Two astronauts are back aboard the International Space Station after a spacewalk to conduct experiments and maintenance.

Station Commander Leroy Chiao of the United States and Russian flight engineer Salizhan Sharipov spent a total of five hours, 28 minutes outside the orbiting station Wednesday.

The U.S. space agency says the crew members installed a work platform, set up two experiments, and checked vents on systems that help control the station's atmosphere.

The spacewalk was the first for the current two-man crew, who arrived at the station in October. NASA says the crew members plan to conduct their second spacewalk in March.