Pluto’s Orbit is Surprisingly Unstable

In 1930, astronomer Clyde Tombaugh discovered the fabled “Ninth Planet” (or “Planet X”) while working at the Lowell Observatory in Flagstaff, Arizona. The existence of this body had been previously predicted based on perturbations in the orbit of Uranus and Neptune. After receiving more than 1,000 suggestions from around the world, and a debate among … Read more