A billion gallons is one square mile, 5’ deep.
The area of the moon is ~ 12,560,000 square miles.
So 5 divided by 12,560,000 gives you some idea of how much water you are going to find in one spot.
Yes, I know it is mainly at the poles, so feel free to take off a few zeros.
Yes, I know it is mainly at the poles, so feel free to take off a few zeros.
The billion gallon estimate is for one crater. There should be more water in other polar craters.
The mini-SAR radar of Chandrayaan-1 as well as LRO has detected what appear to be relatively pure water ice sheets at least two meters thick.
http://www.nasa.gov/mission_pages/Mini-RF/multimedia/feature_ice_like_deposits.html