It had been planned as a historic mission, yet it would have represented a moment of sort: the first all-female spacewalk.
But that moment will have to wait, NASA said Monday, because of a somewhat basic issue – spacesuit sizes
The two astronauts who were scheduled to walk together in space on Friday, Anne C. McClain and Christina H. Koch, would both need to wear a medium-size torso component. But only one is available at the International Space Station.
The mission itself is unchanged. On Friday, two astronauts will venture outside of the space station on a six-hour mission to install massive lithium-ion batteries that will help to power the research laboratory. Ms. Koch is still scheduled to participate, along with her fellow astronaut Nick Hague; Ms. McClain did her first spacewalk last week
Stephanie Schierholz, a spokeswoman for NASA , said in an interview on Monday that there were already two medium-size hard upper torsos – "essentially the shirt of the spacesuit," according to NASA – at the space station.
But there were a couple of issues. One was that Ms. McClain had thought she would be able to work in a large-size torso, but after her spacewalk last Friday, she was a medium-size torso and learned that it fit her better. Ms. Also uses the same size.
And of the two medium-size torsos available, one has yet to be properly configured for a spacewalk. It would take hours of crew labor – not to mention some additional risk – to fix that in time for Friday. Instead of doing that, NASA decided to simply switch out the astronauts
In the end, both women will have done a spacewalk – just not together. 19659002] "When you have the option of just switching the people, the mission becomes more important than a cool milestone," Ms. Schierholz said.
[ Sign up to get reminders for space and astronomy events on your calendar .] On Friday, Ms. Koch and Mr. Hague will be supported by a team on the ground that includes a number of women in key positions, including the spacewalk's flight director, Mary Lawrence, and its lead officer, Jackie Kagey.
In a briefing at NASA's Johnson Space Center in Houston this month, Ms. Lawrence, Ms. Kagey and Kenneth Todd, the station's operations integration manager, said officials had not immediately recognized the significance of the original lineup for Friday's "extravehicular activity," or EVA.
It was only as they discussed the schedule during a meeting they realized it was the first time they had scheduled an all-female spacewalk.