A New Study Reveals Planet Nine Isn’t Needed To Create The Bizarre Orbits Of Objects In Outer Solar System

New research suggests that trans-Neptunian Objects (TNOs) may be creating the odd orbits of objects in the outer system rather than Planet Nine.

the hypothetical planet nine in front of stars lit by the Sun.
Dotted Yeti / Shutterstock

New research suggests that trans-Neptunian Objects (TNOs) may be creating the odd orbits of objects in the outer system rather than Planet Nine.

A new study suggests that there is no need for Planet Nine as the seemingly bizarre orbits of objects that are found in the furthest reaches of the solar system can still be explained even without the existence of this elusive planet.

As Space reported, the strange gravitational pull that has been detected exerting an influence on these objects may actually come about through trans-Neptunian objects (TNOs) instead of the as yet undiscovered Planet Nine, according to lead author Antranik Sefilian from Cambridge University.

“If you remove Planet Nine from the model, and instead allow for lots of small objects scattered across a wide area, collective attractions between those objects could just as easily account for the eccentric orbits we see in some TNOs.”

Scientists first began seriously searching for Planet Nine, which has also been called both Planet X and Giant Planet Five, only fairly recently, in 2014. It was astronomers Scott Sheppard and Chad Trujillo who originally suggested that there may be a “perturber” planet located beyond the reach of Neptune that exerted such a powerful influence that its gravity affected the strange rotation of far-flung planets like 2012 VP113 and Sedna.

However, two years later in 2016, Konstantin Batygin and Mike Brown also suggested that TNOs may be just as responsible for the orbits of these dwarf planets, and as time has marched on, astronomers have now found so many “clustered” TNOs that these are presently believed to total around 30 in number.

So while it is still theoretically possible that there may be a Planet Nine lurking out there somewhere, Sefilian and Jihad Touma’s new study suggests that it isn’t really needed to create the orbits that have been seen in some bodies in the outer system, according to ScienceAlert.

As Sefilian explained, “The Planet Nine hypothesis is a fascinating one, but if the hypothesized ninth planet exists, it has so far avoided detection. We thought, rather than allowing for a ninth planet, and then worry about its formation and unusual orbit, why not simply account for the gravity of small objects constituting a disk beyond the orbit of Neptune and see what it does for us?”

To do this, Sefilian and Touma built a computer model of TNOs that had become detached, taking care to also include the planets in the solar system, along with debris that is scattered well beyond the orbit of Neptune. After analyzing this model, Sefilian noted that even if Planet Nine was completely removed, the odd orbits of objects would still be seen.

“If you remove Planet Nine from the model, and instead allow for lots of small objects scattered across a wide area, collective attractions between those objects could just as easily account for the eccentric orbits we see in some TNOs.”

The new study which, while not discounting the existence of Planet Nine, suggests that this planet isn’t needed to produce the strange orbits seen in objects in the outer solar system is available in pre-print on arXiv.