There could be a planet hiding on the television in our solar system. And astronomers have released new details about what it probably looks like if it really exists.
Planet 9, according to a new paper released online on February 10 in the journal Physics Reports, is probably five to ten times the Earth's mass. And it probably travels along an elongated path that spins 400 times the Earth's distance from the sun. This circuit is also probably 15 to 25 degrees away from our solar system, where most planets strike.
The existence of Planet Nine, which Live Science's sister site Space.com previously reported, is an idea that has become popular among astronomers ever since it was first seriously proposed back in 2014. Researchers suspect the planet's existence due to patterns of objects in the Kuiper Belt, a ring of dirt in the outer solar system. These objects tend to clump together in ways that suggest that gravity from something large out there shifts them.
And the evidence has only become stronger. In a separate paper, published on January 22 in the Astronomical Journal, some of the same authors of the Physics Report constituted the probability that Planet Nine did not exist in only 1 in 500. [Amazing Astronomy: Victorian-Era Illustrations of the Heavens]
Strongly suspected that the dark planet exists is not the same as knowing it is right, though. The good news is that this new research suggests that Planet Nine is much closer than previously thought. But astronomers still have plenty of room to search for it.
However, the authors of the Physics Reports paper increased the possibility that there was no planet out there at all. They added, however, that strong current evidence is that the chance must be "taken seriously".
The most likely alternative explanation is that humanity's image of the Kuiper Belt is incomplete and that the objects only seem to cluster due to some interference in the effort to detect them. It is also possible that the authors suggested that the cluster be due to "even the gravitational force" of the Kuiper belt which acts on its own objects and does not derive from nothing hidden the planet's tug of war.
Still, astronomers have become more convinced of evidence of Planet Nine in recent years. And now they are making significant progress towards identifying it in space.
Originally published on Live Science .