Falcon 9 and SLS
A Falcon 9 carrying the Crew Dragon spacecraft for the Ax-1 mission to the ISS stands on the pad at Launch Complex 39A with the first Space Launch System rocket in the background at Launch Complex 39B. Credit: NASA/Joel Kowsky

COLORADO SPRINGS — The first commercial mission by an American spacecraft to the International Space Station is ready for launch as a pathfinder for a new era of commercial orbital human spaceflight.

At an April 7 briefing, officials from NASA, Axiom Space and SpaceX said the Falcon 9 launch vehicle and Crew Dragon spacecraft are ready for launch at 11:17 a.m. Eastern April 8 from Launch Complex 39A at the Kennedy Space Center. Forecasters are projecting a 90% chance of acceptable weather for the launch.

One issue still being looked at is weather at abort locations along the vehicle’s ascent to orbit off the East Coast and into the North Atlantic. Benji Reed, senior director of human spaceflight programs at SpaceX, said weather in those locations “was starting to trend a little bit better” after earlier concerns they might violate constraints involving conditions like wind and sea state. “A handful of those points that were looking no-go have now trended towards go,” he said.

If Ax-2 does not launch April 8, there are additional launch opportunities April 9 or 10. Should the launch be delayed further, NASA officials said they would negotiate with the Space Launch System program, which is preparing for another attempt at a fueling test and countdown rehearsal as soon as April 11.

The mission, called Ax-1, will transport four private astronauts to the ISS for an eight-day stay. Michael López-Alegría, an Axiom employee and former NASA astronaut, will command the mission, with three customers on board: Larry Connor, Mark Pathy and Eytan Stibbe.

While nonprofessional astronauts have visited the station intermittently for more than two decades, all previous visits involved Soyuz missions to the station. Those missions also all had at least one government cosmonaut on board. Ax-1, by contrast, is the first involving an American spacecraft and the first crewed entirely by private individuals rather than government employees.

Derek Hassmann, operations director at Axiom, described Ax-1 as a “precursor mission” for the company’s long-term plans, which include installing a series of commercial modules at the ISS that would later serve as the core of a stand-alone space station. “We’re going to build our relationships both with NASA and with SpaceX. We’re going to demonstrate the capabilities that NASA brings to the table,” he said.

The mission is also a pathfinder for NASA as it gets used to having commercial astronauts on the U.S. segment of the ISS, which they rarely visited on past Russian missions. “They’ve come over to the U.S. segment, but their interest is usually in two different things. One is using our cupola so they can get great photos out of the window, and the other is using email,” said Dana Weigel, NASA ISS deputy program manager. “Our experience to date is really, really limited.”

Axiom and NASA worked closely on various aspects of the mission, from the amount of training needed for the Ax-1 crew on ISS systems to determining what consumables and other cargo they needed to bring with them to the station. Ax-1, for example, will use some station resources like oxygen, compensating NASA for them, rather than being completely self-sufficient as originally proposed.

“From our point of view, we’re really looking at this in terms of what do commercial missions want to look like,” said Angela Hart, manager of NASA’s commercial LEO program. “What are the customer needs, what are the markets that are interested. We are going to learn a lot from there.”

Both Axiom and NASA said they were committed to working together on this mission and using the lessons learned to inform future missions. Axiom has a NASA agreement for its Ax-2 mission, another Crew Dragon flight to the ISS, in early 2023. NASA plans to seek proposals for additional private astronaut missions after Ax-1 flies.

“The space station team is really excited for this first-of-its-kind mission and also to be on the leading edge of helping to commercialize low Earth orbit,” Weigel said, adding that interest extended to the astronauts on the ISS itself. “They’re really excited to welcome the Axiom crew on board, and excited to get to be a part of this first-time, historic mission.”

“They want to be the best possible private astronauts that you can imagine,” Hassmann said of the Ax-1 crew. “They want to be good house guests, if you will.”

Jeff Foust writes about space policy, commercial space, and related topics for SpaceNews. He earned a Ph.D. in planetary sciences from the Massachusetts Institute of Technology and a bachelor’s degree with honors in geophysics and planetary science...