Two Endeavour astronauts completed a seven-hour, 24-minute spacewalk at 7:39 am (1139 GMT) Friday, which was the last-ever conducted by a space shuttle crew, according to dpa. Astronauts Mike Fincke and Greg Chamitoff, who left the International Space Station (ISS) at 0415 GMT, transferred a part from the shuttle to the station so it could continue to be used after the shuttle is retired. The orbital boom sensor system has been used on the shuttle as an extension of its robotic arm to survey the craft for damage sustained during blast-off. It is now available to extend the reach of the space station's robotic arm. This was Fincke's ninth spacewalk, and Chamitoff's second. At about 8 pm, Fincke will become the US astronaut who has spent the most number of days in space, surpassing Peggy Whitson's record of 377 days, NASA said. The spacewalk was the fourth and final of the Endeavour's mission and is designed to leave the space station in top shape before the shuttle is retired. Endeavour blasted off May 16 on a 16-day mission. One more shuttle flight is planned - Atlantis is to fly to the station in July. But no spacewalks are scheduled for that mission. Astronauts living full time on the station also conduct spacewalks independently of visiting shuttles. The shuttle is the only craft large enough to bring bulky cargo such as major parts to the station, although Russian, European and Japanese vehicles can bring smaller payloads. The shuttle fleet is being retired after 30 history-making years as the US space agency focuses its efforts on developing a long-range vehicle for travel to Mars and other distant destinations. On Tuesday, NASA unveiled its plans for the development of the long-distance spacecraft it hopes to use to travel to deep space. The National Aeronautics and Space Administration hopes to contract with commercial spaceflight providers to conduct short missions to the space station. While those craft are being developed, astronauts will rely on the Russian Soyuz craft.
