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Sensors in the feet of Rosetta's lander Philae have recorded the sound of touchdown as it first came into contact with Comet 67P/Churyumov-Gerasimenko. 

The instrument, called SESAME-CASSE, was turned on during the descent.

It clearly registered the first touchdown as Philae came into contact with the comet, in the form of vibrations detected in the soles of the lander's feet.

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Vibrations detected in the soles of the lander's feet were recorded to create the audio of the 'crunch' as the lander hit the comet's surface for the first time.

The European Space Agency confirmed the recording was 'real' audio.

'Note that this is an actual sound file; i.e. it is a recording of mechanical vibrations at acoustic frequencies,' it said.

'No modification was necessary except for some technical adjustments (e.g. the .wav format requires amplitude normalisation). 

'Actual frequency content and duration are unchanged.'

SESAME is the lander's Surface Electrical Sounding and Acoustic Monitoring Experiment, and comprises three suites of instruments:

Klaus Seidensticker from the DLR Institute of Planetary Research says: 'Our data record the first touchdown and show that Philae's feet first penetrated a soft surface layer – possibly a dust layer – several centimetres thick until they hit a hard surface – probably a sintered ice-dust layer – a few milliseconds later.'

Data from the SESAME-DIM instrument meanwhile suggest that current cometary activity at the final landing site is low, while preliminary data from SESAME-PP are consistent with a large amount of water ice under the lander. 

Combined with additional data from other instruments, the goal is to derive mechanical properties of the comet. 

However, first impressions already suggest that the surface of 67P/C-G is significantly structured, mixing soft and hard aspects.

Klaus adds: 'At the moment, we are also supporting the effort to reconstruct the flight path of the lander after first touchdown, collecting all available data across the various instruments. 

This is important for SESAME, especially CASSE, as we need to know the speed, impact angle, and rotation rate before the first touchdown, but also the final landing place.'

Rosetta's data has already revealed important information about the comet. 

Using the Rosetta Orbiter Spectrometer for Ion and Neutral Analysis - or Rosina - the spacecraft 'sniffed' the comet's atmosphere as it remained in orbit and analysed its composition.

It found that water in the comet's atmosphere had a different ratio of deuterium-to-hydrogen than water on Earth.

Illustrated here are the various scientific instruments on the Philae lander that were used to study the comet when attached to the surface. SESAME is the lander's Surface Electrical Sounding and Acoustic Monitoring Experiment, and comprises three suites of instruments:

Data from an instrument on the Rosetta orbiter has suggested that asteroids, not comets, are the origin of water on Earth. It is hoped that the findings can be confirmed by the Philae lander on the surface (artist's illustration shown)

This may be the final nail in the coffin for the theory that comets brought water to Earth - and it may have finally proven that we have asteroids to thank for allowing life on our planet to thrive.   

All of the deuterium and hydrogen in the universe was made just after the Big Bang about 13.7 billion years ago, making their ratio important.

The ratio of the two in water varies from location to location depending on when the water formed, and so by comparing the ratio found in extra-terrestrial objects to Earth's water, it's hoped the ration can be found.

Water molecules are thought to have been part of the disc of dust and gas that ultimately formed the sun and its planets, but Earth began as a hot molten rock that would have been inhospitable to water early in its life up to 3.8 billion years ago. 

The preferred theory is that an asteroid or a comet - both of which have ice in various quantities - crashed to Earth and delivered water when our planet was a more moderate temperature.

In November 2010, Nasa's Deep Impact spacecraft flew past a comet called Hartley 2 and collected samples that indicated its water had a similar composition to Earth, but in recent years the asteroid theory has been favoured.

And now the latest results from Rosetta could confirm an asteroids as our origin.

The initial findings were hinted at by Rosina principle investigator Dr Kathrin Altwegg of the University of Bern, reports Science.

'Altwegg says the result for 67P could make asteroids the primary suspect again, writes Eric Hand.

Further studies of the data will be needed to confirm the finding and they may be hiding in the scientific data returned by the Philae lander, particularly its Ptolemy instrument.

Ptolemy is a gas analyser that was used to measure ratios of isotopes such as hydrogen, carbon and oxygen. 

The news comes as the Philae team revealed some of the first science that had been returned by the lander yesterday. 

Esa released early scientific data from the Philae lander, revealing not only organic molecules on comet 67P but also the structure and composition of the comet as well.

This was one of the first pictures return by Philae from the surface of comet 67P. Yesterday scientists said they are 'very confident' it will 'wake up' when the comet moves into an orbit where more sunlight hits is solar panels in a few months

The data returned from the Cosac (Cometary Sampling and Composition Experiment) instrument showed that the comet has an organic compound containing carbon - an important progenitor for life as we know it.

It was also announced that the surface of the comet was far harder than researchers had expected. Before Philae's battery died they were also able to form a 3D mapping mission of the comet's interior using the Rosetta spacecraft. 

Rosetta's lander captivated the world by landing on the surface of a comet last week, but went into hibernation mode late on Friday when its primary battery ran out of power.

However, scientists also said they are 'very confident' it will wake up again when the comet moves into an orbit where more sunlight hits its solar panels in a few months - and one Nasa expert even thinks a jet of gas from the comet could move it sooner.

Further analysis of the various scientific data returned by Philae will be needed before any firm  conclusions can be drawn.

But the tentative discovery of organic molecules by Cosac is certainly promising.

It's also unclear to what extent Philae's drill was able to penetrate the surface, and whether or not it was able to get a sample back to the lander for analysis - however there have been some suggestions that it failed to do so. 

Before going into hibernation at 00:36 GMT on 15 November 2014, the Philae lander was able to conduct some work using power supplied by its primary battery. 

With its 10 instruments, the mini laboratory sniffed the atmosphere, drilled, hammered and studied Comet 67P/ Churyumov-Gerasimenko while over 500 million kilometres from Earth. 

It was controlled and monitored from the German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt; DLR) Lander Control Center (LCC). Now, the complicated data analysis begins.

DLR's Scientific Director for the project, Ekkehard Kührt, said the team were pleased with the results.

This incredible series of images shows Philae first's bounce on the surface of comet 67P at the initial landing site, named Agilkia. The times are in GMT. The first four images show the moments leading up to the first landing on the surface, and the final image in the top right shows the direction the probe went in after its first bounce - and scientists are hoping to spot its final resting place in later images

'We have collected a great deal of valuable data, which could only have been acquired through direct contact with the comet,' he said.

'Together with the measurements performed by the Rosetta orbiter, we are well on our way to achieving a greater understanding of comets. Their surface properties appear to be quite different than was previously thought.'  

Stephan Ulamec believes it is probable that in the spring of 2015, the DLR LCC will once again communicate with Philae and receive data about how the lander is faring on Comet 67P/Churyumov-Gerasimenko. 

In the summer of 2015, it might be possible that temperatures on the comet will allow Philae's battery to be recharged. 'The orbiter will continue with its overflights to receive any signals from the lander once Philae wakes up from hibernation.' 

This incredible image shows the moment the Philae lander bounced off the surface for the first time, on its way to a height of 0.62 miles (1km), before returning to the surface of the comet and bouncing again

Ullanec confirmed the lander was able to send all of its data back to Earth before it 'died' - and celebrated with champagne as the rover's battery power slowly ebbed away.

'Philae has fallen into 'idle mode' - a possibly long silence. In this mode, all instruments and most systems on board are shut down,' the European Space Agency said on its blog in a post entitled Our Lander's Asleep.

The lander's Twitter feed broke the news of its demise, saying: 'I'm feeling a bit tired, did you get all my data? I might take a nap…' - but then added 'I did it! I became the first spacecraft to land on a comet & study it! But it's not over yet…' 

Europe makes space history as Philae probe lands on comet

They also revealed they had spotted the lander's first landing site, which was captured in images from Rosetta - but still were not sure where it had ended up after two more 'bounces'.

'The rotation of the lander's body could result in more power if one of the larger solar panels can catch the illumination that is falling on the smaller,' said Esa's Mark McCaughrean, senior science advisor.

'All things being equal, the same amount of sunlight falling on a larger panel should result in more power being generated.' 

Philae was thought to be partially in darkness beneath a cliff and, crucially, its largest solar panel was not receiving any sunlight.

This means its secondary battery could not be properly charged unless it was rotated after its primary battery ran out of power - which scientists managed to perform before the main battery died. 

The probe landed on the comet at around 3.30pm GMT on Wednesday but then bounced twice - first to a height of 0.62 miles (1km) and then to a much lower height of 65ft (20 metres) before coming to rest.

It is also thought to be about 0.62 miles (1km) from its intended landing site. 

Scientists described the ground as being more like a 'trampoline' than rock, owing to its soft and powdery texture, which may have caused the unsteady landing of the probe. 

The final approach: This image shows comet 67P/CG from a distance of approximately 1.8 miles (3km) from the surface. Philae is now thought to be on the surface but its exact orientation is unknown. It bounced twice before coming to rest

Rosetta has chased comet 67P/Churyumov–Gerasimenko through space for more than ten years in what has been described as 'the sexiest, most fantastic mission ever'

Much of the equipment aboard the lander was switched on for the first time after lying dormant during the ten-year journey.

Klim Churyumov, one of the Ukrainians who discovered the comet 45 years ago and named it, said from mission control in Darmstadt, Germany: 'We saw the first light from this comet in 1969, now we are landing on it. It is a fantastic, outstanding event, the first like it in human civilization.'

Ptolemy, a British-built laboratory the size of a shoebox, will be used to analyse the composition of samples from the 4.5 billion-year-old comet.

Scientists hope the £1 billion ($1.6 billion) project will solve some of the greatest puzzles in science - including the origins of life on Earth.

Open University Professor Ian Wright, who helped create Ptolemy, said: 'The idea that comets may have brought the building blocks of life to Earth is one of the reasons why we want to study them.'

Professor Stanley Cowley, planetary scientist at the University of Leicester, added: 'It is an interesting relic from that otherwise inaccessible epoch.' 

'It's complicated to land on a comet, and complicated to understand what has happened during this landing,' said Dr Stefan Ulamec, Philae Lander Manager.