June 25, 2009
The new Augustine Commission met for the first time last week (June 17). The one-day agenda was filled with presentations on rocket-building, including reviews of NASA’s current efforts along those lines, followed by briefings on a number of possible alternatives. Suddenly, the space blogosphere was filled with speculation on the possible demise of the new Ares I launch vehicle and its replacement by either a commercial or some alternative Shuttle-derived rocket.
An early focus on rockets is perhaps inevitable, given the cost, schedule and technical issues that the Ares program has experienced. But in fact, all this rocket talk is quite beside the point. The real issue is, as it has always been, “What is the mission?” Why are we going to the Moon? Why should we send people into space? Can’t robotic missions explore the universe more cheaply and easily?
Such questions about the space program are answered repeatedly, but the discussion never advances. Recognizing that I am rushing in where space angels fear to tread, let me give it yet another go.
There are many motivations for a national space program. Scientific knowledge is an important objective, but it is not the only one and perhaps not even the most important one. The Vision for Space Exploration is being undertaken “to advance U.S. scientific, economic and security interests.” The Vision, proposed by the President and endorsed by two Congresses, was carefully crafted to give logical, long-term purpose and direction for expanded possibilities and opportunities in space. In a speech on the Vision given a couple of years after its announcement, Presidential Science Advisor John Marburger said, “Questions about the vision boil down to whether we want to incorporate the Solar System in our economic sphere, or not.”
Here is the problem. Leaving Earth means escaping from a very deep gravity well. It is very costly to lift mass out of this well; current estimates vary widely, but $20,000 per pound to low-Earth orbit is a commonly cited cost for delivery by the Shuttle. As long as we must lift everything we need in space from the surface of the Earth, we are mass- and power-limited. Thus, we are also capability-limited. And under the existing rules of spaceflight, we always will be.
So, let’s change the rules. Rather than lifting all the water, air and propellant we need up from Earth, let’s find and make those commodities in space. Once we do that, our capabilities multiply many fold. We will be able to go anywhere we want, for as long as we want, to do any job or task we can imagine.
Why the Moon? Because the Moon is the closest, most easily accessible place beyond low Earth orbit that has the resources we need. Water is the currency of spacefaring – we need it for life support, energy storage and rocket propellant. The Moon has abundant supplies of both hydrogen and oxygen; no matter what form those two elements may take, we can extract and make these needed commodities from lunar materials.
Making propellant from lunar material allows us to access not only the Moon’s surface, but any other point in cislunar space (the volume of space between Earth and Moon) on a routine basis. This zone is where all our commercial and national strategic assets reside. Rather than building custom spacecraft, launching them on an expendable rockets, using them for a few years and then abandoning them in place, we would be able to create maintainable and extensible space systems. Spacecraft can be refueled in orbit instead of launched whole cloth from Earth. The VSE asks NASA to find and use what’s out there to create a wholly new, sustainable spacefaring capability.
This is our “mission” on the Moon: learn the skills and develop the technologies needed to live and work productively on another world. Creating a space transportation infrastructure is akin to building the first transcontinental railroad; it will open up the frontier of cislunar space. And a system that can access cislunar space will take us to the planets.
NASA’s task is to probe beyond low Earth orbit—opening the space frontier for sustained exploration. The agency’s job is not to industrialize the Moon, but to answer the question, “Can the Moon be industrialized?” This new direction is far removed from the geopolitically driven Apollo template of “flags and footprints.” The multinational fleet of probes scouting the Moon is testament to mankind’s boundless curiosity and a timely reminder that those who explore, excel.
A mission statement must be clear and simple. When the mission is understood, debate about rockets and architectures take place in an information-rich environment. The launchers used and the way mission elements are put together is optimized based on the requirements of the mission. Developing those requirements cannot begin until you know the mission.
One hundred and forty years ago, the mission was understood — to span the continent with a transportation system, opening up the frontier to development. That mission created a modern industrial nation. We seek to do the same with cislunar space. And then, the planets.
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