How luminous can a supernova explosion become compared to other celestial objects?

Answer

It can briefly outshine entire galaxies, shining as brightly as a billion suns.

The sheer energy release causes supernovae to exhibit staggering luminosity, capable of briefly surpassing the light output of every star combined in the galaxy where the explosion occurs, reaching the brightness equivalent to a billion suns.

How luminous can a supernova explosion become compared to other celestial objects?
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