Astronauts Peggy Whitson (L) and Shane Kimbrough (R) prepare to leave the airlock. There have been 196 spacewalks in support of the International Space Station so far.
On Friday, January 6th, astronauts from Expedition 50 of the ISS exited the Quest Airlock for a six and a half hour EVA to begin the four-year process of changing out the station's main batteries, which are reaching their serviceability lifespan. The new Li-Ion batteries were brought to the station on the Japanese HTV-6 cargo spacecraft on the external pallet. Using the stations remote-control arm, the batteries were removed from the craft and placed in the are of the exchange, which for this mission was the S4 segment of the main truss. There was a lot of work to do in preparation for this part of the battery exchange, both inside and out of the station. Relays and cables to affected station segments were checked, secured, and switched to other areas for the duration of the exchange.
Shane Kimbrough looks quite pleased to be performing his 3rd career spacewalk. Station solar panels in the background.
During the last week, ground controllers used one of the access arms to begin a series of shuffling old batteries from their home on the truss and replacing them with the new batteries stored in temporary positions on the truss. The purpose of this EVA was to finish certain installation tasks that could not be done with the robotic arms. It proves again how the human presence can never be completely removed from space activities for maximum efficiency.
Astronaut Shane apparently enjoys selfies. Up there, who wouldn't?
Peggy Whitson during suit preparation. This was her 7th career EVA.
The EVA concluded with successful connections of three of the six replaced batteries. Part two of this EVA is scheduled for Friday January 13th, when Kimbrough goes outside again, this time with ESA astronaut Thomas Pesquet, to complete the hookups for the remaining three batteries. The new lithium-ion batteries are a great improvement over the older nickel-hydrogen batteries. The old batteries will be moved by the robotic arm onto the storage pallet on the HTV-6. They will burn up when the HTV-6 is plunged into the atmosphere over the Pacific for disposal.
For a very detailed description of the EVA, go to: NASASpaceflight.com: https://www.nasaspaceflight.com/2017/01/spacewalkers-upgrading-iss-batteries/