Sometimes we can spend five minute just sitting in our car, waiting for the windshield to defog. Thankfully, this former NASA engineer has a science-based method for defogging his windshield faster, and he’s happy to share it. The fog on your windshield is the same as the condensation on your ice cold can of soda in the summer. Warm air can hold more moisture than cold air. Next, turn on your car’s air conditioning.