A team of planetary scientists from the California Institute of Technology have published a paper documenting strong circumstantial evidence for a large planet with an orbit outside of Pluto’s. This yet-undiscovered planet is hypothesized to be smaller than Neptune, but would be 10-times more massive than Earth, and comes no closer than 30.5 billion km (19 billion miles) to the Sun.
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"Planet X" may be real: A planet four times the size of Earth may be lurking at the outer edges of our solar system, too far away to be seen by Earth-based telescopes. Astronomers think it’s there because they’ve noticed that something is tugging at small icy objects past Neptune, helping to explain the mystery of those objects’ peculiar orbits.
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There is something out there, and it was first noticed in 1983 when it affected the orbits of Uranus and Neptune. Now, though, there is not single astronomer who will admit its existence. However, its existence was reported in the New York Times almost 30 years ago.
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