The Ninth Planet

The solar system appears to have a new ninth planet. Two scientists announced evidence that a body nearly the size of Neptune—but as yet unseen—orbits the sun every 15,000 years. During the solar system’s infancy 4.5 billion years ago, they say, the giant planet was knocked out of the planet-forming region near the sun. Slowed down by gas, the planet settled into a distant elliptical orbit, where it still lurks today.


http://www.smh.com.au/technology/sci...20-gmag35.html

Re: The Ninth Planet

They only suspect it's existence by it's effect on the orbits of the other planets.