The first spacewalk in 2020 is also the second in history to be conducted by an all-female crew.
The walk, which will see astronauts Jessica Meir and Christina Koch replace batteries on solar arrays on the International Space Station, started on Wednesday morning and is being broadcast worldwide by NASA.
An all-female spacewalk
Meir and Koch already made history in October of last year when they carried out the very first all-female spacewalk. An all-female spacewalk planned for before October of last year had to be canceled due to a lack of spacesuits.
The two astronauts are replacing nickel-hydrogen batteries with new lithium-ion batteries that are able to store power generated by the solar arrays on the ISS's port truss, NASA reports.
The spacewalk is underway at the time of writing. Live coverage started at 5:30 a.m. EST on NASA Television and the agency’s website.
The batteries were sent up to the station in September aboard the Japanese H-II Transfer Vehicle.
Only part of the operation is being carried out today. The batteries will be fully installed after a second spacewalk scheduled for Monday.
As CNN reports, today's spacewalk will be the second spacewalk for Meir and the fifth for Koch.
The 225th spacewalk conducted at the ISS
Meir and Koch are now part of NASA's rich history, with NASA saying that Wednesday's spacewalk is the 225th to have been conducted at the International Space Station.
All of this is part of the overall upgrade of the ISS's power system that began with a similar battery replacement carried out during spacewalks in January 2017.
If the battery replacement goes smoothly, NASA astronaut Andrew Morgan and space station Commander Luca Parmitano from the European Space Agency will carry out their own spacewalk on January 25.
They will finish installing the Alpha Magnetic Spectrometer's (AMS) new cooling apparatus, a system that is designed to search for dark matter and antimatter in the universe.