A team of researchers from the Harvard-Smithsonian Center for Astrophysics has released a paper outlining the probability for each of the three leading theories explaining how the phantom "Planet Nine" could have ended up in its current theorized orbit.
The existence of Planet Nine is predicated on a series of computer simulations ran by a pair of Caltech scientists to explain the trajectory of six Kuiper Belt objects, which may have been sent in to highly eccentric orbits after an encounter with a huge body roughly 10 times the mass of Earth.
The researchers asserted that the planet takes between 10 - 20 thousand years to traverse a single, highly-elliptical orbit, ranging between 40 and 140 billion miles from the Sun.
The new research from the Harvard-Smithsonian Center for Astrophysics made use of millions of computer simulations to calculate the likelihood for the three most plausible explanations for the scenic route taken by the phantom planet.
The first, and by far the most probable theory involves a wandering star that most likely formed alongside our Sun barreling past our solar system, and catching the planet in its powerful gravitational pull. This explanation would account for the highly elliptical trajectory of Planet Nine, but only if the body were already in a relatively far-flung orbit at the time of the pass.
This could have been the case if Planet Nine took the form of a gas giant, which, after forming close to our star, was then incrementally nudged into a more distant orbit by the influence of Jupiter and Saturn. It is also possible that the planet could have formed in a distant orbit in the disk of gas left over from the creation of our solar system, in which case it would likely bear a striking resemblance to Pluto.
Even though this is the most likely explanation offered to date the computer simulations run by the researchers only place the probability of a star being on the cause of Planet Nine's elongated orbit at around 10 percent.
The final two theories considered by the researchers suggested that Planet Nine was either a body captured from another passing solar system, or a rogue planet snared by the gravitational pull of our star. Computer modelling placed the likelihood of either origin story below the two percent threshold, leaving the orbit of our mysterious neighbour a matter of hot debate.
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