Magnetar (in some sources "magnetar") is a neutron star that has a very strong magnetic field. Such a star appears as a result of the formation of a supernova. This type of star is extremely rare in nature. Not so long ago, the question of their finding and the immediate occurrence of astrologers exposed scientists to uncertainty. But thanks to the Very Large Telescope (VLT) located at the Panama Observatory in Chile, belonging to the European Southern Observatory, and according to the data collected with its help, astronomers can now safely believe that they have finally been able to solve one of the many mysteries so incomprehensible to us space.
As noted above in this article, magnetars are a very rare type of neutron stars, which have a tremendous strength (they are the strongest of the so far known objects in the entire Universe) of a magnetic field. One of the features of these stars is that they are relatively small in size and have an incredible density. Scientists believe that the mass of just one piece of this matter, the size of a small glass ball, can reach more than one billion tons.
This type of star can form when massive stars begin to collapse under the power of their own gravity.
Magnetars in our galaxy
The Milky Way has about three dozen magnetars. The object, studied with the Very Large Telescope, is located in a cluster of stars called Westerlund-1, namely in the southern part of the Altar constellation, which is located just 16 thousand light-years from us. The star, which has now become a magnetar, was about 40 × 45 times larger than our Sun. This observation confused scientists: after all, stars of such large sizes, in their opinion, should turn into black holes when they collapse. Nevertheless, the fact that the star previously named CXOU J1664710.2-455216, as a result of its own collapse, turned into a magnetar, tormented astronomers for several years. But still, scientists assumed that it preceded such a very atypical and unusual phenomenon.
Open star cluster Westerlund 1. The images show the magnetar and its companion star, torn away from it by the explosion. Source: ESO More recently, in 2010, it was suggested that the magnetar appeared as a result of close interactions between two massive stars. Following this assumption, the stars turned around one another, which caused the transformation. These objects were so close that they could easily fit into such a small space as the distance between the orbits of the Sun and the Earth.
But, until recently, scientists dealing with this problem could not find any evidence of the mutual and so close coexistence of two stars in the proposed model of a binary system. But with the help of the Very Large Telescope, astronomers were able to study in more detail the part of the sky of interest in which there are star clusters and find suitable objects whose speed is high enough ("runaway" or "runaway" stars). According to one theory, it is believed that such objects were thrown from their home orbits as a consequence of the explosion of supernovae that form magnetars. And, in fact, this star was found, which scientists later named Westerlund 1? 5.
The author who published the research data, Ben Ritchie, explains the role of the found "running" star as follows: “Not only does the star we have found have a colossal speed in motion, which may well have been caused by a supernova explosion, so here it seems to be a tandem of its surprisingly low mass, high luminosity and its carbon-rich components. This is surprising, because these qualities are rarely combined in one object. All this testifies to the fact that Westerlund 1 × 5 could actually have formed in a binary system."
With the data collected about this star, the astronomers' team reconstructed the supposed model for the magnetar's appearance. According to the proposed scheme, the fuel reserve of the smaller star was higher than that of its "companion". Thus, the small star began to attract the upper balls of the large one, which led to the integration of a strong magnetic field.
After some time, the small object became larger than its binary companion, which caused the reverse process of transferring the upper layers. According to one of the participants in the experiment, Francisco Najarro, these actions of the investigated objects exactly resemble the well-known children's game "Pass to another". The goal of the game is to wrap an object in several layers of paper and hand it over to a circle of children. Each participant must unfold one layer of the wrapper, while finding an interesting trinket.
In theory, the larger of the two stars turns into the smaller one and is thrown out of the binary system, at the moment the second star quickly turns around its axis and turns into a supernova. In this situation, the "running" star, Westerlund 1 × 5, is the second star in the binary pair (it carries all the known signs of the described process). Scientists who studied this interesting process, based on the data they collected during the experiment, came to the conclusion that very fast rotation and mass transfer between binary stars is the key to the formation of rare neutron stars, also known as magnetars.
Neutron star. Pulsar:
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