New information on the moon‘s evolution suggests that it may have turned itself inside out, according to NASA researchers. Simulations conducted by NASA show the moon’s mantle, the layer of hot rock beneath the moon’s crust, overturning. The exact cause of this is unknown, but the event is believed to have happened about 4.22 billion years ago. However, researchers do believe it was potentially caused by the same asteroid that created the South Pole-Aitken basin. The data also suggests the event happened relatively soon after the moon first formed.