The successful launch of the Space Shuttle Endeavour

It was a perfect blast-off for Endeavour. It left the launch pad at Cape Canaveral, Florida, right on schedule at 0335 EST (0834 GMT).

There was no repeat of the aborted launch on Thursday when an alarm had sounded in the Shuttle cockpit forcing Endeavour to stand down for 24 hours.

Zarya is the target

NASA managers told a post-launch news briefing that the Shuttle's take-off had gone smoothly, with no problems. "We've got effectively a perfect vehicle in orbit," Donald McMonagle, the shuttle director at Kennedy Space Centre, said.

Several hours earlier, Endeavour's crew had strapped themselves into the space vehicle determined to get their 11-day mission underway.

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"We're ready to start on a new era of international co-operation in space and get this space station built," said Endeavour commander Robert Cabana moments before the final launch sequence began. "Let's go do this."

Endeavour is now chasing the Zarya module, the first component in the space station project. It was launched last month from the Baikonur cosmodrome in Kazakhstan.

Delicate manoeuvres

It will take two days for the Shuttle to catch up with the Russian module. It will then have to perform a series of delicate manoeuvres to get into the right position to grab Zarya with its robotic arm. This should happen at about 1850 EST (2350 GMT) on Sunday.

The lift-off from Cape Canaveral

If all goes to plan, Endeavour will then attach a 13-tonne, six-sided hub called Unity to Zarya. Astronauts Jerry Ross and James Newman will then put on their spacesuits and go outside the orbiter to join all the electrical connections and cables by hand. They will also attach handrails and other tools for future crews.

A perfect launch

Endeavour will also deploy two experimental satellites: an Argentine one called SAC-A, and a US satellite called MightySat 1, developed by the US Air Force Phillips Laboratory.

The Unity module will become the primary docking port for future shuttle missions during construction of the multi-billion-dollar space station. A third, Russian module will be sent up in mid-1999.

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This will be the crucial mission in the early construction of the space station because the power from the third module will allow the growing structure to maintain a constant orbit.