Site of Asteroid Impact Changed the History of Life (image) Tohoku University Share Print E-Mail Caption Fig. 1) Mass extinction only occurred when the asteroid having 9-km diameter hit the orange areas. Credit Kunio Kaiho Usage Restrictions Credit:Kunio Kaiho Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.