Saturday, April 16, 2011
Say Hello to the Moon
Not much for this blog entry since I'm on vacation.
A bit over a year ago I wrote a blog entry on Obama's NASA budget. (See here.) The gist of the article was that the consequence of concentrating on earth orbit commercial rockets instead of NASA building heavy lift vehicles was human deep space exploration.
That was then.
Two weeks ago SpaceX announced a planned development based on their Falcon 9, the Falcon Heavy. The Heavy is a semi-heavy lift vehicle capable of putting 50 tons into low earth orbit. The Saturn V could put 100 tons into orbit. Presumably, we've learned enough about miniaturization that what took 100 tons to get to the moon in 1967 could be done in 50 tons in the 21st century. Heck, most of what the Saturn V was propulsion to get to the moon. If we could scale back to a smaller payload, maybe the Falcon Heavy could reach the moon on its own.
They have also been talking about even bigger rockets.
And the target price point is cheap: $1000/pound. Much cheaper than Apollo. Way cheaper than the shuttle and with much more capacity than anything that currently exists. More capacity than the shuttle since the shuttle structure itself was so heavy it limited what the vehicle was capable of lifting.
Now, that said, we need to see what dance the funding does. I still stand behind the notion that only the government is really interested in deep space missions and a trip to the moon and has the deep pockets to fund them. Of course, I've been wrong before. Happily, happily wrong.
Elon Musk has brought the moon back within reach. (BBC article here. YouTube here. Aerospace analysis here.)
I feel strongly enough about going to the moon I'll go so far as to quote myself last year:
If we intend to do deep space manned missions, we need the Moon. To get to the Mars we need a heavy lift vehicle that will get a good sized payload completely out of Earth's gravity well-- Surprise! We need it for the Moon, too. To land humans on Mars-- or any other body with significant gravitation-- we need to know how to get there safely, how to live there safely until return, and how to return. All of this could be learned on the Moon with a 2.5 second light delay and a three day rescue mission.
But forget that for the moment. I said we need the Moon base. Hell, we need Luna City: a true colony on the Moon. Luna City would be closer in time than the American colonies were to London. So we can have all of the hard vacuum and experimentation we want (which we do not have with the ISS) along with real radiation shielding and gravity that might well be enough not to steal months and years of life from the inhabitants.
Forget even that. We need the Moon because it makes real exploration and utilization of the rest of the Solar System possible-- which, I submit, is impossible when transiting directly from Earth. The moon has about 17% of the gravity of earth. Launches from there are trivial compared to here. Toxic material? Not a problem. No environmental catastrophe on the Moon.
In addition, we can finally separate the cost of take off from the payload. The idea of an electromagnetically propelled launch system has been around since the forties. (See a patent here. Additional info here.) The idea is to transfer motion energy to a payload using ground based systems. Right now, a rocket has to carry its own fuel to lift the payload. This puts the launch system in the unenviable position of carrying the weight of the fuel to lift the payload and the parasitic weight of the fuel to lift the fuel. Does this seem smart? A better solution is to accelerate the payload and then leave the means of that acceleration behind. Only the mass of the payload is launched.
Why not do it here on earth? Several reasons: 1) is that pesky gravitational field again. It's a lot easier on the Moon. 2) There's vacuum on the Moon. Consequently, there's no loss due to friction. Not only do you need less energy to launch, launching is more efficient. 3) Energy is cheap. On earth you can get about 10 watts of solar radiation per square foot. On the Moon, it's about 130 watts/square foot.
What's needed on the moon? Smelting facilities. Factories. Heavy industry. I'm not talking about some six man habitat. We don't need ISS on the moon; we need Detroit.
This is an expensive undertaking but the very first step is to put a small manned base on the Moon.