NASA's rover Curiosity made two significant discoveries recently in the Gale crater on Mars.<br />According to NASA, the rover found evidence of organic matter inside a mud-rock dating back 3.5 billion years.<br />The Curiosity rover touched down inside the crater years ago because NASA thought it was an ancient lake bed, where life may have formed.<br />Although Curiosity hasn't found evidence of life yet, the rover has found evidence that Mars was once a habitable environment. <br />
