Most of us have seen quite a lot of celestial bodies, stars, almost any kind of interstellar cloud of dust, hydrogen, helium and other ionized gases… and, of course, black holes. We’ve seen it all, in all its shiny, colorful, amazing beauty. So we think.
Our ability to actually photoshop the universe has been done so masterfully that we almost got tricked into believing that something like a wormhole or even a black hole has been captured in pictures. In fact, these illustrations only represent what researchers have assumed black holes would look like!
Taking real pictures is a challenge we first have to tackle and now, thanks to a new algorithm, we could soon be staring at the real thing. Physicists from MIT and Harvard teamed up to develop this algorithm called CHIRP in an attempt to predict the parts of a black hole that radio telescopes failed to capture so far. In other words: we made one giant leap into taking direct images of black holes.
As it seems, black holes in particular are tricky monsters, as they are very far away and pretty compact. Lead researcher and MIT grad student Katie Bouman explains that taking a picture of the black hole at the center of the Milky Way galaxy is, “equivalent to taking an image of a grapefruit on the Moon, but with a radio telescope.”
This telescope needed would also need to have a diameter of at least 10,000 km (remember, the Earth’s diameter is scarcely 13,000 km). As Bouman is wisely thinking about a careful use of resources, there just needed to be another, more practical way.
Eventually the scientists from MIT and Harvard came up with a solution that uses an algorithm helping them uniting the massive data acquired by radio telescopes positioned all over the Earth to create an image of a black hole. This project bears the adequate name Event Horizon Telescope.
To get an idea of how a black hole looks in real life the team had to rely on the radio signals, as part of the black holes’ mystic lies in the absent of any visible light. Bouman got into more detail about the importance of the telescope saying:
“Just like how radio frequencies will go through walls, they pierce through galactic dust. We would never be able to see into the center of our galaxy in visible wavelengths because there’s too much stuff in between,”
The MIT was on board to help with the impressive technology needed as radio telescopes like the Event Horizon also require large antenna dishes. To overcome this, the team smartly decided to turn the whole Earth into an antenna dish itself by linking as many radio telescopes as possible in a technique that uses interferometry to combine data from around the world. By now, six observatories have already signed onto the Event Horizon Telescope project.
The next step is to firmly crab on Sagittarius A* at the center of the Milky Way called – our primary radio source and a supermassive black hole. All the data collected will be processed by CHIRP – the Continuous High-resolution Image Reconstruction using the algorithm. Chirp, so say the scientists, is intelligently “filling in” the parts of the black hole that weren’t captured by the telescope and thus, take a real snapshot.
In case you want to learn more about the joint project of the MIT and Harvard you can also get back to the Conference on Computer Vision and Pattern Recognition in Las Vegas.