Washington - The aging space shuttle Discoveryroared from its Florida launch pad at 1538 GMTTuesday, streaking into a two- week mission to expand the orbiting ISS. The Discovery shuttle, on its 34th mission in 24 years, accelerated to 16,000 kilometres an hour within seven minutes of takeoff.
The launch went ahead despite worries about ice that formed outside as supercooled hydrogen and nitrogen were pumped into the tank.
Nervous safety engineers had also advised a delay to repair three defective heat shield tiles on the leading edge of Discovery's wings. In February 2003, a defective tile was blamed for the disintegration of Columbia shuttle upon re-entering Earth's atmosphere.
The seven astronauts on board are led by the second woman commander in shuttle history, Pamela Melroy. When Discovery arrives at the International Space Station, she will meet another female commander who is in charge of the orbiting three-astronaut crew.
Italian astronaut Paolo Nespoli, of the European Space Agency, was making his first flight.
They face a packed programme of five space walks, with huge construction projects including an addition of the first new room in six years to the International Space Station, where the three orbiting astronauts will help in the tasks.
The past several shuttle missions have transported and mounted huge solar panels outside the station, in preparation for expanding the orbiting crew and work space by 2010, when NASA intends to retire the shuttle programme.
The major push on this mission focusses on installing the Harmony module to serve as a port for additional international laboratories constructed in Japan, Germany and elsewhere. The European module Columbus is to be attached to Harmony in December.
