After waiting two and a-half years to re-launch the space shuttle, NASA might have to sit tight for at least a few more days.
Today's scheduled launch of "Discovery" was scrubbed because of a faulty fuel gauge. And a launch control commentator says it's unlikely the problem will be quickly fixed.
The same problem happened during a launch pad test back in April, and NASA has been struggling ever since to figure out the source of the trouble.
As recently as Monday, NASA's deputy shuttle program manager called the sensor problem an "unexplained anomaly."
NASA only has until the end of July to launch Discovery, after which it will have to wait until September.
The schedule is driven by the position of the international space station and NASA's desire to hold a daylight liftoff in order to photograph the shuttle during its climb to orbit.