In 2012, NASA landed the rover Curiosity in the Gale crater on Mars because the crater was thought by many scientists to be the site of an ancient lake on Mars more than 3 billion years ago. Since that time, the rover has been driving along, carrying out geological analyses with its suite of instruments for over 3,190 sols (martian days, equivalent to 3278 earth days). After analyzing the data, researchers from Department of Earth Sciences, the Faculty of Science at HKU, have proposed that the sediments measured by the rover during most of the mission did not actually form in a lake.
Click here for original story, NASA rover has been exploring surface sediments, not lake deposits, for last eight years: study
Source: Phys.org