c8601605cec84da8fef510ddfbfe5d4ac9c985f4It was an elusive planet that for 200 years appeared to explain Uranus’s wobbly orbit. And there was the sister sun theorized to be near our solar system that caused asteroids to swerve toward Earth. There is just one problem: neither “Planet X” nor “Nemesis” ever existed, researchers now say. Or probably not. “The outer solar system probably does not contain a large gas giant planet (“Planet X”), or a small, companion star (“Nemesis”),” concluded University of Pennsylvania astronomer Kevin Luhman, who directed the study using NASA’s Wide-field Infrared Survey Explorer (WISE) telescope. The results were published in the most recent edition of The Astrophysical Journal. MORE