Why aren’t heat shield tiles on rockets and space shhuttles white since white paint reflects heat better?

Question

Why aren’t heat shield tiles on rockets and space shhuttles white since white paint reflects heat better?

In: 5

Answer 1

Because heat shields on rockets/space shuttles are not trying to reflect light. White does not reflect heat better, it reflects light (EM radiation) better. The heat that is dangerous to these crafts when entering/exiting the atmosphere is collision with the gases in our atmosphere at high speeds. So the shield tiles need to be able to withstand the thermal and mechanical impacts, not deal with EM radiation.