Professor Hawking has admitted he was a slacker at university.
As a student of natural science at Oxford University, he once calculated that he did about 1,000 hours of work during his three years at Oxford - an average of an hour a day.
"I'm not proud of this, I'm just describing my attitude at the time, shared by most of my fellow students," Prof Hawking told an event to celebrate the launch of the Science Museum's new "Collider" exhibition.
"Because of my lack of work, I had planned to get through the final exam by doing problems in theoretical physics and avoiding questions that required factual knowledge.
"But I didn't sleep the night before the exam, because of nervous tension, and so I didn't do very well. I was on the borderline between a first and second class degree."
Nonetheless, Hawking was awarded a first and went on to pursue a glittering career in mathematics and cosmology at Cambridge University, where he is now Director of Research at the Department of Applied Mathematics and Theoretical Physics.