Aristarchus is a lunar impact crater that lies in the northwest part of the Moon's near side. It is considered the brightest of the large formations on the lunar surface, with an albedo nearly double that of most lunar features. The feature is bright enough to be visible to the naked eye, and displays unusually bright features when viewed through a large telescope. It is also readily identified when most of the lunar surface is illuminated by earthshine. The crater is deeper than the Grand Canyon.