Shuttle begins landmark mission

Discovery goes for 100

The US space shuttle Discovery has lifted off from the Kennedy Space Center in Florida to continue the construction work on the International Space Station (ISS).

It was a case of fifth time lucky for Discovery. Four previous attempts at blast-off were aborted due to bad weather and technical hitches.

But heavy rain clouds cleared from the skies above the launch area about an hour before the scheduled departure time allowing Discovery to head skywards at 1917EDT (2317GMT) on what is the 100th flight for the space shuttle programme.

"We're going to take a big step here. Let's go!" commander Brian Duffy called out moments before the shuttle began its nine-minute climb into orbit.

Electric cables

"All good things are worth waiting for, and I think you and your crew have waited long enough for this one," launch director Mike Leinbach told the astronauts.

Discovery will meet up with the ISS on Friday

"Good luck on this extremely important mission to the International Space Station - and have fun."

The ISS is orbiting the Earth at an altitude of about 380 kilometres (240 miles). Discovery must chase the station before it can link up and begin adding two new segments to the platform.

A docking procedure is scheduled for Friday.

Discovery's crew of seven astronauts includes Koichi Wakata of Japan. He will operate the shuttle's robotic arm to manoeuvre the segments into a position where they can be bolted on to the station.

Expedition One

One of the segments, known as the Z-1 Truss, carries gyroscopes that will help the ISS maintain its position in space. The other component is a connection node to allow future shuttle docking.

Koichi Wakata will operate the shuttle's robotic arm

Four spacewalks will be required to connect cabling to the new components.

Discovery will return to Earth on 22 October. Eight days later, a three-man US-Russian crew, the first residents of the ISS, are due to blast off from Russia's Baikonur cosmodrome in Kazakhstan aboard a Soyuz rocket.

Expedition One, as it is called, will include US astronaut William Shepherd and the Russian cosmonauts Sergei Krikalev and Yuri Gidzenko. They will remain aboard the ISS until February 2001, when a US space shuttle will bring them back to Earth.

The 16-nation space station project is expected to be completed in 2006, but work in the ISS lab will continue until at least 2013.

A Space Odyssey

In honour of the 100th shuttle launch, a videotape was played for guests at the Kennedy Space Center featuring shuttle scenes and the Philadelphia Orchestra playing the theme from 2001: A Space Odyssey. The orchestra is marking its 100th anniversary.

The space shuttle programme will celebrate its 20th anniversary in April.

Since the first journey, space shuttles have carried 1.36 million kilograms (3 million pounds) of cargo into space and 596 passengers.

The shuttle fleet has cumulatively spent almost 2 ½ years in orbit and amassed almost 15 years of passenger-hours in flight.

More than 850 payloads have been flown, and the shuttle has deployed more than 60 payloads and retrieved more than two dozen.