The International Space Station’s outdated nickel-hydrogen batteries are being replaced with lithium-ion units.
Spacewalking astronauts have hustled through battery hook-ups outside the International Space Station in a major upgrade of the solar power grid.
Off to a quick and early start, Nasa’s Christina Koch and Nick Hague attached the circuitry for the stronger new batteries, continuing replacement work that began a week ago.
Spacewalkers @AstroHague and @Astro_Christina continue transferring hardware from the @JAXA_en HTV-7 pallet to the Port-4 truss structure. #AskNASA | https://t.co/yuOTrZ4Jut pic.twitter.com/CnQ1pTVYvC
— Intl. Space Station (@Space_Station) March 29, 2019
It was not the team Nasa envisioned – Ms Koch was supposed to go out with fellow astronaut Anne McClain for the first all-female spacewalk, but the line-up was changed because two medium-sized suits were not readily available for the women.
After Nasa was criticised over the switch, Ms McClain said the decision was based on her recommendation.
“Safety of the crew and execution of the mission come first,” the army aviator said on Twitter.
This decision was based on my recommendation. Leaders must make tough calls, and I am fortunate to work with a team who trusts my judgement. We must never accept a risk that can instead be mitigated. Safety of the crew and execution of the mission come first. https://t.co/VU9QNaHHlK
— Anne McClain (@AstroAnnimal) March 27, 2019
Mr Koch — the 14th woman to conduct a spacewalk — arrived at the space station two weeks ago with Mr Hague. Ms McClain, who last week became the 13th female spacewalker, has been on board since December. More than 200 men have walked in space.
The space station’s outdated nickel-hydrogen batteries are being replaced with lithium-ion units, a lengthy process spanning years.
These batteries store power collected by the solar wings and keep the outpost running when it is on the night side of Earth.
Besides connecting three fresh batteries, Ms Koch and Mr Hague needed to disconnect one of the three installed last week because of higher voltage than expected. It will be replaced by two old-style batteries until a spare arrives.
We’ve heard the disappointment from many about the change in astronaut assignments for this Friday’s spacewalk and the many questions about how the size of a spacesuit affected the decision. So what’s the deal? Here are answers to some frequent questions: https://t.co/tNn1DKfUD1 pic.twitter.com/pl9TPnVF28
— NASA (@NASA) March 27, 2019
Ms McClain pulled out of Friday’s spacewalk when she realised the medium suit she used last week fit her best. It had planned that she would switch to a large. Ms Koch also takes a medium.
While another medium-sized spacesuit top is available, it would have taken 12 hours to get it ready — time Nasa did not want to spend given all the other station activity.
“It’s safer & faster to change spacewalker assignments than reconfigure spacesuits,” Nasa said on Twitter.
All first-time space fliers, Ms McClain, Ms Koch and Mr Hague are members of Nasa’s astronaut class of 2013, the first to include equal numbers of women and men.
A third spacewalk is planned for April 8. Ms McClain will go out with Canadian David Saint-Jacques.
The 250-mile-high station is also home to two Russians.