Astronomers now watching a distant star circling in a deadly dance around a large black hole. The distance between the objects is only approximately 2.5 times the distance between Earth and the Moon. Being so close to one of the deadliest of astronomical objects in the Universe, the star makes a full rotation around the black hole just half an hour. For comparison, a full turn around our comparatively small planet, our satellite, the moon takes about 28 days, while its speed is approximately 3683 kilometres per hour. All of this suggests that the star rotates around the black hole just the same at an insane speed.
On the basis of data collected by a network of telescopes used to study outer space, a team of astronomers had calculated the x-ray radiation created by double star system called 47 Tuc X9 located in one of the star clusters approximately 14 800 light years from us.
It Must be noted that the existence of this «couple» astronomers know already some time ago – the system was first discovered in 1989 — but only now scientists have a full picture of what is really going on.
"for a Long time it was thought that the X9 system consists of a white dwarf and sun-like companion star with a low mass that it sucks matter" — tells the researcher Arash Bahramian.
Typically binary system of stars with such temperamental relations belong to the category of cataclysmic stars. However, in 2015 it turned out that the companion white dwarf is a black hole, and not sun-like star, which in turn, forced scientists to reconsider some of the earlier hypotheses.
Returning to the study of this system, astronomers using the space telescope "Chandra" confirmed the presence near the star of a supply of oxygen. Previously, scientists have found white dwarfs with an oxygen atmosphere, therefore, no doubt, they were convinced that he had found the right target. However, instead of the expected picture where the white dwarf would tear apart another star, astronomers have witnessed the fact that the victim is a white dwarf, while the role of villain plays black hole, sucking out the gas.
By Themselves, white dwarfs are a type of superdense stellar objects, essentially representing the remains of stars (imagine an object with the mass of our Sun, but with the size of our Earth). Therefore, in order to extract from him the matter, you need to possess a really powerful force of gravity.
"We think that star was lost under the influence of the black hole stocks their gas over tens of millions in recent years and has now lost much of its mass," — says researcher James Miller-Jones from the Australian University kertina.
However, the most interesting news was related to the fact that on the basis of regular changes in the x-ray intensity of the star, scientists were able to establish that the white dwarf takes only 28 minutes to commit a complete revolution around the black hole, making it the champion among such "dirty dancing".
"Before this discovery, very close to the black hole star was the object located in the system MAXI J1659-152. Its orbital period is only 2.4 hours," — continues Miller-Jones.
If (and this really can be) both black holes in their systems have the same mass, the radius of the orbit of the star system MAXI J1659-152 is in this case, it is three times more than the star system X9. The distance between the objects in the system X9 is 1 million kilometers, which is approximately 2.5 times greater than the distance from us to the moon. Further calculations tell me the star for half an hour is a distance of approximately 6.3 million kilometers, which gives us the rate of 12 600 000 kilometers per hour. And this, in turn, is about 1 percent of the speed of light.
Despite the impressive numbers, article of researchers is currently still awaiting review by the community of physicists on the website arXiv.org. However, the information presented in it might be practical value in the future.
"the Opening of such a rare type of black holes is important, because they can not only tell us about the final days of the life of stars turning into supernova, but also because they continue to play its role in the evolution of other stars after his death," — comments Geraint Lewis of the University of Sydney.
Scientists say that our "space lovers" are not going to collapse in the near future and continue his dance of death without the convergence of the white dwarf to the belly of a black hole. Moreover, there is a suspicion that before both objects were closer to each other distance, or at least white dwarf had an even higher speed. For domination of the black hole's gravity above the gravity of the white dwarf must be closer to each other, but converge they do not intend. And yet over time, the whole material of the star in the end, no doubt, will be absorbed by the black hole, scientists say.
"In the end the white dwarf will lose so much matter that its mass will be equivalent to the mass of a normal planet," — says researcher Craig Heinke. – "If after this he will continue to lose mass, eventually completely evaporate".
For the scientists of the future, such news can not cause joy, as this will be an excellent opportunity for direct observation and study of gravitational waves. At the moment, even the most powerful laser interferometer laboratory for the observation of gravitational waves is not able to detect weak pulse, emitted by a star X9, however in the future technology will allow scientists to identify the waves of small frequency. Besides, no one denies the possibility that by that time we will be able to find more cataclysmic stars moving at even higher speeds....
Today we're looking at on the floating platform.
Today, March 14, Roscosmos began the selection of candidates in cosmonauts, writes TASS.
As reported by the news Agency «Xinhua», in Guizhou province, in southwest China, opened its doors to all comers, the world's largest radio telescope, the Five hundred meter Aperture Spherical Telescope (FAST or abbreviated).