Very interesting. The previously-released M87 image had just a single "shadow", but this one (of Sag A*) has multiple bright "lumps". Maybe it's in the linked papers which I haven't gotten to yet, but why the difference? Is it due to the observation method or does it reflect a real difference? Or both?
Astronomers reveal first image of the black hole at the heart of our galaxy
21–30 of 329 posts
Re: Astronomers reveal first image of the black hole at the heart of our galaxy
#22One of the findings they announced at the press conference is that the spin of the black hole is not aligned with the galactic plane but is tilted "towards us" so that it is viewed face on. How unexpected is that?
[deleted]
Re: Astronomers reveal first image of the black hole at the heart of our galaxy
#23> “We were stunned by how well the size of the ring agreed with predictions from Einstein’s Theory of General Relativity," And ten thousand physicists sighed disappointingly.
Just curious but why?
Sometimes physicists like the theories--especially the battle-tested ones--proven wrong so that those theories needs to be refined or reevaluated. Something related to the joy of problem solving.
Re: Astronomers reveal first image of the black hole at the heart of our galaxy
#24This image apparently has not captured as much attention as the image of M87, but anyway, I have a question, maybe someone with the knowledge can answer:
Between the images of M87 and Sgr A, one noticeable difference is that the image of M87 appears to have a single cluster of light "below" the blackhole whereas the image of Sgr A has three surrounding the blackhole. Is this because of the mass and spin differences between the two blackholes?
Re: Astronomers reveal first image of the black hole at the heart of our galaxy
#25ithought this was old news from couple of years ago, did i miss something?
The previous image was of M87.[1] The new one is of Sagittarius A*, which is the black hole at the center of our own galaxy.
[1] https://www.nasa.gov/mission_pages/chandra/news/black-hole-i...
Re: Astronomers reveal first image of the black hole at the heart of our galaxy
#26There seem to be numerous submissions of this topic.
This thread seems to be the leading one:
Astronomers Reveal First Image of the Black Hole at the Heart of Our Galaxy
https://public.nrao.edu/news/astronomers-reveal-first-image-... (https://news.ycombinator.com/item?id=31353677)
Others, as of submitting this comment:
https://www.eso.org/public/news/eso2208-eht-mw/ (https://news.ycombinator.com/item?id=31353692)
https://public.nrao.edu/news/astronomers-reveal-first-image-... (https://news.ycombinator.com/item?id=31353677)
https://www.youtube.com/watch?v=rIQLA6lo6R0 (https://news.ycombinator.com/item?id=31353643)
https://www.youtube.com/watch?v=4Ws0iPDSqI4 (https://news.ycombinator.com/item?id=31353587)
https://www.nsf.gov/news/news_summ.jsp?cntn_id=305028&org=NS... (https://news.ycombinator.com/item?id=31353583)
https://nitter.kavin.rocks/ehtelescope/status/15247172729037... (https://news.ycombinator.com/item?id=31353547)
https://www.cnet.com/science/space/watch-live-astronomers-re... (https://news.ycombinator.com/item?id=31353480)
https://beta.nsf.gov/blackholes (https://news.ycombinator.com/item?id=31353474)
https://www.youtube.com/watch?v=rIQLA6lo6R0 (https://news.ycombinator.com/item?id=31353463)
https://www.nsf.gov/news/news_summ.jsp?cntn_id=305148 (https://news.ycombinator.com/item?id=31353757)
https://eventhorizontelescope.org/blog/astronomers-reveal-fi... (https://news.ycombinator.com/item?id=31353786)
https://www.nytimes.com/2022/05/12/science/black-hole-photo.... (https://news.ycombinator.com/item?id=31353823)
https://www.quantamagazine.org/black-hole-image-reveals-sagi... (https://news.ycombinator.com/item?id=31353874)
https://www.bbc.co.uk/news/science-environment-61412463 (https://news.ycombinator.com/item?id=31353939)
Re: Astronomers reveal first image of the black hole at the heart of our galaxy
#27ithought this was old news from couple of years ago, did i miss something?
[deleted]
Re: Astronomers reveal first image of the black hole at the heart of our galaxy
#28Very interesting. The previously-released M87 image had just a single "shadow", but this one (of Sag A*) has multiple bright "lumps". Maybe it's in the linked papers which I haven't gotten to yet, but why the difference? Is it due to the observation method or does it reflect a real difference? Or both?
[deleted]
Re: Astronomers reveal first image of the black hole at the heart of our galaxy
#29I am very skeptical of the Event Horizon Telescope (EHT) images because they are not following a scientific method that results in a true representative image of their target. In my opinion astronomy is jumping the shark with these images by making this a big PR stunt.
I've looked at their methods for their earlier images and they seem to be hunting for a circle that looks like a black hole in their data. The EHT's full imaging stack has never been calibrated by looking at a known celestial body to compare images to validate their algorithms. They have calibrated their signals from results of other instruments, but their imaging algorithms change to fit their wanted results. This is my biggest problem with their approach. Anyone can modify algorithms of any arbitrary data to get an image of a glowing circle. A better method that shows a more true image would be to calibrate their imaging algorithms against a known celestial body to make sure their techniques produced comparable results from other instruments. Then they should have taken their calibrated imaging algorithms and gave it data from their target.
I'd have more confidence in the EHT if they would not change their imaging algorithms across images and give a side-by-side comparison of a known celestial body that other radio telescopes have imaged to verify their whole imaging stack.
To me this a just a big PR stunt and I'm very skeptical of their image.
Re: Astronomers reveal first image of the black hole at the heart of our galaxy
#30Earlier quoted context omitted.
Just curious but why?
GR and quantum field theory don't work together, so at least one of them is wrong, and it would be good to figure out which and how.
You're saying this team has proven neither of them wrong in that their findings agree with GR, is that correct? Essentially, nothing new has been learned about these two theories?