Beneath the Moon's Two Faces
Earth is the reason the moon has two distinct sides.
Astronomers have finally figured out why the moon is so two-faced, and it turns out the answer was with us all along: It’s Earth’s fault.
The moon’s two faces look nothing alike. The far side has significantly fewer of the familiar dark patches, formed by ancient lava flows. That’s because the lunar crust is thicker there, making it harder for asteroid impacts to break through and release magma. But why was the crust thicker to begin with?
A team of Pennsylvania State U...