scientist say they have made an stupefying discovery of a bombastic meteorite crater in Greenland – the first ever learn there , and the first ever recover under an chicken feed sheet .
Published in the journalScience advance , a squad led by Kurt Kjaer from the University of Copenhagen in Denmark described how they find what ’s think to be an impact crater concealing under 900 metre ( 3,000 foot ) of ice beneath the Hiawatha Glacier in northwest Greenland .
The crater is thought to be 31 km ( 19 miles ) astray , make it one of the 25 largest impact craters on Earth . The aim that caused it was likely an smoothing iron asteroid about 1.5 kilometers ( 0.9 miles ) across , the sizing of a city , weighing 12 billion t ( 13.2 billion tons ) . It ’s think to have run into Greenland anywhere from 12,000 to 2 million years ago at a speed of about 20 kilometers ( 12 miles ) per second .
“ It was hiding in plain deal , ” Kjaer told IFLScience . “ How often do you go out in the world and make a find like this ? It ’s mind - boggling . ”
The crater was first distinguish in 2015 , when radar was used to map the Greenland ice sheet . Looking at the map , Kjaer and his squad point out there was a large depression towards the northwestern United States of the island .
In May 2016 , a German research plane flee back over the domain , take young chalk radar images . These started to show that the researchers were right – there was a circular feature 100 of metre under the ice with a lip around it .
In summer 2016 , Kjaer locomote to the site to take sampling . He rule that meltwater was leaking from the ice , containing material come from the crater . study samples of this water , his team found the “ smoking guns ” of quartz glass grain that had been affected by the shock of the shock .
Perhaps most unmistakably of all , the team bring in a 20 - long ton clod of meteorite that had been sitting in the University of Copenhagen ’s Centre for GeoGenetics – collected from Greenland in 1963 – was most likely a glob of this impactor . And other man found in this area may have add up from the shock , too .
Some major enquiry about the wallop remain , however , include its eld . The squad have date it to thePleistocene era(2.6 million to 11,700 years ago ) , saying it must have impact after ice began to cover Greenland 3 million years ago and after the nearby bedrock took shape 2 million age ago , but before the last ice age ended at the end of the Pleistocene .
The other question is what effect this wallop had on the planet . enceinte impacts like these can have striking effect on Earth ’s clime , and this may have been no elision , immerse itself 7 kilometers ( 4 miles ) into the chicken feed . This event could have dissolve and evaporated huge amounts of ice , let go considerable amount of money of pee into the North Atlantic .
Kjaer noted that this impingement could even have had a function to play in theYounger Dryas – a period 12,900 to 11,700 years ago when temperature in the Northern Hemisphere mysteriously dropped to glacial levels .
In their paper the squad also said there could be more discoveries to make in this arena , with “ one of the most promising region , ” being southwest of this volcanic crater . “ We are come across a hidden landscape that is part to emerge , ” said Kjaer . “ And there are surely more discovery to be made . ”
One of the next primal steps will be form out how honest-to-god the volcanic crater is . This could be done by look for debris eject from the impact nearby . And if we can line up that out , we might bring out what gist this with child asteroid had on Earth .
