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Ground control bids farewell to Philae comet lander Ground control bids farewell to Philae comet lander
(35 minutes later)
Ground controllers say it is time to give up hope of ever hearing again from the comet lander Philae.Ground controllers say it is time to give up hope of ever hearing again from the comet lander Philae.
The European Space Agency's Rosetta mission dropped the robot onto Comet 67P in November 2014.The European Space Agency's Rosetta mission dropped the robot onto Comet 67P in November 2014.
But after a troubled landing and 60 hours of operation, there has largely been radio silence from Philae.But after a troubled landing and 60 hours of operation, there has largely been radio silence from Philae.
The German Aerospace Center (DLR), which led the consortium behind Philae, said the lander is probably now covered in dust and too cold to function.The German Aerospace Center (DLR), which led the consortium behind Philae, said the lander is probably now covered in dust and too cold to function.
"Unfortunately, the probability of Philae re-establishing contact with our team at the DLR Lander Control Center is almost zero, and we will no longer be sending any commands," said Stephan Ulamec, the lander's project manager at DLR."Unfortunately, the probability of Philae re-establishing contact with our team at the DLR Lander Control Center is almost zero, and we will no longer be sending any commands," said Stephan Ulamec, the lander's project manager at DLR.
The probe's historic landing famously happened several times in succession - with its first bounce looping nearly 1km back from the comet's surface and lasting a remarkable 110 minutes.The probe's historic landing famously happened several times in succession - with its first bounce looping nearly 1km back from the comet's surface and lasting a remarkable 110 minutes.
When it finally settled, its precise location was unknown but images and other data suggested it was sitting at an awkward angle, in the shade.When it finally settled, its precise location was unknown but images and other data suggested it was sitting at an awkward angle, in the shade.
That meant Philae's scientific activities were limited to a single charge of its solar-powered batteries.That meant Philae's scientific activities were limited to a single charge of its solar-powered batteries.
On several occasions, attempts to contact Philae - via the Rosetta spacecraft, still orbiting Comet 67P - did receive a response.On several occasions, attempts to contact Philae - via the Rosetta spacecraft, still orbiting Comet 67P - did receive a response.
But the last such contact was on July 9 2015 and the comet is now hurtling into the much colder part of its orbit, plunging to temperatures below -180C at which the lander was never designed to operate.But the last such contact was on July 9 2015 and the comet is now hurtling into the much colder part of its orbit, plunging to temperatures below -180C at which the lander was never designed to operate.
"It would be very surprising if we received a signal now," Dr Ulamec said."It would be very surprising if we received a signal now," Dr Ulamec said.
Science continues
The Rosetta mothership may have a chance to take some final pictures of Philae in the summer, during a series of close fly-bys.The Rosetta mothership may have a chance to take some final pictures of Philae in the summer, during a series of close fly-bys.
Rosetta itself will end its mission when it falls onto the comet in September.Rosetta itself will end its mission when it falls onto the comet in September.
Speaking to BBC Radio 5 Live, Esa's senior science advisor Mark McCaughrean said today's news was sad but inevitable. Speaking to BBC Radio 5 Live, the European Space Agency's senior science advisor Mark McCaughrean said today's news was sad but inevitable.
"It's a sad day, of course. Philae certainly captured the imagination of the world back in 2014. "It's a sad day, of course. Philae certainly captured the imagination around the world back in 2014.
"But all good things come to an end. In fact, if it had landed properly on the surface, it all would have been over last March because Philae would have overheated." "But all good things come to an end. In fact, if it had landed properly on the surface in the first place, it all would have been over last March because Philae would have overheated."
Prof McCaughrean emphasised that the Rosetta orbiter was "still out there doing fantastic science".Prof McCaughrean emphasised that the Rosetta orbiter was "still out there doing fantastic science".