No. 111/2020

27 HUMBOLDT KOSMOS 111/2020 nae had to have a solid organisational footing. Zensus: “In two years, we had about 50 meetings.” His task as chair- man was to elaborate a detailed agreement balancing out the various interests to serve the common objective. Zen- sus: “That sometimes meant taking the lead.” Now, everyone can picture what a black hole looks like. The one caught by the EHT researchers is in the Virgo Constellation, right in the middle of the enormous elliptical galaxy M87. In the club of black holes it is a particularly massive member, weighing in at 6.5 billion solar masses. The image shows a central area which is actually black. The actual hole is invisible to the eye, hid- den in this dark zone and surrounded by a bright region. Zensus explains: “That is hot, radiating matter that has collected in a ring around the hole.” A considerable part of the shining matter was even behind the black hole. This is because such a massive object bends space and time so strongly that it deflects light. After a certain point, the beams of light then run circles around the object. So, to be precise, the image does not show the black hole itself, but its shadow and the immediate en­ vironment. COOPERATION ACROSS NATIONAL BORDERS One of the reasons why black holes are so popular is because they have a mystical, threatening aura. The ficti- tious example in the film Interstellar is called Gargantua, like the father of all grotesque giants in the eponymous Renaissance story by Rabelais. Today, its genuine equiva- lent in galaxy M87 has also sparked the interest of people who are otherwise indifferent to physics and astronomy. “We are now perceived quite differently,” says Zensus. “I never used to be invited to give lectures to SMEs; now I am.” And young people are showing much more interest, too, which means a boost for scientific and technical sub- jects. Zensus: “Neither of my sons works in science. Now their friends ask them about the fascinating research their father and his colleagues are doing. That’s a new experi- ence for me.” › ANTON ZENSUS with design engineer, Gino Tuccari, at a data recorder in the Bonn laboratory for Very Long Baseline Interferometry (VLBI). Photo (left): SPIEGEL-Verlag Rudolf Augstein GmbH & Co. KG