Astronomers Michael Brown and Konstantin Batygin announced on Wednesday evidence of a hitherto unknown giant planet hidden in the dark depths of the solar system.
The scientists, who work at the California Institute of Technology, called the discovery “Planet Nine,” which is located far beyond Pluto and is five to 10 times bigger than Earth.
The planet has not been seen it directly, but its existence has been extrapolated from the movement of dwarf planets in the outer solar system.
According to a paper published in the Astronomical Journal, a “massive perturber” is affecting the gravity of small objects, suggesting the existence of a large object.
Scientists around the world have trained their telescopes on the sky searching for the new planet. However, even with a diameter four times that of Earth, it sits at least 20 times further away than Neptune, testing even the strongest instruments.
Until a decade ago, Pluto was considered the ninth planet, however due to the work of Brown and others it was demoted to the status of a dwarf planet.
Astronomers Scott Sheppard and Chad Trujillo mooted a ninth planet in 2014 after observing the movement of planetoids. Brown and Batygin set out to prove them wrong but ended up confirming their thesis using computer models.
The ninth planet is "much more of a possibility with this new work," said Sheppard on Wednesday. "There is no planet found. It's all circumstantial evidence. It's like we're at a crime scene looking at the blood on the wall, and we're trying to explain how the person died."
In a statement, Brown said, “Planet Nine would take 20,000 years to orbit the sun."
"This would be a real ninth planet," he added. "There have only been two true planets discovered since ancient times, and this would be a third. It's a pretty substantial chunk of our solar system that's still out there to be found, which is pretty exciting."