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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.
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.
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).
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.
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.
The Tolmanâ"Oppenheimerâ"Volkoff limit is around 2.17 solar masses, or 4.3149799e30kg.
A typical LTO tape weighs about 200g. So 2.15748995e31, or 21 nonillion 574 octillion 899 septillion 500 sextillion tapes.
With a typical size of about 102x105x21.5mm you would end up with a sphere ~6.886e19m in diameter. Apparently LTO tapes are not very dense.
const int one = 65536; (Silvermoon, Texture.cs)
SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
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.