NOEL KING, HOST:
Two NASA astronauts, Christina Koch and Jessica Meir, are replacing a piece of hardware that controls the power on the International Space Station this morning. It's a routine spacewalk, but down here on Earth, people are celebrating a milestone.
From member station WMFE, Brendan Byrne has the story.
BRENDAN BYRNE, BYLINE: It's the first all-female spacewalk. And space policy analyst Laura Forczyk is celebrating.
LAURA FORCZYK: Of course I'm excited that they're both women. An all-female spacewalk has been long overdue.
BYRNE: A previous attempt at an all-female spacewalk was scrapped back in March, when the correct-sized spacesuits for the would-be walkers couldn't be ready in time. Instead, a male and female astronaut performed the task. NASA's Megan McArthur says all four NASA astronauts on board the station now - two women and two men - can perform the power replacement task. But...
MEGAN MCARTHUR: I think the fact that it will be two women just is a reflection of the fact that we have so many capable, qualified women in the office and, you know, many coming in through the different career channels that bring them into the astronaut office.
BYRNE: Women have been spacewalking for decades. The Soviet Union's Svetlana Savitskaya, followed shortly by NASA's Kathryn Sullivan, became the first woman spacewalkers back in 1984 on separate missions. And since then, more than a dozen women have ventured outside in space. But self-described friends Koch and Meir understand the significance of their scheduled walk. Here's Koch speaking from the station.
CHRISTINA KOCH: In the past, women haven't always been at the table. And it's wonderful to be contributing to the human spaceflight program at a time when all contributions are being accepted, when everyone has a role.
BYRNE: Floating next to Koch inside the station, Meir agrees.
JESSICA MEIR: What we're doing now shows all of the work that went in for the decades prior, all of the women that worked to get us where we are today. And I think the nice thing is, for us, we don't even really think about it on a daily basis. It's just normal. We're part of the team. We're doing this work as an efficient team, working together with everybody else. So it's really nice to see how far that we've come.
BYRNE: Some have criticized NASA and the media for the recent focus on gender diversity in spaceflight when women have been in space for decades. Retired NASA astronaut Nicole Stott has lived in space more than 100 days and participated in a spacewalk back in 2009. She's worked to get more women into engineering and the astronaut corps.
NICOLE STOTT: We train astronauts as astronauts. Doesn't matter what flavor you are. I love seeing now that we are in a place where we have a much larger balance of women and men in the office.
BYRNE: For NPR News, I'm Brendan Byrnes.
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