The Heating Up of a Spacecraft

The heating up of a spacecraft as it reenters and descends through the atmosphere is not mostly caused by friction, which is only responsible for a small amount of the heat. It's moving so fast that the air does not have time to get out of the way. And even if it were entering in a more aerodynamic way, Heat would probably still happen because it's moving sofast that it compresses air. The air gets so hot that it radiates heat then causes the spacecraft to be somebody.