Two bodies at different temperatures in vacuum constantly exchange heat. Researchers have devised a formula that describes the maximum heat transfer in such scenarios. Surprisingly the formula suggests that a million times more heat transfer is possible between close objects than previously thought.

See the source article by following the link below:
Two bodies at different temperatures in vacuum constantly exchange heat. Researchers have devised a formula that describes the maximum heat transfer in such scenarios. Surprisingly the formula suggests that a million times more heat transfer is possible between close objects than previously thought.