NASA Astronauts Perform Maintenance Duties Outside Space Station
It was the fifth ISS spacewalk of 2018 and the 210th spacewalk since December 1998.
The two astronauts were swapping out cooling components on the exterior of the ISS. According to NASA, they moved the pump flow control subassembly (PFCS), which pumps liquid ammonia and provides temperature control by regulating the flow. This drives and controls the flow of ammonia through the external loops of the station’s cooling system.
NASA said they also replaced a camera group and a degraded Space to Ground Transmitter Receiver Controller.
The astronauts are part of Expedition 55 that launched in March.