Spacewalkers Step Out On Special Delivery

Spacewalking astronauts are setting out to help deliver the last addition the U.S. side of the International Space Station, an annex that includes an Italian-built observation deck that will provide unparalleled views of the outpost and Earth.

Endeavour mission specialists Bob Behnken and Nicholas Patrick switched their spacesuits to battery power at 9:17 p.m. as the joined shuttle-station complex soared 210 miles over the southern tip of South America. The move marked the beginning of the planned 6.5-hour excursion.

Behnken exited the station's U.S. Quest airlock around 9:30 p.m.

"Have a great day outdoors," said mission specialist Steve Robinson, who is directing the spacewalk from inside the joined shuttle-station complex. "We're just going over Rio De Janeiro."

Click the NASA TV box on the right side of the page to launch our NASA TV viewer and live coverage of the spacewalk. The spacewalk is the 138th to be conducted in the assembly and maintenance of the station, the first two building blocks of which were linked in low Earth orbit in late 1998.

The prime goal: Install the U.S. Tranquility module on the port side of the U.S. Unity module. Tranquility features the Italian-built Cupola, an extension that sports seven windows and affords a 360-degree view.

Patrick will disconnect power cables that electrically link the Tranquility module to the orbiter Endeavour. Behnken will remove eight protective blankets from the module's berthing mechanism so it can be linked to the Unity module.

Working inside the U.S. Destiny laboratory, shuttle pilot Terry Virts and mission specialist Kay Hire will lift the 15-ton module out of Endeavour's cargo bay and then put it in place on the left side of Unity.

Behnken is wearing the spacesuit with solid red stripes and is answering to the radio call sign "EV-1." Patrick is wearing an all-white suit and is "EV-2."

Mission specialist Steve Robinson is directing the spacewalk from inside the shuttle-station complex, which weighs in excess of 1 million pounds.

The timing of the spacewalk is laid out in this latest revision -- Rev D -- of the STS-130 NASA TV Schedule.

Check out the crew's detailed timeline here in the Flight Day 5 Execute Package.