CAPE CANAVERAL, Fla. (AP) - NASA is repairing a leaky hydrogen gas line on Endeavour's fuel tank in hopes of launching the shuttle Wednesday, four days after the first try was called off.
But another NASA mission, involving a pair of science spacecraft bound for the moon, is also scheduled to blast off that day.
NASA officials will decide tomorrow whether to bump the moon mission to make way for Endeavour's liftoff for its space station repair mission.
The head of the mission management team says it's likely the shuttle will go first - if the repair of the leaky line goes well, no other problems crop up and if there's good launch weather.
As for the launch weather, forecasters put the odds of favorable conditions at 70% for the shuttle early Wednesday morning.
Hydrogen gas began leaking from a vent line hookup on Endeavour's external tank during fueling early Saturday, and the countdown was halted just hours before the scheduled morning liftoff.
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