TENERIFE, SPAIN — Commander Reid Wiseman and the Artemis II crew briefly feared they might never make it home after the Orion spacecraft passed its planned maximum distance from Earth during the mission’s journey around the moon.

The Integrity spacecraft was expected to reach 219,667 nautical miles (252,788 miles, or 406,823 kilometers) from Earth — farther than any human being had traveled before. But when the spacecraft’s odometer continued to rise beyond that point, the astronauts began to worry that something had gone wrong.

Wiseman described the tense moment to an audience at the Starmus VIII Festival in Tenerife, Spain. The biennial event celebrates achievements in science, exploration and creativity.

The spacecraft passed its expected maximum distance

“The controllers in Houston told us our maximum range was 219,667 nautical miles, which was the furthest we were expected to go from Earth,” Wiseman said.

“I was looking at the numbers, and I saw 219,667, and I thought, ‘Wow, this is the farthest point from Earth, and the next number I see is going to be 219,666, and we’re going home.’”

But after about three minutes, the number did not fall. Instead, the odometer showed 219,668 nautical miles. Then it rose again to 219,669.

“That’s when I got really scared,” Wiseman said. “I thought I had gone too far. I can’t go back home. So I was very scared.”

Artemis II crew waited for the number to drop

While Wiseman watched the spacecraft’s distance from Earth, NASA astronauts Victor Glover and Christina Koch were at the window conducting scientific observations of the moon. Canadian Space Agency astronaut Jeremy Hansen was sending a report back to mission control, so Wiseman’s moment of terror went unnoticed by the rest of the crew.

Finally, the odometer began to count down. When Wiseman saw it return to 219,668 nautical miles, he said, “I’m going home,” and the crew cheered.

“We knew we had a good chance of success,” he added.

Artemis II returned safely to Earth

In an interview with The Week Junior Science + Nature, Wiseman praised NASA’s Earth-based teams for helping make the mission a success.

“Our successful return is a testament to the engineering rigor and flight control team that assembled this rocket and brought it back to Earth,” Wiseman said. “When we went to the moon and back, they are the true heroes of this mission. They’re really brave.”

The Artemis II mission launched on April 1 from NASA’s Kennedy Space Center in Florida. It was the first crewed flight of the Orion spacecraft and the first crewed flight to the moon since Apollo 17 in 1972. The mission took almost 10 days to fly around the far side of the moon and return to Earth.

Nearly every moment of the crew’s activities inside Orion was livestreamed to the world, generating significant public interest. The Artemis II crew later won the Stephen Hawking Award for Science Communication at the Starmus VIII Festival.

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