[Epoch Times, July 07, 2022](The Epoch Times reporter Di Rui compiled and reported) Scientists have conducted the most accurate observations and analysis of the center of the Milky Way so far and found that the mass of the super black hole at the center of the Milky Way accounts for 99.9% of the total mass in this region. %.
In the very center of the Milky Way lies a super black hole, Sagittarius A* (Sgr A*), with a mass 4.3 million times that of the Sun. The discovery was awarded the 2020 Nobel Prize in Physics. But since then, astronomers have not been able to determine whether the total amount of matter there comes mainly from this black hole or from other things like stars, small black holes, interstellar dust and gas, dark matter, and what percentage of the total matter. .
The new study explored this question and found that up to 99.9% of the matter in the central region of the Milky Way comes from the Sagittarius A black hole. In other words, there are hardly any other celestial bodies in the central region of the Milky Way except this super black hole.
According to the study, Einstein’s theory of relativity believes that the orbits of stars orbiting supermassive objects are different from those calculated by Newton’s classical mechanics, that is, each orbit is not exactly the same and fixed. More specifically, the theory of relativity predicts that the orbits of stars orbiting super black holes will show a specific precession pattern, that is, the orbits of each orbit will be slightly different from the orbit of the previous one. Theory predicts that they will exhibit a lotus-like precession pattern, which scientists call Schwarzschild precession.
The study took a closer look at the orbital patterns of the four stars S2, S29, S38 and S55 orbiting closest to the Sagittarius A black hole. By analyzing the precession of their orbits, the mass distribution of Sagittarius A black holes can be inferred. The results show that the extra mass inferred from a little difference seen in the orbit of the S2 star is at most 0.1% of the mass of the Sagittarius black hole.
“Measuring subtle changes in the orbits of those distant stars orbiting the super black holes at the center of our galaxy is unimaginably difficult,” the team said in a press release announcing the results. “To make further discoveries, astronomers must not only challenge the The limit of scientific knowledge also needs to challenge the limit of engineering technology.”
What the researchers are referring to is that to complete such research, not only the precise calculation of difficult theories, but also the continuous improvement of the sensitivity of observational instruments is required to achieve more breakthroughs.
The research team hopes that the Giant Magellan Telescope (GMT) and the Thirty Meter Telescope (TMT), which are under construction, will be able to measure data from even lower-brightness stars with higher accuracy.
The research was published in the journal Astronomy & Astrophysics on January 19 this year. ◇#
Responsible editor: Ye Ziwei
