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Planet 9 from outer space

Astronomers have long sought a planet in our solar system beyond Pluto, and now a team thinks they've identified its fingerprints.

Astronomers think they've discovered signs of a planet way beyond Pluto

Artist's impression of "Planet Nine" looking back towards the distant Sun (lower right). (Caltech/R. Hurt (IPAC))
For more than a century, astronomers have suggested that there might be another planet hiding out in the distant reaches of the solar system - somewhere beyond Pluto. And the fruitless search for such a planet has destroyed careers and reputations.

Now, Dr. Mike Brown, a professor of Planetary Astronomy at the California Institute of Technology, is putting his reputation on the line by suggesting that he can see evidence of a nearly Neptune-sized planet perturbing the orbits of dwarf planets in the Kuiper Belt.

This hypothetical ninth planet would have a highly elliptical orbit, and circle the sun every 10 to 20 thousand years. Dr. Brown and his colleagues are now searching the skies for the faint and distant body using powerful telescopes.

Related Links

Paper in The Astronomical Journal
- Caltech release
Nature news story
- Science news story
New Yorker story