Buzz Aldrin, the second man to walk on the Moon, has described seeing a UFO during that 1969 Apollo 11 mission, although denied that it was extraterrestrial.

During a “AMA” question and answer session on the popular website Reddit, the 84-year-old astronaut described seeing “a light out the window what appeared to be moving alongside us”.

However, he was quick to dismiss any idea that the UFO was extraterrestrial in origin, explaining:

“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 4 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 4 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’.”

Aldrin went on to explain that any claims of sightings of extraterrestrials need “extraordinary evidence”, but he said that life on other planets somewhere in the universe is almost “certain”, saying:

“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. “But the distances involved in where some evidence of life may be, they may be hundreds of light years away.”

In other questions, Aldrin discussed topics ranging from the privatisation of space travel, to colonising Mars, to curing the moon with Tina Fey