Space shuttle Discovery and its seven-member crew have landed safely at the Kennedy Space Center in Florida.
Shuttle managers decided conditions in Florida were good enough to bring the shuttle home at 1732 (2232 GMT), after days of uncertainty about the weather.
The shuttle has been on a 13-day mission to rewire the International Space Station (ISS).
Its safe return concludes Nasa's third shuttle flight of the year. Five more flights are planned for 2007.
The shuttle gave off twin sonic booms as it descended towards the floodlit runway.
"You've got seven thrilled people right here," Discovery commander Mark Polansky told Mission Control after touching down.
"We're just really proud of the entire Nasa team to put this together, so thank you."
The team spent eight days rewiring the space station. They also fitted a connecting segment that will allow the platform's backbone to be extended further in future.
They delivered two tonnes of supplies and dropped off one new resident, American Sunita Williams, and picked up a returning astronaut, German Thomas Reiter.
The shuttle touched down after the weather had prevented an earlier landing.
Rain over Florida and wind at back-up site Edwards Air Force Base in California led to some last minute suspense over where the shuttle would land, with officials clearing Florida only an hour before the landing.
Discovery needed to be on the ground by Saturday, or it would have run low on the fuel that powers its electrical systems.
The shuttle would normally have had more time to make a landing, but astronauts made an unscheduled, extra spacewalk at the station to free a stuck solar array.
The next construction mission to the ISS will be undertaken by the Atlantis shuttle in March. This will see a third set of solar arrays and batteries fitted to the station.
May should see the maiden flight of a new re-supply vessel for the station.
Known as the Automated Transfer Vehicle (ATV), it will be launched on an Ariane 5 rocket from the European spaceport at Kourou in French Guiana.
Europe also has keen interest in Discovery's next mission, scheduled for October.
This mission will deliver the Columbus science module, Europe's biggest contribution to the ISS project.