.