'U.S. astronaut, Buzz Aldrin, the second man to walk on the Moon, alluded to a monolith detected on Mars' moon Phobos. Speaking on a U.S. cable television channel he said: "We should visit the moons of Mars. There's a monolith there - a very unusual structure on this little potato shaped object that goes around Mars once every seven hours. 'When people find out about that they are going to say, "Who put that there? Who put that there?" '

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