Stepping through the Cinder Lake Crater Field about 12 miles outside Flagstaff, Ariz., And you might encounter a white crystal-filled rock that has absolutely no business being there.
The chunks of anorthosite were not deposited there by nature – they were trucked in from the mountains around Pasadena, Calif. And the craters were carved not by meteors, but by fertilizer and dynamite.
The first one landed on the moon, NASA dispatched the Apollo astronauts to this volcanic field to search for and other faux moon rocks.
The scavenger hunt had great purpose: Anorthosite would likely be among the oldest lunar fragments, geologists believed, and they wanted to make sure the moonwalkers were able to identify the valuable specimen to bring home.
"We drilled that into the Apollo 1
The early Apollo missions were focused on beating the Soviets to the moon to prove America's technological superiority during a fraught period in the Cold War, and the astronauts who flew them were mostly pilots with little interest in rocks.
But by the time Apollo 11 blasted off, many astronauts had come to develop an appreciation for lunar geology – and the new light would be on our own planet. "Geology opened my eyes to the immensity of time," Edwin "Buzz" Aldrin wrote in his 1973 book, "Return to Earth."
This 1968 photo shows craters being created in a volcanic cinder field east of Flagstaff to mimic a particular patch of the moon's surface.
(US Geological Survey Astrogeology Science Center via Associated Press)
Northern Arizona made the crash course in field geology thanks in part to Meteor Crater, a near mile-wide wound in the desert less than 40 miles east of Flagstaff.
The crater caught the eye of USGS geologist Eugene Shoemaker, who has come to the moon but was disqualified by Addison's disease, adrenal gland disorder.
Shoemaker took the astronauts out in January 1963. Over the two-day trip, they visited Meteor Lowell Observatory.
"They were able to See and be able to learn a lot about geology. "
" Someone's talking about what's going on. " the moon to beat the Russians. What did science do to accomplish that? " Schindler said. "So the geologists who were going to train them were like, 'If we're going to inspire them to really do science, we need to take them to one of the most inspiring places in the world.' "
So they visited another northern Arizona landmark: the Grand Canyon.
Scientists led the astronauts down the Kaibab Trail, stopping along the way. They spent the night on the canyon floor and climbed up Bright Angel Trail the next day.
By the time they were done, they could have learned a story that was billions of years in the making. Both Aldrin and his Apollo 11 crewmate Neil Armstrong spoke highly of the experience.
"I found myself standing at the bottom of the Grand Canyon paying attention to the instructor's talk about things that [took] place eons before man existed on this earth, "Aldrin wrote.
Meanwhile, the geologists were doing a little learning of their own. The moon has only one-sixth gravity of Earth, so swinging a geology hammer would feel very different. And in bulky space suits with unwieldy gloves, even at work as simple as picking up rocks could become a chore.
The geologists conducted about 200 astronaut training trips between 1963 and 1972. "That's how busy we were," Schaber said. It was unbelievable. "
This 1968 photo provided by the U.S. Geological Survey Astrogeology Science Center shows man-made craters in a volcanic cinder field east of Flagstaff, Ariz. Astronauts who used the site for training.
(U. S. Geological Survey Astrogeology Science Center via AP)
On these trips, astronauts practiced using their geological hammers, hand lenses and maps to identify Telltale crystals in rocks. Laszlo Kestay, a research geologist at the USGS Astrogeology Science Center.
Some of those lessons have sunk in. Once Armstrong and Aldrin exited the Eagle, they were observing the moon like bona fide scientists, Schaber said.
"They talked about the soil, how the footprints were going, what the soil looked like, what the rocks looked like, "Schaber said. Those terms came from us, from their training. "
Harrison" Jack "Schmitt, at Apollo 17 astronaut and actual Geologist said some of his NASA colleagues were "doing their wholeheartedly in the whole thing," according to an agency report.
Kestay called "a healthy level of competitiveness." The astronauts had a "low-level rivalry about who's coming back", he said.
Some astronauts chose to do extra science training in their free time. Apollo 13 astronauts Jim Lovell and Fred Haise take a field trip with him to the Orocopia Mountains in Southern California.
"For about a week, the astronauts worked from dawn until dusk, carrying all their water and forgoing showers."
"I did two important things: I created some exercises for them, and I cooked, "Silver recounted in an oral history.
The astronauts' evolving interest in the fieldwork is mirrored in the growing realization within NASA
Even on Apollo 11, where there is something about the astronauts from their primary goal of landing on the moon and returning safely, Kestay said.  "You go back and watch the tapes," he said.
"That's the real benefit of taking the astronauts to see the most spectacular geology," he added.
That interest continues today, said geologist Lauren Edgar of the USGS Astrogeology Science Center, who is coaching astronauts who may fly to the moon with NASA's Artemis program, and perhaps on Mars.
"It's really exciting that this is currently being done in the Apollo era," Edgar said. "That's really inspiring."
This time around, you may as well as handheld X-ray fluorescence spectrometers (to analyze the elemental composition of rocks) and flying drones (to help scout the terrain ahead of them). 
© 1965 Los Angeles Times
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