How Do You Photograph a Black Hole? The Telescope the Size of Earth Is Still Rewriting the Answer.
On April 10, 2019, the Event Horizon Telescope revealed the first image of a black hole: a lopsided orange ring around a dark shadow in the galaxy M87, 55 million light-years away. The image was not a photograph in any conventional sense. It was assembled from radio signals captured by dishes on four continents, synchronized by atomic clocks, and combined into a virtual telescope with the resolving power of a single dish the diameter of Earth. Here is how the impossible image gets made, why the Milky Way's black hole took three more years to resolve, and what the collaboration is still discovering about magnetic fields, relativistic jets, and the edge of spacetime.










