If placed where the Sun resides, how far might the outer atmosphere of a red supergiant extend?

Answer

Past the orbit of Jupiter, possibly even reaching Saturn

The scale of these stars is immense; if one occupied the Sun's position, its outer atmosphere would extend beyond Jupiter's orbit, potentially reaching Saturn.

If placed where the Sun resides, how far might the outer atmosphere of a red supergiant extend?

#Videos

How Does A Red Supergiant Become A Supernova? - Physics Frontier

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