Astronomers have discovered that a huge planet and star 104 light years from Earth form the largest solar system ever seen. The planet, dubbed 2MASS J2126-8140, and its red dwarf star are a full 7,000 astronomical units (AUs) apart, or a trillion miles (an AU is the distance between the Earth and the sun). Researchers previously thought the planet was "rogue," roaming the galaxy alone. In fact, they're so distant that if the star exploded, citizens of planet 2MASS wouldn't know about it for a full 62 days. Given its bizarre characteristics, however, it's unlikely that anyone lives there.