Astronomers Think Planet 9 is From Another Star

Posted on June 1, 2016

Astronomers say Planet 9 is from another star. They say it was originally part of some other solar system before being captured by our sun. Evidence for this ninth planet was revealed earlier this year.

The astronomers from Lund University in Sweden say their theory is that our sun stole the planet 4.5 billion years ago from its original sun. Stars do pass each other in space and a star can "steal" planets in orbit around another star during this passing.

Alexander Mustill, a Lund astronomer, says in a statement, "Planet 9 may very well have been 'shoved' by other planets, and when it ended up in an orbit that was too wide around its own star, our sun may have taken the opportunity to steal and capture Planet 9 from its original star. When the sun later departed from the stellar cluster in which it was born, Planet 9 was stuck in an orbit around the sun. "

We still don't know what Planet 9 is made of. It is suspected to have about ten times the mass of the Earth. Mustill says, "This is the only exoplanet that we, realistically, would be able to reach using a space probe."

Mustill explains the Planet 9 theory in the following video:

The research paper was published here in the journal, Monthly Notices of the Royal Astronomical Society Letters.



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