NASA Scrubs Space Shuttle Discovery Launch

NASA officials scratched the scheduled March 11 launch of the space shuttle Discovery after detecting a leaky gaseous hydrogen (GH2) vent line. Scheduled for a 9:20 p.m. EDT blastoff from the Kennedy Space Center in Florida, NASA scrubbed the launch at 2:37 p.m.

The vent line is at the intertank region of the external tank and is the overboard vent to the pad and the flare stack where the vented hydrogen is burned off. The NASA launch team will meet later March 11 to discuss the problem. Depending on what repairs are needed, NASA said it is keeping the option open for a March 12 launch at 8:54 p.m.

The eight-man Discovery crew is scheduled to deliver the International 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 ISS crew of six. Four spacewalks are scheduled for the 14-day mission as the ISS crew installs the solar array wings. The mission also includes replacing a failed unit for a system that converts urine to potable water.

The Discovery mission has already been delayed by a month after safety concerns were raised about the craft's fuel pressure valves. The mission is the first of five Shuttle missions scheduled for this year.

Commander Lee Archambault will lead Discovery's crew of seven, along with pilot Tony Antonelli, and mission specialists Joseph Acaba, John Phillips, Steve Swanson, Richard Arnold and Japan Aerospace Exploration Agency astronaut Koichi Wakata.

The delayed Shuttle launch follows mixed results for NASA launches this year. NASA's Orbiting Carbon Observatory launch failed Feb. 24 to separate from its launch rocket or reach orbit, and tumbled into the Pacific Ocean near Antarctica. NASA's first spacecraft dedicated to studying atmospheric carbon dioxide, the OCO aimed to scan Earth's surface for elusive carbon dioxide "sinks" in Earth's atmosphere.

More successfully, NASA launched March 6 the unmanned Kepler project, a three-year or longer mission in search of Earth-sized planets moving around stars similar to the sun. The Kepler spacecraft will watch a patch of space containing about 100,000 such stars. Unlike other space observatories such as the Hubble Space Telescope, Kepler's space position will allow it to watch the same stars constantly throughout its mission.

Provisioned with special detectors similar to those used in digital cameras, Kepler will look for slight dimming in the stars as planets pass between the stars and Kepler.