Yet Another Cycling Forum
General Category => The Knowledge => OT Knowledge => Topic started by: Canardly on 08 April, 2019, 08:55:45 pm
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Could not find this elsewhere. Photos are set to be released on Weds. What do people expect to see?
https://eventhorizontelescope.org/ (https://eventhorizontelescope.org/)
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Blackness. With artificial colouring.
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Holly: Well, the thing about a black hole - its main distinguishing feature - is it's black. And the thing about space, the colour of space, your basic space colour, is black. So how are you supposed to see them?
Rimmer: But five of them? How can you manage to miss five black holes?
Holly: It's always the way, innit? You hang around for three million years in deep space and there hasn't been one, then all of a sudden five turn up at once.
Pot noodles on standby...
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A rather hot event horizon, I'd imagine. Get out the marshmallows.
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A rather hot event horizon, I'd imagine. Get out the marshmallows.
TBH, I prefer mine merely toasted - the x-ray irradiation spoils the taste somewhat.
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X-rays. Pah. I prefer my marshmallows briefly toasted with a burst of ultra-high energy hard gamma rays. Serve with a hint of neutrino.
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Nothing from the Whitehouse as yet concerning biggest bestest ............
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Nothing from the Whitehouse as yet concerning biggest bestest ............
Busy filming the fast show.
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Nothing from the Whitehouse as yet concerning biggest bestest ............
Trump is a political black hole - people caught inside his event horizon suffer the complete destruction of integrity1 and reputation2, while in a reverse of how most black holes work, no data is able to penetrate.
1 Assuming that they had any to begin with.
2 In accordance with the Rick Wilson Rule: Everything Trump Touches Dies (ETTD).
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First photos have just come in
(https://amp.businessinsider.com/images/5ca8c277c6cc5038a41012d2-750-422.jpg)
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That looks like an artist's impression.
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Photos at 14:00 our time, today
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BBC Four are running a programme this evening at 9pm about the journey to capture these pictures, "How to See a Black Hole: The Universe’s Greatest Mystery"
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I was going to post a picture of Boston Lincs but thought I might get some ggggrrrrrssss from the locals!
Looking forward to the photos and wonder whether they will answer some fundamental questions such as are Black Holes hairy like Steven Hawking suggested.
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I was going to post a picture of Boston Lincs but thought I might get some ggggrrrrrssss from the locals!
Looking forward to the photos and wonder whether they will answer some fundamental questions such as are Black Holes hairy like Steven Hawking suggested.
As a Bostonian (but a Cestrian fo the last 40 years) why Boston? And I do agree with you, when I went to the Grammar School it was a fairly well-to-do market town, but over the last 20 years or so on visits to my late parents it really deteriorated. It's a bit of a dump now, especially along Spilsby Road.
My brother, who's a farm manager out in the Fens is shortly to retire, so he has to buy a house for the first time, and whilst he's well-off financially, he can't find anything in the town that he'd want to buy. Sad really, it used to be a lovely little Fenland town.
And it's not the migrant community, it's just a lack of investment and a loss of urban pride. And I don't know why; my Cheshire/Marches village home for the last 30 years hasn't gone the same way. Must be a lack of cash in the arable farming industry driven to the bottom by the buying power of the supermarkets, squeezing margins.
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Why Boston....well first is with regards to work so I regret I cannot say more and secondly, it was a dig at their anti EU stance. Sorry, it was a poor attempt at humour.
I have actually been there once....well I drove through the place on the way to somewhere else. For the life of me I can't remember where I was going!
How about I post a picture of Hadley Telford instead.... Surely no-one here lives in Hadley.....
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Ha ha! I can agree with you about bits of Telford!
Surprised you can't remember where you were going when you passed through Boston ;D. You don't go to Boston unless you are absolutely determined to go somewhere in that part of the country. It's off all the beaten tracks. Even Skeggy.
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It may have been Skeggy.... I've been twice on business. Quite nice, if flat, cycling around there.
The presentation is now on Youtube if anyone is interested in watching it live.
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https://www.bbc.co.uk/news/science-environment-47873592
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"measures 40 billion km across". Our Sun's diameter ~1.4 million km. :o
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The strange thing is that its density could be less than that of water.
https://en.wikipedia.org/wiki/Supermassive_black_hole
(Wiki were quick off the mark.)
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Veritasium has good video explaining what the image shows: https://www.youtube.com/watch?v=zUyH3XhpLTo
This video was made before the image was revealed so it also demonstrates the accuracy of the predictions
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The strange thing is that its density could be less than that of water
Volume is defined by event horizon radius so much within that volume will be empty space. Only at the centre is it super dense. So for super massive black holes the event horizon will be a super massive way out from the centre, super massive volume compared to amount of mass.
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Some good stuff from astrophysicist and "connoisseur of cosmic catastrophes" Katie Mack:
There's a brief write-up at @PhysicsWorld here: https://physicsworld.com/a/first-images-of-a-black-hole-unveiled-by-astronomers-in-landmark-discovery/ … with more images. Here's the image seen (left) compared with a simulation (middle) and the simulation blurred to the expected resolution of the telescope (right). (Image via Akiyama et al & ApJL)
https://pbs.twimg.com/media/D3y5h1lXoAEovA7.jpg
https://twitter.com/AstroKatie/status/1115971220762189824
If you want to dig into why the image looks the way it does, and what we're actually seeing, I have some suggested links for you! See next couple tweets.
Here's a page talking about creating simulated #BlackHole images: http://rantonels.github.io/starless/ Note: these renderings don't include the effect that makes the part of the disk moving toward us brighter (neither did the film Interstellar -- more about that here https://arxiv.org/pdf/1502.03808.pdf )
Here's a paper talking about the history of black hole images, with a detailed discussion of what you should expect for the "shadow" image we've just seen. Check Fig 12, with renderings of shadows for disks at different angles https://arxiv.org/pdf/1902.11196.pdf
Here's a technical paper from the @ehtelescope team talking about why the ring looks the way it does. Figure 1 showing the comparison between the image and the simulations is especially cool! https://iopscience.iop.org/article/10.3847/2041-8213/ab0f43
https://twitter.com/AstroKatie/status/1116024686893305861
Minor edit for speelung miss-toke.
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The strange thing is that its density could be less than that of water.
https://en.wikipedia.org/wiki/Supermassive_black_hole
(Wiki were quick off the mark.)
(https://upload.wikimedia.org/wikipedia/commons/a/af/Black_hole_-_Messier_87_%28cropped%29.jpg)
supermassive polo mint...?
cheers
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https://xkcd.com/2135/
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https://xkcd.com/2135/
Beat me to it!
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The strange thing is that its density could be less than that of water.
https://en.wikipedia.org/wiki/Supermassive_black_hole
(Wiki were quick off the mark.)
If only we had a pond big enough.
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I wonder to what extend using a hubble-like telescope / lunar based telescope in the EH telescope network would improve resolution...
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They're using the aperture synthesis technique developed for radio telescopy in the early 50s. I haven't read up on it for yonks, but I'd guess that a telescope in LEO wouldn't make that much difference, since it would only increase the baseline by (scope altitude)/(Earth diameter). A telescope on the moon would be more effective but out of eyeshot for 2 weeks every lunar month.
There's the problem of data-collation, too. The EH network gathered too much for electronic transmission: they had to store it on stacks of CDs/DVDs and send it for processing in crates.
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Thanks to DR. KATIE. BOUMAN !!
(https://pbs.twimg.com/media/D304hq_XkAAcXiv.jpg)
Reaction of Katie Bouman, who led the creation of an algorithm to produce first image of black hole.
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Some good stuff from astrophysicist and "connoisseur of cosmic catastrophes" Katie Macj:
There's a brief write-up at @PhysicsWorld here: https://physicsworld.com/a/first-images-of-a-black-hole-unveiled-by-astronomers-in-landmark-discovery/ … with more images. Here's the image seen (left) compared with a simulation (middle) and the simulation blurred to the expected resolution of the telescope (right). (Image via Akiyama et al & ApJL)
https://pbs.twimg.com/media/D3y5h1lXoAEovA7.jpg
https://twitter.com/AstroKatie/status/1115971220762189824
Yay, science! :)
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And it's only after someone quotes me that I spot the typo... ;D ::-)
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It is kinda scary and amazing that Einstein had this idea that it would look like this and then this many years later we have the tech to take a snap of it
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I can't help but think of
(http://www.dailyexcelsior.com/wp-content/uploads/2018/12/Blackhole-sonuts.jpg)
doughnuts....
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I can't help but think of
(http://www.dailyexcelsior.com/wp-content/uploads/2018/12/Blackhole-sonuts.jpg)
doughnuts....
Sprinkles!
I love teh look on her face of unbridled excitement.
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New BH photos. 5bn light years away. :o https://www.theguardian.com/science/2020/apr/07/scientists-capture-image-of-black-hole-emitting-high-energy-jets
(https://i.guim.co.uk/img/media/c371dd0b5c6545c5c4f6b78e77b3ea7d853965a2/0_57_1478_887/master/1478.jpg?width=620&quality=85&auto=format&fit=max&s=e9106067ec5a78e4cc5b73a4d1bf1948)
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Bottom left of that graphic: it's the right name but the wrong initials! :D