Mars Impact Experiment (VIDEO) Georgia Institute of Technology This video is under embargo. Please login to access this video. To view this video please enable JavaScript, and consider upgrading to a web browser that supports HTML5 video Caption Georgia Tech assistant professor Josef Dufek created bomb sags in his lab by propelling particles into sand beds. The demonstration is used to study a sag on the Martian surface, created when a volcano erupted nearly 3.5 billion years ago. The study provides more evidence of water on early Mars. Credit Georgia Institute of Technology 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.