After the fall of communism, the truth about that signal was discovered: it came from a colossal radar called Duga, known to NATO as "Steel Yard." After the Chernobyl nuclear disaster on April 26, 1986, the Duga antenna was located within the exclusion zone. Before the Russian invasion of Ukraine, this enormous radar had become a tourist destination for visitors to the exclusion zone, with certain access restrictions. It should be remembered that Russian invaders reached the Chernobyl exclusion zone at the beginning of the war, during their operation to take Kyiv, although they eventually had to withdraw, leaving behind abandoned military equipment. Recently, the YouTube channel Chornobyl Family, managed by Alex, a Ukrainian scientist working in the exclusion zone, published an interesting 4K video showing images of the exterior and interior of this antenna:---