UH scientists envision mining town on moon

UH scientists tout possibilities of nuclear fusion

SAN FRANCISCO » In this city famous for the Gold Rush, a University of Hawaii researcher joined a former Apollo astronaut yesterday in touting the mining of a resource on the moon that holds the promise of cheap, clean abundant energy on Earth.

The resource is helium-3, a rare isotope on Earth that is plentiful on the lunar surface due to billions of years of exposure to the solar wind.

Ex-astronaut Harrison Schmitt, a former U.S. senator from New Mexico now with the University of Wisconsin at Madison, told research conventioneers that helium-3 would make an ideal fuel for nuclear fusion, the same process that powers the sun.

"Helium-3 and other lunar resources are the key ingredients to affordable access to and settlement of space," said Schmitt, the last person to set foot on the moon as an Apollo 17 geologist in 1972.

"Because of these resources, we can stand here and talk to you about the long-term feasibility of lunar settlements," Schmitt said during a three-hour symposium at the annual meeting of the American Association for the Advancement of Science.

UH-Manoa geophysicist G. Jeffrey Taylor, another featured speaker, said helium-3 would be easy for prospectors to mine from lunar surface dust.

"The resource is there and it is relatively easy to get at," he said in an interview after the panel session. "Half of it will come out just by handling the stuff and the other half will come out by heating the stuff to modest temperatures. So it is really feasible to extract that resource -- if we have the fusion gizmo here on Earth."

As distinct from nuclear fission -- the splitting of heavy atoms and the force behind atomic bombs -- fusion involves combining light atoms, usually hydrogen or helium or their cousins. The technology behind sustaining a large-scale fusion reaction may be decades away, but Schmitt said a small reaction involving deuterium and helium-3 has already been achieved at the University of Wisconsin.

"At this experimental level, it is a very real thing," he said.

Deuterium, or heavy hydrogen, has a neutron in addition to normal hydrogen's single proton and electron. Helium-3 carries one neutron instead of two.

The beauty of helium-3, Schmitt said, is that its fusion products include no radioactive waste. Unlike other types of nuclear fuel, it has no weapons applications, he added.

And helium-3 fusion rockets would be perfect for voyages to Mars and beyond, he said.

The scientists painted a colorful picture of a future lunar mining town with adventurous but disciplined quasi-permanent settlers that live off the land and combine science with commercial interests.

"Prospecting and extracting resources will create new capabilities and opportunities for the scientific exploration of the moon," said Taylor. "Science and applied science are two parts of the same coin."

Although helium-3 concentrations measure only about 20 parts per billion in the moon's topsoil layer, it is believed to be common across the lunar surface.

"That's a bit low, but we mine things now that are valuable enough at 20 parts per billion," he said.

Schmitt said helium-3 fusion offers a ray of hope for an energy-ravenous world that will reach a population of 10 billion by around 2050, particularly as fossil fuels dwindle. He advanced his arguments in a 2006 book, "Return to the Moon: Exploration, Enterprise, and Energy in the Human Settlement of Space."

Also on the panel were Paul Spudis of the Applied Physics Laboratory in Maryland; Wendell Mendell of NASA's Johnson Space Center in Houston; and Simon Worden of the NASA Ames Research Center at Moffett Field, Calif.