An international team of scientists with the participation of employees of Moscow State University Lomonosov explained the structure of Saturn’s rings and modeled them into a supercomputer. This result can be applied to a variety of systems both in nature and in the industry.
An interesting question is why around some planets, such as Saturn, the rings appear, and others, from the same, say, Earth or Mars, the rings do not have? As it turned out, the size of the planet’s role does not play. The rings were found and the Giants, and even asteroids. An example of the latter – an asteroid with a diameter of Chariklo approximately 260 km, which in the past year, the Spitzer Space Telescope found just two rings.
In the answer to this question, at least approximately, there is: about one of the planets historically proved little dust and some other – a lot. Dust gathered together, formed particles which continue to grow and become more and more of that, of course, understandable. But why the particle growth suddenly stopped when they reached the size of a house? Here it remained a mystery.
Moreover, the very particle size distribution should have a beautiful mathematical law “inverse cube”, which means, for example, that the particle size of 2 m at eight times smaller than the size of the past 1 m, 3 m in size – less than 27 times, etc. The nature of this law also seemed mysterious.
An international team of researchers, which includes four Russians – a graduate of Moscow State University University Nicholas Diamonds (Professor of the University of Leicester, UK), Paul Krapivsky (professor at Boston University, USA) and researcher at the Department of Polymer and Crystal Physics Faculty of Moscow State University University Anna Bodrov Vladimir Stadnichuk, have finally clarify this issue by studying the particle size distribution in the rings of Saturn. During the work, the researchers showed that the observed distribution is universal, that is characteristic of all the rings that arise from the heavenly bodies, the particles of which have a similar nature. Furthermore, the scientists were able to unravel the mystery of the magic of the law “inverse cube.” The relevant article of the collective of authors, which includes Professor Frank Spahn (University of Potsdam, Germany), Jurgen Schmidt (University of Oulu, Finland) and Hisao Hayakawa (Kyoto University, Japan), published in the journal Proceedings of the National Academy of Sciences .
Saturn’s rings are a majestic sight. They consist mainly of ice crumbs, with small patches of minerals and extend for hundreds of thousands of kilometers away.
The “thickness of the rings”, ie their size in the other, perpendicular to, the direction – only 10-100 meters! In this sense, the rings of Saturn – a million times “thinner” the sharpest razor. In addition, the entire ice mass of rushing around Saturn with tremendous speed, 72 thous. Km per hour. This so-called orbital velocity with which the particles move as a unit. However, the velocity of individual particles still slightly differ from this average speed, but on average, these deviations are negligible – the order of several meters per hour!
As the particles fly up with each other at such low speeds, they are connected and can not fly away again because of surface forces – an effect similar to how two snow stick, providing them with the power to connect together. This process of coalescence of particles occurs constantly. However, there is an opposite process of destruction of the particle collisions. The fact that a very small fraction of the particles deviation from the average speed is significant.
If such a “fast” particle smashes into his “neighbor”, both crumble into small pieces. This happens very rarely, but eventually established balance between integration and disintegration of the particles.
Scientists have constructed a mathematical model of the processes that were studied by various methods, including a numerical solution to a huge number of differential equations. This can only be done on a supercomputer. The result has been involved one of the most powerful supercomputers in Europe – the MSU supercomputer “Chebyshev”. This part of the work was carried out Moscow colleagues research group. Scientists have explained how the absence of particles in Saturn’s rings more than a certain size, and a mysterious law of “inverse cube.” Moreover, because of the resulting model followed, and the important conclusion that these laws should be observed for all rings, whether it is a ring of the planet or asteroid.
According to the researchers, as, in particular, explained Anna Bodrov from Moscow State University, this universality is the only well-educated guess. In order to confirm or refute it, more research is required other rings.
This operation allows you to make a variety of other scientific findings – for example, the mechanism of formation of the rings and their evolution. In particular, the results of researchers suggest that the rings of Saturn are in steady state. This means that the dinosaurs were observed (if they could observe) the same ring that now. Those rings will monitor our descendants. Moreover, since the characteristic time of the change of rings under the influence of any external influences does not exceed 10 thousand. Years (this also follows from the model), nothing catastrophic happened to the ring since the Bronze Age.
At the time, the Nobel Prize winner Pyotr Kapitsa said that “there is nothing more practical than a good theory.”
This fully applies to this work. Researchers have developed a highly versatile mathematical tool that can be easily attached to a variety of systems both in nature and in the industry.
Wherever there is a system of particles that can stick together in collisions with low speed and break into small pieces at high speeds, there will be a particle size distribution, the next magical law “inverse cube.” 
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