European satellite to rival NASA

A gigantic rocket carrying the largest satellite ever built in Europe will be hurled into space early tomorrow - its mission to be a guardian of Earth's fragile environment.

The satellite Envisat - costing £1.5 billion and bigger than the biggest articulated lorry - will blast off in a 52 metre Ariane Five rocket from a spaceport in the swamps of French Guiana, South America.

Once in orbit 500 miles high, it will sweep the entire surface of the Earth every 35 days to provide scientists with the fastest and most detailed facts yet on climate and ecosystems, including global warming, melting icecaps and rising sea levels,air pollution and the ozone layer.

The knowledge will be vital in helping world leaders plan to avert any future environmental crisis.

It may also save thousands of lives by measuring the sw elling lava dome of a volcano about to erupt, and shedding light on natural disasters from floods to earthquakes. By tracking ocean currents and wave heights it can guide shipping, and it will keep watch on the El Nino effect that plays havoc with weather.

It has taken 14 years for the British-led European project - Canada is also taking part - to build the 25m high, 10m wide,8.2 tonne satellite, packed with technology.

It carries 10 instruments including spectrometers to measure gases in the atmosphere and ocean water quality. Radars and radiometers will build up images of terrain and temperature. Others can measure Envisat's position so accurately they could detect subsidence in a city street of as little as a millimetre a year.

Eleven British firms have played a major part. Envisat's main structure was built here.Astrium UK, based in Portsmouth, Stevenage and Bristol, was the leading contractor and developed three instruments.

The European Space Agency (ESA)said Envisat gives Europe "the best eyes possible" with which to look at the world, rivalling NASA. It said the cost was about seven Euros per European Union citizen: the price of a cup of coffee for each year of the satellite's projected lifespan of at least five years - making 14 orbits a day." With Envisat we can play in the big leagues," said ESA scientist John Burrows.

One worry remains: will Envisatget into orbit? Three of 10 Ariane Five launches have failed, the first exploding in 1996, destroying a payload of satellites. However the rocket has been modified since, and Dr Colin Hicks, director general of the British National Space Centre, said he was "as confident as is possible with any launch".

Current take-off time is 1.07am GMT tomorrow from the ES launch pad at Kourou.