NASA astronauts Anne McClain and Nichole Ayers emerged around 9 a.m. Thursday, May 1 for the fifth-ever all-female spacewalk.

McClain, an Army colonel and helicopter pilot, should have taken part in the first all-female spacewalk in 2019, but there weren’t enough medium-size suits. The first women-only spacewalk was by Christina Koch and Jessica Meir. The latest was the fifth all-female spacewalk in 60 years of spacewalking.

Two NASA astronauts have completed a nearly six hour long spacewalk to maintenance and upgrades on the International Space Station, the agency announced.