RS Ophiuchi system

A binary system consisting of a white dwarf and a red giant. It is known as a recurrent nova as the red giant is dumping gas onto the surface of the white dwarf, setting off a giant thermonuiclear explosion overy few years. During each outburst, an amount of gas equal to the mass of a standard planet is flung into space.

Some of this ejected matter slams into the extended atmosphere of the inflated red giant, creating blast waves that accelerate electrons to nearly the speed of light. As the electrons travel through the stars' magnetic fields, they emit powerful radio waves. The blast waves move at over 6.4 million kilometers per hour. For a few weeks during each outburst, the white dwarf becomes a red giant as the hydrogen that has been blasted into space fuses into helium.

When the outburst is over, gas will once again build up on the white dwarf and the explosions will begin anew, perhaps in some 20 years time. It's unknown whether the white dwarf casts off all of its accumulated matter during each eruption, or whether some of the material is being hoarded and slowly increasing the mass of the dead star.

If the white dwarf is increasing in mass then it will eventually be ripped apart in a titanic supernova explosion and the cycle of outbursts will come to an end.