A group of NASA worker discuss the progress of the space shuttle Discovery as it hangs in it's sling in the Vehicle Assembly Building at the Kennedy Space Center in Cape Canaveral, Florida, March 29, 2005. Discovery will be lifted vertical to the top of the building, then turned, lowered and attached to the solid rocket boosters and external fuel tank. NASA passed a significant milestone in it's two year quest to return the shuttle fleet to flight. (Reuters photo)

BEIJING, March. 30 (Xinhuanet) -- NASA's Space Shuttle Discovery is now one important step closer to launch. It has been rolled from its hangar to the Vehicle Assembly Building early Tuesday morning.

    Discovery will be attached to its propulsion elements, a redesigned External Tank (ET) and twin Solid Rocket Boosters (SRBs), at NASA's Kennedy Space Center, Fla.

    "This is a tremendous accomplishment for the Space Shuttle program," said Bill parsons, Space Shuttle Program Manager.

    "This effort has taken a talented team dedicated to meticulously preparing the vehicle and implementing all the modifications for a safe Return to Flight," he added.

    Work on Discovery in the VAB includes installation of a new digital camera, testing electrical and mechanical attachments between the orbiter and ET and umbilical checks.

    Discovery's launch window is from May 15 to June 3. Its mission, designated STS-114, will take Commander Eileen Collins and six crew members to the International Space Station.

    Discovery underwent 41 modifications to be in compliance with the recommendations set by the Columbia Accident Investigation Board.

    "I could not be more proud of the team that spent the last two years working on Discovery. We are extremely excited to reach this point in the processing for flight," said Stephanie Stilson, NASA Vehicle Manager for Discovery.

    "Seeing the orbiter roll to the VAB is the culmination of all of that hard work. We look forward to a safe Return to Flight," she said.

    Discovery also completed its Orbiter Major Modification (OMM) period that began in September 2002. Technicians completed 107 additional modifications to Discovery, 17 will be flying for the first time.

    OMMs are scheduled at regular intervals to enhance safety and performance and to infuse new technology.

    The next Return to Flight milestone is scheduled early next week, when Discovery begins its four mile journey to Launch Pad 39-B.

    (Agencies)