Space shuttle Endeavour and its crew of five glided to a landing Monday after an 11-day flight that was dogged by everything from a wobbly satellite to a clogged toilet pipe.
The landing coincided with NASA's verdict on Endeavour's O-rings, which had to be reinforced before the mission.
It was good news: O-ring seals in the nozzle joints of the solid-fuel rocket boosters came back unscathed for the first time in months. That clears the way for next week's launch of space shuttle Columbia.
On NASA's two previous shuttle flights, in June and July, the O-rings in the nozzle joints were scorched by hot rocket gas that escaped through air pockets in thermal insulation. Endeavour's flight was put on hold for about a month as technicians replaced insulating putty using a new technique.
Endeavour's two rocket boosters fell into the Atlantic Ocean as planned a few minutes after launch Sept. 7. It wasn't until they were retrieved and inspected that NASA could declare the new repair method sound.
Unlike much of Endeavour's flight, the landing was virtually flawless.
Commander David Walker guided Endeavour to a smooth touchdown on the concrete runway at Kennedy Space Center shortly after sunrise, right on time.
The primary objective of the mission was releasing and retrieving two research satellites.
But one of them--a satellite designed to study solar wind, the charged particles streaming from the sun that can disrupt radio signals on Earth--was spinning and turned the wrong way when the crew went to recover it.
The other satellite, a 12-foot steel dish designed to grow ultra-thin superconductor film in the pure vacuum of space, overheated, wobbled and even flipped once, producing less film than planned.
Mission snags included the clogged toilet. Astronauts spent their last full day in orbit dumping urine into an emergency container.