John Williams consulted NASA as he had doubts about the science of 'E.T. the Extra-Terrestrial'.
The 90-year-old composer had doubts about the physics of the famous scene in the Steven Spielberg classic when Elliott and his friends pedal their bicycles over the moon and revealed that he consulted scientists to make sure that it was factually correct.
Speaking at an American Cinematheque event 'Spielberg/Williams: 50 Years of Music and Movies', John said: "The speed of the bicycles that lift up over the moon... that's always bothered me a little bit, especially when I'm conducting it.
"I'm always thinking to myself, what is the escape velocity? How fast do you have to be going to be able to lift it out of gravity? I never know what that was, but it was on my mind."
When the legendary composer received an award from the space agency in 2022, he took the opportunity to get his nagging question answered.
Williams said: "Last year I went to the Kennedy Center to do something musically and NASA decided to give me an award.
"The man presenting it to me was an astronaut, and in a quiet moment I said to him, 'What is escape velocity?' And he said, 'It's 17,500 miles an hour. What happens is you get on a spaceship, and it takes eight minutes to get from zero to 17,500 miles per hour.'"
Williams also revealed that the 1982 sci-fi film is his favourite movie helmed by the legendary filmmaker.
He said: "It's tough to say, because I think 'Saving Private Ryan' is the best Second World War story ever made. But I think 'E.T.' might be Steven's masterpiece. It's almost a perfect film."