Gale Crater with Lake (IMAGE) University of Copenhagen - Niels Bohr Institute Caption The researchers believe that Gale Crater was a large lake between 3.5 and 2.7 billion years ago. Mount Sharp, which is now an approximately five kilometer tall mountain in the middle of the crater, was probably formed by deposits from the crater and the surrounding area. Credit (Credit: NASA/JPL/Caltech/ESA/DLR/MSSS) Usage Restrictions (Credit: NASA/JPL/Caltech/ESA/DLR/MSSS) 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.