NASA reached a milestone on Friday morning when two Americans ventured out of the International Space Station to replace a power controller: The astronauts, Jessica Meir and Christina Koch, had undertaken the first all-female spacewalk.
Such a walk was supposed to take place in March, but it was postponed because NASA did not have two appropriately sized spacesuits available. That sparked an outcry — and a “Saturday Night Live” spoof — about the legacy of sexism in the space program.
More recently, Ms. Meir and Ms. Koch had planned to install lithium-ion batteries on Oct. 21, but the timeline was hastened after a power controller failed last weekend. The controller, which regulates the batteries that distribute power to the station, had been in operation for 19 years and will be replaced. The agency said the failure had no impact on the crew’s safety or continuing experiments.
Friday’s spacewalk was the seventh this year. By the end of December, NASA expects to have conducted more spacewalks than it has in any year since 2010, but the schedule depends on what the agency determines about the power controller failure.
Ms. Koch emerged first from the space station, followed by Ms. Meir. Both women were outside of the station shortly before 8 a.m. Eastern time, and NASA was streaming the process live.
Here’s what happened in March
Ms. Koch had been scheduled to carry out a March 29 spacewalk with Anne McClain, a decorated astronaut and lieutenant colonel in the Army.
But both of the women needed medium-size torso components for the spacewalk, and only one was available. Ms. McClain said she had initially thought she would be able to work in a larger size. But after doing a spacewalk in a medium size with her colleague Nick Hague on March 22, she realized that was a better fit. There was not enough time to properly configure a second medium-size torso component, and Ms. McClain recommended sending Mr. Hague in her place.
For some observers, the change underscored the challenges faced by women in the space program and other fields where equipment has historically been designed with men in mind. Women were not admitted into the astronaut program until 1978, and an American woman did not fly into space until Sally Ride did so in 1983. (Two Soviet women preceded her.) On Oct. 11, 1984, Kathryn D. Sullivan became the first American woman to perform a spacewalk.
Ms. McClain returned to Earth in June after 204 days in space, including two spacewalks with male colleagues totaling 13 hours and 8 minutes. (Ms. McClain’s domestic troubles also made headlines this summer, after she was accused of gaining access to her estranged wife’s bank account from space. She denies any wrongdoing.)
This is the current lineup
Ms. Meir and Ms. Koch, the astronauts on Friday’s spacewalk, were both part of NASA’s 2013 class of astronaut trainees. The eight-member class was the first to include equal numbers of men and women. (Mr. Hague and Ms. McClain were also part of that class.)
Ms. Meir grew up in Caribou, Me., according to her official NASA biography. She holds a master’s degree from the International Space University, near Strasbourg, France, and a doctorate in marine biology from the Scripps Institution of Oceanography in San Diego. She has researched human physiology for Lockheed Martin and worked as an aquanaut in an underwater habitat, among other posts.
Ms. Meir arrived at the International Space Station at the end of September, and posted photos of joyful hugs as she greeted her colleagues. Friday’s spacewalk was her first.
Ms. Koch, a Michigan native, grew up in Jacksonville, N.C., and most recently lived in Livingston, Mont., according to her official biography. She holds a master’s degree in electrical engineering from North Carolina State University. Before becoming an astronaut, she worked in space science instrument development and remote scientific field engineering for NASA and the United States Antarctic Program, among other institutions.
She is on track to break the record for the longest single spaceflight by a woman, with an expected 328 days in space if she returns to Earth in February, as scheduled. Friday’s outing was to be her fourth spacewalk.
In an interview with NASA TV this month, Ms. Koch was asked if she was bothered that her accomplishments were often talked about in terms of her gender, or whether she believed it was important to mark milestones.
“That is something I’ve done a lot of thinking and reflecting on,” she said. “And in the end, I do think it’s important. And I think it’s important because of the historical nature of what we’re doing and that in the past women haven’t always been at the table.”
Ms. Koch said that it was “wonderful” to be a part of the space program at a time “when all contributions are being accepted, when everyone has a role, and that can lead in turn to an increased chance for success.” She added that “it’s an important aspect of the story to tell” because many people derive motivation from inspiring stories of people who look like them.
Ms. Meir sounded a similar note and credited the work of women who came before them. (She was scheduled to be the 15th woman to do a spacewalk, and all but one of her predecessors was American.)
“We don’t really even think about it on a daily basis,” she said of gender. “It’s just normal. We’re part of the team.”
So what size suits are they wearing?
Spacesuits are essentially mini-spaceships, built for one of the most dangerous tasks during an astronaut’s mission. There are six aboard the International Space Station, and they are individually configured for each astronaut, taking into account more than 80 different body measurements, Stephanie Schierholz, a NASA spokeswoman, said in an email.
“The suit has three sizes of upper torso, eight sizes of adjustable elbows, over 65 sizes of gloves, two sizes of adjustable waists, five sizes of adjustable knees and a vast array of padding options for almost every part of the body,” she wrote.
Both women had medium-size torso components for Friday’s spacewalk, and the two male spacewalkers aboard the station also use that size, Ms. Schierholz said.
The suits were originally designed more than 40 years ago. But NASA is developing new ones as part of its Artemis program, which aims to put the first woman and the next man on the moon by 2024 — and then send astronauts to Mars.
NASA officials unveiled two new spacesuit prototypes at the agency’s headquarters in Washington on Tuesday. The new suits feature advanced communications capabilities and protect astronauts from the extreme environment of space while allowing them to move with greater ease.
Jacey Fortin contributed reporting.