Prof Brian Cox's superbrain tested to the limit by Joe

Last updated at 06:01
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Watch Joe putting Brian Cox on the spot

Brian Cox goes head to head with fellow superbrain scientist Jeff Forshaw in our science quiz.

Joe tests their physics knowledge to the extreme.

Watch them attempt to explain how things so tiny you can't even see them, like atoms and particles, make up our universe.

Confused? Maybe.

Fascinated? We hope so!