Planets larger than Earth can form around supermassive black holes

There is no doubt that one of the great developments in astrophysics in recent years is the discovery More than 5,000 exoplanets. Very different worlds have been discovered, from some who barely possessed the size of our moonand even many other times It is larger than Jupiterpassing through others very similar to Earth or Neptune, in addition to Super dust, rocky planets many times more massive than our planet. These planets were also discovered orbiting stars and Very different star systems. Some stars orbit single stars of different sizes, including red dwarfs like Proxima Centauri or TRAPPIST-1. Others revolve around it Double stars, with the planets where the double sunsets seen in Star Wars will be a reality. A planet the size of Neptune is known to revolve around two stars that are in turn part of a Quadruple star system.

Because of all the variety in the sizes and conditions of the planets that have been found so far, no one will be surprised by the new result obtained by a group of planets. Japanese researchersPlanets can exist (up to thousands of them) about supermassive black holes. However, the conditions surrounding a forming star and these extreme objects are not the same. Most large galaxies contain a Giant black hole At its center, which could be a mass between millions and many thousands a million times the mass of our sun. The gas disks that form around these massive black holes, as a result of the accumulation of large amounts of mass, emit large amounts of energy. This is actually what is known as a “active galactic nucleiOr AGNs for their English acronym.

Although the existence of these objects had been suspected for decades, due to the large concentrations of mass observed and the intense radiation emissions from the center of many galaxies, experimental confirmation came in 2019 when the science collaboration was in charge of the telescope. event horizon Post a picture of the object you are running The nucleus of the galaxy M87. What is seen in said image is actually radiation emitted by matter orbiting the black hole, which reaches temperatures where it can be emitted intensely. In addition to those hotter things, Large clouds of gas and dust They can surround these supermassive black holes, making it difficult for us to observe them directly. However, the planets could be exactly what formed in those clouds.

These planets got a name planets (as an abbreviation for Planet black hole And also to indicate that their position is very different from that of normal planets), they will start as Microscopic dust specks And they will end up getting sizes similar to those on Earth, located light years away from the central black hole. As in the protoplanetary disk from which planets are born around a forming star, the Low speed collisions These grains of dust allow them to stick together. And the larger it is, the more surface area it occupies, causing it to collide with more and more dust particles. It starts at about a centimeter in size Vacuum the surrounding dust. When it reaches a size of 100 meters, the small gravity of the protoplanets begins to shape the cluster, which until now has been held together by simple cohesive forces. These objects will continue to grow, depending on the amount of material they share orbit with, until they reach masses of up to 10 times the mass of Earthin orbits across several light years This takes more than 100 years to complete.

However, the researchers point out that the environment around a black hole, even light years away from the central body, could be very violent to favor the formation of planets and that the collision velocity of dust grains in the early stages of formation may be very high and instead of allowing them to aggregate, can destroy them. They also believe that observing these planets will be a real challenge. The usual methods of observing exoplanets should not suffice, at least not with the sensitivity we can achieve today. These techniques are taught, for example, very light wobble star due to the gravity exerted by or by the planet decrease in brightness It was discovered due to the transit of the planet in front of the star. according to emission fluctuation Of the active galactic cores, these technologies were unable to realize the insignificant contribution of a planet A billion times less massive from the orbiting black hole.

Of course the conditions on the surface of these planets They will not be fit for life at all. mainly for Very intense radiation emitted from the central region and surrounding regions of the black hole, which would prevent the development of complex chemistry, which is the first essential step for the development of biology. Moreover, such planets are likely to exist bombarded constantly with a large number of things, which makes its surface hell. Despite the fact that they cannot support life, observing and studying them can allow us to deepen our knowledge of the universe and the various processes that make it appear the way it is.

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