The Horizon Telescope (EHT) event ̵
This breakthrough was announced today in a series of six articles published in a special edition of Astrophysical Magazine Letters. The picture shows the black hole in the center of Messier 87, a massive galaxy in the nearby Virgo galaxy cluster. This black hole is 55 million light-years from Earth and has a mass 6.5 billion times the size of the Sun.
The EHT connects telescopes around the world to form an unprecedented virtual earth-sized telescope. The EHT offers scientists a new way to study the most extreme objects in the universe predicted by Einstein's general theory of relativity during the Centennial Anniversary of the historical experiment that first confirmed the theory.
"We took the first picture of a black hole," said Sheperd S. Doeleman, director of the Center for Astrophysics EHT project Harvard & Smithsonian. "This is an extraordinary scientific achievement made by a team of more than 200 researchers."
Black holes are extraordinary cosmic objects with enormous masses but extremely compact sizes. The presence of these objects has an extreme impact on their environment, distorts space-time, and overheats any surrounding material.
"When you dip into a bright area like a disk of glowing gas, we expect a black hole to create a dark area similar to a shadow – something predicted by Einstein's general theory of relativity, as we still do Never saw before, "said EHT Science Council Chairman Heino Falcke from the Radboud University in the Netherlands. "This shadow, caused by the bending of gravity and the capture of light through the event horizon, reveals much about the nature of these fascinating objects and has enabled us to measure the enormous mass of the M87 black hole."
Several calibration and imaging methods have shown an annular structure with a dark central area – the shadow of the black hole – that has passed several independent EHT observations.
"Once we were sure that we had shadowed, we could compare our observations to extensive computer models involving the physics of distorted space, overheated matter, and strong magnetic fields. Many of the features of the observed image are surprisingly consistent with our theoretical understanding, "says Paul T.P. Ho, EHT board member and director of the East Asian Observatory. "This makes us confident in the interpretation of our observations, including our assessment of the mass of the black hole."
"The confrontation of theory with observations is always a dramatic moment for a theorist. It was a relief and a pride to see that the observations matched our predictions so well, "said Luciano Rezzolla, board member of EHT, Goethe University.
The creation of the EHT was an enormous challenge, requiring the development and connection of a worldwide network of eight existing telescopes deployed at various demanding high altitude locations. These places included volcanoes in Hawaii and Mexico, mountains in Arizona and the Spanish Sierra Nevada, the Chilean Atacama Desert and the Antarctic.
The EHT observations use a technique called very long baseline interferometry (VLBI) and the telescope synchronizes facilities around the world and use the rotation of our planet to form a huge, Earth-sized telescope a wavelength of 1.3 mm observed. With VLBI, the EHT can achieve an angular resolution of 20 microseconds – enough to read a newspaper in New York at a Parisian café.
The telescopes contributing to this result were ALMA APEX, the 30 meter long IRAM telescope, the James Clerk Maxwell Telescope, the large millimeter Telescope Alfonso Serrano, the submillimeter array, the submillimeter telescope and the South Pole telescope. Petabytes of raw data from the telescopes were combined by highly specialized supercomputers hosted by the Max Planck Institute for Radio Astronomy and the MIT Haystack Observatory.
European institutions and financial resources have played a crucial role in these global efforts, including the participation of advanced European telescopes and the support of the European Research Council, notably a € 14 million grant to the BlackHoleCam project. Support from ESO, IRAM and the Max Planck Society was also key. "This result builds on decades of European expertise in millimeter astronomy," commented Karl Schuster, director of IRAM and member of the EHT board.
The Event Horizon Telescope (EHT) – an assembly of eight space-based radio telescopes forged on an international scale – was designed to capture images of a black hole. At coordinated press conferences around the world, the EHT researchers showed that they were able to reveal the first direct visual evidence of a supermassive black hole and its shadow. This 17-minute film examines the efforts that have led to this historic image, from the science of Einstein and Schwarzschild to the struggles and successes of EHT collaboration. Credit: ESO
The construction of the EHT and the observations announced today form the culmination of decades of observational, technical and theoretical work. This example of global teamwork required close collaboration from researchers around the world. Thirteen partner institutions worked together to create the EHT, using both the existing infrastructure and the support of various agencies. Key financing has been provided by the US National Science Foundation (NSF), the European Research Council of the European Union (ERC) and funding agencies in East Asia.
The Event Horizon Telescope (EHT) – a planetary-scale arrangement of eight ground-based radio telescopes forged through international collaboration – was developed to capture images of a black hole. At coordinated press conferences around the world, EHT researchers showed that they were able to reveal the first direct visual evidence of a supermassive black hole and its shadow.
"ESO is pleased to have made a significant contribution to European leadership with leadership and key role in two of the Chile-based EHT component telescopes – ALMA and APEX," commented Xavier Barcons, Director General of ESO. "ALMA is the most sensitive device in the EHT, and its 66 high-precision antennas have been critical to the success of the EHT."
Expecting the first image of In A Black Hole, Jordy Davelaar and her colleagues built a virtual reality of one of these fascinating astrophysical objects. Your simulation shows a black hole surrounded by luminescent material. This matter disappears in a swirl-like manner in the black hole and becomes a glowing plasma due to the extreme conditions. The emitted light is then deflected and deformed by the strong gravity of the black hole.
"We have achieved something that was considered impossible a generation ago," concluded Doeleman. "Breakthroughs in technology, connections between the world's best radio observatories and innovative algorithms led to a whole new window on black holes and the event horizon."
This shows the artistic impression the black hole in the heart of the giant elliptical galaxy M87. This black hole was selected by the Event Horizon Telescope as an object for paradigm-shifting observations. The overheated material surrounding the black hole is shown.
The impression of this artist shows the black hole in the heart of the huge elliptical galaxy M87. This black hole was selected by the Event Horizon Telescope as an object for paradigm-shifting observations. The superheated material that surrounds the black hole is shown as well as the relativistic jet that is launched from the M87 black hole.