People living in southern Germany during Roman times may have witnessed a comet impact 5,000 times more destructive than the Hiroshima atom bomb, researchers say.Scientists believe a field of craters around Lake Chiemsee, in south-east Bavaria, was caused by fragments of a huge comet that broke up in the Earth’s atmosphere.Celtic artefacts found at the site, including a number of coins, appear to have been strongly heated on one side.This discovery, together with evidence from ancient tree rings and Roman reports of “stones falling from the sky”, has led researchers to conclude that the impact happened in about 200BC.However the claim still needs to be verified by other experts.The crater field was uncovered after amateur archaeologists working in the area found pieces of metal containing unusual minerals.A team of geologists led by Kord Ernston, from the University of Wurzburg in Germany, went to the site and discovered evidence of a cataclysm that would have left the region devastated for decades.Not only would trees and homes have been flattened for many miles by the blast, but the local climate would have changed for years afterwards.Tree rings show that vegetation growth slowed down in around 207BC, possibly because of the “nuclear winter” effect of dust blotting out the sun.More than 80 craters were found in an elliptical area 36 miles long and 17 wide, ranging in size from 10 to 1,215 feet across. The largest, filled with water, now formed Lake Tuttensee.Around the site the team found clues that suggested an impact from space, including rock heated into glass and minerals associated with meteorites.The most likely cause was a low-density comet, 0.7 miles (1.1 kilometres) wide, that broke up at an altitude of 43 miles and fell in pieces to Earth, the scientists reported in Astronomy Magazine.
View: Full Article | Source: The Scotsman
