Astronauts complete second spacewalk preparing for ISS solar panel upgrades

A pair of astronauts aboard the ISS completed a difficult installation of struts that will hold new solar panel arrays on the outside of the ISS. The second spacewalk was conducted on March 5 and was required after the first spacewalk for the procedure didn't go as planned. Astronauts Kate Rubins from NASA and Soichi Noguchi from JAXA spent six hours and 56 minutes working in space.The pair spent most of their time far away from the core of the ISS. The work took them to a location on the station's Portside to upgrade the 4B and 2B solar panels. Those panels have been installed on the ISS since 2007, when they were delivered by space shuttle mission STS-97. Additional panels are being added to the space station because the original panels have degraded.

The eventual goal is to add a new set of solar panels on top of the station's current arrays to boost power levels by 20 to 30 percent. The new solar panels will be shipped to the ISS in a future SpaceX Dragon cargo mission. However, before those panels can be delivered, the first step was to install the struts on the exterior of the space station.

The spacewalk was challenging, requiring the astronauts to move hand over hand along the station's P6 structure. They had to carefully thread their tethers through components of the station to avoid becoming tangled. Rubins and NASA astronaut Victor Glover conducted the first spacewalk that didn't go as planned.

One bit of challenge on the mission came when Rubins struggled to bolt the previously assembled "upper triangle" struts into place. One of the four bolts didn't move smoothly, causing issues. Eventually, mission control decided that only three bolts were enough to hold the strut in place.