Madrid Complutense University researchers may have found Solar System 'Planet Nine'

The campus' pioneering space-matter detection system has found a planet 10 times the size of Earth and at a distance from the latter of 300 to 400 times that of the gap between the Earth and the sun.

Debates among astronomers have been ongoing since early 2016 when California Technology Institute's researchers claimed to have evidence of 'Planet Nine', based upon the unique distribution of orbits found in so-called Trans-Neptunian Objects (TNOs) in the Kuiper belt.

But scientists from the Ossos Project, run by French, Canadian and Hawaiian researchers, found flaws in the hypothesis, saying it could have been an illusion created by random orbit distribution.

Now, though, Complutense astronomers have applied a more exacting and accurate technique allowing them to observe what are known as Extreme Trans-Neptunian Objects (ETNOs) at distances exceeding 150 UA and which never cross Neptune's orbit, and for the first time ever, have studied the distances from the nodes of ETNOs to the sun.

Their results, published in the space magazine MNRAS, suggest there may be a planet in the Solar System even further afield than Pluto.

One of the astrophysics investigators at the Complutense, Carlos de la Fuente Marcos, says the nodes examined are the two points in which the orbit of an ETNO or other astral body crosses the plane of our Solar System, and it is at this point where the probability of interacting with other objects is at its highest.

This means at those points, ETNOs can undergo drastic changes in their orbits, or even suffer collisions.

“If nothing disturbs them, the nodes of these ETNOs should be uniformly distributed, since there's nothing they need to try to avoid, but if there are one or more perturbing factors, one of two situations may arise,” explains De la Fuente Marcos.

“One possibility is that the ETNOs are stable and, in this case, they would ten to have their nodes at a considerable distance from the paths of potential perturbing factors.

“But if they're unstable, they act like those comets that interact with Jupiter, tending to have one of their nodes near the orbit of a potential perturbor.

Spanish scientists have found that the nodes of the 28 ETNOs analysed are grouped together at certain set distances from the sun, and have also found no correlation between the nodes' positions and their inclination – one of the parameters that defines the orientation of the orbits of these frozen space objects.

“Supposing the ETNOs are dynamically similar to the comets that interact with Jupiter, we would interpret these results as signs of the presence of a a planet which was interacting actively with them in a distance range of 300 to 400 UA,” De la Fuente Marcos, explains.

“We do not believe that what we're seeing here is a distortion of the angle of vision.”

De la Fuente Marcos, however, says his team is proceeding with caution since 'given the current definition of a planet', the mystery object found may not be a 'true' planet even if it is 10 times the size of Earth.

“It could be surrounded by enormous asteroids or dwarf planets,” he concludes.

Photograph: NASA