American astrophysicists revealed the secret of the mechanism of formation of the so-called "new tidal stars", which presumably are many bright flash in the sky, observed since ancient times - for example, well-known star of Bethlehem. These "luminaries" born with a very strong convergence of two white dwarfs, make up a system.

It is believed that the so-called "new tidal stars" is not that other, as the end product of the interaction of a system of two stars, where one white dwarf, or rather, "thermonuclear burnt-out remains of a" normal stars (like our Sun), and the other is still a "traditional" main sequence star (or a red giant). Scientists suggest that if components such stellar pairs become very "close" to each other, the hydrogen from a normal star begins to flow to the surface more dense white dwarf. And when the concentration reaches a certain level, then thermonuclear reaction occurs, accompanied by an increase luminosity thousands (and sometimes even a million times.

Such stars, strictly speaking, a ' new tidal", it is easy to see from Earth. Astronomers have observed these phenomena in ancient times (532 years B.C. in China) and the middle Ages (1609-century - in the Western world). However, not always and not all of these outbreaks is developing in the above scenario. For example, in 2010 the American astronomers have noticed that one of these pairs reason intensively emits gamma radiation, which, according to current theoretical models, should be free.

And recently, a group of researchers from Cornell University (USA) under the supervision of Professor Jim fuller decided to look into the matter. The researchers conducted a simulation of a situation when a dual system are only two white dwarf, and ordinary stars are not near at all. The results showed interesting things: because of the high gravitational interaction in close systems outer layer of white dwarfs is heated by tidal interaction is much stronger than the inner layers. As well as these tidal forces are very high, because the dwarf is a star with a very high density, they find themselves in 10 thousand to 100 million times higher than the density of most heavy metals.

It is obvious that such a tidal waves carry a huge amount of energy, which leads to the colossal rise of temperature in the boundary layer of a star. And it contains a very small amount of star hydrogen (about 0.01 percent of the total mass "burnt" of light). However, under the action of tidal waves and this insignificant quantity is enough for spontaneous generation of thermonuclear reactions in a few points.

After these explosions, whose activity is similar to the work of detonators in explosive device, warm up and condense hydrogen beside him, the latter also explodes, starting new thermonuclear reaction. That is why we on Earth and see the increase luminosity is not as bright above objects. And because of this may occur and the mysterious gamma-radiation, which, as we remember, consists of high-energy photons, because it is a common companion powerful thermonuclear explosions.

According to astrophysicists, the final stage of the evolution of any pair of white dwarfs with the period of reciprocal treatment from 5 to 20 minutes is as follows: first, they will generate "new tidal star", and then, after about a hundred thousand to one million years it would merge into a single celestial body. That is, the model suggests that opened a new path of star formation and therefore a new type stars. Of course, this sensational statement by astrophysicists, but check his justice will be very difficult.

The matter is that according to the calculations of the group Jim fuller, such events occur in our Galaxy once every few decades, that is, it is quite rare. At the same time, scientists believe that, perhaps, education "new tidal" it happens more often, simply astronomers cannot accurately identify some similar events exactly how this process. Therefore, they proposed original method of discovery of this phenomenon at the earliest stages.

According to astrophysicists, before the beginning of thermonuclear explosions (and, consequently, a sharp increase in luminosity) of the place where it is assumed the appearance "tidal new", should not be an x-ray. Remember, this is usually caused by accretion (the process of falling matter in the cosmic body from outside) substances less dense stars on the surface of the white dwarf. Well, because in pairs without a normal star accretion does not happen (there's just nowhere to take the matter, which would fall onto the star, because they both have the same density and none of them can "steal" matter in another), there are no x-ray radiation.

That way, you can clearly separate the processes occurring in pairs of white dwarfs, from like, having a place to be in other star systems. At the same time, the authors draw attention to the fact that, according to their model, in a subsequent period, short-term growth luminosity "new tidal stars" its radiation can be different from the standard picture. That is, the probability of occurrence as gamma-ray bursts, and other streams of electromagnetic waves. However, do not be shy - after a few days the picture "is equalized" and a new star will not be puzzling astronomers its surprises...