What generates the light emitted by a white dwarf after it has exhausted its fusion fuel?

Answer

Residual kinetic energy, or stored heat

White dwarfs are cooling stellar cinders that are no longer generating new energy via fusion; their light output is simply the stored heat from their active lifetimes, which slowly dissipates.

What generates the light emitted by a white dwarf after it has exhausted its fusion fuel?

#Videos

How Do Stars Produce Light? - Physics Frontier - YouTube

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