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A giant meteor crater five times the size of Paris has been found half a mile (0.8 km) under the ice in Greenland.


It is one of the largest impact craters on Earth, and suggests a 3,300ft-wide (1,000-metre) object made of iron smashed into our planet during the last Ice Age.


It is believed the resulting explosion threw debris several hundred miles in every direction, reaching as far as modern day Canada.


The 12-billion-tonne meteor landed with the power of 47 million Hiroshima bombs, obliterating all life within a 60-mile (100 km) radius, scientists said.


A 19-mile-wide (30 km) impact crater left by the event remained hidden for at least 12,000 years beneath the Hiawatha Glacier in remote north-west Greenland, although scientists have not categorically dated the event. It could be as long ago as three million years when Greenland's ice sheet had already begun to form.


The crater was identified with data collected between 1997 and 2014, supplemented with more collected in 2016 using an advanced form of radar sounding.


'The two combined made a really strong case for this being an impact-crater site.'


The scars of the meteorite smash have been preserved since then after being buried underneath ice more than a kilometre thick.


It was first discovered in July 2015 when researchers from the Natural History Museum of Denmark, University of Copenhagen, detected a depressed area underneath the glacier while inspecting a new map of its physical features.


A research plane then performed state-of-the-art ice radar measurements which revealed the huge crater in detail.


Professor Kjær added that Inuits had not yet colonised Greenland at the time of the event, so it was unlikely that any humans were affected.


The explosion had a lasting impact because it melted swathes of Greenland's ice sheet, causing a flood of freshwater into the Nares Strait.


Dr Paden said: 'There would have been debris projected into the atmosphere that would affect the climate and the potential for melting a lot of ice.


'A sudden freshwater influx into the Nares Strait between Canada and Greenland that would have affected the ocean flow in that whole region.


'The evidence indicates that the impact probably happened after the Greenland Ice Sheet formed, but the research team is still working on the precise dating.'


Chemical analyses performed at Cardiff University allowed researchers to paint a picture of the type of object capable of causing the amount of destruction.


Work remains to determine with more precision the timing of the meteor impact on Greenland.


Professor Kjaer said: 'The crater is exceptionally well-preserved, and that is surprising, because glacier ice is an incredibly efficient erosive agent that would have quickly removed traces of the impact.


'But that means the crater must be rather young from a geological perspective.


'So far, it has not been possible to date the crater directly, but its condition strongly suggests that it formed after ice began to cover Greenland, so younger than three million years old and possibly as recently as 12,000 years ago - toward the end of the last ice age.'


The findings were published in the journal Science Advances.