Since Nasa’s mission to Mars got under way on August 6, the Curiously Rover has beamed some astonishing images back to Earth that have left scientists and amateur star-gazers alike scratching their heads and envisioning UFOs.

But even seasoned alien watchers were puzzled when the rover making its way through the Red Planet send back the image of what appeared to be a fossilized human finger.

YouTube user StephenHannardADGUK, part of a group called Alien Disclosure UK, who had caused a stir on the Internet last week after pointing out white ‘flying objects’ zooming across the Martian sky called attention to a collection of ‘mysterious’ items he spotted in a video from Gale Crater.