What specific condition must be met regarding dust density for a bright blue reflection nebula to be visible?

Answer

The density must be moderate; too dense and blue light is scattered away before reaching us

The dust concentration needs to be balanced. If the cloud is too dense, too much of the preferential blue light is scattered away before it can reach the observer's line of sight, potentially making the nebula dimmer.

What specific condition must be met regarding dust density for a bright blue reflection nebula to be visible?

#Videos

What Makes Reflection Nebulae Appear Blue? - Physics Frontier

Why Are Reflection Nebulae Blue? - Physics Frontier - YouTube

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