Astronomers Konstantin Batygin and Michael Brown of the California Institute of Technology in Pasadena have released new details about a hypothetical ninth planet in the solar system that are changing the idea of where it is.
According to scientists, who first suggested its existence in 2016, the mysterious planet X is flying in a more eccentric, that is, more elongated orbit. The calculation results available in the arXiv repository and accepted for publication in The Astrophysical Journal Letters will help you find the planet, if it really exists.
The main evidence was the apparent clustering of the orbits of six extreme trans-Neptunian objects (ETNOs), which never approach the Sun closer than 30 astronomical units (AU) and can move away from it by more than 150 AU. (the average distance from the Earth to the Sun is conventionally taken as a.u.).
The orbits of ETNO are located so that their apse lines, connecting the point of the orbit closest to the Sun with the most distant point, are approximately at the same angle. This alignment is explained by the existence of a large body, the gravity of which affects ETNO.
Since more ETNOs have been discovered since then, astronomers revised the data in 2019. The mass of the planet should be only five times the mass of the Earth (and not ten times), and its orbit was characterized by a small eccentricity.
However, now Batygin and Brown have renewed their hypothesis again, this time taking into account what influence the planet should have had on the icy bodies of the Oort Cloud over the entire existence of the solar system.
“The ninth planet, however, qualitatively changes this picture,” – the researchers said.
“Due to the prolonged gravitational pull of the orbit of the Ninth Planet, the internal objects of the Oort Cloud evolve on billionth time scales, slowly returning to the outer solar system. So what happens to them? We modeled this process by considering disturbances from canon giant planets, Planet Nine, passing stars, and galactic tide. It turned out that reintroduced Oort Cloud objects can easily mix with many bodies in the Kuiper belt and even exhibit orbital clustering,” they write.
This means that some of the extreme trans-Neptunian objects we discovered may have actually originated in the Oort Cloud, which is really cool and unusual. However, the team’s modeling also showed that the clustering of Oort Cloud objects will be weaker than the clustering of objects coming from the Kuiper belt closer to it.
The sun probably formed in a star-forming cloud along with other stars. Under these conditions, an internal Oort cloud should have appeared around the young solar system, since passing stars would push ice bodies towards the Sun.
New simulations have shown that Planet Nine over billions of years of existence should influence the orbits of bodies in the cloud, which would mix with the ETNO of the Kuiper belt and demonstrate orbital clustering, which, however, is weaker than that of trans-Neptunian bodies.
Taken together, the results indicate that planet X is required with a more distant and elongated orbit than previous studies suggested, scientists say. At the same time, the eccentricity cannot be too great, because it would change the observed clustering pattern.
This suggests that Planet Nine’s more eccentric orbit explains the data better than the orbit suggested by the researchers in a 2019 article. However, we will not find out the exact numbers and coordinates of the alleged planet until additional research is carried out on this topic – we will wait for news.