One of the largest stars in the sky, the supergiant Betelgeuse, has a breakneck speed of rotation. According to scientists, this may indicate that a neighboring star was absorbed less than 100 thousand years ago. So - I took it and ate it …
Betelgeuse is a red supergiant on the right (for the observer - left) shoulder of Orion. This is one of the largest stars known to astronomers: according to various estimates, its diameter may be comparable to the orbit of Mars, and possibly Jupiter. Betelgeuse is extremely "loose", it is only 13-17 times heavier than the Sun, so that its brightness falls to the edges rather smoothly, making it difficult to accurately estimate the size.
At the same time, they are constantly decreasing: over the past couple of decades, the diameter of Betelgeuse has decreased by almost 20 percent. There is still no reliable explanation for this phenomenon, although it is believed that sooner or later it will end in a supernova explosion. This may happen tomorrow or in a thousand years - and it will become a grandiose (and completely safe) astronomical event. Well, in anticipation of this show, astronomers continue to study the unusual giant.
The new results, obtained by the team of the University of Texas astronomer Craig Wheeler, are being prepared for publication in the new issue of the Monthly Notices of the Royal Astronomical Society, but are already available on the ArXiv preprint service. With the help of computer simulations, scientists have refined the rotation of Betelgeuse, finding that here it does not behave like an ordinary supergiant. As a rule, as they increase in diameter, such stars slow down their rotation (like a skater extending his arms). Betelgeuse revolves around its axis 150 times faster than it should - the outer layers of the star are moving at an impressive speed of 15 km / s.
The work of Wheeler and his colleagues brought a new mystery to Betelgeuse, because there is no explanation for its accelerated rotation either. Scientists speculate that a nearby star, about the size of the sun, could have been the cause. Once it was near Betelgeuse, but it was absorbed by it in the process of growth and, together with its substance, transferred its impulse to the supergiant. If so, then this absorption should have been accompanied by the release of part of the substance. Calculations made it possible to roughly estimate the speed and time of this release - and calculate where this substance can be now. Indeed, Wheeler et al. Found that a cloud suitable for these parameters is observed in the images of Betelgeuse taken in 2012.