NASA is fueling space shuttle Discovery for a Monday morning launch.
Discovery is scheduled to blast off at 6:21 a.m. EDT, nearly an hour before sunrise. The shuttle and its crew of seven will deliver spare parts and science experiments to the International Space Station.
Forecasters say the odds of good weather are 80 percent.
The launch team reported to duty Sunday night. After running some tests to check out a voltage spike on a fuel cell, controllers began filling Discovery's external fuel tank.
This is one of four remaining shuttle flights. NASA plans to end the program this fall.
The space station received three new residents Sunday _ one American and two Russians. They wished everyone a happy Easter after their Russian spacecraft docked.