The International Space Station's Twitter account tweeted Tuesday evening that the spacewalk will take place "no earlier than Friday", updating NASA's earlier announcement that it would happen either Thursday or Friday morning.
That changes Friday with spacewalk No. 421.
SEE ALSO: NASA Astronaut's Space Selfie On The International Space Station Is Literally 'Out Of This World!' But according to Space.com, only 15 women have participated in spacewalks, and all were accompanied by men.
The space agency has, however, pushed the event back by one day to Friday, October 18. Eastern. The spacewalk is scheduled to begin at about 7:50 a.m.
NASA astronauts Christina Koch and Jessica Meir will make "HERstory", as NASA is calling it, with the first all-female spacewalk.
They will be replacing a faulty battery charge/discharge unit that failed to activate after a spacewalk October 11.
It seems that the all-female spacewalk, while notable, isn't an event that NASA was trying to consciously facilitate.
Simply hit the play button on the embedded video player above. Three battery replacement spacewalks will be rescheduled, and five spacewalks to fix a cosmic particle detector remain on the calendar for November and December.
"The device regulates the charge to batteries that collect and distribute power to the station".
The battery charger failed after Koch and a male crewmate installed new batteries outside the station last week.
The spacewalk was originally planned for March but was cancelled due to a lack of spacesuits. Koch's answer, which was deemed "perfect" by Meir, is quoted here in full: "I$3 n 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". Both Koch and Meir are current residents aboard the ISS, with the former set to achieve a new record for longest-ever single continuous stay in space for a woman when she returns to Earth in February 2020.