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Friday, 1 March, 2002, 16:36 GMT
'Green' satellite points to Earth
Controllers were pleased with the launch
The rocket took off from French Guiana

Europe's largest and most expensive satellite is functioning well after entering space in the early hours of Friday.

Its solar array is pointing at the Sun and the spacecraft has begun manoeuvring into its final orbit, 800 kilometres (500 miles) above the Earth.

The 1.4bn Environmental Satellite (Envisat) was blasted into space aboard a giant Ariane 5 rocket from Europe's spaceport in Kourou, French Guiana.

It was only the 11th launch of an Ariane 5 rocket and the biggest payload to be carried so far.

Clapping and cheering

The satellite separated from the rocket as expected 26 minutes after lift-off and then began to unfurl its solar panels.

Ariane 5, BBC
The rocket sped north out over the ocean
Mission managers at the Jupiter Control Room in the Guiana Space Centre clapped and cheered when news came through that the procedure had been successful.

The spacecraft is now in the hands of controllers at the European Space Agency's operations centre (Esoc) in Darmstadt, Germany.

At a media briefing in the Guiana Space Centre, Patrick Loire of Arianespace said that the spacecraft had entered "an excellent orbit".

This means that only minor adjustments will have to be made to its path, something that should extend the life of the spacecraft.

In front

Over the course of the next 40 days, mission controllers will allow the satellite to gradually drift into the exact orbit needed for it to observe the Earth.

Jacques Louet, Envisat programme manager at the European Space Agency, said there was no injection error to correct and the procedure would use only 10 kilograms of fuel.

The adjustments are being made so that Envisat's data can be compared with that of ERS-2, the European Space Agency's existing Earth-observation satellite.

"We have to phase the two spacecraft for them to observe the same area of the Earth at a half-hour interval," Dr Louet told reporters in Kourou.

Once in phase, the two satellites will pass over the same point on the Earth exactly 30 minutes after each other, with Envisat making the lead pass.

Fine tuning

The spacecraft's work is only just beginning. Over the next few days, its giant antenna will be deployed and a second antenna that allows it to communicate with other satellites will be switched on.

Within the next week, payload communications will be activated, followed by its scientific instruments. Among the first will be Meris (Medium Resolution Imaging Spectrometer), the sensor that will allow Envisat to observe the oceans.

Sensitive atmospheric instruments such as AATSR (Advanced Along-Track Scanning Radiometer) will be the last to be deployed.

Envisat will then begin its task of monitoring the planet for signs of climate change and pollution and to record the state of the world's forests.

The BBC's Sue Nelson
"It is the size of a double decker bus"
Jean-Marie Luton, Arianespace
"We must provide Europe with the instruments to play a role at a world level"
Dr Jonathan Bamber, Envisat scientist
Envisat has better instruments than the satellites that have gone before it





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