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Breaking news: Hello Earth, can you hear me? Comet lander Philae wakes up from 7-month hibernation, says European Space Agency

The European Space Agency revealed it communicated for a minute
Philae landed on comet 67P on 12 November but bounced twice
Scientists have been trying to locate it ever since it went into hibernation

By Kate Pickles and Jonathan O'Callaghan for MailOnline

Published: 07:20 EST, 14 June 2015 | Updated: 07:37 EST, 14 June 2015

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The comet lander Philae has awakened from a seven-month hibernation and communicated with Earth for more than a minute, scientists have revealed.

The probe became the first spacecraft to land on a comet when it touched down on the icy surface of 67P/Churyumov-Gerasimenko in November last year.

It went into hibernation 60 hours after the historic landing when its batteries depleted, after sending images to Earth.

Awake: The Philae Lander has awoken after seven months in hibernation, scientists revealed from its Twitter account

The 'ice harpoons' on the European Space Agency's Philae probe failed to fire into the ground, causing it to bounce twice above the surface before coming to rest.

Since then, scientists have been trying to find the probe through a variety of methods.

The German Aerospace Center, which operates Philae, said that the probe resumed communication at 20.28 pm on Saturday, sending about 300 packages of data to Earth via its mother ship Rosetta, which is orbiting the comet.

'Philae is doing very well,' project manager Stephan Ulamec said.

Awake: The European Space Agency has revealed Philae has made contact for the first time in seven months

One of the methods scientists tried was to use radio signals sent between Philae and Rosetta as part of the Consert (Comet Nucleus Sounding Experiment by Radiowave Transmission) experiment.

ROSETTA: THE STORY SO FAR

The Rosetta probe, which was carrying Philae, launched into space in 2004, using the gravity of Earth and Mars to slingshot its way towards comet 67P/Churyumov-Gerasimenko.

It chased the comet through space for more than ten years, entering orbit in August 2014.

After a four-billion-mile (6.4 billion km) journey, the probe then successfully released the Philae lander from its grip to land on the comet on 12 November 2014, travelling at 3.3ft (one metre) a second relative to the comet.

But when it first made contact with the surface it failed to fire harpoons that would have kept it attached to the comet.

This resulted in it bouncing to a height of 0.62 miles (1km) above the comet before again landing on the surface. It then bounced again, but to a much lower altitude.

Philae managed to perform more than 90 per cent of its goals before running out of power. Rosetta, meanwhile, is continuing to orbit and study the comet.

From data collected by the two probes, Esa said that water on the comet was different to that on Earth - suggesting water on our world came from an asteroid, not a comet.

This enabled scientists to create an ellipse about 52 by 525ft (16 by 160 metres) in size where they expected the lander to be.

Investigating an area nearby, the science team found a candidate that can be seen in images taken by Rosetta on 12 and 13 December 2014, a month after the landing.

But, crucially, the bright object does not appear in an image taken on 22 October - three weeks before the landing.

The former images were taken from a distance of five miles (8km) above the surface, and the latter images were 11 miles (18km).

Taking an image on both 12 and 13 December ruled out the possibility that this was simply a naturally occurring phenomenon such as a glint of sunlight on a rock spotted by Rosetta.

Philippe Lamy, a member of Rosetta’s Osiris team at the Laboratoire d’Astrophysique de Marseille, said it was ‘a good candidate for the lander’ on Esa's Rosetta blog.

He added: ‘This bright spot is visible on two different images taken in December 2014, clearly indicating that it is a real feature on the surface of the comet, not a detector artefact or moving foreground dust speck.’

Finding the lander has important scientific implications, most notably for the Consert experiment.

This uses signals sent between Philae and Rosetta through the comet to map the interior of the structure, but without knowing Philae’s position the measurements are less precise.

‘Accurately locating the lander is of great scientific value, in particular for the joint orbiter and lander Consert experiment to get the best assessment of the interior structure of the comet nucleus,’ said Matt Taylor, Esa’s Rosetta project scientist.

Philae search! Zooming in on promising candidate on Rosetta