Using the moon as a base for continuing on to Mars, from a physics/energy/cost standpoint, isn't a great idea. Practice, science, testing, sure, it's great to go there. But a pit stop there on the way to Mars, not so much.
Because leaving the surface of the moon, once there, takes more energy. You've already gotten your ship at escape velocity from earth, so now you're going to expend energy slowing it down to land on the moon, then expend more energy getting escape velocity from the moon and getting back up to a reasonable speed to get to Mars in any decent length of time. That extra energy being spent to decelerate to the moon and accelerate away from it again is energy you don't need to use, when that energy is just more mass that you're going to have to lift off of the earth in the first place. You don't need to do it, there's really not a good reason to stop on the moon on the way to Mars. They're both worthy destinations in their own rights, but stopping on the way out to Mars is a waste of time and money. When we're talking many thousands of dollars per pound for everything we put on the ship going to Mars, all that fuel that isn't needed really adds up. You could replace it with more oxygen, food, and water, and spend more time on Mars rather than wasting space on the ship on the fuel you'll need to stop on the moon.
As far as the H[sub]2[/sub] tank, it probably won't explode even if the flame ran back into the hose, it may very well just extinguish itself. But a tank like that falling over and knocking the regulator off can suddenly become a missile, and a flammable missile at that. It may be that nothing bad would happen, but certainly nothing good could happen.
It was a space race and once we won there was no reason for any of the other countries to try anymore. They say it's not practical and they want to wait till the technology gets better so we can get to mars/the moon for cheaper, But there is one and only one thing that will make us go back once more and its right HERE---> http://www.youtube.com/watch?v=H9NO84uvrg8
