Genady Posted May 10, 2022 Share Posted May 10, 2022 "Until May 12 rolls around, we won't know with any certainty what exactly it is that the NSF is going to announce." The US National Science Foundation Has 'Groundbreaking' News About The Milky Way (slashgear.com) 1 Link to comment Share on other sites More sharing options...
Genady Posted May 12, 2022 Author Share Posted May 12, 2022 WATCH LIVE: Astronomers reveal ‘groundbreaking’ findings about the Milky Way | PBS NewsHour Link to comment Share on other sites More sharing options...
Phi for All Posted May 12, 2022 Share Posted May 12, 2022 Very impressive work! Lots of new data to analyze. I wouldn't think it's very likely that, if our SMBH has a "jet" like M87, that it's pointing right at us so we can't see it, but it's certainly possible. Quite a coincidence, though. Link to comment Share on other sites More sharing options...
Genady Posted May 12, 2022 Author Share Posted May 12, 2022 50 minutes ago, Phi for All said: Very impressive work! Lots of new data to analyze. I wouldn't think it's very likely that, if our SMBH has a "jet" like M87, that it's pointing right at us so we can't see it, but it's certainly possible. Quite a coincidence, though. The jet should be perpendicular to the accretion disk plane, I think. I suppose they know that plane now. Maybe. Link to comment Share on other sites More sharing options...
StringJunky Posted May 12, 2022 Share Posted May 12, 2022 (edited) WASHINGTON (AP) — The world got a look Thursday at the first wild but fuzzy image of the supermassive black hole at the center of our own Milky Way galaxy, with astronomers calling it a “gentle giant” on a near-starvation diet. Astronomers believe nearly all galaxies, including our own, have these giant black holes at their center, where light and matter cannot escape, making it extremely hard to get images of them. Light gets chaotically bent and twisted around by gravity as it gets sucked into the abyss along with superheated gas and dust. The colorized image unveiled Thursday is from the international consortium behind the Event Horizon Telescope, a collection of eight synchronized radio telescopes around the world. Previous efforts had found the black hole in the center of our galaxy too jumpy to get a good picture. https://apnews.com/article/black-hole-milky-way-image-e482ee7b773b1053bcb296bbd9abea16 Edited May 12, 2022 by StringJunky 2 Link to comment Share on other sites More sharing options...
joigus Posted May 12, 2022 Share Posted May 12, 2022 On 5/10/2022 at 3:16 PM, Genady said: "Until May 12 rolls around, we won't know with any certainty what exactly it is that the NSF is going to announce." The US National Science Foundation Has 'Groundbreaking' News About The Milky Way (slashgear.com) Thanks! Link to comment Share on other sites More sharing options...
joigus Posted May 12, 2022 Share Posted May 12, 2022 Thanks. Merging suggested: 1 Link to comment Share on other sites More sharing options...
keremspace Posted May 12, 2022 Share Posted May 12, 2022 "Getting to this image wasn't an easy journey," Özel said. "It took several years to refine the image and confirm what he had." That was a huge step for science history. 1 Link to comment Share on other sites More sharing options...
StringJunky Posted May 12, 2022 Share Posted May 12, 2022 4 hours ago, joigus said: Thanks. Merging suggested: What does the 3 localized density gradients suggest to you, does it mean anything? Link to comment Share on other sites More sharing options...
joigus Posted May 12, 2022 Share Posted May 12, 2022 6 minutes ago, StringJunky said: What does the 3 localized density gradients suggest to you, does it mean anything? To my --totally untrained in interpreting astrophysical data-- eyes, I would say accidental changes in density in the accretion disc are to be expected. From the video talk that @Genady linked to, the experts make more of an issue of the way in which those gradients move --than of the fact that they're there at all--, if I understood correctly. The more mathematical-physicist type that talks there --Ziri Younsi-- states that all observations agree with Einstein's version of GR impressively well. The 'groundbreaking' part of it is more due to the achievement than to any big surprises, I think. 1 Link to comment Share on other sites More sharing options...
Genady Posted May 12, 2022 Author Share Posted May 12, 2022 In some other report I read that gas orbits the BH in minutes, much shorter than the observation time used to create this image. In any case, I understand that what we see is not the accretion disk, but its image distorted by the BH. E.g. the source of the bright spots maybe behind the BH and we see it three times as its light is lensed by the BH. 2 Link to comment Share on other sites More sharing options...
beecee Posted May 12, 2022 Share Posted May 12, 2022 1 hour ago, joigus said: The more mathematical-physicist type that talks there --Ziri Younsi-- states that all observations agree with Einstein's version of GR impressively well. Great stuff! hope some of our anti relativists are taking note. 1 hour ago, joigus said: The 'groundbreaking' part of it is more due to the achievement than to any big surprises, I think. That's the way I read the report also. The following is an interview with Professor Katie Bouman. Bouman spoke with AFP shortly after the breakthrough announcement. https://phys.org/news/2022-05-milky-black-hole.html Why was it harder to see Sagittarius A*?— "We collected the data for both M87* and Sgr A* in the same week in 2017, but it took us so much longer to make a picture of Sgr A* than M87*. "Sgr A* has a lot of other things that are going on that make it a lot more challenging for us to make an image. We're actually observing the black hole through the plane of the galaxy. And that means that the gas in the galaxy actually scatters the image. It makes it look like we're looking at the black hole through, like, a frosted window, like in a shower. That's one challenge. "But I would say the biggest challenge that we face is the fact that the black hole is evolving really quickly. The gas in M87* and Sgr A* is moving at roughly the same speed. But whereas it takes days to weeks to make a full orbit around M87*, for Sgr A*, it's evolving from minute to minute." 1 Link to comment Share on other sites More sharing options...
joigus Posted May 12, 2022 Share Posted May 12, 2022 1 hour ago, Genady said: In some other report I read that gas orbits the BH in minutes, much shorter than the observation time used to create this image. In any case, I understand that what we see is not the accretion disk, but its image distorted by the BH. E.g. the source of the bright spots maybe behind the BH and we see it three times as its light is lensed by the BH. Totally spot on. In fact, part of the light that we see is just behind the BH from the observer. The back of the BH from the observer may be the worst place to try to hide from them. Link to comment Share on other sites More sharing options...
joigus Posted May 13, 2022 Share Posted May 13, 2022 10 hours ago, beecee said: Great stuff! hope some of our anti relativists are taking note. That's the way I read the report also. The following is an interview with Professor Katie Bouman. Bouman spoke with AFP shortly after the breakthrough announcement. https://phys.org/news/2022-05-milky-black-hole.html Why was it harder to see Sagittarius A*?— "We collected the data for both M87* and Sgr A* in the same week in 2017, but it took us so much longer to make a picture of Sgr A* than M87*. "Sgr A* has a lot of other things that are going on that make it a lot more challenging for us to make an image. We're actually observing the black hole through the plane of the galaxy. And that means that the gas in the galaxy actually scatters the image. It makes it look like we're looking at the black hole through, like, a frosted window, like in a shower. That's one challenge. "But I would say the biggest challenge that we face is the fact that the black hole is evolving really quickly. The gas in M87* and Sgr A* is moving at roughly the same speed. But whereas it takes days to weeks to make a full orbit around M87*, for Sgr A*, it's evolving from minute to minute." Thanks. Very interesting! Link to comment Share on other sites More sharing options...
beecee Posted May 13, 2022 Share Posted May 13, 2022 A suggestion. In this age of political correctness, I recommend that we drop the name "Black Hole" to a more acceptable and correct title, such as "Gravitationally Completely Collapsed Object" or a GCCO ☺️ Link to comment Share on other sites More sharing options...
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