Astronomers have shown that dead stars known as white dwarfs can re-ignite and explode as supernovas.

The discovery appears to solve a mystery surrounding the nature of a particular category of stellar explosions known as Type Ia supernovas.

Theorists suspected that white dwarfs could explode due to a disruptive interaction with a companion star, but lacked definitive evidence until now.

Details of the research appear in the journal Nature.

The “smoking gun” in this case was the detection of radioactive nuclei being generated by nuclear fusion in the cosmic blast.

More: Dead Stars ‘Can Re-Ignite’ and Explode