The distribution of surface ice on the Moon's south pole (L) and its north pole detected by NASA's M3 instrument.

The findings, published Monday in the Proceedings of the National Academy of Sciences, said definitive evidence has been found that frozen water exists in several locations on Earth's satellite. Most of the water ice discovered during the study was found in the shadows of craters near the poles, where temperatures hardly ever reach minus 157 degrees Celsius. This is because of the moon's tilt, which doesn't allow sunlight to reach those areas.