Professor Brian Cox has told how he wrote off his first car after "wrapping it around a lamppost".
The scientist will appear in Sunday's episode of Top Gear as a celebrity guest alongside adventurer Bear Grylls.
Professor Cox told the show's host Chris Evans about being accident prone when it comes to cars.
"I ended up wrapping it around a lamppost," he explained of his first accident.
Chris enquired if he had been "racing a Mini at the time", to which he replied: "No, no, no, because that would be a naughty thing to do."
Explaining what Top Gear host Evans described as the "greatest excuse of all time" for a car accident, the professor said: "Motion is relative. And so it is perfectly possible to define myself as being in what's called an inertia frame of reference.
"As long as I wasn't accelerating in the car, and so the lamppost was moving towards me! And that's what happened, you're right that relativity could have stepped in."
The particle physicist also details his "haphazard history" with cars, including a Escort that blew up on the motorway and a Rover 213 SE which he drove into the side of a transit van.
The episode also sees Chris, with co-hosts Matt LeBlanc and Sabine Schmitz, buying cheap second-hand cars and heading to Venice, Italy.