Could someone explain this to me? I understand launching a rocket from the Moon would be much easier than from Earth, but don't we need to factor in the cost of getting the fuel to the Moon in the first place? Would there be any benefit over just launching a bigger rocket from earth? In this layman's eyes, it looks like a zero-sum game.
If this is commercially exploitable, this could be cracked into hydrogen and oxygen or otherwise be used as fuel and/or reaction mass, so it would make a huge difference in the economics of going to Mars.
Another thing needed for long-range space travel is radiation shielding, and this can be as simple as a few feet of soil -- something which can certainly be harvested from the moon.