Astronaut Robert Curbeam spent over 6 hours in space working on the space station (Image: NASA)
Two astronauts from the space shuttle Discovery have successfully attached a huge truss to the International Space Station. The spacewalk was the first of three designed to extend and rewire the orbital outpost.
US astronaut Robert Curbeam and Sweden’s first astronaut, Christer Fuglesang, spent 6 hours and 36 minutes in space installing the two-tonne truss segment to the ISS, among other tasks.
“Christer, you knocked yourself out,” mission control told Fuglesang. “From here on the ground, we’d like to send our congratulations for a 100% successful first [spacewalk],” said astronaut Steve Robinson, speaking from mission control.
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The spacewalk ended at 0307 GMT on Wednesday as the station passed over north Africa. The operation was particularly sensitive because the astronauts had to move the truss within centimetres of the fragile solar arrays that provide electricity to the station.
In a delicate manoeuvre, the 3.37-metre (11-foot) truss was guided by the ISS robotic arm, operated by US astronaut Joan Higginbotham. She coordinated the movements with Curbeam and Fuglesang, who bolted the structure in place.
The spacewalking pair also hooked up six cables on the space station for electricity, communications and climate control. Last on their worksheet were operations to allow enough room for new solar arrays to track the Sun’s rays in a 360° rotation.
Double power
The ISS structure is being assembled piece by piece. Construction resumed in September with the Atlantis mission, after a three-year hiatus following the 2003 Columbia disaster.
Two other spacewalks, scheduled for Thursday and Saturday, are expected to be highly complex (see ). The astronauts are tasked with rewiring the electricity and climate control of the US-made portion of the ISS from its present, temporary set-up.
The work, during which power to half of the ISS will be switched off, includes activating the solar arrays installed by the Atlantis mission, doubling the station’s present electrical output.
The current Discovery mission is one of 14 shuttle flights NASA has planned over the next four years to complete construction of the ISS by 2010, when the shuttle fleet is to be retired.
All clear
Discovery blasted off on its 12-day mission late on Saturday from Cape Canaveral, Florida, in the first night launch in four years (see Rocket’s red glare to illuminate night launch).
NASA engineers say Discovery’s heat shield has not suffered any damage. Two preliminary inspections carried out after takeoff and shortly before Discovery docked with the ISS showed no cause for concern. Such inspections on the shuttles have become routine since the Columbia tragedy.
Columbia’s heat shield was pierced by foam insulation that peeled off its fuel tank during lift-off, causing the shuttle to disintegrate during its return to Earth on 1 February, 2003, killing all seven astronauts on board.
The Return of the Space Shuttle – Learn more in our continuously updated .
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