Two astronauts made history Friday morning as the first women to participate in an all-female spacewalk. Christina Koch and Jessica Meir ventured outside the International Space Station at about 7:50 a.m. to make an urgent repair to its power system.

Historic NASA's First All-Female Asronauts Complete The Spacewalk 1


Originally, NASA had planned an all-female spacewalk in March. But that event — which was to have involved Koch and NASA astronaut Anne McClain — was scrapped because there weren’t enough spacesuits of the right size available on the station. NASA was criticized for not having enough uniforms for two women to participate in a spacewalk together.

NASA is hosted a live stream on their site, and celebrating “the first #AllWomanSpacewalk in human history!” (#AllWomanSpacewalk is trending on Twitter.)

President Donald Trump called the two astronauts on Oct. 18 while they participated in NASA’s first all-female spacewalk. Trump congratulated Christina Koch and Jessica Meir on their achievement. “You’re both brave, brilliant women, and you represent this country so well,” Trump said.