Planet 9 tagged posts

Two new studies by researchers at the University of Colorado Boulder may help to solve one of the biggest mysteries about the dark, icy bodies of the outer solar system: why so many of them don’t circle the sun the way they should.

The outermost reaches of our solar system are a strange place – filled with dark and icy bodies with nicknames like Sedna, Biden and The Goblin, each of which span several hundred miles across.

The orbits of these planetary oddities, which scientists call “detached objects,” tilt and buckle out of the plane of the solar system, amon...

Planet 9 was most likely stolen by our sun 4.5 billion years ago. Credit: Image courtesy of Lund University

Through a computer-simulated study, astronomers at Lund University in Sweden show that it is highly likely that the so-called Planet 9 is an exoplanet. This would make it the first exoplanet to be discovered inside our own solar system. The theory is that our sun, in its youth some 4.5B yrs ago, stole Planet 9 from its original star.

“It is almost ironic that while astronomers often find exoplanets hundreds of light years away in other solar systems, there’s probably one hiding in our own backyard,” says Alexander Mustill, astronomer at Lund University. Stars are born in clusters and often pass by one another...