With the number of fancy graphics, simulations and depictions in movies, it’s easy to think that we know exactly what a black hole looks like, but it turns out we don’t. There has never been one single real image of a black hole. But a team from MIT and Harvard have developed an algorithm that might enable us to see one for the very first time; all it will take is turning the entire planet into a radio telescope dish.
So what exactly is so difficult about photographing a black hole, and why has it never been done? As Katie Bouman, an MIT graduate student in electrical engineering and computer science, who led the development of the new algorithm, explained in a statement:
A black hole is very, very far away and very compact. It’s equivalent to taking an image of a grapefruit on the moon, but with a radio telescope. To image something this small means that we would need a telescope with a 10,000-kilometer diameter, which is not practical, because the diameter of the Earth is not even 13,000 kilometers.
But Bouman has devised a solution that just might work, an algorithm called CHIRP, for Continuous High-resolution Image Reconstruction using Patch priors. This algorithm would stitch together data that is gathered from radio telescopes from around the Earth by the Event Horizon Telescope Project.
Currently EHT draws together information from its array of radio telescopes, and these telescopes can penetrate galactic dust and provide us with pretty detailed images of the cosmos. But it has one significant problem when it comes to photographing a black hole; that galactic dust and dirt and debris slows down signals and causes information to arrive with variable delays. When pieced together, these images form a mosaic, and other algorithms to tie data together create something of a blur.
Bouman has developed an algebraic solution to this problem that has already been proven to filter out dust and fill in gaps of missing data better than any other algorithms out there. And so far six observatories have signed on to participate in EHT’s efforts to utilize the algorithm to capture the our first ever image of a black hole, and more observatories are expected to follow.
And this could ultimately provide us with something far more impressive than any artist’s rendition. As Michael Johnson, who worked with Bouman, told Popular Science:
Ultimately we might be able to make movies of materials being eaten by a black hole.