The consensus among the scientific community is that black holes are real. However, we have never actually seen one. Their existence was predicted by Einstein’s theory of relativity and subsequent measurements concerning the speed of orbiting stars and gravitational waves have provided strong corroboration. Astronomers may finally be on the cusp of getting their first photographic glimpse of a black hole—a direct view of the space-time crushing monster from the heart of galaxy M87.
On Wednesday, astronomers across the globe will hold “six major press conferences” simultaneously to announce the first results of the Event Horizon Telescope, when they are expected to unveil the first-ever photograph of a black hole.
The effort conscripted a team of astronomers from around the world and an interconnected web of telescopes known as the Event Horizon Telescope (EHT). These telescopes collectively have the strength to peer far enough into the core of the Milky Way to collect visual data from Sagittarius A, which has the mass of four million suns. With a five night window of viewing earlier this month—which was dependent on weather conditions—the Event Horizon Telescope observed the millimeter radio waves emanating from Sagittarius A.
Once the images are received, scientists will have to aggregate an enormous amount of data—which is likely happening at this very moment—using a technique called interferometry, equivalent to using about ten thousand laptops, to combine radio waves.
Since black holes emit no light, they can’t directly be seen, but astronomers expect the resulting image to basically be the shadow of a black hole reflected off its super-heated accretion disk—which should look something like an asymmetrical halo of light surrounded by a dark circle.
While the image will be haunting and incredible in its own right, the knowledge gained may be more important. A direct visual observation of a black hole, even though it’s only the shadow, could help answer the question of whether general relativity breaks down close to a black hole. If the image suggests as much, it could provide evidence for alternative theories of gravity and potentially progress toward resolving some of the contradictions between relativity and quantum theory.
The image—which astronomers have been attempting to capture for a decade—could also help answer whether or not pulsars orbit black holes and how their accretion disks eject vast jets of subatomic particles.
Astrophysicist Thomas Krichbaum of the Max Planck Institute for Radio Astronomy says understanding the nature of black holes will have crucial ramifications. “It is important to understanding the evolution of galaxies, from the early formation of black holes to the formation of stars and later to the formation of life,” he says. “This is a big, big story. We are just contributing with our studies of black hole jets a little bit to the bigger puzzle.”