Black Hole Imaging
Very Long Baseline Interferometry (VLBI) is a technique in radio astronomy that involves observing astronomical objects simultaneously with radio telescopes separated by hundreds or even thousands of kilometers. By combining the signals recorded at each telescope, astronomers can computationally reconstruct images with extremely high angular resolution. In fact, VLBI delivers the highest angular resolution of any technique in astronomy. The Event Horizon Telescope (EHT) uses VLBI to capture unprecedented images of supermassive black holes at event horizon scales. Images of the 6.5-billion-solar-mass black hole at the center of M87 and the 4-million-solar-mass black hole at the heart of the Milky Way have already been published—both in total intensity and in polarized light. The EHT has also produced a series of images of nearby active galactic nuclei, which are shedding new light on the connection between black holes and the relativistic jets they power.
Building on the success of the Event Horizon Telescope, a new and more advanced array—known as the next-generation Event Horizon Telescope (ngEHT)—is currently under development. This upgraded instrument will include additional observing sites and expand the array’s frequency coverage. These enhancements will provide significantly improved angular resolution and sensitivity, and enable observations at the scales critical to understand jet launching processes. Learn more about the EHT and ngEHT by following the links below.
