The first-ever all-female spacewalk is underway. You can watch footage in the video player, above
Christina Koch and Jessica Weir will be the two US astronauts making history when they venture out of the International Space Station (ISS) together to replace a power controller that failed during the weekend. Their spacewalk is expected to take about five and a half hours.
Koch and another US astronaut, Anne McClain, were initially scheduled to make the first all-female spacewalk back in March. But the event had to be postponed because NASA did not have the two medium-sized suits needed onboard the ISS.
McClain has since returned to earth while Weir made it to the ISS in September. NASA has now sent up another medium-sized suit.
The first woman to make it into space was Russia's Valentina Tereshkova in 1963. It took another 21 years for a woman to take part in a spacewalk.
The US space agency also announced on Wednesday that it aimed to send the first woman and the next man to the moon in 2024 and unveiled the suits they will be wearing for the mission.