HISTORY WRITTEN FOR CBS NEWS AND USED WITH PERMISSION
Picking up where they left off last week, two space station astronauts ventured out of the outpost on Wednesday and completed replacing old batteries in one of the lab’s eight electrical power channels. A final power circuit will be equipped with fresh batteries for two more spacewalks later this month, concluding a complex, multi-year upgrade.
The battery work on Wednesday was completed in no time, and the astronauts were able to get on with some lower priority “priority” tasks. The only one that was not accomplished was the planned removal of a groundhandling device in one of the boats that anchored a set of solar panels.
After unscrewing the fitting, Robert Behnken was unable to release it, despite using a lever bar and a bit of grease on his elbow. Flight controllers finally told him to close it again, postponing the move to a future spacewalk. NASA plans to remove various accessories that are no longer needed to clear the way for a planned upgrade of the power system later.
Otherwise, the six-minute and one-minute spacewalk went smoothly, and engineers reported that the newly installed batteries were operating normally.
Floating in the Quest Lock, Behnken and station commander Chris Cassidy switched their battery-powered space suits at 7:13 am to begin their second spacewalk in five days, the 229th in the station’s history and the eighth overall. for both astronauts.
After checking the safety ties and picking up their tools, the astronauts floated outside and made their way to the far right of the space station’s power armor to continue the battery replacement work.
The space station is equipped with four huge wings of solar panels, each of which feeds electricity into two power circuits or channels. Each of the eight power channels originally included six nickel-hydrogen batteries, 48 in total, to provide electricity when the station is in orbital darkness.
But the original batteries are running low, and NASA is in the process of replacing the 48 with 24 more powerful lithium-ion power packs and adapter plates that complete the circuit to replace the batteries that were removed but not replaced.
During spacewalks in 2017, 2019, and January of this year, 36 old batteries were replaced in three of the four sets of solar panels. Cassidy and Behnken are working to replace a final set in the station’s external external arrangements.
Last Friday, they removed five of the six nickel-hydrogen batteries in one of the external power channels and installed two of the three lithium-ion batteries and two of the three adapter plates in their place.
During Wednesday’s work, they finished updating Power Channel 1B and loosened the bolts securing the batteries in Power Channel 3B to save time during the first of two spacewalks later this month to finish the replacement job. battery.
Before calling him a day, they routed the power and data cables to a new wireless communication system and attempted to remove the tamper. Engineers will solve that problem to find a solution for a downstream spacewalk.
