Boulder Movement (IMAGE) University of Maryland Caption A 30-meter-wide, 12,800-ton boulder was found to have moved 140 meters in the Khonsu region of Comet 67P/Churyumov-Gerasimenko in the lead up to perihelion in August 2015, when the comet's activity was at its highest. In both images, an arrow points to the boulder; in the right-hand image, the dotted circle outlines the original location of the boulder for reference. The images were taken by Rosetta's OSIRIS camera on May 2, 2015 (left) and Feb. 7, 2016 (right). Credit ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA 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.