A team of scientists has identified the first known candidate binary star system in which both stars have undergone supernova explosions—a discovery that could expand our understanding of how binary star systems form and evolve. IC 443, a supernova remnant also known as the Jellyfish Nebula. Multiwavelength composite image of the IC 443 region. Located in the constellation Gemini, about 6,000 light-years from Earth, IC 443 is one of the most extensively studied supernova remnants, largely because it lies in a particularly complex region. According to the researchers' estimates, the star that produced G189.6+3.3 exploded between 20,000 and 100,000 years before the star that created IC 443.