Earth Notes: The Dirt on Arizona’s Lunar Regolith
It’s hundreds of thousands of miles from Arizona’s San Francisco Volcanic Field to the Moon. But strong ties bind these two places.
One is that every astronaut who landed on the Moon trained in the cinder fields near Flagstaff. NASA scientists believed the area’s volcanic topography would prepare them exploring the lunar surface. But there’s another connection too.
On the Moon, Apollo astronauts found the surface material a challenge. The pale, powdery ‘regolith’ isn’t smoothed by wind or water. The particles remain jagged, largely due to steady impacts by tiny meteorites.
Exposure to sharp-edged regolith raised coughs and irritated astronauts’ eyes. Fine powder stuck to spacesuits and caused equipment failures.
As humans prepare to return to the Moon, understanding how to live surrounded by abrasive regolith is critical. But the stuff is hard to study. Astronauts brought back less than 200 pounds of sample lunar dirt, and there’s nothing on Earth quite like it.
But there is Merriam Crater, a large cinder cone east of Flagstaff made of glassy volcanic ash. In the 1990s, this rocky material was collected for the Johnson Space Center and milled into a Moon-like texture. Distributed to labs, the Arizona cinders constituted one small step toward humanity’s next leap back to our closest celestial neighbor.
This Earth Note was written by Peter Friederici and produced by KNAU and the Sustainable Communities Program at Northern Arizona University.