NASA’s Artemis II crew are the fastest people alive, and now they have the patch to prove it.

Mission Commander Reid Wiseman, pilot Victor Glover, and mission specialists Christina Koch and Jeremy Hansen (the latter with the Canadian Space Agency) spent 10 days in early April flying by the Moon. Their journey took them farther away from Earth than any humans have gone (52,756 miles [406,771 km]) and then, on the way back on board their Orion spacecraft Integrity, they sped up to about 24,664 miles per hour (39,693 k/ph) reentering the atmosphere.

Only three other people in history have traveled faster. NASA’s Apollo 10 astronauts Thomas Stafford, John Young, and Eugene Cernan set the record for the highest speed attained by a crewed vehicle relative to the Earth’s surface: 24,791 mph (39,897 kph) on May 26, 1969.

Cernan died in 2017, Young in 2018, and Stafford in 2024.

“The number that we saw on the displays—and I was very in tune with what Orion thinks it is going to do—was 38.89 as the Mach. But it depends on how you measure that number. It is actually challenging how you measure from space,” said Glover at the crew’s post-flight press conference at NASA’s Johnson Space Center in Houston on April 16, six days after landing.

Mach, as a measurement, compares the speed of an object to the local speed of sound. So the number changes based on altitude, air temperature, and air density. At sea level, 24,664 mph would be Mach 32, or 32 times the speed of sound.

At the point where the Artemis II crew reached peak velocity, the air was thinner and the temperature was colder than at sea level.

Mach 39

“There will be a new [Mach patch] coming out when we figure it out,” Glover said.

It took three weeks (including the time for NASA’s embroidered patch supplier, A-B Emblem in Weaverville, North Carolina, to produce it for the crew) but the Mach 39 patch made its public debut on Friday (June 5) in a video posted on social media by Wiseman. That is, if you were paying attention for such details.