Waxing gibbous Moon, computer-enhanced image. The colour saturation of this image has been enhanced to accentuate the natural variation in colour of the Moon's surface. This brings out the differences in surface composition, which reveals that the Moon's surface comprises many different minerals. For instance, deep craters excavate bright material from below the surface, and distribute it across the surface. The Moon is said to be waxing when it is increasing in apparent size. A gibbous Moon is one that is between half and totally full.