Up until this May, 2019, Sagittarius A* (Sgr A*), the Milky Way’s central supermasive black hole appeared like a massive, dormant volcano, a sleeping monster, a slumbering region of spacetime where gravity is so strong that “what goes into them does not come out.”
On Feb. 14, 1990, the Voyager 1 spacecraft looked back at our solar system and snapped the first-ever pictures of the planets from its perch at that time beyond Neptune. This past April, the Event Horizon Telescope (EHT) team unveiled humanity’s first image of a supermassive black hole –described as the Gates of Hell and the End of Spacetime– the picture of galaxy Messier 87’s central supermassive black hole. A monster the size of our solar system, and bigger, with the mass of six and a half billion suns, with a ring of gas—in hues of red, orange, and yellow—glowing around it, the shadow cast by the event horizon, predicted by Einstein’s theory of general relativity.
The first direct image of the M87 Galaxy’s supermassive black hole that’s almost the size of our solar system required telescopes of unprecedented precision and sensitivity to give the human species a look into the unknown. The realization of this telescope – the Event Horizon Telescope – was a formidable challenge which required upgrading and connecting a planet-scale network of eight pre-existing telescopes deployed at a variety of challenging high-altitude sites, including volcanoes in Hawaii and Mexico, mountains in Arizona and the Spanish Sierra Nevada, the Chilean Atacama Desert, and Antarctica.
“A medium-sized galaxy fell through the center of M87, and as a consequence of the enormous gravitational tidal forces, its stars are now scattered over a region that is 100 times larger than the original galaxy!” said Ortwin Gerhard, head of the dynamics group at the Max Planck Institute for Extraterrestrial Physics about the monster elliptical galaxy that harbors the now iconic black hole the size of our solar system imaged for the first time ever by the Event Horizon Telescope (EHT) on April 10, 2019.