What process makes an emission nebula glow?

Question

Quizplus · Accepted Answer

Emission nebulae glow due to the process of light emitted when electrons jump between energy states in hydrogen atoms. This is especially true for the most common type of emission nebula, the H II region, which is made up of ionized hydrogen gas. When electrons are excited by high-energy radiation from nearby stars or other sources, they jump to higher energy states, and then fall back down to lower energy states, releasing energy in the form of light. This light is what gives the nebula its characteristic glow.

What Process Makes an Emission Nebula Glow