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Post by jandl100 on Jan 28, 2019 4:44:01 GMT
For the last couple of years the data analysis from high resolution imaging of our galaxy's central supermassive black hole has been underway. The far more massive central black hole of the nearby galaxy M87 has also been imaged as part of the project. en.wikipedia.org/wiki/Event_Horizon_Telescopeeventhorizontelescope.org/aboutIt's thought that the first images from the project are about to be released. Of course, many of us have already seen what a black hole surrounded by an accretion disc of infalling material looks like - in the film Interstellar. But as this article explains, that cinematic visualisation was deliberately simplified to make the image more comprehensible. www.sciencealert.com/black-hole-event-horizon-accretion-disc-jean-pierre-luminet-event-horizon-telescopeIn practise, the effects of an intense, light bending gravitational field should be far weirder. And one of the main things that groundbreaking scientific observations of the universe have taught us is to expect the unexpected. Exciting times. |
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Post by MartinT on Jan 28, 2019 7:39:57 GMT
Whatever you do, keep your distance!
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Post by MikeMusic on Jan 28, 2019 12:36:21 GMT
Read about this sort of thing in New Scientist.
Reminds me how small and insignificant we are in the universe.
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Post by MartinT on Jan 28, 2019 13:01:07 GMT
These supermassive black holes at the centre of galaxies defy any kind of reasoned thought. There is virtually nothing like their scale anywhere else in the universe. To then be told that ours is small compared with the one in M87 is virtually meaningless.
Which one would crush you more completely?!
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Post by Deleted on Jan 28, 2019 13:17:16 GMT
Arh, I see Roy Gregory's ego has escaped!
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Post by jandl100 on Jan 28, 2019 17:26:20 GMT
These supermassive black holes at the centre of galaxies defy any kind of reasoned thought. There is virtually nothing like their scale anywhere else in the universe. To then be told that ours is small compared with the one in M87 is virtually meaningless. Which one would crush you more completely?! Well, it matters to astrophysicists / cosmologists trying to understand how galaxies develop and evolve. "Our own" supermassive black hole is a mind-boggling 4 million solar masses, whereas the one tucked away inside the M87 galaxy is believed to be 3.5 billion solar masses i.e. a little shy of 1,000 times more massive. Sadly, the Milky Way is not well-endowed compared to other large galaxies. Which is curious in itself - I've not seen any research which addresses why this should be the case. |
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Post by jandl100 on Apr 1, 2019 19:21:05 GMT
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Post by MartinT on Apr 1, 2019 20:16:24 GMT
It's going to make us feel very small.
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Post by jandl100 on Apr 1, 2019 20:38:56 GMT
Actually, I'm not expecting a spectacular Interstellar-like cinematic image.
The resolution of the imagery given current technology is likely to be not a great deal finer than the probable size of the black hole's accretion disc - but you can do wonders with image processing these days, so it will be interesting to see what they come up with.
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Post by jandl100 on Apr 4, 2019 20:11:31 GMT
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Post by MartinT on Apr 4, 2019 20:19:10 GMT
Exciting!
I looked up that unit of arc...
1 microarc-second = 2.7777777777778 × 10-10 degree
So 50μas is a very small observed object (from here).
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Post by jandl100 on Apr 4, 2019 21:29:26 GMT
Yes, very small. That's why the Event Horizon Telescope will only get a fuzzy view despite being effectively the size of the Earth.
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Post by jandl100 on Apr 5, 2019 18:41:18 GMT
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Post by jandl100 on Apr 9, 2019 6:41:30 GMT
Interesting article from one of the astronomers who took part in the project. It includes practical details about the observing sessions and what being an astronomer is like. astrobites.org/2017/08/22/students-on-the-hunt-for-black-holes/?fbclid=IwAR1_Mw7DuDd_6X97VstLAb49pm1EW-kr6Iyo3mY-uJRnQbRsHdP7K1TIEiE... The Event Horizon Telescope is a network of eight millimeter-wave radio observatories located on four continents and representing over 20 nations. These observatories work together as a single Earth-sized telescope using the Very Large Baseline Interferometry (VLBI) technique. ... Each night, the LMT synchronized (with a precision higher than 10 -12 seconds) with the other telescopes using a hydrogen maser and recorded approximately 30 Terabytes of data WOW  |
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Post by MartinT on Apr 9, 2019 7:12:05 GMT
Each night?! That's a LOT of data to trawl through. Brilliant co-operative effort.
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Post by jandl100 on Apr 10, 2019 6:32:29 GMT
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Post by jandl100 on Apr 10, 2019 6:48:16 GMT
Here's a handy 4 minute video giving the technical background
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Post by MartinT on Apr 10, 2019 14:41:48 GMT
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Post by jandl100 on Apr 10, 2019 14:56:06 GMT
Wow.  |
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Post by jandl100 on Apr 10, 2019 15:45:17 GMT
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