Astronaut Bob Behnken conducts a spacewalk

iss063e034131 (July 1, 2020) — NASA astronaut and Expedition 63 Flight Engineer Bob Behnken (upper left) works during a six-hour and one-minute spacewalk to swap an aging nickel-hydrogen battery for a new lithium-ion battery on the International Space Station’s Starboard-6 truss structure. Protruding horizontally from the truss are the Thermal Control System radiators that dispel heat generated by the orbiting lab’s power systems.