Washington, Feb 28 (DPA) Two space shuttle Discovery astronauts left the International Space Station Monday for the first spacewalk of their 11-day mission.
Steve Bowen and Alvin Drew will move a failed ammonia cooling pump removed on an earlier mission and install a power extension cable and camera equipment.
The planned six-and-a-half-hour spacewalk got underway at 1618 GMT.
The Discovery is on its final mission before retirement as NASA works to mothball the shuttle fleet this year. Two more flights are set for later this year of the shuttle Endeavour and Atlantis.
The mission is delivering the last major US contribution to the ISS – an extra room – along with supplies and equipment, including a human-like robot, known as Robonaut 2 (R2), the first such robot ever sent to space.