Cape Canaveral: Two astronauts ventured outside the International Space Station on Friday on the first of three outings to prepare the orbiting research laboratory for commercial space taxis and to tackle maintenance chores.

US station commander Shane Kimbrough, 49, and French flight engineer Thomas Pesquet, 39, floated outside the station's airlock 402 kilometres above Earth.

French astronaut Thomas Pesquet takes a selfie during his last spacewalk in January. Credit:Thomas Pesquet

The astronauts worked to reconfigure the $US100 billion station, operated by 15 nations, and add docking ports for new spaceships in development by Boeing and Space Exploration Technologies (SpaceX).

Kimbrough, making his fifth spacewalk, headed to the station's central beam to upgrade a computer relay box before turning his attention to a docking system that will be used by future fleets of commercial space taxis.