CORRECTION: Former NM senator became twelfth moonwalker in 1972

Dec. 11—Correction: This story has been amended to reflect the following correction. A previous version of this story incorrectly reported Harrison "Jack" Schmitt was the last American to walk the moon. Astronaut Eugene Cernan took the last steps on the surface during the Apollo 17 mission.

Just before taking off on what would be the last space mission in which men walked the moon, astronaut Harrison H. "Jack" Schmitt did something unexpected.

He grabbed a nap.

When the launch of Apollo 17 in 1972 was delayed by a minor computer glitch, Schmitt was nonplussed. He recalled it this way in a 2000 interview: "I fell asleep. Anytime you put fans humming or a little bit of vibration, things like that, I can go to sleep."

He awoke soon enough: Once Apollo 17 left its launchpad, Schmitt and the two other astronauts on the flight — spaceship pilot Eugene Cernan and command module pilot Ronald Evans — were speeding toward the moon at a speed of 25,000 miles an hour.

Their trip was largely forgotten until recently, as the 50th anniversary of America's final manned moon mission and the nation's renewed interest in the moon collided.

Fifty years ago this week, Schmitt became the twelfth man to set foot on the moon — the ultimate adventure in an era when lunar landings and exploration made hearts flutter and imaginations wander.

A half-century later, only now is the U.S. space program renewing its interest in its nearest interstellar neighbor, with the Artemis program. The throughline is Schmitt, now 87. The geologist from New Mexico is scheduled to attend a Wednesday celebration at the National Academy of Sciences that will honor the flight of Apollo 17.

There's plenty to talk about: Space experts say the Apollo 17 mission was particularly significant, and not just because it was the last. Many laud Schmitt's participation as a scientist, noting his contributions to the effort helped alter the view of exactly what was on the moon's surface.

Cernan and Schmitt, who walked the moon while Evans manned the orbiting command module, gathered rocks and specimens from a vast lava plain. They also brought back samples from a crater rim that had orange soil formed by volcanic explosions.

"That was pretty significant," Tom Watters, a senior scientist with the the Smithsonian Institution's National Air and Space Museum in Washington, D.C., said in an interview last week. The soil retrieved from the surface "indicates there was an eruption that was like a fountain-type eruption like we're seeing on Mauna Loa [in Hawaii]."

Which means as far back as billions of years ago, the moon was the site of volcanic eruptions, as NASA suspected, he said.

Watters cited Apollo 17 as the "most ambitious of the science-driven missions" NASA conducted in the 1960s and 1970s.

Christopher Orwoll, executive director of the New Mexico Museum of Space History, said Schmitt's input in both the planning and execution of Apollo 17 was critical.

During the Apollo program, Schmitt also helped train astronauts how to conduct geological expeditions for previous missions, Orwoll said.

"Getting a chance to go on this mission was not only a dream come true for him but a dream come true for the geological and scientific community to get someone on the surface of the moon with a trained eye," Orwoll said.

It paid off when Schmitt spied the orange soil around his feet — an exciting moment because "there's so little color on the moon," said Michael Neufeld, senior curator for the Space History Department at the National Air and Space Museum.

He said that discovery alone contributed to the historical significance of the Apollo 17 in that it posed the question: "How was this area formed?"

It's a question still being analyzed as NASA's Artemis 1's unmanned Orion capsule plans to splash down Sunday off the coast of Baja California. Among other goals, the Artemis 1 mission is intended to pave the way for astronauts — both men and women — to fly to the moon again, perhaps as soon as 2024.

Schmitt, who could not be reached for an interview, has said many times he believes the only way man would return to the moon was through the private sector, not the government. But it appears the U.S. is committed to send people to the moon again, Neufeld said.

Neufeld said the Artemis 1 mission's goal is to lead to a program "to stay on the moon permanently and build a base and figure out if we can use the resources on the moon to make it sustainable." He said humans will never learn to visit any planet or site in the solar system without learning how to live in space first. The moon is the perfect training ground for that, he said.

But in 1972, after Schmitt and Apollo 17 returned to earth, it looked like man would never go to the moon again, let alone Mars.

A rocky start, but that's OK

Born in 1935 in the now-uninhabited community of Santa Rita, near Silver City, Schmitt, through his geologist father, found a love of rocks as well as meteorology. He remained fascinated by studying the weather throughout his life.

In 2015, Schmitt told KOAT-TV he was a nerd in high school, though he also played football and got involved in student government groups. His father suggested he study geology and engineering at the California Institute of Technology. He did so and also studied at the University of Oslo and Harvard University.

He was working for the U.S. Geological Survey in Flagstaff, Ariz., in the early 1960s when he saw an ad calling for scientists to join the National Aeronautics and Space Administration.

"Why not raise your hand and volunteer?" he asked himself. "So I volunteered."

He joined at just the right time. The Apollo program had evolved from the Mercury program and the space race of the late 1950s and early '60s, with the U.S. and Soviet Union competing to see who could get to the moon first. After a sluggish start, Americans crossed the finish line ahead of their Cold War archrivals, with Apollo 11 touching down on the moon's Sea of Tranquility in July 1969.

But by 1972, when Schmitt readied to fly on Apollo 17, interest in and support for the space program had waned.

"It's very easy to lose the American public's interest when you get good at something," Orwoll said.

For many Americans, Apollo 17 became "just another moon landing, so it wasn't followed as closely as Apollo 11," he added.

Schmitt was scheduled to fly on Apollo 18 until NASA announced it was canceling the Apollo program after Apollo 17. NASA shifted him into place following pressure from the scientific community to get a scientist on the moon.

"You have a lunar geologist on an astronaut crew; you should let him fly," Neufeld said, echoing the feeling of scientists at the time.

After a lengthy training period, the launch was set for the evening of Dec. 7, 1972. Before the computer malfunction that briefly delayed the blastoff, Schmitt recalled in a 2000 interview for the NASA Johnson Space Center Oral History Project, "the rocket, you could feel it. You're lying there on your back, you could feel the engines moving down a football field below you or more as it prepared for ignition."

The trip took 3 1/2 days, with the ship landing Dec. 11. Though the crew discussed resting up a bit before exiting the craft, Schmitt said in the 2020 interview, "You're just so keyed up, you want to go outside."

He vividly recalled in several interviews his first thought upon climbing down the craft's ladder to the surface: "Oh, don't fall." That's because he slipped and missed a step on the ladder. Apollo 17 had landed in a canyon area known as Taurus — Littrow, which, Schmitt said, was deeper than the Grand Canyon.

Cernan stepped onto the moon's surface first, saying, "I'm on the footpad. And, Houston, as I step off at the surface at Taurus — Littrow, we'd like to dedicate the first step of Apollo 17 to all those who made it possible."

During their approximately 75-hour stay on the lunar surface, Cernan and Schmitt drove a lunar roving vehicle to nine pre-planned locations to collect samples.

Schmitt's geological curiosity was heightened by scientific discoveries along the way. He was, in a sense, in a geologist's playland.

"We found the oldest rock that's been sampled on the moon ... we found the orange soil, which is really stirring things up this day and age, because it makes it very difficult to explain how the moon might have formed by a giant-impact of a Mars-sized asteroid on the Earth [as some earlier theories suggested]," he said in the 2000 interview.

Their findings, he said, led to "a better understanding of the earth, the origin of the Earth and the evolution, particularly in that period of time when life was trying to get started here."

The trip back, like most trips back from somewhere exciting, was unexciting, he recalled. Apollo 17 returned to earth on Dec. 19. Schmitt would later convey disappointment when then-President Richard Nixon publicly proclaimed the mission might be the last time men walked on the moon in the 20th century.

"It was an unnecessary thing to say to the young people of the country," Schmitt said in the 2000 interview. "It was stupid."

It was also true.

Schmitt, elected to the U.S. Senate four years after his moonwalk — he was defeated in a run for reelection in 1982 — has continued to advocate for moon and space exploration and harnessing potential energy sources from the heavens for renewable energy purposes on Earth.

He is a member of what may be the most exclusive club on the planet — and one that's shrinking. Only four moonwalkers are still alive.

Asked in the KOAT interview if he brought back anything special for himself from the moon, Schmitt said, "The special things I have are memories. Everything else is really something the taxpayer paid for and owns. ... My benefit are the memories."