假超新星有时也称为第五型超新星，是类似海山二的，和高光度蓝变星（LBV）的巨大喷发现象。

它们起初看起来像是超新星爆炸，但是并没有造成恒星本身的毁坏。同样的，它们应该被视为特别强而有力的新星。

Supernova impostors are stellar explosions that appear at first to be a type of supernova but do not destroy their progenitor stars. As such, they are a class of extra-powerful novae. They are also known as Type V supernovae, Eta Carinae analogs, and giant eruptions of luminous blue variables LBV.