Stephen Hawking persuaded Buzz Aldrin that humans should return to the Moon before venturing to Mars.

The Apollo 11 astronaut said that the late astrophysicist was convinced that space agencies should be concentrating on getting back to the lunar surface, from where they could plan a new mission further into the Solar System.

Speaking at the Starmus festival in Zurich, where he was presented with the Stephen Hawking Medal for Lifetime Achievement, Aldrin, 89, said: “There was a time when I was in his office in Cambridge and at that time I had been anxious that we should make a continuous orbit between Earth and Mars, and he started tapping out letters with his cheek, the way he did.

“And it was rather time consuming, and I waited for this really long time. And eventually he said, in that computerised voice of his, ‘colonise the Moon first’ and since that time I realised there are so many things we need to do before we send people to Mars and the Moon is absolutely the best place to do that.

“And hopefully we can do it with international partners so they can help to pay the bills.”