University Times

Future residents of the moon may breathe easier thanks to work being done now by Pitt professor Bruce Hapke.

Hapke, professor emeritus of geology and planetary sciences, is part of a six-member team led by NASA chief scientist Jim Garvin seeking concentrations of oxygen-bearing minerals on the moon.

The group is analyzing ultraviolet photos of the moon taken in August by the Hubble Space Telescope in search of the oxygen-bearing mineral ilmenite.

Ilmenite, a combination of iron oxide and titanium oxide, is roughly 10 percent oxygen by weight and, when heated, gives up that oxygen. “Ilmenite is of great interest because you can extract oxygen very easily from it,” Hapke said. “This would supply oxygen for a lunar colony.”

Ilmenite also absorbs hydrogen, which hits the moon in the form of solar wind. “It would be another resource,” perhaps to make water, Hapke said.

The research is being done in support of a new NASA initiative that plans to establish a base on the moon by 2018. “The ultimate objective is to make a colony or at least a station that’s more or less self-sustaining,” Hapke said.

Hapke’s proposal to view the lunar surface under ultraviolet light built on a study of the reflectance of lunar samples in UV light done a quarter-century ago by a former student, Jeff Wagner.

“It was a region of the spectrum that had not been used in remote sensing before,” Hapke said. The earth’s atmosphere filters UV, so an escape from the atmosphere was necessary.

“We thought it would be neat to see if we could use the Hubble to see … what kind of spectral information was there,” he said.

NASA agreed, and under the full moon in mid-August, the Hubble turned its normally long-range gaze toward the Earth’s nearest cosmic neighbor.

“It was technically very difficult,” Hapke said. Finicky gyroscopes aboard the Hubble, coupled with the telescope’s traveling speed of about 5 miles per second and the moon’s nearness, made taking clear pictures a tough task. But, over the course of several days, the Hubble snapped dozens of photos of the Apollo 15 and 17 landing sites as well as the geologically diverse Aristarchus crater and Schroter’s Valley regions.

The Apollo sites were chosen because the numerous mineral samples collected by Apollo crews can provide “ground truth” for determining what minerals might be found in unexplored lunar regions such as Aristarchus, Hapke said.

The Apollo 17 site is known to be rich in ilmenite, he said. “If it were on earth, it would be a titanium mine.”

The Apollo moon rocks, coupled with UV photos, can help the scientists correlate the samples with the spectrum.

“We’re absolutely sure we can determine [ilmenite] is there; now we’re trying to quantify it,” he said.

Several years’ worth of analysis is ahead, but the team is laying the groundwork for speedier analysis of future UV photo missions.

Hapke, who has been at Pitt since 1967, looks forward to discovering what can be gleaned from the photos, marveling that the project is based on work done decades ago.

“I never dreamed it would take 25 years to apply it,” he said. “The whole thing is just exciting.”

—Kimberly K. Barlow