Prehistoric Crash Sites

It is estimated that during the past 3.5 billion years, more than 80 bodies bigger than the dinosaur-killing asteroid, which crashed in the Yucatan peninsula 66 million years ago, have landed on Earth, creating craters. But very few of these are present now because tectonic processes and weathering destroy them. As per a first-of-its-kind quantitative estimate, only four such craters could have survived till the present age. Three craters of diameter greater than 170 km have already been found. 


Down To Earth, June, 2014