Top CU-Boulder Science Stories (IMAGE) University of Colorado at Boulder Caption A 2009 CU-Boulder study on how bombardment of Earth by asteroids 3.9 billion years ago may have enhanced early life was named one of top 100 science stories of 2009 by Discover Magazine. Credit Illustration courtesy NASA/JPL Usage Restrictions None License Licensed content 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.