The crew was first in the airlock donning their suits ahead of their endeavor. During the spacewalk, Glover and Hopkins are tasked with working on the station's port truss -- or "backbone" -- where they will vent early ammonia system jumper lines and relocate one of them near the Quest airlock in order to reconnect the jumper cable to the station's cooling system and increase its efficiency. Next, the astronauts will replace a wireless antenna assembly on the Unity connecting module, a component that links the Russian and U.S. segments of the station, and install a "stiffener" on the airlock's thermal cover and route cables to provide ethernet capabilities for two high-definition cameras on the port truss.