NASA is now targeting next Wednesday for the launch of space shuttle Discovery.

The mission has been delayed repeatedly over the past month for tests on critical engine valves.

Shuttle managers decided Wednesday to move up liftoff by one day. They say they are confident that the three latest hydrogen gas valves aboard Discovery are free of cracks and will perform as expected during launch.

Top officials will meet Friday to finalize the date.

The launch was initially scheduled for Feb. 12 but NASA wanted to run extra tests on the valves. One of the pressure valves cracked during the last shuttle launch in November.

Discovery and its seven-man crew are set to deliver the last set of solar wings to the international space station.

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