The mythical “Planet X” may actually be real, and scientists are calling it “Planet Nine.”
Astronomers have found evidence for a planet 10 times more massive than Earth in the far outer solar system, orbiting about 20 times farther from the sun than distant Neptune does.
“This would be a real ninth planet,” one of the researchers, Mike Brown of the California Institute of Technology (Caltech) in Pasadena, said in a statement. “There have only been two true planets discovered since ancient times, and this would be a third. It’s a pretty substantial chunk of our solar system that’s still out there to be found, which is pretty exciting.”
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