SAN DIEGO -- UC San Diego alumna Jessica Meir participated in NASA's first all-female spacewalk Friday to replace a faulty power unit outside the International Space Station.
Meir and Christina Koch replaced a battery charge/discharge unit that failed to activate after new lithium-ion batteries were installed on the space station's exterior structure on Oct. 11, according to NASA.
Meir was extravehicular crew member 2 wearing the suit with no stripes. Koch was extravehicular crew member 1 wearing the spacesuit with the red stripes.
Meir is the 15th woman to walk in space and 14th American woman. This was the 43rd spacewalk to include at least one woman, according to NASA.
Cmdr. Luca Parmitano of the European Space Agency and NASA flight engineer Andrew Morgan assisted the spacewalkers. Parmitano controlled the Canadarm2 robotics arm and Morgan provided airlock and spacesuit support.
During the walk, President Donald Trump, Vice President Mike Pence, presidential adviser Ivanka Trump and NASA Administrator Jim Bridenstine called Meir and Koch to congratulate them on their historic accomplishment.
"Today's historic effort continues to lay the foundation for our Artemis program, when the first woman and next man walk on the surface of the moon in preparation for the next giant leap -- sending astronauts to Mars," Bridenstine said.
The spacewalk was livestreamed on NASA's website at nasa.gov/nasalive just before 4 a.m. PDT.
Meir flew to space aboard the Russian Soyuz MS-15 spacecraft late last month for the first time and is expected to spend roughly six months aboard the ISS to conduct research. She is expected to make a second spacewalk later this month.
Meir earned a doctorate from the Scripps Institution of Oceanography in 2009 and was selected as an astronaut in 2013.
Koch and Meir spoke about women working in human spaceflight during a recent news conference.
"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," Koch said. "It's wonderful to be contributing to human spaceflight at a time when all contributions are being accepted, when everyone has a role and that can lead, in turn, to increased chance for success.
"There are a lot of people that derive motivation from inspiring stories from people that look like them and I think it's an important aspect of the story to tell," Koch said.
"What we're doing now shows all the work that went in for the decades prior, all of the women that worked to get us where we are today," Meir added. "I think the nice thing for us is 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."
Fellow NASA astronaut Drew Morgan, also currently on the station, tweeted in support of Koch and Meir during the walk.
"So proud of my astrosisters @Astro_Christina and @Astro_Jessica! We've been training together since our selection in 2013, and now they're out on a history-making spacewalk! #AllWomanSpacewalk"