Virginia Tech Magazine
Feature -|- Summer 2007

When President George W. Bush announced in 2004 that he wanted to restore a human presence on the moon, many Americans considered the proposal a waste of money; indeed, the Government Accountability Office now estimates that the effort will cost $230 billion. Last year, however, NASA polled more than 1,000 international scientists, engineers, and space advocates to determine what might be gained by returning to the moon. The result is a strategy that covers more than 200 mission goals, including establishing a moon base by 2025 and mining the moon for fuel.

To learn the specifics of NASA's plan to revisit the moon, Virginia Tech Magazine talked to Chris Hall, interim head of Tech's Department of Aerospace and Ocean Engineering.

One giant leap for mankind

Far more than simply retracing past steps, returning to the moon is actually the first phase for deep space exploration. "We need to learn to live and work on other planets, and the moon provides a convenient forward base for developing the necessary technologies and procedures," Hall says. Complications of living in space include contending not only with bone and muscle loss from reduced or zero gravity but also with the deadly radiation particles prevalent outside Earth's orbit. In addition, concerns exist about how a serious medical problem could be promptly treated, along with how people would fare living together in close quarters for an extended period of time.

Because of its proximity to earth, the moon is an ideal place to learn how to safely meet these challenges. "The moon is equivalent to a three-day drive from Earth so that, in principle, we could eventually go to the moon as easily as we'd drive to the West Coast," notes Hall. "The trip to Mars, by comparison, will take months and there will usually be a wait of several months before a return trip is possible."

Playing a large role in the return to the moon is the newly designed capsule that will carry astronauts. The Crew Exploration Vehicle (CEV) looks more like the old Apollo rocket and nothing like the space shuttle, which Hall attributes to the shuttle's need to reenter orbit and land like an airplane. While the CEV will also reenter Earth's orbit, the capsule will have a parachute for landing on solid ground or, if needed, at sea.

Chris Hall

Chris Hall, assistant department head of Aerospace and Ocean Engineering, teaches at both the undergraduate and graduate levels. His research in spacecraft control and dynamics has been supported by several organizations, including the NASA Goddard Space Flight Center, the National Science Foundation, and the Air Force Office of Scientific Research.

"The shuttle taught us a lot about reentry and the thermal systems that are required for reentry--and one of those lessons is that there is no advantage to the 'airplane' model," Hall comments. "There are also other advantages for the Apollo-style capsule, including the fact that the heat shielding is only exposed during reentry rather than during the entire mission as is the case with the shuttle."

The seven dwarfs meet the Jetsons?

Most discussion about mining the moon has centered around an isotope called helium-3, commonly found on the surface of the sun but only created on Earth as a by-product of nuclear-weapon maintenance. The moon, however, is estimated to harbor an extensive supply of helium-3, carried there by solar winds. Helium-3 is desirable because many consider it a viable alternative energy source: it doesn't produce radioactive waste, and scientists estimate that 25 tons of helium-3--or just one shuttle payload--could meet U.S. energy requirements for one year.

If helium-3 can be mined from the moon, nuclear science will have to catch up--energy can only be extracted from the isotope by nuclear fusion, which has yet to be proven to work on a large scale. Nor is the United States alone in planning to mine the moon; both Russia and China have announced plans to land on the moon and mine helium-3, raising the issue of who has the right to do so.

Hall says that this issue is addressed in the international "outer space treaty"—officially titled the "Treaty on principles governing the activities of states in the exploration and use of outer space, including the moon and other celestial bodies"--which was ratified in 1967 by more than 100 signatories, including all space-capable nations. "The treaty establishes the moon and other solar system bodies as being for the benefit of all humankind," Hall explains. "It also establishes broad principles, including that there will be freedom of access to space, that nations cannot claim space or planets, that nations have basic liability for damage caused by human-made space objects, and that space is for peaceful purposes only."

What the treaty does not address is the right of individuals or countries to conduct such activities as mining on the moon or other celestial bodies. An attempt to clarify this omission was the 1979 "moon treaty" (or the "Agreement governing the activities of states on the moon and other celestial bodies"), which does preclude mining on the moon or other bodies. Hall points out, however, that there are few signatories to this second treaty and that no space-capable nation has ratified it.

Which is just as well, he believes. "Establishing bases on the moon and creating capabilities to exploit its resources for the benefit of those bases will eventually lead to settlements on the moon." Researchers theorize that the process of mining helium-3 will produce other minerals, including nitrogen, helium, water, and hydrogen, all of which could go to supporting human life in bases and settlements.

The final frontier—finally

Overall, Hall strongly supports the new direction for NASA. "The Columbia disaster brought into question the nature of NASA's space exploration program," he says. "For a long time, I had been disappointed with the concept of sending a few highly trained astronauts 250 miles off the Earth's surface. That's about the distance from Blacksburg to Washington, D.C., which doesn't seem to constitute 'exploration.' Returning to the moon, establishing a permanent presence there, and then pushing on to visit Mars--that's exploration."

The timeframe includes starting, in 2008, the first of several robotic missions using the lunar reconnaissance
orbiter--a project that several Hokies are contributing to--and conducting manned missions to the moon by 2020. Hall, however, wishes that NASA were being a bit more aggressive.

"There are only two scheduled launches per year from 2013 to 2016. With four astronauts per launch, that's only eight astronauts per year, which is about the number of astronauts on a single shuttle launch. The fundamental reason that space launches are so expensive is that there aren't enough of them," he theorizes. "I'd like to see this schedule compressed, with more launches per year so that the program will eventually achieve some benefits from economy of scale."

In short, not only does Hall believe that returning to the moon is feasible, he also thinks that it is inevitable. "It will happen, and I believe that just as Great Britain was a leader in exploring and eventually settling the New World in the last millennium, the United States should be a leader in exploring the technology to create settlements on the moon in this one."

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