Here’s something that might help you this winter. A former engineer for NASA recently did a bunch of tests, and figured out how to defrost the windows in your car twice as fast. Here are the four things you need to do:

1. Turn your heater up all the way. Hot air can hold more moisture than cold air, and that’s why blasting your windshield with hot air works better.

2. Turn your A/C on. Air conditioners pull moisture out of the air, which is key.

3. Make sure your air circulation setting is OFF. It’s usually a button with a picture of a car, and there’s a circular arrow in the middle of it. When it’s on, it only recirculates air that’s already inside your car.

The reason you want it off is because the air outside your car is colder. And cold air can’t hold as much moisture. So you want to draw it in and heat it up, so it sucks up more of the moisture that’s ALREADY in your car.

4. Crack your windows for a few seconds. Again, it’s about getting the humid air out, and the dry air in.

He also found you can prevent your windows from fogging up in the first place by wiping down the inside with shaving cream.