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Two NASA astronauts from the space shuttle Discovery, have carried out the first of two planned spacewalks.
The spacewalk intends to support maintenance of the International Space Station. It is scheduled to last six-and-a-half hours. Discovery reached the space station on Saturday, for its final mission at the 100-billion US-dollar orbital outpost. The shuttle is scheduled to spend a week at the station, though NASA is considering adding an extra day. NASA is ending its 30-year shuttle program in about six months.
Sister ships Endeavour and Atlantis .. are expected to make their final flights this spring and summer. The US is retiring the program due to high operating costs, and to develop spaceships that can travel to the moon, asteroids, and other destinations beyond the station's orbit.