Harvard Will Test Whether Planet Nine Is A Miniature Black Hole
Astrophysicists from the United States have developed a technique that will allow them to find out whether the yet-undiscovered Planet Nine, the ninth world of the Solar system, is a miniature black hole, using the LSST survey telescope under construction, according to the press service of Harvard, referring to an article in the Astrophysical Journal Letters.
"Small celestial bodies, if they fall into the vicinity of a black hole, will begin to melt under the influence of heat, which produces gas falling on the event horizon. After that, they will be torn apart by the attraction of the black hole, which will lead to the birth of characteristic flashes of light," said Dr. Avi Loeb, a professor at Harvard University, whose words are quoted by the press service of the University.
Almost five years ago, two American planetary scientists, Konstantin Batygin and Michael Brown said that they had found the first traces of the existence of the mysterious Planet Nine. So scientists named the hypothetical ninth planet of the Solar system, distant from the Sun by at least 100 billion km and similar in size to Neptune or Uranus.
Its search has not yet brought success - researchers have only managed to narrow the area where it may be located, as well as find new hints of its existence. These failures led many astronomers to question the hypothesis, and other planetary scientists began to look for alternative versions of what Planet Nine might look like and where it really is.
For example, some astrophysicists now admit that Planet Nine may not actually be a gas giant, large Earth-like planet, or a "guest" from another star system, but a much more exotic object-the the so-called primordial black hole.
It is a miniature analog of ordinary and supermassive black holes, comparable in mass not to stars and galaxies, but planets. As cosmologists suggest, such black holes could appear in the first moments of the Universe's life due to the appearance of inhomogeneities in the distribution of matter across its space. The largest of them may have survived to the present day, gradually decreasing in size due to the formation of Hawking radiation.
Search for Planet Nine
Finding such objects, as Professor Loeb notes, will be even more difficult than searching for the classic Planet Nine. This is since such black holes themselves do not produce any radiation, unlike even the coldest and most inconspicuous planets.
Harvard astrophysicists found that they should still be visible to the most sensitive telescopes on Earth, paying attention to the situation in the part of the Solar system where the Planet Nine or primordial black hole is supposed to be located.
As scientists have noticed, they will be located at the point where the Sun's attraction will weaken so much that a primordial black hole the size of a planet will constantly attract the surrounding clusters of matter, including fragments of asteroids and comets that fill the outskirts of the Solar system.
As a result, according to scientists' calculations, the black hole will almost constantly generate miniature flashes of light, tearing apart objects whose diameter will range from a few centimeters to several hundred meters. These flares will be barely visible to existing ground-based telescopes, but they can be seen by the LSST Observatory under construction, located at the edge of the Atacama desert in Chile.
"The LSST Observatory has an extremely wide field of view, so it will receive images of the entire night sky twice a week. This is extremely important, given that we don't know exactly where Planet Nine is located. Besides, its high sensitivity will allow us to find traces of flares that produce even the smallest objects approaching the black hole," continues Loeb.
If the current theoretical assumptions are correct, then the LSST will detect traces of the existence of a black hole in the first three years of operation, provided that it is comparable to Jupiter in mass or significantly less than it. Otherwise, astronomers will prove that such objects do not exist in the Solar system, and also help theorists to impose stricter restrictions on the permissible masses of primordial black holes, which is extremely important for studying how the expansion of the Universe took place.