Columbia crew has difficult mission

CAPE CANAVERAL, Fla., Aug. 25 (UPI) -- Sunday's scheduled launch of the space shuttle Atlantis in Florida will begin what is viewed as one of NASA's most challenging missions.

Charged with resuming construction of the International Space Station, the Atlantis crew will be installing equipment that has never been used before, USA Today reported.

Atlantis commander Brent Jett and his fellow astronauts will have to work in perfect coordination with flight controllers in Houston in order to keep the space station running while it undergoes a major renovation.

"Over the next 18 months, not only are we going to double the size (of the station), it really does represent the most difficult spacewalking and robotic activities we have ever done, Paul Hill, shuttle manager for mission operations, told the newspaper.

Work on the space station was halted in 2003 after the Columbia disaster while multiple re-designs have delayed completion of the project.

Weather permitting Atlantis is to lift off from the Kennedy Space Center at 4:30 p.m. EDT.