Credit: Slug Signorino

We know D.C. Get our free newsletter to stay in the know.

In his book Collapse , Jared Diamond claims, “When NASA wanted to find some place on Earth resembling the surface of the Moon, so that our astronauts preparing for the first moon landing could practice in an environment similar to what they would encounter, NASA picked a formerly green area of Iceland that is now utterly barren.” This struck me as wrong. Growing up, I heard the slag fields around Sudbury, Ontario, helped get the lunar astronauts accustomed to the moon’s desolation. I’ve heard similar things about islands in the Canadian arctic and deserts in the American southwest. I can’t see NASA hauling astronauts around the world just to look at places without trees. I wonder if the real explanation is that the astronauts had to take geology lessons. True? —Cameron Barr, Edmonton

You nailed it, friend. Most astronaut field trips were about geology, not getting used to a bleak hell unfit for life.

The astronauts trained at lots of sites in the U.S. and around the world, at least a couple of which humans had turned into wildernesses. According to Diamond, “Since human settlement began, most of [Iceland’s] original trees and vegetation have been destroyed, and about half of the original soils have eroded into the ocean.” Similarly, much of the area around Sudbury, Ontario, was a moonscape in the 1960s due to nickel smelting.

In neither case, however, was environmental devastation the main draw for NASA. Instead it was geological features. Although the real purpose of the moon shots was bragging rights, the nominal goal was scientific exploration. One thing the moon had plenty of was rocks, and that meant geology training lest the astronauts wander right past the specimens they were supposedly there to study.

After a few boring lectures, the NASA science team realized geology field trips (GFTs) better suited the former test pilots’ learn-by-doing style.

GFT sites were chosen because of geologic similarities to spots the astronauts were expected to visit on the moon. Usually that meant deserts—you couldn’t see the rocks if they were covered with vegetation. However, the astronauts also visited densely wooded northern Minnesota to see outcrops of anorthosite, a rock found on the moon. Grand Canyon trips taught stratigraphy, the study of rock layers. The trainees even visited craters formed by shallow underground nuclear tests in Nevada and by conventional explosives in Alberta, since bomb craters form the same way meteorite craters do.

The astronauts visited Iceland in 1965 and 1967. Although they undoubtedly saw many formerly green spots, the centerpiece of the visits was the Askja caldera, site of multiple volcanic eruptions. It probably wasn’t verdant even in pre-Viking days.

Ontario’s Sudbury basin was a GFT destination in 1971 and ’72 because it’s a meteorite impact crater—at 62 kilometers long one of the largest on earth. There astronauts studied shatter cones (conical, striated rock chunks) and impact breccia (rock consisting of mineral fragments embedded in natural cement), both of which they subsequently recognized on the moon.

Judging from NASA photographs, the parts of the Sudbury basin the astronauts saw weren’t particularly lunar. The Askja caldera sure was, though, as were other areas they took in: central Oregon lava fields, the Big Bend region of Texas, Los Pinacates (northwest Mexico), Kapoho (Hawaii), and Sunset Crater and Cinder Lake, near Flagstaff, Ariz. Another destination was Craters of the Moon National Monument in Idaho. My assistant Bibliophage, who’s been there, reports, “I can only say if there’s a more moonlike place on earth, I don’t want to see it.”

Some training locations were chosen for topographical similarity to landing sites (e.g., a New Mexico river gorge). To prepare for emergency landings on their return, the astronauts also underwent jungle survival training in Panama and desert survival in Nevada and Washington.

On many trips, the astronauts communicated by radio with geologists, describing interesting features. Among them: discarded beer cans and cow pies. Later, the scientists would point out the geology they’d missed while entertaining themselves. Contrary to what you might imagine, these traverses were conducted without space suits—too bulky in earth gravity.

Did Apollo astronauts train in the Canadian arctic? No, but in more recent times NASA personnel have visited some moon- and Marslike locations there. Most famous is a facility run by the Mars Society at Haughton Crater on cold, forbidding Devon Island. If you’re a Martian craving familiar surroundings, you won’t find a spot on earth much homier than that. —Cecil Adams

Is there something you need to get straight? Take it up with Cecil on