What is the ultimate fate of the remnant core after the planetary nebula fades away?

Answer

The white dwarf slowly cools over eons to become a black dwarf

After the illuminated gas diffuses into the interstellar medium, the remaining central object, the white dwarf, continues to radiate away its immense residual thermal energy. Over extremely long timescales, it will eventually cool down completely, becoming a cold, dark black dwarf.

What is the ultimate fate of the remnant core after the planetary nebula fades away?

#Videos

How Does A Red Giant Become A Planetary Nebula? - YouTube

How Do Red Giants Create Planetary Nebulae? - Physics Frontier

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