Post by Salem6 on Dec 25, 2003 9:45:27 GMT
Scientists have failed to pick up an expected signal from British-built spacecraft Beagle 2 telling them it has landed safely on Mars.
The £35m probe should have landed at 0254 GMT on Christmas Day after a 400 million kilometre, six-month flight.
Scientists wait for the signal from Beagle 2
Nasa's Mars Odyssey orbiter has since flown over its landing site but failed to detect the expected call sign.
The giant Jodrell Bank telescope, in Cheshire, UK, will come on line at about 2200 GMT to listen for signals.
Scientists are confident that sweep will pick up a signal from Beagle 2 - if it has made it to the planet surface in one piece and is functioning as expected.
If that option fails, the Nasa spacecraft will have a daily chance to pick up the signal until 3 January, when Europe's Mars Express craft - the mother ship now orbiting the planet - begins its mission.
However, if nothing has been received by the end of 26 December, hopes for Beagle 2 will start to fade.
The probe must recharge its batteries on the day it lands or it will not survive the first night on Mars.
Speaking at the Open University's offices in Camden, north London, Beagle's lead scientist, Professor Colin Pillinger, told 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.
"We've just gone into extra time, there's no penalty shoot-out yet," he said.
Mike Healey from Beagle 2's constructor Astrium UK said he had not contemplated a "negative scenario".
"It really should have been able to communicate with Odyssey this morning.
"But it could have landed in the wrong place or it may not have opened successfully, and the aerial may be pointing in the wrong direction."
The landing could have damaged the probe
He also said there was a "small possibility" Beagle 2 was not able to communicate properly with Odyssey, as it had originally been designed to communicate with Mars Express at this stage.
Beagle 2's plunge through the thin atmosphere of Mars, slowed by parachutes and cushioned by airbags, is the most dangerous part of the mission.
The worst case scenario is that Beagle has crashed and is lying in fragments strewn across the Martian surface.
But another member of the Beagle team, Ian Wright from Open University, said there was "no point contemplating that one at the moment".
"There are still plenty of things to try," he said.
Successful orbit
If successful, Beagle 2 will embark on a 180-day mission to search for signs of life.
The one piece of good news early on Christmas morning was Mars Express, in another high-risk manoeuvre, successfully entering into orbit around the planet.
The craft will send back 3-D pictures of the surface and scan for underground water with a powerful radar.
But the historical odds of success for Beagle 2's mission are low. Despite more than 30 missions launched to the Red Planet since the 1960s, only three landers have ever reached the Martian surface successfully.
All of these were costly American missions, unlike Beagle 2, which was put together in record time and on a shoestring budget.
Video:-
The BBC's David Shukman
"Hopes are still being kept alive"news.bbc.co.uk/media/video/39674000/rm/_39674257_beagle08_shukman_vi.ram
The £35m probe should have landed at 0254 GMT on Christmas Day after a 400 million kilometre, six-month flight.
Scientists wait for the signal from Beagle 2
Nasa's Mars Odyssey orbiter has since flown over its landing site but failed to detect the expected call sign.
The giant Jodrell Bank telescope, in Cheshire, UK, will come on line at about 2200 GMT to listen for signals.
Scientists are confident that sweep will pick up a signal from Beagle 2 - if it has made it to the planet surface in one piece and is functioning as expected.
If that option fails, the Nasa spacecraft will have a daily chance to pick up the signal until 3 January, when Europe's Mars Express craft - the mother ship now orbiting the planet - begins its mission.
However, if nothing has been received by the end of 26 December, hopes for Beagle 2 will start to fade.
The probe must recharge its batteries on the day it lands or it will not survive the first night on Mars.
Speaking at the Open University's offices in Camden, north London, Beagle's lead scientist, Professor Colin Pillinger, told 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.
"We've just gone into extra time, there's no penalty shoot-out yet," he said.
Mike Healey from Beagle 2's constructor Astrium UK said he had not contemplated a "negative scenario".
"It really should have been able to communicate with Odyssey this morning.
"But it could have landed in the wrong place or it may not have opened successfully, and the aerial may be pointing in the wrong direction."
The landing could have damaged the probe
He also said there was a "small possibility" Beagle 2 was not able to communicate properly with Odyssey, as it had originally been designed to communicate with Mars Express at this stage.
Beagle 2's plunge through the thin atmosphere of Mars, slowed by parachutes and cushioned by airbags, is the most dangerous part of the mission.
The worst case scenario is that Beagle has crashed and is lying in fragments strewn across the Martian surface.
But another member of the Beagle team, Ian Wright from Open University, said there was "no point contemplating that one at the moment".
"There are still plenty of things to try," he said.
Successful orbit
If successful, Beagle 2 will embark on a 180-day mission to search for signs of life.
The one piece of good news early on Christmas morning was Mars Express, in another high-risk manoeuvre, successfully entering into orbit around the planet.
The craft will send back 3-D pictures of the surface and scan for underground water with a powerful radar.
But the historical odds of success for Beagle 2's mission are low. Despite more than 30 missions launched to the Red Planet since the 1960s, only three landers have ever reached the Martian surface successfully.
All of these were costly American missions, unlike Beagle 2, which was put together in record time and on a shoestring budget.
Video:-
The BBC's David Shukman
"Hopes are still being kept alive"news.bbc.co.uk/media/video/39674000/rm/_39674257_beagle08_shukman_vi.ram