Today, the entire world witnessed the first image of a black hole, taken by the Event Horizon Telescope (EHT) project. This is a historic event, an important step in cosmology. We invite you to discover this special event through the article published on the official website of the EHT project:
Telescope Event Horizon (Event Horizon Telescope-EHT) is a planetary-scale telescope chain, including eight ground-based telescopes, designed to image black holes. Today, at an international press conference, EHT researchers revealed that they have successfully captured the first direct imaging evidence of a supermassive black hole and its shadow.
Galaxy M87. Photo: APOD
This historic achievement was announced today in a series of six papers published in a special issue of The Astrophysical Journal Letters. The image revealed the black hole at the center of the M87 galaxy, a massive galaxy located in the Virgo Cluster. This black hole is 55 million light years from Earth and weighs 6.5 billion times that of the Sun.
The EHT linked telescopes around the world to create a virtual, Earth-sized telescope with unprecedented sensitivity and resolution. The EHT is the result of many years of international collaboration and offers scientists a new way to study the strangest objects in the Universe, predicted by Albert Einstein’s theory of general relativity, marking the hundredth anniversary of the first historical experience confirming this. theory.
The network of telescopes that make up the EHT are located in many locations around the world. Photo: Harvard University
The EHT Project Director, Mr. Sheperd S. Doeleman, works at the Center for Astrophysics | Harvard and Smithsonian stated: “We took the first photo of a black hole. This is an extraordinary scientific feat carried out by a team of more than 200 researchers.
Black holes are unusual cosmic objects with enormous mass but limited size. The presence of these objects affects their surroundings in strange ways, such as by distorting space-time and heating any surrounding matter.
“If in a bright region, such as a disk of glowing gas, we would expect the black hole to cast a dark shadow-like region, which is what Einstein’s theory of general relativity predicts, but we do not we haven’t seen yet.”explained Mr. Heino Falcke, working at Radboud University (Netherlands) and chairman of the EHT scientific committee.“This shadow is created by gravitational curvature and capturing light from the event horizon, it reveals a lot about the nature of these interesting objects and allows us to measure their enormous giant masses of the M87 black hole.”
NASA’s Chandra X Observatory captures a close-up of the central region of the M87 galaxy. Photo: NASA
Several calibration and imaging methods revealed a circular structure with a dark central region, the shadow of the black hole, which was confirmed by several independent EHT observations.
“Once we were sure we had captured the shadow, we could compare our observations with computer models, including the physics of warped space, superheated matter, and strong school magnetism.” Many features of the observed images surprisingly match our theoretical knowledge.said Mr. Paul TP Ho, EHT Council Member and Director of the East Asia Observatory, “This gives us confidence in the interpretation of our observations, including our estimate of the black hole mass.”
The first photo of a black hole in history was taken by the EHT project. The photo shows a circle created by light bending in an intense gravity environment around a black hole. This image constitutes the most definitive proof yet of the existence of supermassive black holes and opens a new door in the field of research on black holes, event horizons and gravity. Photo: Collaboration with the Event Horizon telescope
Building the EHT presented a huge challenge, requiring the upgrade and connection of an array of eight existing telescopes, which were deployed in many challenging high-altitude locations around the world. These places include the volcanoes of Hawaii and Mexico, the mountains of Arizona and the Sierra Nevada mountain range, the Atacama Desert in Chile, and even Antarctica.
The EHT observations use a technique called very long baseline interferometry (VLBI) to synchronize telescopes around the world and take advantage of our planet’s rotation to create an Earth-sized telescope, observing at a length 1.3 mm wave. VLBI allows the EHT to achieve an angular resolution of 20 microarcseconds, sufficient to read a New York newspaper from a sidewalk café in Paris.
A simulated image of a black hole. Photo: Hotaka Shiokawa
The telescopes contributing to this result are ALMA, APEX, IRAM 30 Meter Telescope, James Clerk Maxwell Telescope, Alfonso Serrano Large Millimeter Telescope, Near-Millimeter Array, Near-Millimeter Telescope millimeter and the South Pole Telescope. Many petabytes of raw data from these telescopes were combined by specialized supercomputers at the Max Planck Institute for Radio Astronomy and MIT’s Haystack Observatory.
The Atacama Large Millimeter Glass Line (ALMA) contributed greatly to the EHT project. Photo: Wikipedia
The construction of the EHT and the observations announced today represent the culmination of decades of observational, engineering and theoretical work. The success of this global team requires the close collaboration of researchers from around the world. Thirteen partner organizations worked together to create the EHT, using both existing infrastructure and support from various agencies. The bulk of funding comes from the US National Science Foundation (NSF), the EU’s European Research Council (ERC), and East Asian funding agencies.
“We have achieved what was considered impossible just a generation ago” Mr. Doeleman concluded. “Technological advances, connections between the world’s best radio observatories, and innovative algorithms have come together to open a whole new window on the study of black holes and the event horizon.”