Caltech researchers announced today they have found evidence of a giant ninth planet that they’ve nicknamed Planet Nine.
Although they haven’t actually seen it, researchers Konstantin Batygin and Mike Brown said they discovered the planet’s existence through mathematical modeling and computer simulations.
“This would be a real ninth planet,” according to Brown, a planetary astronomy professor. “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.”
According to Caltech, the planet has a mass about 10 times that of Earth and orbits about 20 times farther from the sun on average than Neptune. Researchers said it would take the planet between 10,000 and 20,000 years to make one full orbit around the sun.
Brown noted that there should not be any doubt whether the object is a planet, unlike Pluto, which lost its planetary status and was instead deemed a dwarf planet. The reclassification of Pluto lowered our solar system from nine planets to eight, meaning the newly discovered object would raise our planetary neighborhood back to nine.
Brown said Planet Nine has a mass 5,000 times that of Pluto.
“Although we were initially quite skeptical that this planet could exist, as we continued to investigate its orbit and what it would mean for the outer solar system, we become increasingly convinced that it is out there,” said Batygin, an assistant professor of planetary science. “For the first time in over 150 years, there is solid evidence that the solar system’s planetary census is incomplete.”
