The EHT virtual telescope has a second scalp – our supermassive black hole
Our good old Sgr A *. Credit: EHT Collaboration.
–
The lazy monster in the heart of the Milky Way becomes a media star. Today, astronomers and all space explorers enjoyed simultaneous press conferences, which released the first image of our domestic supermassive black hole. This is fundamental evidence that the object known under the somewhat anemic name of Sagittarius A * is a supermassive black hole. This is only the second image of its kind, as in the first case, taken by the wonderful Event Horizon Telescope (EHT).
Horizon Telescope event. Yellow 8 original observatories, blue 3 new, added after 2018. Credit: ESO / M. Corn knife.
–
Finally, we see what the supermassive black hole of the Milky Way looks like, at least in the radio region of the spectrum. As has been said many times recently, we do not actually see a black hole as such, because it is really black and swallows all the radiation. The image shows a dark central area (shadow) surrounded by a glowing ring.
This image is, of course, affected by the brutal gravity of more than 4 million Suns. Geoffrey Bower of the Event Horizon Telescope project and Taiwan’s Institute of Astronomy and Astrophysics added that they and their colleagues were ecstatic to find out how well the size of the glowing ring in the image fits Einstein’s general relativity. At the same time, he is said to be very pleased with how these observations will deepen our knowledge of supermassive black holes and the environment at the centers of galaxies.
Comparison of images of both observed supermassive black holes. Credit: EHT collaboration.
–
The supermassive black hole of the Milky Way is about 27,000 light-years away. To give you an idea, the size of the ring captured in the image when viewed from Earth corresponds to the size of the donut lying on the surface of the Moon. Showing something like this wants a great idea. This was exactly the creation of the extremely powerful Virtual Telescope of the event horizon. It is known to combine the activities of originally 8 and now 11 radio telescopes, which are very powerful in themselves. The fact that one of the parts of the EHT is the famous ALMA system in the Chilean Atacama Desert speaks for itself.
The first supermassive black hole observed by the EHT telescope was the M87 * black hole at the center of the M87 galaxy. Now we have images of two galactic black holes and we can compare them, which is a cut, of course. A cursory glance at the images shows that the two supermassive black holes look similar, even though the M87 * is actually about a thousand times larger and more massive. According to scientists, this demonstrates the powerful power of general relativity, which provides an explanation for these objects.
The researchers claim that taking a picture of the supermassive black hole Sgr A * was significantly more difficult than with the black hole M87 *. The main reason is the much smaller size of Sgr A *. Gas orbits both black holes at a speed close to the speed of light. The black hole M87 * will circulate in days to weeks, but with our black hole Sgr A * it only takes a few minutes. Therefore, the brightness and gas arrangement at the black hole Sgr A * changes much faster, and these changes are very difficult to detect. As they would say in Gryffindor, it was like catching smoke. Catching smoke with bare hands.
Video: What it Takes to Image a Black Hole
Video: Size comparison of the two EHT black holes
Literature
–
