R. Pakmor

Deep in the Galaxy, runaway stars are sometimes born. A monstrous force, a supernova explosion, flings them from their usual place. One such wanderer has recently been found: a star of the LP 40-365 class, a fragment of a white dwarf that survived an incomplete explosion.

Two burned-out stars, each about the size of Earth but heavier than the Sun, spiral ever closer until one crashes into the other. The impact triggers a thermonuclear explosion, giving birth to a type Ia supernova. Such flashes serve as cosmic beacons for measuring distances across the universe. Yet the details of their origin remain hotly debated.