| HERCULEAN MISSION WITH LUCK Creating the virtual telescope EHT was a formidable challenge which required upgrading and connecting a worldwide network of radio 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. France Cordova, director of the U.S. National Science Foundation, described the mission as "a herculean task" that will imprint on people's memory at the press conference. Black holes are so far away from us, and the biggest of them like M87 is "about the size of an orange on the Moon," Harvard astrophysical professor Andrew Strominger told Xinhua. "It was only through the ingenious efforts of the event horizon telescope collaboration that we were able to obtain." The EHT observations use a technique called very-long-baseline interferometry (VLBI) that can synchronise telescope facilities around the world and exploit the rotation of our planet to form one huge, Earth-size telescope, enough to read a newspaper in New York from a sidewalk cafe in Paris. Then, during two years afterwards, the researchers used a supercomputer called correlator and refined algorithms to merge the light, said Dan Marrone, EHT co-investigator and an associate professor of Astronomy at the University of Arizona. Despite the sharpened tool and hard work, Doeleman still called the image-taking kind of a "coincidence." The radio waves go through the hot gas, traveled 60,000 years through M87 and another 55 million years through intergalactic space into the Milky Way, and then they come to the Earth with obstructive water vapor in its atmosphere, explained Doeleman. "Nature was very kind to us," he said. | 
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