Spacewalk veterans take a trip outside the ISS to pump up the power with new solar arrays

Lego ISS fans, look away now

International Space Station (ISS) astronauts are venturing out of the orbiting outpost today to replace its ageing solar arrays.

It is an international effort, with NASA's Shane Kimbrough and ESA's Thomas Pesquet exiting the lab's Quest airlock to deploy the first of six arrays (dubbed ISS Roll-Out Solar Arrays – iROSAs) that should boost the power supply of the station and keep things ticking over until decommissioning time.

Two of the new arrays arrived in SpaceX's latest Dragon cargo spacecraft and were plucked from the freighter's trunk by the ISS's robotic arm. Kimbrough and Pesquet will work first on the far end of the left (port) side of the station's truss to install the first array and venture out once more on Sunday 20 June to install the second.

The ISS currently has eight solar panels, which, while they are still generating power, are degrading with age. The first pair have been in use since 2000, quite some way beyond the original 15-year lifespan. The six new arrays will be placed in front of the old ones (rather than replacing them) and it is expected that the ISS's total power will increase to 215 kilowatts from the current 160 kilowatts once the work is complete.

The same solar array design is planned for use on the Lunar Gateway.

The duo are spacewalk veterans, having previously left the interior of the ISS to upgrade the station's batteries, lubricate the Canadarm2 and prep the space-facing docking port on Node 2 for the docking adaptor to which the SpaceX cargo Dragon is docked.

Kimbrough and Pesquet arrived at the ISS on board Crew Dragon Endeavour as part of the Crew-2 mission. Crew-2 pilot Megan McArthur will be tasked with manoeuvring arrays into place with the Canadarm2 while NASA astronaut Mark Vande Hei (who was brought to the ISS on Soyuz MS-18) serves as backup. ®