Article Posted on : - Mar 01, 2011

Mission Specialists Steve Bowen and Alvin Drew work outside the International Space Station during the first spacewalk of STS-133. Photo: NASA TV.

WASHINGTON (AFP): Two US astronauts conducted the first of two spacewalks for space shuttle Discovery' STS-133 mission on Monday, NASA said.

The walk which began at 9:46 am Eastern time (1546 GMT), was conducted in order to install a permanent module onto the orbiting lab.

Spacewalkers Steve Bowen and Alvin Drew arrived at the ISS aboard the space shuttle Discovery, which launched Thursday on its final mission before becoming the first of three spacecraft to retire this year as the American shuttle program ends.

The Discovery crew is there to deliver the Permanent Multipurpose Module, with extra storage space and an area for experiments, and the Express Logistic Carrier, an external platform for large equipment.

"The first spacewalk's objectives will be to install an extension cable, a pump module vent tool, a camera wedge and extensions to the mobile transporter rail," NASA said.

The extension cable is being installed as preparation for the setup of the Italian-built Leonardo module as a permanent fixture at the lab.

Then the astronauts will start work on "moving a failed pump module to a more permanent storage location on the space station," NASA said.

The spacewalk will wrap up about six hours after it began, with the Japanese "Message in a Bottle" experiment, in which they "expose a metal canister to capture the vacuum of space," NASA said. The spacewalk is to end at 2048 GMT.