Earlier this year, strong evidence for the existence of a massive, undiscovered planet that orbits beyond the reaches of Pluto was presented by the California Institute of Technology, having run detailed computer simulations of the orbits of known trans-Neptunian objects. The simulations showed that the existing orbits of these objects couldn’t follow their current paths without the presence of another planet, approximately ten times the mass of the Earth, with an orbit that comes no closer than 30.5 billion km (19 billion miles) to the Sun.
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