Astronomers estimated the number of «dead stars» in the vicinity of the Sun

© Photo : Mark A. GarlickБелый dwarf — death star destroys him flying to the planetAstronomers estimated the number of «dead stars» in the vicinity of the Sun© Photo : Mark A. GarlickПодпишись to daily updates RIA Science

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. European probe»Stargazer» GAIA has calculated the number of white dwarfs in the immediate vicinity of the Sun and found hints that a quarter of them originated in the merger of two other «dead stars», what was previously a relatively rare event, according to Universe Today.

«Supernovae of the first type, resulting from mergers of white dwarfs, have already helped us figure out that the universe is expanding with acceleration. Despite this, we still do not know precisely where and how these are born of flash, and the pairing of white dwarfs. Us open traces the mergers of white dwarfs will help us to assess how often and where they occur,» says Mukremin Kilich (Mukremin Kilic) from the University of Oklahoma in Norman (USA).

White dwarfs are called the remnants of the old «burned out» stars with small masses, deprived of its own energy sources. White dwarfs occur at the final stage of evolution of stars with a mass not exceeding the sun more than 10 times. Ultimately, a white dwarf will become our light.

Such «dead stars» are interested in astrophysics for several reasons. First, they are the progenitors of supernovae of the first type, allows you to very accurately estimate distances in space, and secondly, they consist of exotic superdense matter properties and the structure of which scientists still do not fully understand.

And finally, thanks to the very long lifetimes of the white dwarfs can be used as a kind of «fossils», allowing astronomers to see what looked like our Galaxy or its neighbor in the distant past.

For this, according to Kilic, you must know one important thing – the exact distance to white dwarfs and their total number. The first is necessary for accurate assessment of their size and luminosity, and the second is to understand in what conditions they could arise.

Both these problems can be solved with the probe GAIA – a European probe, launched in 2013 specifically in order to determine the exact position and brightness of over a billion stars in the milky Way.

In April of this year, the GAIA science team published the first preliminary data directory, containing the coordinates and the description of these luminaries. This was used by Kilic and his colleagues to assess how many white dwarfs inhabits the nearest 300 light years from the Sun.

As it turned out, our light surrounds a lot of «dead stars» – 13928 white dwarfs, part of which lives in pair with normal lights or other compact objects. Because of this, according to Kilic, the number of known «dead stars» in the vicinity of our planet has increased by 30 times.

Conducting this «census», the astronomers noticed something unusual – it turned out that among them were unusual amounts of heavy bodies of similar mass to the Sun. In addition, the number of pairs of white dwarfs was much lower than scientists expected to see.

Both, according to Kilic and his colleagues explained the same thing – white dwarfs merge into each other more often than we used to think. How this happens is not clear, however, disclose a mechanism of combining them can radically change the picture of stellar evolution and our understanding of how frequent supernova explosions of the first type.

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