If a bright star appears distinctly orange or red, what is the most likely reason for its high apparent brightness?

Answer

It is intrinsically enormous—a giant or supergiant that has swelled up.

Red or orange bright stars like Betelgeuse and Arcturus are typically older, highly expanded giants or supergiants whose immense physical bulk compensates for distance or a cooler temperature.

If a bright star appears distinctly orange or red, what is the most likely reason for its high apparent brightness?

#Videos

STAR BRIGHTNESS EXPLAINED - YouTube

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