The newly discovered planet, named GJ 3512 b, is half the mass of Jupiter. Researchers think its tiny red dwarf host not only likely harbors an additional massive planet, but also ejected another in the past. (Credit: NASA/JPL-Caltech)

Astronomers have discovered a gigantic planet orbiting a puny star some 30 light-years away. And according to current theories, the planet shouldn’t exist. Dubbed GJ 3512 b, the gas giant is at least half the mass of Jupiter. But it orbits a red dwarf star tha