Even though humans have pondered the moon since the first of us looked skyward, there is still much we don't know about it.

has lent support to the hypothesis that the moon does in fact possess such a molten layer hidden deep in its interior. Just as Earth has tides that are influenced by the gravitational pull of the ...

The icy shell of Titan, Saturn's largest moon, may possibly contain a six-mile-thick layer of methane ice beneath its surface. The methane layer could make it easier to detect signs of life from ...

Two canyons that splay out from a vast asteroid crater on the moon may have been quickly formed by chains of impacts that followed the initial one ...