How does the duration of successive core burning stages in a massive Red Supergiant generally compare to the star's main sequence life?

Answer

They are progressively shorter, sometimes lasting mere hours.

While a star spends billions of years on the main sequence, the successive core burning stages in a massive Red Supergiant are incredibly brief, with final stages sometimes lasting mere days or hours.

How does the duration of successive core burning stages in a massive Red Supergiant generally compare to the star's main sequence life?

#Videos

How Do Red Giants Become Supernovae? - Physics Frontier

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