Despite centuries of research, astronomers have so far discovered only two new planets in our solar system – 1781 Uranus and Neptune of 1846, while Pluto was downgraded to "dwarf planet" many years after its discovery in 1930. But the search for a possible ninth planet continues intensely. In a technical paper, Konstantin Batygin of the California Institute of Technology and colleagues have now put together what was discovered in the last two decades and have reached an interesting prognosis: "If planet 9 exists, it will probably be discovered in the next decade", write Researchers, like Review of the technology reported online in "In Search of Planet 9".
In the last 20 years, astronomers beyond Neptune have discovered several small bodies, many with strongly elliptical orbits that lead them to the outermost areas of the Solar System, several hundred times farther away from the Sun than the Earth. These objects are found in a region known as the Kuiper belt. They are so small that they are easily influenced by the gravitational fields of their larger cousins, especially Neptune. Regardless of their orbits, they must be the result of forces exerted by larger planets.
Respecting all known limitations, Batygin and colleagues arrive at extremely precise conclusions about what kind of planet is searched and where to find it. Planet 9, they say, must have a mass between five and ten times that of the earth and surround the sun at a distance of 400 to 800 times greater than that of the earth; its orbit must have a slope of 15 to 25 degrees from the plane of the solar system, the magnitude should be between 19 and 24. "Such an object is easily observable with the current generation of telescopes with wide-angle cameras such as the Dark Energy Camera on the 4-meter Blanco telescope in Chile and the Hyper-Suprime camera on the Subaru telescope in Hawaii, "write Batygin and colleagues.
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