February 24, 2024

Planet 9 may have left the solar system billions of years ago

  1. Homepage
  2. Let's know

Research suspects the presence of an undiscovered planet in the solar system influencing Sedna's orbits. However, the search could now end in vain.

British Columbia – Astronomers searching for a planet that can't be found? The asteroid Sedna, located behind the Kuiper Belt, has puzzled astronomers since its discovery. Most distant objects in our solar system are affected by Neptune. The asteroid, which is likely a dwarf planet, does not come close to the planet. Therefore, it was assumed that a collision with a larger, unknown object must have put “Planet 9” Sedna into its orbit. Researchers have been looking for this – to no avail.

Researchers search for 'Planet 9', which is said to have an influence on Sedna © UPI Photo/Imago

Doubts about the unknown “Planet 9” theory

Yukun Huang from the University of British Columbia in Canada doubts that the supposed “Planet Nine” can be found. high Results of his research This planet does not exist in our solar system, or at least it no longer exists. While it is clear that large objects determined the orbits of Sedna and two recently discovered Sednoids, they could have left the solar system 4.5 billion years ago.

The researcher tests his theory. If there is no undiscovered “Planet 9”, the orbits of the Sednoids should be stable for billions of years. They are close enough to the Sun not to be affected by galactic tides and at the same time far enough from the larger planets not to affect their orbits.

The computer simulation aims to provide clarity about the origin

Using computer simulations, Huang recreated the universe as it looked billions of years ago. Shortly after the birth of the solar system, the three Sednoids show strong similarities. Their perihelion, the point in their orbit closest to the sun, was all on the same longitude. Their apse lines, the line connecting perihelion, sun, and apogee, were also nearly identical.

Trans-Neptunian object, Sedna solar system, Kuiper solar system
The location of the trans-Neptunian body in our solar system © UPI Photo/Imago

Not “Planet 9”, but a single event responsible for Sedna's orbit?

All these similarities indicate that an event placed the celestial bodies in their orbits 4 billion years ago. He also notes that there has been no disturbance to their orbit since then. According to Huang's research, it is unlikely to find an undiscovered planet in our solar system responsible for the orbit of a cyanoid.

Huang suggests that it was a primitive planet and no longer orbited the center of the galaxy instead of the Sun. But there is also the possibility that a star from the Sun's birth cluster influenced the orbit. As more Sednoids are discovered, their orbits will also be tracked back in time to test the single-event hypothesis. Recently, attempts have also been made to explain motions in the Kuiper Belt using the theory of gravity.