STORY WRITTEN FOR CBS NEWS & USED WITH PERMISSION
Two astronauts worked outside the International Space Station Wednesday to help reposition two spare solar array ammonia coolant pump assemblies, putting a failed unit, dubbed “Leaky,” into long-term storage and attaching another, known as “Frosty,” to an appendage of the lab’s robot arm.
After the spacewalk is over, arm operators at the Johnson Space Center in Houston planned to move Frosty to the P6 solar array segment at the far left end of the station’s power truss where it can be plugged in for diagnostics. It will join yet another spare pump flow control sub-assembly, or PFCS, known as “Motley,” that is already in place on P6.
The units are designed to help push coolant through solar array batteries to keep them from overheating. The appropriately named Frosty has been stored outside the station for nearly 20 years but it once was without heater power for an extended period and engineers are not sure if it’s still a viable spare.
Motley was delivered to the lab complex by a SpaceX Dragon cargo ship earlier this year. As its name might suggest, it is made up of spare parts but it is ...