Buzz Aldrin, the second man to set foot on the moon, said he glimpsed an unidentified flying object during the Apollo 11 flight.
The astronaut also said the first humans to set foot on Mars should never return to earth during a Reddit 'ask me anything' question and answer session to celebrate the moon landing's upcoming 45th anniversary.
Mr Aldrin, 84, however was reluctant to describe the sighting as an extraterrestrial craft, even though he does believe there are other life forms in space.
“I observed a light out the window that appeared to be moving alongside us,” he said.
“There were many explanations of what that could be, other than another spacecraft from another country or another world - it was either the rocket we had separated from, or the four panels that moved away when we extracted the lander from the rocket and we were nose to nose with the two spacecraft.
“So in the close vicinity, moving away, were four panels. And I feel absolutely convinced that we were looking at the sun reflected off of one of these panels.
“Which one? I don't know. So technically, the definition could be ‘unidentified’."
When Mr Aldrin disclosed the sighting, his remarks triggered accusations of a cover-up from those who believed in UFO’s.
But he remained unapologetic about his caution. “Extraordinary observations require extraordinary evidence,” he added.
“There may be aliens in our Milky Way galaxy, and there are billions of other galaxies. The probability is almost certain that there is life somewhere in space.
“It was not that remarkable, that special, that unusual, that life here on earth evolved gradually, slowly, to where we are today.”
With Mars One, a private sector company, pressing ahead with its plans to send people to the Red Planet, Mr Aldrin said those who go should plan staying there for the rest of their lives.
“I have considered whether a landing on Mars could be done by the private sector,” he continued.
“It conflicts with my very strong idea, concept, conviction, that the first human beings to land on Mars should not come back to Earth.”
The Telegraph, UK
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