An enormous impact crater has been discovered under a half mile-thick ice sheet in Greenland and the experts say the impact could have happened as recently as 12,000 years ago.
What looks like a bowl-shaped crater appears to be the result of a mile wide, 10 billion tonne iron meteorite that experts say hit Greenland at a speed of 12 miles per second, releasing 47 million times the energy of nuclear bomb dropped on Hiroshima in 1945.