Discovery is targeting a landing later today, after poor weather conditions in Florida and California kept the crew in space two days longer than originally planned. Duffy and his crew mates - Pilot Pam Melroy and Mission Specialists Leroy Chiao, Bill McArthur, Jeff Wisoff, Mike Lopez-Alegria and NASDA Astronaut Koichi Wakata - will begin their preparations for a return trip to Earth about 8:30 this morning, in anticipation of a landing at either the Kennedy Space Center or Edwards Air Force Base later today.
With continuing strong winds, cloud cover and rain at the Florida landing site, a landing there today remains unlikely. However, there is one opportunity for the crew to land in Florida if weather conditions improve significantly. That opportunity would see a deorbit burn at 1:21 p.m. with landing to follow at 2:28 p.m. An opportunity to return to KSC one orbit earlier, on Orbit 200, has already been ruled out due to the crew's activity timeline
On the west coast, improving weather conditions at Edwards Air Force Base hold promise for Discovery's return. Entry Flight Director LeRoy Cain and his team will watch over the weather this morning and likely will adjust the crew's deorbit timeline to focus on the Edwards opportunities today.
On the first of two opportunities to land at Edwards today, Discovery's orbital maneuvering system engines would fire in a deorbit burn at 2:52 p.m. as it passes over the Indian Ocean, just north of Madagascar and east of Kenya, and land at 3:59 p.m. Discovery would encounter the first traces of the atmosphere while flying over the South Pacific, just south of the Tropic of Capricorn and east of Australia and continue its flight over the Pacific, passing well South of the Hawaiian Islands before arriving on the west coast of the United States. As it heads into Edwards Air Force Base, Discovery will pass just south of the Santa Rosa and Santa Cruz Islands before crossing the California coastline over Los Angeles.
There is a second opportunity to Edwards with a deorbit burn starting the descent at 4:29 p.m. and landing at 5:35 p.m. A landing today brings to a close the 100th mission in Shuttle program history on a mission that paved the way for the first residents of the orbiting International Space Station.