A new study released by NASA reveals that there are large organic molecules on Mars. This data was gathered by the Curiosity rover in Mars's Gale Crater where it found the 3.5B year old molecules. These results don't mean there was life on Mars, but they do show where more advanced missions might possibly find that smoking gun. We'll see how it goes with future missions and hopefully we'll be able to once and for all confirm whether life existed on Mars. Thanks cageymaru. To get firmer answers, researchers will need to get equipment to Mars that’s sensitive enough to detect life’s thumb on the chemical scales. On Earth, life makes more methane and less of the gas ethane than non-living reactions do. If researchers saw this signature on Mars, the case for life would get stronger.