Answer: supernovae

AnswerCrossword Clue
SUPERNOVAEStarbursts
SUPERNOVAEExploding stars
supernovaeA star that suddenly increases greatly in brightness because of a catastrophic explosion that ejects most of its mass
supernovaeSUPERNOVA, (Latin) a very brilliant nova resulting from an explosion which blows the star's material into space, leaving an expanding cloud of gas