THE fate of Britain's Beagle 2 probe looked uncertain today after scientists failed to receive its call sign from the surface of Mars.

ANXIOUS WAIT AS BEAGLE FAILS TO SEND MESSAGE FROM MARS

By John von Radowitz, Science Correspondent, PA News

The fate of Britain's Beagle 2 probe looked uncertain today after scientists failed to receive its call sign from the surface of Mars.

Beagle 2, which has travelled 250 million miles to search for signs of life on the Red Planet, should have landed at 2.54am, UK time.

Scientists involved in the project waited anxiously in London today for a message telling them "the Beagle has landed".

But the signal, in the form of a nine-note tune composed by members of the pop group Blur, never arrived.

Mission controllers must now wait until between about 10pm and 12.30 tonight for their next chance to check if the tiny craft has survived.

Members of the Beagle team, plus a number of guests, stayed up all night for news of the probe at the Open University's offices in Camden, north London.

The project's chief scientist, Professor Colin Pillinger, told waiting reporters: "I'm afraid it's a bit disappointing, but it's not the end of the world. Please don't go away from here believing we've lost the spacecraft.'

On Friday Beagle 2 separated from its Mars Express mother ship, and appeared to be on a perfect course for a Christmas Day landing.

But first it had to endure a perilous descent through the Martian atmosphere, slowing from 12,500mph to 36mph in under eight minutes.

The craft's heat shield, two parachutes, and protective inflatable gas bags all had to work without a hitch for the mission to succeed.

Then Beagle 2 had to make contact with Nasa's Mars Odyssey spacecraft, which has been orbiting the planet since 2001. Odyssey is being used as a relay station until Mars Express is ready to take over communications.

Scientists had hoped to receive the call-sign shortly after 6am, UK time. As well as the Blur tune, it was to have contained the first image of Mars taken by Beagle 2's camera.

Tension mounted at the Open University centre as Prof Pillinger waited on an open phone line to Odyssey's controllers at Nasa's Jet Propulsion Laboratory in Pasadena, California.

In front of him was a bank of 10 television cameras.

At 6.10am he announced: "Unfortunately we don't have any Beagle telemetry in the signal.'

Earlier, the Open University planetary scientist who devoted six years of his life to Beagle 2 was grinning broadly as he shared a joke with Palab Ghosh, the BBC's science correspondent.

Now the smile had gone, but he looked impassive rather than disappointed.

He added: "We've just gone into extra time. There's a long way to go.'

Later tonight scientists will try using the giant radio telescope at Jodrell Bank, Cheshire, to catch a faint carrier signal direct from Beagle 2's own transmitter.

They have to wait until the right part of Mars is facing the Earth. The signal, no stronger than that from a mobile phone and containing no data, could arrive between about 10pm and 12.30.

The next opportunity to catch a relayed message from Mars Odyssey will not be until tomorrow evening.

Prof Pillinger said at least 14 possible Odyssey contacts were programmed into Beagle 2's computer. Since the spacecraft's orbit varied slightly, it was still possible that a later one might put Odyssey in the right position to "lock on to' Beagle 2.

Even if there is no contact via Mars Odyssey, there could still be a slim chance of getting the signal when Mars Express is up and running in about 10 days' time. Unlike Odyssey, Mars Express is tailor-made to communicate with the probe.

Beagle 2 is on a 180-day mission to test soil, rock and air samples for signs of past or present life on Mars.

The craft, weighing less than 155lb and no bigger than a motorbike wheel, was designed to bounce like a beachball before cutting free from its gas bags and dropping to the surface.

Then it was supposed to open up like a pocket-watch to expose its solar panels and instruments, which include a robot arm for gathering samples.

Prof Pillinger said Beagle 2 may have landed in the wrong area, its antenna could be pointing the wrong way, or its signalling timer could be at fault. Alternatively, there could be a mis-match in its system link with Odyssey, which had not been tested.

Any of these situations could have prevented Odyssey passing on its signal. But the other scenario was that the probe had been destroyed.

Most other scientists accompanying Prof Pillinger remained hopeful.

Open University geologist Dr Dave Rothery, who helped in the selection of the landing site, said: "Naturally I am disappointed, but it's early days. It was always on the cards that this might happen.

"There's such a long chain of events and establishing communications is just one of them. Odyssey was not designed and built to be the transmitter for Beagle 2.'

He said the landing site was carefully chosen to minimise natural hazards.

Beagle 2 was aimed at Isidis Planitia, a low-lying plain strewn with rocks, mostly no bigger than a house brick.

Scientists believe the region was once covered in water and may have harboured life.

Dr Rothery said it was possible Beagle 2 had landed tilted on its side on the edge of a crater.

"There are small craters in that area, you can never avoid them completely,' he said. "If Beagle came to rest at a tilt, its antenna might not have been in the right position to pick up Mars Odyssey. But it might be OK with a later orbit.'

Blur's bass player Alex James, who had stayed up with the scientists, was upbeat.

He said: "It would have been nice if we had heard it had landed but it's far away and very alone. Maybe they're picking the music up on Pluto.

"In a way it's already been a massive success just for free enterprise and British balls and brilliance.

"This is pure theatre. We've got the world's media here. Now it gets better, we get the big toys out - Jodrell Bank.'

The band's drummer David Rowntree, who has shared James's interest in astronomy since they were at school together, said: "It would have been very nice to round the morning off with finding Beagle, but unfortunately finding spacecraft that you've thrown to distant planets is not easy.

"I'm quietly confident. We've made it this far and there's no reason we shouldn't go the whole way.'

The £140 million mission began in June when a Russian rocket launched Mars Express into space from the Baikonur spaceport in Kazakhstan.

In October the spacecraft's navigation system was temporarily blinded by radiation from a powerful solar flare, but it survived.

A Japanese mission to Mars, Nozomi, had to be abandoned after the probe developed electrical problems, caused by the same solar storm.

Controllers steered the craft away from the planet to prevent it crashing on to the surface.

Beagle 2 arrived ahead of two golf-cart-sized Nasa rovers, Spirit and Opportunity, due to reach Mars on January 4 and 24.

Both will spend three months carrying out geological surveys, but neither is equipped to search for direct signs of life.

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