Question

Why is light from the moon called cool light while light from the sun called hot light?

Answer 1

Sunlight comes straight from the sun and onto the earth has an extreme amount of energy. So it is called hot light.

Moon light comes from the sun, but instead of hitting earth right away, it hits the moon and then reflects off of it onto the earth. It is also hot, but not much as that of light from the sun.
The moon doesn't reflect all the photons of light which it gets, the process of reflection absorbs the fraction of energy by the surface of the moon. So the light provided by the moon has less energy, so it is not that much hot as the light of the sun. So it is called cool light.