After two astronauts were stranded on the International Space Station since June, it could be months before they return to Earth – partly because of incompatible spacesuits.
The two astronauts Butch Wilmore and Suni Williams had to extend their eight-day stay on the ISS because their Boeing-built Starliner spacecraft had a helium leak and engine malfunctions. NASA and Boeing are currently testing whether it is safe for the astronauts to return with the Boeing Starliner, but are also considering alternatives in view of the potential risks.
NASA has not yet made a decision, but one of the alternatives is to send the astronauts home in a Dragon spacecraft built by Elon Musk’s SpaceX that is already docked at the station, a spokesperson for the space agency said during a press conference last week, Ars Technica reported.
But that approach comes with complications, as Swapna Krishna, the journalist behind space YouTube channel Ad Astra, explains. If NASA chose that option, Wilmore and Williams would be the fifth and sixth astronauts in a spacecraft limited to four passengers. And since their Starliner suits aren’t compatible with the Dragon spacecraft, they would have to return to Earth without suits, which, while not necessarily dangerous, offers them less protection if something goes wrong with the capsule.
The different suit designs and connectors for the Starliner and Dragon spacecraft are due to a new process for commercial manned space missions that NASA has introduced. Previously, NASA was heavily involved in the manufacturing and testing of spacecraft and spacesuits.
But since NASA developed the Commercial Crew Program in the 2010s, it has given private companies more freedom to design and manufacture equipment for the agency, including spacesuits, as long as they meet general safety requirements. For example, NASA has not specified that the spacesuits for each commercial spacecraft must be compatible with each other. In fact, Krishna says it could be beneficial to have two different suit designs for each spacecraft.
“If the suits used the same type of connector and a fault was found in that connector or any other type of standardized connector, both spacecraft would be grounded,” she said in a video on Sunday.
A Boeing spokesman referred a request for comment to NASA. NASA and SpaceX did not immediately respond to requests for comment. NASA has said the astronauts were not “stranded” on the ISS.
Another alternative is to send the astronauts home on another Dragon spacecraft, scheduled to reach the ISS in September. That craft could reach the space station with only two of its usual four crew members and send along extra (Dragon-compatible) spacesuits that would allow Wilmore and Williams to return to Earth fully equipped in the two vacant seats.
However, if NASA were to choose this alternative, the Starliner spacecraft that the astronauts originally flew on would have to undock and return to Earth on its own to make way for the Dragon spacecraft, which arrives in September. Boeing has said it may not be able to do this. Boeing’s contract structure with NASA required the company to absorb the additional costs associated with the technical failures of its Starliner. The company has already recorded costs of around $1.6 billion for its Starliner program.
If the Starliner were to leave the space station without a crew, the astronauts on the ISS would also have to install two additional seats in the remaining Dragon space shuttle until the next Dragon arrives, because the remaining docked ship must provide enough seating to accommodate all NASA astronauts in an emergency.
The stranded astronauts would have to take the place of the two astronauts pulled from the Dragon mission to accommodate them, which would keep them aboard the ISS until the regular rotation ends in February 2025. That would mean extending the planned mission from just over a week to eight months. Although both astronauts have previously completed longer missions on the ISS, those have been fraught with less uncertainty. Wilmore’s wife told a CBS station in Knoxville that she is preparing for her husband to miss Christmas and the couple’s 30th wedding anniversary.
This story originally appeared on Fortune.com
