As humans are made up of atoms, is it possible for us to radiate light when we get enough energy? The electrons of our atoms would absorb and radiate energy...

Answer 1

Technically, we radiate in the thermal or infrared light part of the electromagnetic spectrum, which is associated with heat. This is why we can use detectors for infrared light to see animals that radiate heat in the dark (think night vision goggles).

A lot of the time when electrons in molecules absorb energy and reach a higher energy level, the energy isn't dissipated as light, however. This is generally only the case for fluorescent molecules, where light or energy enters the molecule and the energy also leaves as light. Most molecules though will wiggle, or their bonds will act as springs, or gain kinetic energy to dissipate the energy instead of giving off light.