Image showing a thrust fault having pushed crustal materials (arrows) up the side of the farside impact crater named Gregory (Image: NASA/Goddard/Arizona State University/Smithsonian)
The moon is shrinking according to a team analyzing new images from NASA’s Lunar Reconnaissance Orbiter (LRO). The images reveal previously unknown cliffs, called lobate scarbs. These are thrust faults that occur primarily in the lunar highlands that indicate the moon shrank globally in the geologically recent past and might still be shrinking today. Although they were first recognized in photographs taken near the moon's equator by the panoramic cameras flown on the Apollo 15, 16 and 17 missions, the fourteen previously unknown lobate scarbs revealed by the very high resolution images taken by the LRO camera indicate that the thrust faults are globally distributed and not clustered near the moon’s equator.