NASA and SpaceX are preparing to launch a new four crew to the International Space Station on Wednesday evening to relieve the station’s current crew, including the two astronauts who originally launched on Starliner.
The international crew consists of two American astronauts, a Japanese Aerospace Exploration Agency (JAXA) astronaut and a Russian cosmonaut. They will fly to the orbiting outpost onboard the Dragon Endurance spacecraft, which previously flew the Crew-3, Crew-5 and Crew-7 missions.
Liftoff from Launch Complex 39A at NASA’s Kennedy Space Center set for 7:48 p.m. EDT (2348 UTC). If needed, backup opportunities are available on Thursday and Friday as well.
Spaceflight Now will have live coverage beginning about four hours prior to liftoff.
NASA astronaut Anne McClain will lead the crew on a short transit to the ISS. If launch occurs Wednesday evening, Dragon would dock with the forward port of the space station’s Harmony module about 6 a.m. EDT (1000 UTC) on Thursday.
McClain, along with fellow NASA astronaut Nichole Ayers, JAXA astronaut Takuya Onishi and Roscomos cosmonaut Kirill Peskov, will live and work on the space station for a roughly six-month period to conduct scientific and technological demonstrations.
Following a launch readiness review and an additional flight readiness review on Tuesday, NASA didn’t host a press conference, as is customary, but instead posted an update to its Crew-10 mission blog.
“Over the past six weeks, the joint NASA, SpaceX team has displayed remarkable dedication, adaptability, and expertise in delivering on a unique and challenging mission,” said Steve Stich, CCP manager, in that post. “Throughout this intense period, I am immensely proud of the collective effort put forth to resolve late breaking technical issues, adjust operations as needed, and keep safety at the forefront of everything we do.”
Because of delays to the readiness of the fifth Crew Dragon spacecraft to debut, tail number C213, NASA and SpaceX made the decision to instead fly Dragon Endurance instead. This will be its fourth flight after previously supporting the launches of Crew-3, Crew-5 and Crew-7.
SpaceX’s Falcon 9 rocket and Crew Dragon Endurance stand at Launch Complex 39A at NASA’s Kennedy Space Center ahead of the launch of the Crew-10 mission to the International Space Station. Image: Michael Cain/Spaceflight Now
In its post-flight readiness review teleconference on Friday, Stich said there were some degradation issues with some thrusters on Endurance and other additional work that needed be closed out ahead of launch.
“SpaceX completed supplemental ground testing over the weekend, demonstrating Draco thruster performance with reused engine coatings that protect the thruster from oxidation,” NASA wrote. “Following successful testing, data analysis and flight rationale were presented and accepted by NASA.”
The Falcon 9 first stage booster launching the Crew-10 flight, tail number B1090, will be making its second flight to space and back. It first flew on Dec. 17, 2024, carrying the seventh and eighth O3b mPOWER satellites to medium Earth orbit for satellite communications company, SES.
One of the watch items for NASA and SpaceX coming into the Crew-10 launch was a fuel leak that sprang up mid-ascent during the Starlink 12-20 mission on March 2. That led to a fire in the engine section less than a minute after touchdown on the droneship, ‘Just Read the Instructions’ and ultimately, the destruction of that booster, tail number B1086.
NASA wrote that it received a summary of the findings stemming from SpaceX’s investigation into the fuel leak mishap and combined that with data gathered during a static fire test of B1090 conducted on Sunday, March 9. Following that static fire, NASA said it inspected the engine bay of that booster and performed a “sniff” check to test for signs of leaks.
“NASA leaders determined that while the root cause of the Starlink post-landing fire is still under review, there is sufficient evidence to provide clearance to proceed with the crewed launch,” the agency wrote.
After publication of NASA’s blog post, on Tuesday night, SpaceX also launched NASA’s SPHEREx and PUNCH mission to a Sun-synchronous, polar orbit. The Falcon 9 first stage booster on that mission, tail number B1088, returned for a touchdown at Landing Zone 4 at Vandenberg Space Force Base with no reported issues.
Practicalities and politics
Once onboard the space station, there will be a relatively short handover period between Crew-10 and Crew-9. Normally, this would take place over roughly five days, but it’s being shortened due to concerns about commodities onboard the ISS.
During NASA’s briefing on Friday, Dana Weigel, NASA’s ISS program manager, noted that the upcoming cargo resupply mission being managed by Northrop Grumman using its Cygnus spacecraft, encountered an issue. She said that the spacecraft’s shipping container sustained some damage as it was being brought to the Cape.
Because she said it’s a “critical resupply mission,” as a precautionary measure, they are changing the manifest for SpaceX’s CRS-32 mission, which is scheduled to launch in mid-April. That will allow it to bring up more food and other commodities for the ISS.
The shift also means that a shorter handover was determined to be the best course of action.
“We shortened that for two days just to conserve consumables onboard and what that really does for us is it just opens up more undock opportunities,” Weigel said. “So, we have a chance to find a good weather opportunity for undock to minimize how long we have additional crew on board.”
Weigel said the Northrop Grumman flight, named NG-22, was originally scheduled to fly in January and then February, but it was delayed until June after into an avionics issue.
The return of the Crew-9 quartet also means that NASA astronauts Butch Wilmore and Suni Williams, the former crew of the Boeing Starliner Crew Flight Test mission, will be returning to Earth later this week.
The decision to keep them onboard the space station and return the CST-100 Starliner spacecraft uncrewed became a flashpoint in the political world when SpaceX founder, political donor and advisor to the President, Elon Musk made a series of claims on his social media site, X, regarding the particulars of Wilmore and Williams’ return.
He claimed, without providing evidence, that there was an offer made from SpaceX to the White House under then President Joe Biden to fly an extra Dragon mission to the ISS just to retrieve Wilmore and Williams.
The comments were bolstered by those from President Donald Trump who falsely claimed that the two astronauts were “stuck” on the space station and were “abandoned” by the Biden administration.
NASA leadership made the decision in late summer 2024 that Starliner had enough outstanding concerns that it made more sense to bring it back without its crew and to have Wilmore and Williams return as members of the Crew-9 flight instead.
For their part, Wilmore and Williams have also refuted the idea that they were left behind or abandoned.
“We have both been in the military, both Navy guys, our deployments have been extended,” Williams said in a recent interview with CBS News. “You do what’s right for the team, and what was right for the team is to stay up here and be expedition crew members for the International Space Station.”
