It's a nova - material on a white dwarf exploding. Not a supernova.
To clarify further...
A Nova is not the death throws of a star. The standard nova is a process.
Step 1: Binary system with imbalanced stars.
Step 2: A, the primary, collapses to a white dwarf.
Step 3: B, the companion, is destabilized in orbit, then starts to infall, still burning in the main sequence.
Step 4: As B spirals, it crosses the roche limit, and begins to lose mass to A.
Step 5: when enough "atmosphere" accumulates on A, it fuses.
Step 6: If B survives, it continues to lose mass to A's surface. Go to 5.
Step 6A: eventually, either B impacts A, or B is stripped down to nothing by A, eventually becoming one white dwarf, or maybe even a neutron star.
It can blow up as often as a few decades between bangs, if the stars are close enough.
If big enough, the final BANG from a nova is a type 1A supernova - the mass finally hits the point that the core of A collapses and the shell detonates, usually resulting in a neutron star A and a big ring of ejecta, and a glow that be seen for billions of light years, and can outshine a galaxy... for a few weeks.