Discovery managed to dodge unidentified space debris Sept. 10 but was unable to overcome stormy East Coast weather as NASA called off the scheduled landing for the space shuttle returning from its cargo mission to the International Space Station. Discovery will remain in orbit at least another day as flight controllers study the weather conditions around Kennedy Space Center.
Originally scheduled to land at 7:05 p.m., NASA waved off the landing due to unstable and uncooperative weather conditions. When the weather did not improve, NASA scratched an 8:42 p.m. landing attempt.
NASA is still undecided about switching landing sites on Sept. 11 to Edwards Air Force Base in California. While that decision is still being decided, NASA listed 5:48 p.m. and 7:23 p.m. as possible landing times Sept. 11 at Kennedy Space Center.
Earlier in the day as Discovery's seven-person crew prepared for landing after their 13-day mission, which has been plagued with minor glitches from launch to docking at the ISS, had to maneuver the craft to avoid a collision with what NASA called "mystery orbital debris." NASA said the debris is believed to be from the mission's third spacewalk.
NASA admitted it did not know the size of the object but the debris crept closer to Discovery throughout the morning. By 1 p.m., NASA estimated the unknown object would encroach within Discovery's security perimeter that extends approximately 25 miles out and two miles above and below the craft.
"Based on the latest tracking data, the object will move in and out of that box over the course of 11 consecutive orbits," said NASA's Pat Ryan. Discovery safely moved past the mystery debris by performing an orbital adjustment burn at 12:02 p.m.
The mission, while successful, was plagued throughout the scheduled 13-day trip by stormy launch weather and faulty sensors.
During 8.5 days docked at the ISS, the Discovery's crew delivered and unpacked more than seven tons of supplies, science racks and equipment, as well as additional environmental hardware to sustain six crew members on the orbital outpost. Discovery is returning to Earth with more than 5,000 pounds of trash, surplus items and scientific experiments.
Over the course of three spacewalks, the Discovery crew replaced a large coolant tank and retrieved experiments from the station's hull, in addition to completing minor repair jobs.
The mission also marked a crew change at the space station with NASA astronaut Nicole Stott replacing American Tim Kopra, who has completed a two-month tour of duty aboard the ISS. Stott is scheduled for a three-month stay.
Discovery's crew also delivered the COLBERT (Combined Operational Load Bearing External Resistance Treadmill) treadmill, an exercise device named after comedian Stephen Colbert. Construction of the $5 million high tech treadmill will not begin until after Discovery has departed.