Researchers are closer than ever to proving the existence of the elusive Planet Nine.
Two new studies have shed further light on the theory that there’s an enormous planet at the edge of the Solar System; an idea first proposed earlier this year. While the planet has yet to be directly observed, astronomers believe it’s roughly 70 times more distant from the Sun than our planet.
Now, researchers from the California Institute of Technology - including the proposers of Planet Nine, Mike Brown and Konstantin Batygin - believe the six-degree tilt observed in the Sun compared to the plane of the Solar System may actually be a result of Planet Nine’s pull.
"Because Planet Nine is so massive and has an orbit tilted compared to the other planets, the Solar System has no choice but to slowly twist out of alignment," lead author Elizabeth Bailey said in a statement.
One paper in the Astrophysical Journal looks at the angular momentum contribution of Planet Nine on the spin of our star. Researchers think the potential planet is thought to arrive as close as 200 AU (astronomical unit) and as far away as 1,200 AU, with 1 AU being the Earth-Sun distance. Having an object that’s at least 10 times the mass of Earth on such an expansive orbit, and with an anticipated inclination of 30 degrees, will cause a wobble in the Sun. According to researchers’ calculations, this could explain the evident tilt.
Another study in the Astrophysical Journal Letters looks at a different piece of evidence. These researchers deduce that the orbit of four minor objects in the Kuiper belt, including the planet Sedna, aren’t random; the cause of which seems to be an enormous object with characteristics similar to those expected of Planet Nine.
"We analyzed the data of these most distant Kuiper Belt objects, and noticed something peculiar, suggesting they were in some kind of resonances with an unseen planet," said lead author Renu Malhotra of University of Arizona in a statement.
"Our paper provides more specific estimates for the mass and orbit that this planet would have, and, more importantly, constraints on its current position within its orbit."
While neither of these studies offers conclusive evidence of Planet Nine, researchers believe a direct observation could be three or more years away.