Impact Experiments - Water on Early Mars

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, which was observed by the Mars rover Spirit, created when a volcano erupted nearly 3.5 billion years ago. The study provides more evidence that early Mars was saturated with water and that its atmosphere was considerably thicker - at least 20 times more dense - than it is today.