What stellar remnant causes Planetary Nebulae to glow brightly?

Answer

The hot white dwarf star left at the center.

Planetary nebulae are highly luminous because they glow brightly due to the intense ultraviolet radiation emitted by the hot white dwarf star remaining after the star has ejected its outer gas shells.

What stellar remnant causes Planetary Nebulae to glow brightly?

#Videos

Nebulae: Crash Course Astronomy #36 - YouTube

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