Why was it so hard to take a picture of a black hole?
Uhhhh this statement in the article about halfway down is incredible!<p>“You need to be able to tell the difference between one wave front and the next, and if the next wave front is 1.3 mm behind and traveling at the speed of light, then you need to reliably distinguishing between events 4 picoseconds apart (4 trillionths of a second).  So, every telescope needs a shiny new atomic clock and a really fast camera.  You begin to get a sense of why the data consolidation looks more like a cargo shipment than an email attachment; trillions of snapshots every second of not just the waves you’re looking for, but also the waves that will cancel out once all the data is processed.  Add to that the challenge of figuring out (generally after the fact) where every detector is to within a fraction of a millimeter even as their orientation changes and the Earth rotates, and you’ve got a problem.”<p>Just stupefyingly complex and amazing!