Correction, June 14, 2018: This post has been updated to clarify the timing of the first uncrewed test missions, which are planned for later this year.

NASA astronauts Ricky Arnold and Drew Feustel are set to go on their third spacewalk together this year on Thursday at the International Space Station. Their new Expedition 56 crewmates Serena Auñón-Chancellor and Alexander Gerst are training today to support the two spacewalkers.

Arnold and Feustel will begin Thursday’s spacewalk at 8:10 a.m. to install new high definition cameras to support upcoming commercial crew missions from SpaceX and Boeing to the orbital laboratory. The first uncrewed test missions are planned to begin later this year. The cameras will provide improved views of the commercial crew vehicles as they approach and dock to the station. NASA TV will provide complete live coverage of the 211th space station spacewalk starting at 6:30 a.m.

Auñón-Chancellor and Gerst, who just arrived at the station on Friday, will assist the spacewalkers on Thursday. Gerst will help the spacewalkers in and out of their spacesuits. Auñón-Chancellor will operate the Canadarm2 robotic arm. The duo practiced today on a computer the robotics procedures necessary to maneuver a spacewalker to and from the worksite on the starboard side of the station’s truss structure.

Arnold and Feustel had some extra time today to work on science and maintenance activities. Arnold worked with the Microgravity Science Glovebox to troubleshoot a semiconductor crystal growth experiment. Feustel performed some plumbing work in the Tranquility module before relocating a pair of incubator units to support new experiments being delivered on the next SpaceX Dragon cargo mission. Finally, the duo readied the Quest airlock and their spacesuits for Thursday morning’s spacewalk.