What object remains at the core of a star after it sheds its outer layers to form a planetary nebula?

Answer

A white dwarf.

Planetary nebulae mark the late evolutionary stage of a Sun-like star; after shedding its outer material, the core collapses into a dense remnant known as a white dwarf.

What object remains at the core of a star after it sheds its outer layers to form a planetary nebula?
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