Can you believe there are at least 400 million metric tons of water on the Moon's north pole, and the government has cancelled the return to the Moon program? The future will consider this the most shortsighted scientific policy decision of the last 50 years.
There is blather about continuing exploration long term to LaGrange points and asteroids, and maybe even Mars, but it is not sincere. Doing those as one-shot trips is just showing off at best, it is far too expensive a way to travel on a repeat basis around the inner Solar System.
With water on the Moon, we can go there and live. We can build a permanent base, we can afford to go to Mars and the outer planets - not once to show off or fulfill a childhood dream, but to explore, and develop. People who want to skip the Moon and go directly to Mars will put back the exploration of space by generations. It is far too long a trip from Earth orbit to Mars and back, using the kind of coasting space vehicles on slow looping orbits that would take years to get to Mars and back. What we need is a large space base, with its own resources that do not have to all be launched into orbit from the Earth’s surface. Fortunately, we now know there is one awaiting our development.
The Moon is the best space station possible - because it is airless, has water, and has gravity.
Because the Moon is airless, we can launch rockets from the surface without wasting most of the energy fighting air resistance. This means we can launch – and land – greater payloads with far less rocket fuel – or other energy sources.
People have mentioned the water on the Moon as a source of hydrogen and oxygen for rocket fuel, but it has a more important use. We can use it to grow food for the people who will live there. Obviously we can also recycle the water supply and use it for drinking and bathing. Can we use it for rocket fuel? Some of it, yes. But there may be a way to avoid wasting it on this.
The last, and perhaps best, thing about the Moon is it has a little bit of gravity. One sixth the gravity of the Earth, but enough to make a stable place to live and work. People are engineered for gravity, we don’t work well in weightlessness.
The Moon can be the key to affordable exploration of our Solar System – and eventually beyond to other stars.
Imagine a different way of getting to Mars. I call it the rock rocket. Instead of burning chemicals to make thrust to propel the rocket – the equal and opposite reaction of Newton’s law – we throw rocks out the back end.
Well, actually we make an ion engine – like they are already using in interplanetary probes – but we modify it to use Moon dust. Dust for thrust! You don’t need to burn anything,, you just need cheap reaction mass and an engine to give the mass momentum. Build a big rocket, fill it full of Moon dust, and head for Mars – or wherever. The energy source for acceleration might be solar, or even better, a small nuclear plant.
This kind of engine is not forceful enough to get you off the Moon’s surface, but you don’t really need a rocket to get off the Moon. A slingshot will do. Because there is no air resistance, and the gravity is light, you can build a big slingshot – like a rock on the end of a string several miles long – spin it around with mechanical energy like a giant amusement park ride, aim it where you want and let go. Once the rock rocket is on its way, you fire up the dust thruster to continue to accelerate – or decelerate at the other end. You could even send along tankers in the wake of the original rock rocket to provide it with more fuel for further acceleration, course changes, or return trips.
Most of what I am talking about here is simple – or sometimes complex – engineering. Nothing relies on new or unknown principles to succeed. For less than the cost of one or two Mars shots we could go to the Moon permanently and explore to our hearts desires. Chances are good we will find ways to make money out there and make the project profitable. If that happens, there will be hundreds – then thousands – then millions of people living off Earth.
But we have to decide to go. We have to focus on the next step in space exploration, rather than dreaming of living on Mars tomorrow.
Water on the Moon makes it all possible.