Black holes, being black holes, aren’t the easiest things to take pictures of. Not only are they black (absorbing nearly all the light that falls on them) , they also tend to be small, far away, and surrounded by things that are very very bright. The only way we’re going to get a good look at one from here is to use as large and sensitive a radio telescope as we possibly can, and the largest radio telescope you can possibly build on Earth is, well, a radio telescope the size of Earth itself.
This sounds a little nuts, but astronomers want to build a virtual Earth-sized radio telescope by linking together a bunch of different radio telescopes all over the world. They’re not going to try to fill in all the gaps (which ould involve covering most of the planet with antennas), but they don’t have to: thanks to a technique called Very Long Baseline Interferometry, an array of widely separated telescopes that are carefully synchronized can emulate (in some respects) one single telescope the size of the maximum distance between the farthest apart telescopes in the array.
via DVICE
Image credit: Wikipedia
