George Diller/NASA Launch Commentator: From Launch Complex 39 at the Kennedy Space Center in Florida,
this is Shuttle Launch Control at T-3 hours and holding.
We are now in the final 5 1/2 hours of the countdown for the launch of Atlantis on mission STS-125.
The countdown is being controlled from Firing Room 4 in the Launch Control Center.
We're on schedule for liftoff, targeted for 2:01 p.m. Eastern time.
This is the 126th launch of the Space Shuttle Program, the 30th launch of space shuttle Atlantis,
and the fifth mission for maintenance of the Hubble Space Telescope.
There are five EVA's, or spacewalks, planned for this mission, which is scheduled to last 11 days.
Landing is currently planned for May 22, at 11:41 a.m.
There are seven astronauts who will shortly be aboard Atlantis en route to a rendezvous with the Hubble Space Telescope.
The astronauts are Commander Scott Altman, Pilot Greg Johnson,
Mission Specialists Michael Good, Megan McArthur,
John Grunsfeld, Mike Massimino and Andrew Feustel.