Canadian astronaut Joshua Kutryk and NASA astronaut Anil Menon left the International Space Station’s airlock Thursday morning to work on its starboard truss. Their assignment is to install and deploy the eighth roll-out solar array, on the station’s 3B power channel.

The excursion follows the pair’s October 29 installation of the seventh array on the 2A channel. NASA described Thursday’s work as the final planned installation in the power upgrade. Its initial report confirms the spacewalk started; it does not yet confirm that the new array is deployed.

NASA estimates the completed upgrade will bring generating capacity from 160 kilowatts to about 215 kilowatts. Extra power supports station operations and will also help meet requirements for the station’s eventual controlled deorbit.

Thursday’s excursion is Kutryk’s second and Menon’s fifth. The work is part of Expedition 75, and NASA is tracking progress through its station mission updates.