CAPE CANAVERAL, Feb 20: Two US astronauts floated outside the International Space Station on Wednesday in the first US spacewalk from the orbiting outpost without a space shuttle docked there.

Astronauts Carl Walz and Dan Bursch worked fast and trimmed nearly an hour off what was to be a 6-1/2 hour exercise in attaching cables, moving tools and photographing dents and dings on the station’s outer surface.

None of the tasks was critical, said NASA, the US space agency. The real goal was to see how US equipment, systems and procedures worked before committing station astronauts to more critical operations.

Bursch and Walz had mostly trained for this job using virtual reality computer programs while living on the station the past 10 weeks.

By contrast, shuttle astronauts get hands-on training in a huge water tank where they float much like they would in space, and their training last for months or even years, lasting until just days before launch.

“This is a crew that hasn’t been in the natural buoyancy laboratory for months,” said space-station flight director Sally Davis. But she said the station crew was better adapted to working in space than a shuttle crew having left Earth’s gravity just days before.

Although this was the first spacewalk run by NASA’s Mission Control, both Walz and Bursch have made separate spacewalks with the station’s Russian commander, Yuri Onufrienko.

RUSSIAN SPACEWALKS: Those were considered Russian spacewalks, with the astronauts wearing Russian spacesuits and exiting the Russian segment of the station from a Russian air lock.