Which specific atomic transition in hydrogen is responsible for the nebula's dominant red glow?

Answer

Hydrogen-alpha ($ ext{H} extalpha$)

The $ ext{H} extalpha$ transition occurs when a hydrogen atom’s electron drops from the third energy level ($n=3$) down to the second energy level ($n=2$).

Which specific atomic transition in hydrogen is responsible for the nebula's dominant red glow?

#Videos

How Does Ionization Cause Emission Nebulae To Glow? - YouTube

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