Is Planet X real? Looks like it.

From Science:

The solar system appears to have a new ninth planet. Today, 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.

Batygin and Brown inferred its presence from the peculiar clustering of six previously known objects that orbit beyond Neptune. They say there’s only a 0.007% chance, or about one in 15,000, that the clustering could be a coincidence. Instead, they say, a planet with the mass of 10 Earths has shepherded the six objects into their strange elliptical orbits, tilted out of the plane of the solar system.

From Gizmodo:

The researchers studied six small objects in the Kuiper belt and noticed their orbits funneled toward the sun in a very specific formation. The likelihood of this being a coincidence is slim to none. What researchers believe is that a new planet, unofficially dubbed “Planet X,” is pulling these objects into its orbit.