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The Black Hole Image Data Was Spread Across 5 Petabytes Stored On About Half a Ton of Hard Drives (vice.com)
An anonymous reader quotes a report from Motherboard: On Wednesday, an international team of scientists published the first image of a black hole ever. It looked like a SpaghettiO, and yet the image was an incredible scientific achievement that gave humanity a glimpse of one of the universe's most destructive forces and confirmed long-held theories -- namely, that black holes exist. Storing the raw data for the image was a feat itself -- tiny portions of data spread across five petabytes stored on multiple hard drives, the equivalent of 5,000 years worth of MP3s. Katie Bouman, a computer scientist and assistant professor at the California Institute of Technology, led the development of the algorithm that imaged the black hole. An image of her posing with some of the data drives went viral as observers praised her success.
The massive amounts of data were essential to creating the image of the black hole. Bouman and other scientists coordinated radio telescopes all over the Earth, each pointed at the black hole and gathering data at different times. The data scientists then pieced this information together and used an algorithm to fill in the blanks and generate a likely image of the black hole. The five petabytes of data took up such a massive amount of digital and physical space it couldn't be sent over the internet. Instead, the hard drives were flown to processing centers in Germany and Boston where the data was assembled. On Reddit's /r/datahoarder subreddit, a community dedicated to spreading the passion of hoarding vast amounts of data, the drives were bigger news than the scientific achievement itself.
The massive amounts of data were essential to creating the image of the black hole. Bouman and other scientists coordinated radio telescopes all over the Earth, each pointed at the black hole and gathering data at different times. The data scientists then pieced this information together and used an algorithm to fill in the blanks and generate a likely image of the black hole. The five petabytes of data took up such a massive amount of digital and physical space it couldn't be sent over the internet. Instead, the hard drives were flown to processing centers in Germany and Boston where the data was assembled. On Reddit's /r/datahoarder subreddit, a community dedicated to spreading the passion of hoarding vast amounts of data, the drives were bigger news than the scientific achievement itself.
Let's start measuring storage space by the ton! We can have Kilotons and Megatons...wait, that sounds very familiar...
"Never underestimate the bandwidth of a station wagon full of tapes hurtling down the highway." -- Andrew S. Tanenbaum
of a C130 loaded with Flashdrives flying at 700 mph. The latency is a bitch though.
**Life is too short to be serious**
Trying to look at star is also impossible because its surface masks everything underneath. And trying to look at a cup of coffee is also impossible because you're not really looking at the cup itself, just at the light which has reflected on it.
I can turn it upside down too: a black hole can be observed even better than a star because it doesn't have its own light so you can see the impact it has on its surroundings without interference from the central light source.
It's too much sophistry for me. You see a black hole because what it does with the things around it, and because you need a very busy place to create a big black hole you are going to see a lot of activity around it too once it's there.
And we are talking about radiotelescopes here. What you get is a signal from an antenna, and you have to recalculate the sources of the different waves the antenna recorded. The datapoints are just long lists of energy measurements from the different antennas.
We knew beforehand that M87 (a large eliptical galaxy about 55 million light years away) had a supermassive Black Hole at its center. There were estimates of its size from redshift measurements of the movements of the galaxy's center. Thus this is not a discovery we stumpled upon, this was a carefully selected target, and there were expectations beforehand how the picture should look like. A physicist who wrote his doctorial thesis on how a picture of a Black Hole should look like, gave a speech three month ago (albeit in German): Andreas Mueller: Foto eines Schwarzen Loches.
She clearly didn't write the majority of the code. However it's entirely possible she's responsible for the math and/or the actual algorithm the code implements. There's a system used at my company that I wrote relatively little of the code for (mostly low-level stuff like high-performance maths primitives and zero-copy networking), but I had a lot of input into the design and how it's supposed to achieve what it does. I don't know enough about this project to comment on whether Bouman is or isn't the brain behind it. I'm just saying that from experience, there are plenty of cases where the person who designed the algorithm isn't the person who ultimately implemented it. They might be a shitty coder, or just have other responsibilities.
Not valid unless given in LOCâ(TM)s
But what does the black hole sound like?
Yellow
Wanna buy a shirt?
https://www.redbubble.com/people/stealthfinger/shop?asc=u
From the movement of stars in the center of M87 you can calculate the mass of the center. The movement you can tell from the Doppler effect of their light. If they are moving to us, it is slightly shifted to the blue. If they move away from us, the light is redshifted. That's how you can tell the speed of the stars when circling the galactic center. From the distance to the center, you can tell the orbits. With the orbits and the speed, you know how much mass they are circling, because you can calculate the force that keeps them on their orbits. And when you get a mass of at least 4 billion times the mass of the Sun, you gotta ask which object has so much mass, especially if you don't see the light equivalent of 4 billion stars in the galaxy's center.
Here is a picture of M87 a.k.a. NGC 4486. It's not as if M87 was a totally unknown object before. You can see the large beam ejected from the center of the galaxy. It's about 5000 light years long and is caused by the magnetic field of the rotating Black Hole inside the galactic core of 87. The picture was taken by the Hubble Space Telescope (HST).
Erm...
I think you miss that this is a "real picture" of a black hole. It's black. That's the hole.
It bends space, time and light - correct. Anything past it's event horizon is lost forever, correct. But anything on the periphery isn't and arcs rounds and is fired back into space at random, almost... like a mirror. Light acts like a planet in orbit around the object, which means you can see all kinds of artifacts not caused by anything else, and can see light focused, diverted and spread from behind, in-front and the side of the object in question, producing bright halos of light - maybe from our own side of the galaxy - that orbited around the hole and came back our way.
And it's doing that in all dimensions. And depending on the tilt of the accretion disc, you'll see parts of that disc caught up in it / blocking light, which is why the halo isn't even - the accretion disc is tilted from our viewpoint.
Black holes are "invisible". But their presence makes everything near them go really weird and not like a standard piece of space at all.
You can even measure the Schwarzchild radius from the size of the haloes because parts of it will be directly related to certain multiples of the radius.
The black hole is only a point to us because it warps space, too. Whether it's actually a "point" in its local reference frame is another matter entirely.
She designed the algorithm. This does not necessarily relates to lines of code. Also eht-imaging is used for a wide area of applications. Mr. Chael is a PhD student at Harvard working on that piece of software. While Dr. Bouman performed the analysis and "developed the algorithm that turned telescopic data into the historic photo we see today". Here is her CV https://people.csail.mit.edu/k...
If Chael had done all this, his supervisors had claimed that or pushed that he would have been in the media.
Honestly, would you question her abilities if she would have been a male professor?
As someone who's entire job is taking scientist's algorithms and explaining them to computers, number of lines of code contributes has nothing to do with how much of the 'brains' one is behind something.
Yeah, there it is. Time for the whiny toxic manbabies to show up and cry about the evil woman. Fucking incels.
Manbabies don't know the difference. All they have is some dim recognition that being marginally competent and male is no longer enough to get by and scares the shit out of them.
The largest stars we know so far have masses of around 200 times the mass of the Sun, e.g. Eta Carinae. Eta Carinae has about 150 to 250 times the mass of the Sun, but it shines between 1,000,000 million to 5,000,000 million times brighter (the brightness actually fluctuates).
Sorry. 1,000,000 to 5,000,000 times or 1 million to 5 million times brighter. My bad.
In the end, we have a pretty good model which puts surface temperature, mass, brightness and lifetime of a star in a single formula. And it tells us, that large stars 10 to 20 times the mass of the Sun will burn through their fusionable material in very short time (1 to 10 million years). Stars even heavier will be unstable, as their emitted energy is not enough to keep the outer shells of the star from falling down into the core, heating it up even more and causing further fusion processes to start, which in turn will cause an explosion of the star. It gets much brighter, pushes its outer shells into space and then cools down, until the remaining star contracts again under its own weight, causing the core to heat up again. Thats why stars of the size of 80 to 200 times the mass of the Sun are called LBVs, Luminous Blue Variables. Because of their heat, they shine in a blue light, and they constantly blow up, reach their peak of brightness, explode, cool down, contract and heat up again.
Stars much larger would be so unstable, that they don't live long enough to be even called stars. They will just collapse under their own weight and turn their core into a neutron star immediately, as the pressure at their core is strong enough to destroy all the electron shells, and push the electrons into the cores, turning protons into neutrons. The energy released will pushing the complete outer regions of the stars into space in a big explosion.
TL;DR: The star becomes unstable and doesn't live very long.
"what if there is a star there which is 4k times our sun"
What if.. What if...
We actually LOOKED and there is no such star. There is a cloud-like disk with a black center. See picture in TFA.
"(the end and beginning of everything, where time exist and not exist, where your dreams become true, etc.)"
Where do you get this bullshit from???? Hollywood?
"your conclusions and assuming that something 4000 times more massive is likely to be much more brighter and to have a much stronger gravitational force, you move to "black hole""
We haven't seen a star that is 4000 times more massive than our sun anywhere in the universe.
This is one of the puzzle pieces. We see gigantic sources of gravity in very small volumes, but no star at the center. In fact, no light at all from the center.
This is what we observe.
Another piece of the puzzle is that our current theories also say the same thing. You can't make a star bigger than a certain size. If you try to do it you will concentrate so much mass in a small space that it will collapse into a small point and will trap light. So theory predicts there should be very massive and very small objects that look black to us.
So these theories explain and predict our observations.
"And why assuming a black or light-less or matter-less center rather than the much more logical tremendously bright and massive one?"
Again, we have never seen a star that is this big and bright. All stars that we have seen so far in our galaxy and in other galaxies are limited in size. Apparently the universe does not have big stars like you propose.
If you can find one they you will become a science superstar.
"Because a century-old theory (about which I will better not talk) told you so?"
Everything we have observed so far is exactly like that theory predicted. If you don't want to talk about it you will never understand why we expected black holes in the first place.
The theory says that mass bends space. We have observed this phenomenon without black holes. It is a true property of this universe.
Some smart person once noted that, according to this theory there can be a region of space where gravity is so strong that light can't escape it. A kind of black hole. That was about 100 years ago and at that time we had no instruments to observe such phenomena. So it was 'only' a theory.
Over the years, as our instruments became better and better, we started finding such regions of space. But we never could get a good picture due to limitations of our instruments. But it was enough to develop our theories more.
Now we have pointed our telescopes towards a place where the theories predict a black hole could be. And what do we find? A picture of a black hole surrounded by a fuzzy disk! It even includes other effects that the theory predicts, like that one side of the dust disk looks brighter.
So this picture is exactly like the 'old theory' predicted!
In over 100 years no one managed to create a different theory that predicted this picture.
Now, you could argue that the picture could be the result some other process. But then you would need to provide the mechanics of this other process. You have to make your own theory of why this picture looks like it does. :)
But then your theory will ALSO need to explain why GPS needs time correction, why stars behind the sun can be observed to the side of the sun and why light always travels at a single speed and hundreds of other effects that are explained by "the old theory".
Thousands of professional physicists haven't been able to create a different theory that explains all these effects.
So good luck trying to invent your own.
If you do not provide an alternative explanation that covers everything we have observed then you have no right complaining. You should first study the 'old theory' and try to understand why it has been so successful and no one has managed to invalidate it so far.
But think of it this way. If this 'old theory' wa
She designed the algorithm.
The NY Times says it wasn't the algorithm used to make the final picture. https://www.nytimes.com/2019/0...
While she led the development of an algorithm to take a picture of a black hole, an effort that was the subject of a TED Talk she gave in 2016, her colleagues said that technique was not ultimately used to create this particular image.
But that doesn't diminish her contribution to the project or her skills. She is clearly a skilled scientist but you have to read her actual articles to see that. By misrepresenting her role in the project you miss an opportunity to give her credit for the cool things she actually did. Not to mention the other 39 women and 160 men who also worked on the project.
All science is provisional, but some science is less provisional. Every test we've flung at general relativity over the last century has confirmed it. While it's not complete (Quantum Mechanics is not accounted for), it is as much settled science as one can get. Your problem is ignorance of how science works, coupled with pedantry, so that somehow you imagine you can usefully critique theories which you clearly know absolutely nothing about. You're arrogant and ignorant, but obviously not stupid, so instead of constructing versions of science that don't exist to cover up your lack of knowledge, just pick up some god-damned literature on the subject and fill the void that you have mistaken for intellectual curiosity.
The world's burning. Moped Jesus spotted on I50. Details at 11.
Which happens to look exactly how we'd expect to see the simulation that was done for Interstellar to look if we saw it from where we are, and with the equipment we have.
Honestly, you're directly getting photons for which the last thing they touched was a black hole 6.5 billion times the mass of the Sun, in the middle of another galaxy, 53.5m years ago, 53.5m light years away.
The picture isn't photographically beautiful because it never would be at those kinds of distances. That it even *exists* and produces anything at all is astounding.
I mentioned this in a late comment on the other post, and the hardware has been mentioned on the Reddit thread - including by the person who built the modules! - but the Mark 6 drive packs used for recording this data at various large, high-bandwidth radio observatories can handle 16 Gbps sustained records. (By way of comparison, an all-SSD RAID might get you about one-quarter that speed.)
It was explained to me by a guy who runs a radio telescope as each pack more or less being a JBOD, but with controllers smart enough to write each packet of data to whatever drive was ready to handle it, while keeping a journal on some other drive of where things had been written, so that the data could be reassembled later. The word "shotgun" figured into the explanation.
Village idiot in some extremely smart villages.
Gigagram is the correct SI unit for this.
You're not stupid, but you are ignorant. When you know enough to even ask sensible questions, and know enough to understand what is meant by "provisional" in science then maybe you can have a conversation. But you're pedantry and ignorance is just too much of an obstacle, and your thin skin just makes it all the worse.
The world's burning. Moped Jesus spotted on I50. Details at 11.
Chael has also come out and said that the software he worked on only has 68,000 lines of code in it anyway, and that he doesn't know, or care, how any of those lines were his.
The only thing necessary for evil to triumph is for it to be pitted against a slightly greater evil
She clearly didn't write the majority of the code.
However it's entirely possible she's responsible for the math and/or the actual algorithm the code implements.
From The internet’s idiots are already trying to discredit Katie Bouman’s historic accomplishments:
The criticism claiming Bouman is just one name of a few on the research paper shows a misunderstanding of how academic papers work. Bouman is the first author of her paper “Computational Imaging for VLBI Image Reconstruction.” The first author on a research paper is typically the person who made the most important contributions. Alongside Bouman, Michael D. Johnson, Daniel Zoran, Vincent L. Fish, Sheperd S. Doeleman, and William T. Freeman worked to produce their findings.
“Of course Bouman will not have written all of the code, just like Englert and Higgs are not solely responsible for the discovery of the Higgs boson. ..." Wade said.
In the discussion on Hacker News, and even in our own Facebook comment section, multiple users claim Bouman’s colleague Andrew Chael wrote over 850,000 lines of the 900,000 lines of code used to discover the black hole. Chael tweeted to her defense, saying that without Bouman and her contribution to the software, the project would never have been a success.
So, with respect to a successful outcome, does it really matter how *many* lines of code she (or someone) wrote, especially if her/their code and/or other contributions made everything work?
I imagine we've all heard the joke about getting an itemized bill like: $0.50: Pushing a button; $99.50: Knowing what button to push.
It must have been something you assimilated. . . .
Completely false. From Chael's own words:
BTW, Chael is gay. So congratulations on supporting him.
As to Bouman herself, she isn't the one taking credit. She has said repeatedly it was a collaborative effort:
So yeah it seems a lot of political science was involved here.
Sure was, it came from only one group who was so incensed a woman could do anything remarkable it had to jump up and down, wave its hands, and put out fake information to make itself feel better.
We will bankrupt ourselves in the vain search for absolute security. -- Dwight D. Eisenhower
Also:
But congratulations on supporting a gay guy in his efforts. I'm sure he's very pleased with your support. Now go scurry back to your white supremacist site with your tail between your legs because you played yourself.
We will bankrupt ourselves in the vain search for absolute security. -- Dwight D. Eisenhower
Following up whit this information from To undermine Katherine Bouman's role in the Black Hole photo, trolls held up a white man as the real hero -- until he fought back
The misleading posts said Chael alone had authored "850,000 of the 900,000 lines of code that were written in the historic black-hole image algorithm!" ...
However, the effort quickly backfired.
Though it may have been nice to receive more recognition, Chael immediately took to Twitter to explain that the online trolls had exaggerated his contributions, and he defended Bouman's work. In addition, Chael said that as an openly gay man, he is also an underrepresented demographic in STEM.
Chael disputed the incorrect posts
I did not write "850,000 lines of code" -- many of those "lines" tracked by github are in model files. There are about 68,000 lines in the current software, and I don't care how many of those I personally authored.
[... several tweets referenced ...]
While I appreciate the congratulations on a result that I worked hard on for years, if you are congratulating me because you have a sexist vendetta against Katie, please go away and reconsider your priorities in life.
Chael wrote the code for one of three scripted code pipelines that scientists used to transform telescope data into a coherent image.
Bouman has emphasized collaboration
Though Bouman has received a lot of attention, she has maintained that the black hole image was the product of teamwork.
"No one of us could've done it alone," Bouman told CNN. "It came together because of lots of different people from many backgrounds." The Event Horizon Telescope project was composed of an international team of more than 200 researchers.
It must have been something you assimilated. . . .
That you have to put down a woman who was instrumental in this magnificent feat of scientific endeavor says volumes about your insignificance on this planet. As Chael himself said:
Also, Chael is gay so I'm sure he appreciates your support, no matter how ill-founded.
We will bankrupt ourselves in the vain search for absolute security. -- Dwight D. Eisenhower
Well it was a team. I am sure it had women and men.
From How Katie Bouman Accidentally Became the Face of the Black Hole Project
As Dr. Bouman herself was quick to point out, she was by no means solely responsible for the discovery, which was a result of a worldwide collaboration among scientists who worked together to create the image from a network of radio antennas.
The project, led by Shep Doeleman, an astronomer at the Harvard-Smithsonian Center for Astrophysics, was the work of more than 200 researchers. About 40 of them were women, according to Harvard’s Black Hole Initiative.
Without knowing more about everyone on the team and who did what, etc... the rest of your speculations and commentary about "political science" in your post are pointless and/or counter-productive.
It must have been something you assimilated. . . .
That depends on what you mean by "led." She only committed about 0.4% of the actual algorithm code (affecting 3675 lines [github.com]), and many of those commits were for superficial things like the font color of the output. Other commits were to place other people's code into the project. The other 99.6% of the code was committed by men.
I've been on many some coding teams, and I will tell you that not many of my bosses contributed a single line of code. No one however will question whether or not they "led" the team.
She did not lead in the sense that she did not do most of the work, or most of the programming. Perhaps she was appointed to supervise the people who actually developed the algorithm, and in that sense she "led" the development.
No one has claimed she did ALL of the coding. Her claim is she developed the algorithm. According to Andrew Chael who wrote much of the code, you're just wrong.
So apparently some (I hope very few) people online are using the fact that I am the primary developer of the eht-imaging software library (https://github.com/achael/eht-imaging ) to launch awful and sexist attacks on my colleague and friend Katie Bouman. Stop.
Our papers used three independent imaging software libraries (including one developed by my friend @sparse_k). While I wrote much of the code for one of these pipelines, Katie was a huge contributor to the software; it would have never worked without her contributions and the work of many others who wrote code, debugged, and figured out how to use the code on challenging EHT data. With a few others, Katie also developed the imaging framework that rigorously tested all three codes and shaped the entire paper (https://iopscience.iop.org/article/10.3847/2041-8213/ab0e85 );
as a result, this is probably the most vetted image in the history of radio interferometry. I'm thrilled Katie is getting recognition for her work and that she's inspiring people as an example of women's leadership in STEM.
Well, there's spam egg sausage and spam, that's not got much spam in it.
And yet, you are so threatened by the idea that a women could be a talented scientist that you are projecting what YOU think by claiming its what he really thinks. Both of these young scientists are gifted contributors to the greater understanding of our universe who have BOTH stated they were mere members of a larger team. YOU however, are a coward hiding behind anonymity, terrified of anything that remotely impacts your false narrative of reality.
Dude, lay off the racism in your own statements. It's not helping anyone.
Also, not all white guys are racist, sexist homophobes.