LONDON: British scientists are toying with the possibility that their missing baby, Beagle 2, might have tumbled down the slopes of an impact crater on Mars.

The region of Isidis Planitia, just north of the Martian equator, was selected as a landing site because it seemed to offer a compromise between safety and interesting geology in the search for life. But a high resolution satellite image of the final target area has revealed a 1km-wide crater in the centre.

Long before the June launch, scientists had selected a 480km by 300km area as the landing site. But only after Beagle had been launched from the mothership Mars Express on December 19 could the mission controllers narrow this down to an area 70km long and 10km wide.

By Monday they had their first satellite picture of the landing strip, taken by an older Nasa spacecraft, Mars Global Surveyor, 20 minutes after Beagle should have landed.

“Right at the centre of the ellipse that we were aiming at is a 1km crater,” said Colin Pillinger, the lead scientist on the mission. “We’d have to be incredibly accurate and also incredibly unlucky if it went down this crater. Which of course would not be good news.

“One would not want to go into a crater; one would not want to bounce around it. There is going to be impact debris around it - which means more rocks — and if we get to the bottom of a crater we reduce our attempts to be able to signal out of it.” He put the probability of landing in the crater at “a little more than one in 200”.

Beagle could also have burned up when it entered the Martian atmosphere at 12,000mph or smashed when it landed on the rocky surface, but the scientists are concentrating on the challenges they can meet rather than the ones they cannot. The best hope is that Beagle is alive and well but simply unable to get a message home.

By yesterday morning the craft had missed five programmed encounters with the Nasa orbiter Mars Odyssey. It has been programmed to keep trying until New Year’s Eve.

Radio telescopes in Manchester, the Netherlands and California have listened, without success, for the faint squeak of its signal, and mission controllers at Leicester space centre have been trying to talk to their tiny truant — a package of state-of-the-art instruments in a container the size of a home barbecue — across 100 million miles of space.

Beagle’s computer contains instructions to switch on and send a signal as the Odyssey passes overhead and then switch off again to conserve its battery. The timing could have faltered somehow, so scientists hope to reset the clock to the correct time.

“We must make sure that whatever we do we don’t make the situation worse,” said Mark Sims of the University of Leicester.

There are other options. One is to wait until the mothership Mars Express begins its orbit around Mars on Sunday, and hope that Beagle will have begun searching for someone to talk to by then.

“There are some worst case scenarios,” Dr Sims said. “Maybe the receiver has failed or the transmitter has failed, in which case that is almost certainly the end of mission.

But at the moment our assumption is that Beagle 2 is on the surface, it is turning its receiver on — maybe not at the correct time - and that may explain entirely why we cannot talk to Beagle 2.”

Nobody, so far, has talked seriously of failure. The science minister, Lord Sainsbury, yesterday described the exploration of Mars and the search for extraterrestrial life as a priority, and promised government support for a Beagle 3 mission using robot technology in the next decade.

“While we are disappointed that things have not gone according to plan, we are determined that the search should go on,” he said.—Dawn/The Guardian News Service.