TREAD MARKS IN SIMULATED LUNAR REGOLITH (IMAGE) Southwest Research Institute Caption A robotic rover created tread marks in simulated lunar regolith, or Moon soil, as part of a research project using SwRI’s Ranger machine vision tool for lunar rover navigation. Credit Southwest Research Institute Usage Restrictions Images/Videos may be used by the public for educational and informational purposes only. License Original 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.