Arizona Public Radio | Your Source for NPR News

Earth Notes: The Dirt on Arizona’s Lunar Regolith

Your browser doesn’t support HTML5 audio

Apollo 12 astronaut Alan Bean holds a special environmental sample container filled with lunar soil collected during his sojourn on the lunar surface. A Hasselblad camera is mounted on the chest of his spacesuit. Pete Conrad, who took this image, is reflected in Bean's helmet visor, Nov. 20, 1969.

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.

  • Facebook
  • Twitter
  • LinkedIn
  • Email
Peter Friederici is a writer whose articles, essays, and books focus primarily on connections between humans and their natural surroundings. His most recent book is Beyond Climate Breakdown: Envisioning New Stories of Radical Hope (MIT Press, 2022). He also teaches classes in science communication and sustainable communities at Northern Arizona University.