KENNEDY SPACE CENTER, Fla. -- The shuttle Discovery glided to a safe landing here yesterday, bringing to a close one of the more eventful shuttle missions in the history of the shuttle program.
Commander Pamela A. Melroy fired the shuttle's braking rockets just before noon, beginning the return from orbit. The shuttle flew over North America from the northwest to the southeast, coming in to a landing on the 15,000-foot landing strip about 1 p.m.
The mission started out as a pivotal moment in space station construction, tightly packed with goals that included bringing a new room to the station - the Harmony module - and relocating an enormous solar array and truss from its temporary position atop the station to its permanent location at the left-hand end of the station. Moving the 35,000-pound array required two spacewalks and a nimble handoff between the robotic arms of the shuttle and station.
The first three spacewalks went smoothly, and the truss was moved successfully. But two problems caused mission managers to change their plans for the remainder of the mission.
The first was a problem with a rotary joint on the right side of the solar array that keeps the right-side arrays facing the sun. During the third spacewalk, Daniel M. Tani removed a cover from the joint and peeked in, and found that it was fouled with metal shavings, suggesting that some part of the joint was being ground down.
Mission managers decided to change plans for the fourth spacewalk and devote it instead to a thorough examination of the joint. But last week, as astronauts inside the station opened the newly moved solar array, a guide wire snagged on one of the folding panels' hinges and tore two holes in the 110-foot-long array. The spacewalk plans were changed again, this time to be devoted to a high-stakes, high-risk attempt to repair the torn array.
On Saturday, Scott E. Parazynski rode the station robotic arm, extended with a sensor boom from the shuttle, to repair the array. The boom barely reached the spot, and Parazynski had to be careful not to touch any of the electrically charged parts of the array.
The cufflink-like straps held, taking the strain off the material around the tears, which allowed the damaged array to be fully extended.
The shuttle brought Clayton Anderson back to Earth; he lived and worked aboard the station since June.
In interviews from space Tuesday, he said that he expected readjustment to gravity to be a little rough. "I'm kind of optimistic, maybe overly so," about his physical preparedness to deal with gravity again, he said.
The end of this mission sets off a scramble aboard the International Space Station to prepare for the next one. A new laboratory module, known as Columbus, could be brought up aboard the shuttle Atlantis as early as Dec. 6.