NASA has successfully launched the space shuttle Atlantis following a series of delays due to technical problems.
Six astronauts are taking part in the eleven-day mission to the international space station.
It is the first construction mission since the Columbia shuttle disaster in 2003.
Weather problems initially caused the postponement of the operation last week when the launch pad was struck by lightning.
The incident prompted a two-day review to check the shuttle and ground equipment. Then the spacecraft was temporarily removed from the launch site because of threatening winds from a tropical storm.
This week's delays were caused by technical concerns. In particular an unusual voltage spike in one of the shuttle's electricity generators and the unwelcome return of a mysterious fuel sensor problem that dogged NASA last year.
With Atlantis' flight, NASA plans to restart construction of the International Space Station, which has been on hold since the Columbia accident.
The crew intends to deliver and install a $372 million solar power module.
