The second fully commercial astronaut flight to the International Space Station will have just two chances to launch on Sunday and Monday, or wait until after SpaceX’s next resupply mission next month to deliver a new batch of high-priority solar arrays to the complex.

The private crew mission, operated by Houston-based Axiom Space, is scheduled to lift off at 5:37 p.m. EDT (2137 UTC) Sunday from Launch Complex 39A at NASA’s Kennedy Space Center in Florida. The four-person crew will ride into orbit aboard a SpaceX Falcon 9 rocket and Dragon spacecraft.

Record-breaking astronaut Peggy Whitson, who has spent more time in space than any other American, leads the crew. She retired from the NASA Astronaut Corps in 2018 after three long-duration missions on the space station, totaling 665 days in orbit.

She will be joined by American businessman John Shoffner, who paid for his seat on the Axiom-sponsored flight to the space station. Saudi astronauts Ali Al-Qarni and Rayana Barnawi are scheduled to fly as mission specialists on the Ax-2 mission, which is expected to last 10 days.

Al-Qarni and Barnawi will be the first Saudis to travel to the International Space Station, and Barnawi will be the first Arab woman on an orbital research site. Their mission is funded by the government of Saudi Arabia.

During their time in orbit, Whitson, Shoffner, Qarni, and Bernawi will conduct biomedical experiments, chemistry and materials research, and educational events with students on the ground. They will also greet and spend time with the seven crew members who live on the station for extended periods.

The Ax-2 mission is the second Axiom crew mission, following the company’s April 2022 Ax-1 flight that made history as the first all-private astronaut crew to reach the space station. NASA provides resources on the space station for commercial astronaut missions such as Axiom flights, but Axiom, and ultimately private crew members or their sponsors, must pay NASA for training and crew accommodations, such as access to the station’s life support system, and food. , and toilet.

The cost of the seat has not been released, but the NASA Inspector General has estimated the price of a seat on a SpaceX Dragon spacecraft at about $55 million for NASA astronauts. It is not known how this compares to the price of a fully commercial seat.

Until now, NASA has requested private astronaut missions to the station piloted by a former professional astronaut. Retired NASA astronaut Michael Lopez-Alegria commanded the Ax-1 mission last year.

One of her roles, Whitson said, is to guide her three crewmates, all newbies to spaceflight, on the do’s and don’ts of living and working on the space station.

“I shared a long list of what we would do, what we wouldn’t do, how we would do things, and the reasons behind it all,” she said. “There are a lot of lessons learned after being in space for 665 days, I had a lesson or two that I probably learned the hard way, and I try to save some time because our mission is relatively short. So we want to make sure we get the most out of each of those days.”

Previous visits to the space station by private astronauts, or “space tourists,” have been on government-led missions aboard Russian Soyuz spaceships. Prior to the Ax-1, 11 people had flown to the space station as payment to passengers on Soyuz missions, but they all traveled with a cosmonaut commander who was a government employee.

Axiom has contracted with SpaceX to launch the Falcon 9 and Dragon flight to the space station. Axiom plans to fly a third private astronaut mission to the space station late this year, also launching it on a SpaceX rocket.

NASA has an agreement with Axiom to build and launch a commercially owned module to the International Space Station sometime in late 2025. Eventually, Axiom plans to build a self-contained private space station in low Earth orbit. NASA wants to have a commercial orbital outpost ready to take over the kind of research being done on the International Space Station by the time it retires in 2030.

SpaceX orbited a Falcon 9 rocket with its Dragon Freedom capsule to launch Complex 39A on Thursday, then lifted it vertically for a test of its main engines on Friday, leading up to a countdown and launch on Sunday.

But the target launch date for the Ax-2 mission from earlier this month has been pushed back, compounded by scheduling slip-ups on an earlier SpaceX mission. The Falcon Heavy rocket that was supposed to launch in early April didn’t lift off from the same launch pad until April 30 after a series of delays caused by technical problems and bad weather. It takes SpaceX about three weeks to reconfigure the launch pad from the Falcon Heavy mission into a crewed flight on the Falcon 9 rocket.

This delayed the launch of the Ax-2 until Sunday, May 21. By mission Ax-2.

NASA gave Axiom and SpaceX two days, Sunday and Monday, to get the Ax-2 mission off the ground before the space agency directed SpaceX to turn their attention toward preparing for the June 3 resupply launch. NASA has a say in both missions as they head to the space station.

Axiom has already shortened the Ax-2 mission’s stay at the space station from 10 days to eight days to allow the flight to fit into NASA’s schedule before SpaceX’s resupply mission next month. Assuming the mission launches on Sunday, the Dragon Freedom spacecraft will dock at the station on Monday, then depart on May 30 to head out for a parachute-assisted flight off the coast of Florida.

“Ultimately, there was no impact on the research goals,” said Derek Hussmann, head of Operations Integration and Operations at Axiom. “There was some media outreach and other things that we wanted to do, but weren’t high priority, abandoned. But all the high priority goals we were able to fit into that eight-day schedule.”

Next month’s Cargo Dragon flight will deliver two upgraded solar arrays to the space station. Installing and deploying the new solar panels will require one or two spacewalks by the station’s astronauts, along with use of the lab’s Canadian robotic arm.

There is a period of high angle sun on the space station in early July, so NASA wants the solar array work to be complete by then. This will be followed by the scheduled July 21 launch of Boeing’s Starliner crew capsule for the first crewed test flight to the station. SpaceX also plans to launch more Falcon Heavy rockets for the US Space Force and a commercial customer this summer from Platform 39A, and SpaceX’s next NASA-contracted crew flight is scheduled to launch from Platform 39A in August.

All in all, that leaves little opportunity to fit the Ax-2 mission this summer into a busy schedule of missions to the space station, and into SpaceX’s busy launch schedule from Kennedy Space Center. If the mission doesn’t fly on Sunday or Monday, it’s not clear when the Ax-2 will have another chance at launch.

“Right now, we’re looking at May 21st and 22nd,” said Joel Montalbano, NASA Program Manager for the International Space Station. “If we don’t go down by the 22nd, we’re going to pull out with the Axiom-2 mission and shift our focus to the SpaceX (cargo) mission.” And then, at that time, Axiom and NASA and SpaceX will get together and look for the next best opportunity as we look at the missions that we have. summer, which not only sends missions to the International Space Station, but other missions that use the pad facilities at Kennedy Space Center.”

Sunday’s weather forecast shows a good chance that conditions will allow the Falcon 9 launch of the Ax-2 mission. There is a 60% chance of favorable weather taking off on Sunday.

But weather patterns tend to be wetter early in the week, with an 80% chance Monday that a thunderstorm could violate one or more of the Falcon 9 rocket and Crew Dragon spacecraft launch commitment criteria.

The Ax-2 mission will be SpaceX’s tenth human spaceflight mission, but it does come with a few initiatives. The launch will debut the new Falcon 9 booster, tail number B1080, on its first flight into space.

For the first time in a crewed launch, SpaceX will return the Falcon 9 booster back to the landing area at Cape Canaveral Space Force Station. For all of the crew’s nine previous launches, the vehicle has landed on an unmanned ship at sea, which has taken the rocket back to Florida for refurbishment and reuse.

The company’s high launch rate showed the Falcon 9 rocket had some additional performance to enable the booster’s return to Florida for landing, said Bill Gerstenmaier, SpaceX’s vice president of construction and flight reliability. The return maneuver requires additional burn by the rocket’s engines, which means it needs more fuel left in the tanks after the booster completes its main task of sending the Dragon crew capsule into space.

SpaceX has managed to outperform the Falcon 9 rocket on Starlink missions without major modifications to the engines or other hardware.

“We’ve been able, on the Starlink missions, to show that we have an additional capability for us to go forward and benefit from this mission,” Gerstenmaier said. “We’ve always had this kind of capability before, and we weren’t sure we’d always get the performance, but the number of Falcon flights we’ve taken has allowed us to say that this performance is available and can be used where it needs to be used going forward.”

Gerstenmaier said it’s “helpful” for SpaceX to bring the rocket back to Earth, rather than aiming it at the drone ship in the Atlantic. It eliminates the need to worry about weather or sea conditions at the drone ship’s location, freeing recovery vessels for other tasks.

“That’s great in the fact that this is a new booster, the first flight booster, that we’re going to fly here, Booster 1080,” Gerstenmaier said. “It would be nice to see it in service, and we expect it to have a long life and serve multiple missions in the future.”

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