Geological Chronicle
Hubble is a lunar impact crater measuring 81.84 kilometers in diameter near the Moon's east-northeastern limb, north of Mare Marginis and northeast of Cannon. Because it sits so close to the limb, it is viewed almost edge-on from Earth, and lunar libration determines how much of it can be seen. The crater Lyapunov lies about one crater diameter to its north-northeast.
Dating to the Nectarian epoch of the lunar geologic timescale, the crater has a worn and eroded rim with an irregular edge in places. The inner wall is wider along the western side where the rim bulges slightly outward, while the eastern side is the most intact portion and presents its inner wall toward Earth.
Basaltic lava resurfaced the interior floor, giving the relatively level plain a lower albedo than the surrounding terrain, though not quite as dark as the mare to the south. The crater lacks a central peak and contains only a few tiny craterlets alongside a pair near its midpoint. It is named after American astronomer Edwin P. Hubble.