Looks like the next Shuttle flight has been postponed from May to July. NASA reports:

NASA Announces New Window for Next Shuttle Mission
On March 14, NASA announced July 1 to 19, 2006, is the new launch planning window for Space Shuttle Discovery's mission (STS-121). The window gives the agency time to do additional engineering work and analysis to ensure a safe flight for Discovery and its crew.

Space Shuttle Program Manager Wayne Hale made the announcement during a news conference from NASA's Johnson Space Center in Houston. The decision to target July followed a two-day meeting on the external fuel tank's engine cutoff (ECO) sensors. The sensors indicate whether the tank still has fuel during liftoff. During testing, one of the four ECO sensors had a slightly different reading than is expected. Shuttle officials have decided they will remove and replace all four liquid hydrogen sensors.

+ Read More
+ View Briefing Transcript (87 Kb PDF)
+ STS-121 Mission | + STS-121 Crew

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