Historic Launch Set To Be Busiest Yet

At Sunday morning's final countdown status briefing from NASA's Kennedy Space Center in Florida, NASA Test Director Charlie Blackwell-Thompson said that the countdown timeline is on target and "Atlantis is ready to fly." Final preparations continued throughout the day at Launch Pad 39A, and the rotating service structure that surrounds Atlantis was rolled back into its launch position late in the afternoon.

Shuttle Weather Officer Kathy Winters improved on the forecast, now giving the team a 90-percent chance to launch Atlantis at 2:01 p.m. EDT tomorrow without weather interfering.

Altman will command the final space shuttle mission to service NASA's Hubble Space Telescope, and retired Navy Capt. Gregory C. Johnson will serve as pilot. On Sunday, STS-125 Altman and Johnson once again practiced landings in the Shuttle Training Aircraft as the entire crew readies for their mission to service NASA's Hubble Space Telescope. Mission specialists rounding out the crew are: veteran spacewalkers John Grunsfeld and Mike Massimino, and first-time space fliers Andrew Feustel, Michael Good and Megan McArthur.

During the 11-day mission's five spacewalks, astronauts will install two new instruments, repair two inactive ones and perform the component replacements that will keep the telescope functioning into at least 2014.

In addition to the originally scheduled work, Atlantis also will carry a replacement Science Instrument Command and Data Handling Unit for Hubble. Astronauts will install the unit on the telescope, removing the one that stopped working on Sept. 27, 2008, delaying the servicing mission until the replacement was ready.

FMI: www.nasa.gov/mission_pages/shuttle/launch/launch_blog.html