How are the spiral arms of the Milky Way best described functionally?

Answer

Transient, density-wave regions that trigger star formation

The spiral arms are not fixed entities but are areas where density waves compress gas and dust, triggering the formation of new stars as material passes through these regions over galactic timescales.

How are the spiral arms of the Milky Way best described functionally?

#Videos

Which Spiral Arm Of The Galaxy Is Ours? - YouTube

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