This Weird Star Survived a Supernova Only to Shine Even More Brightly Than Before - ScienceAlert

Images of its home galaxy went back for years prior, so working out which star went bang simply required studying follow-up images to spot the now empty spaces.

Either the star would have completely gone away, or maybe it would have still been there, meaning the star we saw in the pre-explosion images wasn't the one that blew up," says UC Santa Barbara astronomer Curtis McCully.

Usually, there's nothing of note left in the space once occupied by the white dwarf – just an expanding cloud of star guts drifting out into the cosmos, faintly glowing with residual radiation.

The left panel shows the Hubble Heritage (pre-explosion) image of NGC 1309.

The top-middle panel shows a zoom-in on the position of the supernova from the pre-explosion image.

The bottom-right panel shows the difference image between the pre-explosion images and the observations from 2016.

Finding SN 2012Z radiating furiously after its own supernova leaves little doubt that in some, if not many cases, white dwarfs can remain intact even after going thermonuclear.