Under what conditions can a supernova sometimes surpass the luminosity of its host galaxy?

Answer

Its sheer wattage can exceed the combined light of the thousands of stars making up the host galaxy.

The energy released during the explosion can be so staggering that the transient astronomical object temporarily shines brighter than the combined light output of the entire galaxy hosting it.

Under what conditions can a supernova sometimes surpass the luminosity of its host galaxy?
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