KENNEDY SPACE CENTER, Fla. Nov. 7 — The shuttle Discovery glided to a safe landing here Wednesday, bringing to a close an eventful mission that combined challenging space station construction and emergency repairs.

Commander Pamela A. Melroy fired the shuttle’s braking rockets just before noon, Eastern time, beginning the return from orbit. The shuttle flew over North America from the northwest to the southeast and landed on the 15,000-foot landing strip shortly after 1 p.m.

The shuttle, which glides to its landing without power, could be seen passing high above the landing site as a speedy white dot. Its distinctive double sonic ba-BOOM could be heard moments after it passed overhead, bringing applause from the spectators at the runway. Commander Melroy then brought the craft around for its final approach, heading into a stiff headwind and touching down.

The mission started out as a pivotal moment in station construction, tightly packed with goals that included bringing up a new room — the Harmony module — and relocating an enormous solar array and truss from its temporary position atop the station to its permanent location on the left side. Moving the 35,000-pound array required two spacewalks and a nimble handoff between the robotic arms of the shuttle and station.