In addition to the run-of-the-mill spider stars, the researchers also discovered a bizarre black widow-redback crossbreed. The scientists used the now-destroyed Arecibo telescope in Puerto Rico to discover the weirdo stars.

Spider stars are types of millisecond pulsars, or neutron stars that act like precise clocks in the sky, whirling around at least once every 30 milliseconds and flashing like a lighthouse with each rotation. Neutron stars, the tiny, compressed cores of old, exploded stars, often rip material from other stars locked in binary orbits with them and use the push of that infalling material to get up to pulsar speed. Spider stars are rare and special versions of these stars though: They orbit so close to their binary companions that they blast away their surfaces, inhaling vast amounts of material like a spider tearing its partner limb from limb. 

In a new paper, researchers identify three new black widows and a redback in the Milky Way. They also found a spider star that defies categorization, almost like a crossbreed of the two species.