Bad weather has forced a delay to the final launch of Europe's Ariane 4 rocket.

It was scheduled to blast off early on Wednesday from Kourou in French Guiana.

"Wind conditions are not compatible for a launch," said Jean-Charles Vincent, director in Kourou of rocket operator Arianespace.

He said that weather conditions would be reviewed on Wednesday evening; it is hoped the launch will go ahead on Thursday.

Ariane 4

Entered service in 1988 Final mission cleared for launch on 12 Feb Payload: Intelsat 907 telecommunications satellite

The company said in a statement: "The speed and direction of high altitude winds led Arianespace to stop the launch countdown seven hours before the scheduled liftoff, which had been set for the early morning hours of February 12."

A decision for the next launch attempt will be "based on the evolving weather conditions", it added.

Setbacks

The Ariane 4, the workhorse of the European space industry, is being retired to pave the way for the giant Ariane 5, capable of hurling larger loads into orbit.

Its 116th and final launch will mark the end of an era for the European Space Agency (Esa) and Arianespace.

Flight 159 was to be a triumphant event but the loss of the space shuttle Columbia and problems with the new launch vehicle have cast a shadow over space exploration.

The European space industry must now rely on the Ariane 5 rocket, which has a poor track record.

Out of 14 launches so far, two rockets have exploded and two have put satellites into the wrong orbits.

The latest setback was on 11 December, when a new heavyweight version of the Ariane 5 veered off course and had to be destroyed minutes after launch.

Esa was later forced to delay its billion-euro comet-chasing probe, Rosetta, because of doubts over the Ariane 5.

It has shaken confidence, said Dr Andrew Coates from University College London's Mullard Space Science Laboratory.

He believes there is an argument for keeping the Ariane 4 for longer, although that would require a policy decision.

Bigger, cheaper

The phasing out of the Ariane 4 is borne out of the need to put bigger commercial satellites into orbit at a cheaper cost.

Boeing's new Delta 4 went up on 20 November

"Everyone's trying to build bigger launchers at the moment," he said. "Commercial payloads are getting heavier and the launcher builders want to provide better value for money for their customers because the market place for large commercial launchers is very crowded."

It took Esa 10 years and $7bn to produce the Ariane 5, a rocket intended to give Europe dominance in the commercial space business.

The recent failure of the new beefed-up version of the rocket will play into the hands of its competitors, Lockheed Martin's Atlas 5 and Boeing's Delta 4.

It comes amid a backdrop of budget constraints, a shrinking satellite launch market and the recent reminder of the dangers of putting astronauts into space.