Two astronauts stepped out of the International Space Station to begin the first spacewalk of the Shuttle Discovery's mission to the orbiting outpost.
National Aeronautics and Space Administration astronauts Scott Parazynski and Doug Wheelock opened the station's hatch at 5:02 a.m. Houston time as they passed over Chile. Parazynski entered the frigid vacuum of space, followed by Wheelock, footage aired live by NASA's online television station showed. The sortie is the first of five planned in eight days, a record for a shuttle mission.
During the outing, the men will remove a broken antenna for return to Earth and begin preparations for the installation of Harmony, an Italian-built module that will increase the living and working space in the orbiting outpost by more than 2,600 cubic feet (78 cubic meters) and provide docks for Japanese and European laboratories, NASA said in an e-mailed statement.
Parazynski and Wheelock docked yesterday at the space station aboard Discovery, which lifted off on Oct. 23. Discovery's seven astronauts joined three crewmembers aboard the space station.
The two spacewalkers spent the night in an airlock to purge their bodies of nitrogen. Their outing today, scheduled to last 6 1/2 hours, is being coordinated by European Space Agency astronaut Paolo Nespoli, of Italy. They'll move the Harmony module from the shuttle into a temporary position. The unit won't be installed in its permanent location until after Discovery departs on Nov. 4.
``Harmony is the first addition to the station's pressurized volume since the arrival of the Russian Pirs docking compartment in 2001,'' the European Space Agency said today in a statement on its Web site. ``The installation of Harmony paves the way for the addition of the European Columbus laboratory in December 2007, and the Japanese Kibo laboratory in April next year.''
During the remaining four spacewalks, the combined crew of the shuttle and space station will carry out electrical work, test repair techniques on Discovery's heat shields, and further prepare Harmony for installation.