The hunt for ‘Planet Nine’: Why there could still be something massive at the edge of the solar system
Is there a massive unknown planet on the external scope of the solar system? The idea has existed since before the discovery of Pluto In the 1930s. Latopped as planet X, eminent astronomers had put it forward as an explanation of the orbit of Uranus, which derives from the way of the orbital movement that physics would expect it to follow. The gravitational attraction of a non -discovery planet, several times greater than Earthwas considered a possible reason for the gap.
This mystery was finally explained by a recalculation of the mass of Neptune in the 1990s, but then a new theory On a potential planet, Nine was offered in 2016 by astronomers Konstantin Batygin and Mike Brown in Caltech (California Institute of Technology).
Their theory concerns the Kuiper belt, a giant belt of dwarf planets, asteroids and other materials which is beyond Neptune (and includes Pluto). Many kuiper belt objects – also called trans -neptunian objects – were discovered in orbit around the sun, but like Uranus, they do not do it in a Direction expected continues. Batygin and Brown argued that something with a large gravitational traction must affect their orbit and that Planet Nine proposed as a potential explanation.
It would be comparable to what is happening with ours Moon. It orbit the sun every 365.25 days, in accordance with what you expect because of their distance. However, the gravitational attraction of the earth is such that the moon also orbits the planet every 27 days. From the point of view of an outside observer, the moon moves in a spiral. Likewise, many objects from the Kuiper belt show that the signs of their orbits are affected by more than the gravity of the sun.
While astronomers and space scientists were initially skeptical about the theory of the new planet, there was Assembly evidence Thanks to increasingly powerful observations according to which the orbits of trans-nine objects are indeed erratic. Brown said in 2024::
“I think it is very unlikely that P9 does not exist. There is currently no other explanation of the effects we see, nor for the myriad of other effects induced by P9 that we see on the solar system.”
In relation: Astronomers discover a new “ammonite” dwarf planet – and this could upset the existence of the planet new
In 2018, for example, it was announced that there was a new candidate for a dwarf planet in orbit around the sun, called 2017 of 201. This object measures approximately 700 km in diameter (the earth is approximately 18 times larger) and has a highly elliptical orbit. This lack of orbit almost circular Around the sun suggested either an impact at the beginning of his life which put it on this path, or a gravitational influence of Planet Nine.
Problems with theory
On the other hand, if Planet nine exists, why has no one found it yet? Some astronomers wonder if there is Enough orbital data Kuiper objects to justify any conclusion on its existence, while alternative explanations are presented for their request, as the effect of a debris ring or the most fantastic idea of a black hole.
The biggest problem, however, is that the external solar system has simply not been observed for quite a long time. For example, the 2017 object of 2017 has an orbital period of around 24,000 years. Although the orbital path of an object around the sun can be found in a short number of years, all gravitational effects probably need four to five orbits to notice subtle changes.
New discoveries of objects in the Kuiper belt have also presented challenges for the theory of the new planet. The last is known as 2023 kq14an object discovered by the Subaru telescope in Hawaii.
It is known as a “sednoid”, which means that it spends most of its time away from the sun, although in the vast area in which the sun has a gravitational traction (this area is around 5,000 with astronomical units, where the distance of the earth in the sun). The classification of the object as a senoid also means that the gravitational influence of Neptune has little or no effect on this subject.
The closest approach to 2023 kq14 of the sun is around 71au, while its furthest point is around 433au. In comparison, Neptune is about 30 in the sun. This new object is another with a very elliptical orbit, but it is stable that 2017 of 2017, which suggests that no large planet, including a new hypothetical planet, considerably affects its path. If Planet nine exists, it would therefore be necessary to be further from 500 in the sun.
To worsen things for the theory of the new planet, it is the fourth sednoid to discover. THE three others Also exposure stable orbitsuggesting as well as any new planet should be far away.
Nevertheless, the possibility remains that there could still be a massive planet affecting bodies orbits in the Kuiper belt. But the ability of astronomers to find such a planet remains somewhat limited by the restrictions of space trips even without pilot. It would take a spacecraft 118 years to travel far enough to find it, on the basis of the estimates of the speed of The new horizons of NASA explorer.
This means that we will have to continue to count on ground telescopes and in space to detect anything. New asteroids and distant objects are discovered all the time as our observation capacities become more detailed, which should gradually light up more what could be there. So look at this (very large) space, and see what emerges in the years to come.
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