Every couple of decades, the star system V2487 Ophiuchi produces a massive explosion. Gas that’s piled up on one of its stars is blasted into space, making the system shine thousands of times brighter than average. The last such outburst was seen 24 years ago today, in fact.
But you don’t have to wait that long to see fireworks from the system. About once a day, it produces a “superflare” — a deadly outburst of radiation that dwarfs anything seen from the Sun.
The system consists of two stars. One is similar to the Sun, while the other is a white dwarf — the dead core of a once normal star. They’re so close together that the white dwarf “steals” gas from the other star. The gas forms a disk around the white dwarf.
Because the stars are so close, the companion spins rapidly. That generates a powerful magnetic field. And according to a study by astronomers at LSU, that’s the source of the superflares. Magnetic field lines extend into the disk around the white dwarf — or even to the white dwarf itself. The lines quickly become twisted and tangled. Then they snap, releasing huge amounts of energy — a superflare.
The largest one yet seen was 20 million times more powerful than the largest flare ever seen on the Sun. And a typical flare is about 10 times larger than those seen from any other star. The flares would strip away the atmospheres of orbiting planets, and destroy any life — making V2487 Ophiuchi a place to avoid.