What is the primary cause of extreme heating during atmospheric reentry?

Answer

Aerodynamic compression of the air (stagnation heating).

The extreme heating is caused by the violent compression of air molecules in front of the vehicle traveling at hypersonic speeds, a process known as stagnation heating, which transfers heat primarily through convection.

What is the primary cause of extreme heating during atmospheric reentry?
Aerospaceaeronauticsheat shieldthermal protection systemreentry vehicle