A shuttle launches from the Kennedy Space Centre in Florida

NASA shuttle launch targeted for no earlier than March 15

Space shuttle Discovery's launch to the International Space Station now is targeted for no earlier than March 15.

NASA managers postponed Wednesday's planned liftoff due to a leak associated with the gaseous hydrogen venting system outside the external fuel tank. The system is used to carry excess hydrogen safely away from the launch pad.

Liftoff on March 15 would be at 7:43 p.m. EDT. The exact launch date is dependent on the work necessary to repair the problem. Managers will meet Thursday at 4 p.m. to further assess the troubleshooting plan.

Discovery's STS-119 flight is delivering the space station's fourth and final set of solar array wings, completing the station's truss, or backbone. The arrays will provide the electricity to fully power science experiments and support the station's expanded crew of six in May.

The 14-day mission will feature four spacewalks to help install the S6 truss segment to the starboard, or right, side of the station and the deployment of its solar arrays.
The flight also will replace a failed unit for a system that converts urine to potable water.

Japan's Koichi Wakata, KC5ZTA

Commander Lee Archambault is joined on STS-119 by Pilot Tony Antonelli and Mission Specialists Joseph Acaba, KE5DAR, Steve Swanson, Richard Arnold, KE5DAU, John Phillips, KE5DRY, and Japan Aerospace Exploration Agency astronaut Koichi Wakata, KC5ZTA.

Wakata will replace space station crew member Sandra Magnus, KE5FYE, who has been aboard the station for more than four months. He will return to Earth during the next station shuttle mission, STS-127, targeted to launch in June 2009.