Scientists could soon get a precise age for the giant impact basins on the moon, and a better understanding of the impact history of the young Earth, thanks to a new geological map of the moon's youngest large impact site, the Mare Orientale basin.
Mare Orientale sits on the edge of the face of the moon that we can see from Earth, on the boundary between the lunar near and far side. A mare is a low-lying expanse on the moon that is flooded with basaltic lava and appears darker than the surrounding highlands (creating the visage of the "man in the moon"). Before the telescopic era resolved the maria for what they really are, they were thought to be seas. ("Mare" is the Latin word for sea.)
