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Why Did the Photo of the Black Hole Take So Long?

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Why Did the Photo of the Black Hole Take So Long? Over the past few weeks, the world has Why did the photo of the black been going crazy over the first photo of hole take so long? a black hole. What’s the big deal? Didn’t Photo me like one of ...no Interstellar do your French girls it first?* What makes this such an amazing feat? A poorly drawn comic by Mae Lee *an artist’s rendition that was pretty scientifically accurate! That type of resolution would need For starters, this black hole is 55 million light years a very large satellite dish. away. On top of that, black holes are very dense, so *earth for relatively speaking, they don't take up much space! scale How did I get here? Is Imaging it would be anyone coming to get like imaging an me? orange on the surface of the moon from earth! In fact, the satellite would have to Lonely Orange on the Moon be the size of the entire earth! Because we can’t do this, instead 8 smaller For example, satellites were built all around the world if the full by 2017. Together, these satellites are picture was called The Event Horizon Telescope, or this: the EHT. We might get this! Does that picture *not to make me look fat? scale ...Our bodies are literally 1 dimensional We can guess the missing pieces by making sure the image is continuous, but then we could get any of the following images. Because the EHT doesn’t cover the entire surface of the earth, it gives us bits and pieces of the final picture we have to link together. We can use machine learning to weight But we have to be careful! Because we don’t certain outcomes as more likely than know for sure what a black hole actually looks others: like, we don’t want to bias the outcome with Likely! Unlikely! what we think it looks like. For all we know, anything could be at the center > of the galaxy. A black hole? A space dolphin? A large bowl of Mac & Cheese? (one can only hope). We can check if our model is biased by feeding it different stores of images (which produces different biases) and see if it produces the same image. According to Dr. Katie Bouman, who wrote this algorithm, this would be like if we gave various sketch artists from all around the world the same descriptions of a person. If they all produce the same image, we can assume cultural bias is minimized! Back to the data taking! Over a few days in The answer to this question is that there was April 2017 in which conditions were optimal a lot of data. It was collected at around 64 for data taking, each location synchronized gigabytes/second, which is about 1000 times their clocks (tb to Phys 23!) to within a faster than standard home microsecond. internet. To the Cloud! Wait, if the algorithm was written in 2016 and the ...Please don’t 100s of data taken in 2017, why terabytes This pure volume of data are we just seeing this can’t be transferred over photo now? the internet! It takes time for this data to be After years of transferred physically all to the same Beep Beep! innovating, planning, location. And because of the Scientific and building, this volume, it takes an incredibly long discovery coming international effort time to parse through all of it and through! has produced a run it through the algorithm. This is scientific discovery why the photo of the black hole took of a lifetime! so long! Thanks for reading! .
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