Outside the International Space Station, Expedition 50 Commander Shane Kimbrough of NASA and Flight Engineer Thomas Pesquet of the European Space Agency conducted a spacewalk in U.S. spacesuits to upgrade the system for the 1A power channel of the orbital laboratory’s starboard 4 (S4) truss solar arrays. Moving adapter plates and batteries, Kimbrough completed the work to hook up electrical connections for the last three of six new lithium-ion batteries recently delivered to the station, and to move the last of the old nickel-hydrogen batteries that will be stored on the station. It was the second spacewalk in a week for Kimbrough and the fourth of his career, and the first for Pesquet in the refurbishment of two of the station’s eight power channels. On Jan. 6, Kimbrough and Flight Engineer Peggy Whitson of NASA conducted similar work for the 3A power channel of the station’s S4 solar arrays.