Mike Curie/STS-131 Launch Commentator: Standing alone on one of the world's most prized pieces of oceanfront
property and lit up like a four-and-a-half-million-pound candle, space shuttle Discovery is fully fueled and
ready for its early morning liftoff from Launch Pad 39A here at Kennedy Space Center in Florida.
Discovery's bright-orange external tank is filled with more than 500,000 gallons of liquid hydrogen and liquid oxygen.
The shuttle's power-producing fuel cells, general purpose computers and life support
systems are all activated and everything is working as expected.
About three and a half miles away from Discovery, launch controllers in Kennedy's Launch Control Center
Firing Room 4 are overseeing all of the shuttle's systems and verifying the step-by-step processes that
will lead to an expected liftoff at 6:21:25 a.m. Eastern Daylight Time.
Discovery's crew was awakened at 8 p.m. Easter Sunday, ate breakfast at 8:30, underwent standard medical
checks at 9 o'clock, and has been making last-minute preparations for this morning's launch attempt.
This will be the 35th night launch in Space Shuttle Program history. And as the shuttle rockets to the northeast,
it will make an early morning wakeup call to residents of the space coast as well as much of America's east
coast as it climbs and accelerates to 17,500 mph in just eight and a half minutes.
Right after the launch tower is cleared, Discovery will perform a roll maneuver,
pointing it precisely on the trajectory of 51.6 degrees to catch up to the International Space Station.
At the time of liftoff, the space station will be about 220 miles over the Atlantic Ocean, southwest of Ireland.
But about 17 minutes before launch, at 6:04 a.m., the space station will pass over the Kennedy Space Center,
providing an excellent sighting opportunity as it moves from the south-southwest to the east.
And it should be visible for about three minutes, peaking at a 43 degree elevation.
So, here inside the Launch Control Center, the countdown for Discovery's launch is continuing on schedule.
The launch window opens at 6:16:25, and our preferred and planned launch time is exactly five minutes later at 6:21:25.
The launch window for a Flight Day 3 rendezvous closes at 6:26:25, and for a
Flight Day 4 rendezvous three minutes later at 6:29:35.
NASA managers have determined that they would use the Flight Day 4 opportunity, if it became necessary.
We're at T-3 hours and holding, this is Shuttle Launch Control.