It is not planet 9 but another dwarf planet other than Pluto: a research group led byInstitute for Advanced Study (Priceton, USA) found a trace of a celestial body beyond Neptune. Called at the moment 2017 of201seems to have the characteristics to be classified just as a dwarf planet. The new object was officially announced from the Minor Planet Center ofInternational astronomical union last May 21st.
Who is 2017 of201
The team discovered one Extraordinary Transnettunian object (TNO) Margins of our Solar System, potentially large enough to be classified as a dwarf planet, the same category of the well -known Pluto (the transnettunian objects are minor planets that orbit around the sun at a higher average distance than the orbit of Neptune).
The new object is One of the most distant visible objects of our Solar System And it is particular for two reasons: its extreme orbit and its great size. Its discovery suggests, again, that the portion of empty space that is thought to exist beyond Neptune in Kuiper bandIn reality, it is not empty at all. On the other hand, signs of other celestial bodies “from those areas” had already arrived, like thehypothesis of a large planet even like the earth.
The discovery of new planets
The search for distant planets, be they exopiannets (i.e. planets that are outside the sun system) or planets inside our sun system is very complex and is basically based on the search for drops of light when they pass in front of the star around which they orbit.
This technique allowed astronomers of Discover more than 5,500 exoplanets in thirty years (So Nettuno was also discovered) However, he does not provide much information about the nature of these stars and their history.
To determine the chemical composition of the atmospheres of planets far away, astronomers analyze the light of the mother star during the transit of the planetor during his passage in front of the star seen from the earth.
The absorption of part of the star light due to the atmosphere leaves in fact footprints in the star spectrum, that astronomers can reconstruct to determine the gases constituting the same atmosphere of the planet.
How it was discovered 2017 of201
The researchers have used advanced computational methods to identify the characteristic trajectory of the celestial object, with one ‘truly “extreme” orbit.
The aphelium of the object, or the point farthest from the sun on the orbit, is 1600 times further away Compared to that of the terrestrial orbit – explains Sihao Cheng, who guided the work – while his periilio, the closest point to the sun on his orbit, is 44.5 times further than that of the Earth’s orbit, similar to the orbit of Pluto
This orbit, which requires the object about 25,000 years To be completed, it suggests a complex story of gravitational interactions.
He must have undergone close encounters with a giant planet, causing their expulsion on a wide orbit. There may have been more than a phase in its migration, and it is possible that this object was first expelled in the cloud of Oort, the most distant region of our sun system, which houses numerous comets, therefore postponed back
The doors open by this extraordinary discovery
In itself, the discovery of such a “extreme” orbit would not be so particular, but that of 2017 of201 is very particular.
Many extreme transnettunian objects have orbits that seem to be grouped into specific guidelines, but 2017 of201 deviates from this – explains the researcher – this group has been interpreted as indirect proof of the existence of another planet in the Solar Systemthe planet X or the planet nine, which could gradually drive these objects in their observed patterns. The existence of 2017 of201 as an anomalous case of this grouping could potentially question this hypothesis
The diameter of 2017 of201 was estimated by about 700 km, which would make it the second object larger known in such a large orbit (for comparison, the diameter of Pluto is 2,377 km). But further observations are needed, potentially with the use of radio and telescopes, to determine the exact dimensions of the object.
2017 of201 spends only 1% of its orbital time quite close to us to be detectable. The presence of this single object suggests that there could be another hundred other objects with orbit and similar dimensions, which are simply too far away to be detectable at the moment. Even if the progress in telescopes have allowed us to explore remote parts of the universe, there is Still very to discover on our solar system
Because 2017 of201 is not planet 9
Despite some of its characteristics, scientists exclude that it is the famous and equally mysterious planet 9, that scientists are still looking for.
Any planet 9 should in fact have one mass from 5 to 10 times the terrestrial one To explain the gravitational interaction of objects in the distant sun system. But on 2017 of201 astronomers write:
(…) The longitude of the Perdielio of 2017 of201 is found well outside the gravitational interaction observed in extreme transnettunian objectswhich was proposed as a dynamic proof of a distant and not detected planet. This does not mean that there cannot be a planet 9, it only means that this barely discovered body does not have the characteristics that indicate its existence
The search is available on Arxiv.
Sources: Institute for Advanced Study / Arxiv
