THE mystery of the rocky Mars "monolith" which set tongues wagging around the world when it appeared to show evidence there was once life on the Red Planet has been solved - and alien hopefuls won't be impressed

Captured by a high-resolution camera on the Mars Reconnaissance Orbiter last July, it resembled the black monolith from Stanley Kubrick's movie 2001: A Space Odyssey.



But Britain's Daily Mail newspaper reveals scientists at the University of Arizona, which captured the original image, insist it's just a broken boulder.



University spokesman Yisrael Spinoza said: "It would be unwise to refer to it as a 'monolith' or 'structure' because that implies something artificial, like it was put there by someone for example.



"In reality it's more likely that this boulder has been created by breaking away from the bedrock to create a rectangular-shaped feature."



Scientist Alfred McEwen added: "There are lots of rectangular boulders on Earth and Mars and other planets.



"Layering from rock deposition combined with tectonic fractures creates right-angle planes of weakness such that rectangular blocks tend to weather out and separate from the bedrock."