The second-ever private astronaut mission to the International Space Station (ISS) remains on track to lift off this weekend.
NASA, SpaceX and Houston company Axiom Space held a flight readiness review (FRR) today (May 15) for the Ax-2 mission, which is scheduled to launch four people toward the International Space Station on Sunday afternoon (May 21).
"At the end of that review, the full team polled 'go,'" Ken Bowersox, associate administrator for NASA's Space Operations Mission Directorate, said during a post-FRR press conference this afternoon.
If all goes according to plan, Ax-2 will launch atop a SpaceX Falcon 9 rocket at 5:37 p.m. EDT (2137 GMT) on Sunday from NASA's Kennedy Space Center (KSC) in Florida. The Ax-2 astronauts will ride a SpaceX Dragon capsule to the orbiting lab, getting there around 9:30 a.m. EDT (1330 GMT) on Monday (May 21).
The mission will spend eight days docked to the ISS, team members said today. That's a slight change from the previous plan, which had called for a 10-day ISS stay.
If Ax-2 can't get off the ground on Sunday, it has another chance on Monday (May 22). If the mission misses that backup opportunity, however, it will have to wait a while to get to space: NASA and SpaceX will then shift toward preparing for the launch of CRS-28, SpaceX's 28th robotic cargo mission to the ISS, which is slated to lift off from KSC on June 3.
"And then, at that time, Axiom, NASA and SpaceX will get together and look for the next best opportunity as we look at the missions that we have this summer," Joel Montalbano, manager for NASA's International Space Station Program, said during today's telecon.
Those other flights include crewed jaunts to the ISS such as Boeing's Crew Flight Test (currently targeted for July 21) and SpaceX's Crew-7 mission, as well as "other missions that use the pad facilities at Kennedy Space Center," Montalbano said.
As its name suggests, Ax-2 will be the second crewed flight to the ISS operated by Axiom Space using SpaceX hardware. The first, Ax-1, sent four people to the orbiting lab for more than two weeks in April 2022.
Ax-2 is groundbreaking in its own way as well. Two of the mission's crewmembers are Rayyanah Barnawi and Ali AlQarni, who will become the first Saudi Arabians to visit to the ISS. Barnawi will be the first Saudi woman ever to reach space.
The other crewmates are investor and paying customer John Shoffner and former NASA astronaut Peggy Whitson, who now works for Axiom and will command the mission. Whitson has racked up a total of 665 days off Earth — more than any other American and any other woman.
NASA currently requires that all private astronaut flights to the ISS be led by a former agency spaceflyer. Ax-1 was commanded by Michael López-Alegría, who racked up four spaceflights while working for NASA.
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Michael Wall is a Senior Space Writer with Space.com and joined the team in 2010. He primarily covers exoplanets, spaceflight and military space, but has been known to dabble in the space art beat. His book about the search for alien life, "Out There," was published on Nov. 13, 2018. Before becoming a science writer, Michael worked as a herpetologist and wildlife biologist. He has a Ph.D. in evolutionary biology from the University of Sydney, Australia, a bachelor's degree from the University of Arizona, and a graduate certificate in science writing from the University of California, Santa Cruz. To find out what his latest project is, you can follow Michael on Twitter.