March 9, 2009

Countdown under way for Discovery’s launch

The U.S. space agency says the countdown has started for the planned launch of space shuttle Discovery on Wednesday.

The official countdown for the STS-119 mission to the International Space Station started at 7 p.m. EDT Sunday, with the launch scheduled for 9:20 p.m. EDT Wednesday, the National Aeronautics and Space Administration said.

Shuttle commander Lee Archambault and his six crew mates are to deliver the space station's fourth and final set of solar array wings. The 14-day mission will include four spacewalks to install the S6 truss segment and to deploy the new set of solar arrays, NASA said. The flight also will replace a failed unit for a system that converts urine to potable water.