What historical reason led to the misleading name 'planetary nebula'?

Answer

Early astronomers saw them as faint, round, planet-like discs

The name is a historical misnomer because early observers using less powerful telescopes perceived these structures as faint, round objects resembling planets.

What historical reason led to the misleading name 'planetary nebula'?

#Videos

Nebulae: Crash Course Astronomy #36 - YouTube

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