The Mystery Behind Moon's Strange Shapes

— -- A massive shape on the moon's surface was formed by ancient rift valleys, according to new research, revising an earlier theory that the expansive region was the result of an asteroid strike.

It was previously believed that the Ocean of Storms, a region on the moon's surface spanning 1,600 miles, was the result of an asteroid impact that left a significant basin on the lunar surface.

However, readings from NASA's Gravity Recovery and Interior Laboratory mission have revealed that beneath the surface of the shape is a rectangular region that was created by cooling lava as the moon formed, visible in NASA's color-enhanced image as the blue area in the northern hemisphere.

Over time, the lava would cool and contract, creating fractures, much like dried mud, NASA said.

It is believed the rift valleys may have at one time resembled similar zones found on Earth, Mars and Venus, proving the moon is even more dynamic than was previously believed.