People stand at the bottom of the disused Soviet-build over-the-horizon radar (OTH) system "Duga-1" near Chernobyl during a visit on April 24, 2021. - The 35th anniversary of the world's worst nuclear disaster will be commemorated in the ex-Soviet country on April 26, 2021. (Photo by Genya SAVILOV / AFP)

People stand at the bottom of the disused Soviet-build over-the-horizon radar (OTH) system "Duga-1" near Chernobyl during a visit on April 24, 2021. - The 35th anniversary of the world's worst nuclear disaster will be commemorated in the ex-Soviet country on April 26, 2021. (Photo by Genya SAVILOV / AFP)

A woman takes pictures at the bottom of the disused Soviet-build over-the-horizon radar (OTH) system "Duga-1" near Chernobyl during a visit on April 24, 2021. - The 35th anniversary of the world's worst nuclear disaster will be commemorated in the ex-Soviet country on April 26, 2021. (Photo by Genya SAVILOV / AFP)

People take pictures at the bottom of the disused Soviet-build over-the-horizon radar (OTH) system "Duga-1" near Chernobyl during a visit on April 24, 2021. - The 35th anniversary of the world's worst nuclear disaster will be commemorated in the ex-Soviet country on April 26, 2021. (Photo by Genya SAVILOV / AFP)

A man takes pictures at the bottom of the disused Soviet-build over-the-horizon radar (OTH) system "Duga-1" near Chernobyl during a visit on April 24, 2021. - The 35th anniversary of the world's worst nuclear disaster will be commemorated in the ex-Soviet country on April 26, 2021. (Photo by Genya SAVILOV / AFP)

The Duga-1 array, an over-the-horizon (OTH) radar system used as part of the Soviet ABM early-warning network, near Chernobyl. Chernobyl in November 2015. The Chernobyl disaster (also referred to as the Chernobyl accident or simply Chernobyl) was a catastrophic nuclear accident that occurred on 26 April 1986 at the Chernobyl Nuclear Power Plant in the town of Pripyat, in Ukraine (then officially the Ukrainian SSR), which was under the direct jurisdiction of the central authorities of the Soviet Union. An explosion and fire released large quantities of radioactive particles into the atmosphere, which spread over much of the western USSR and Europe. The Chernobyl disaster was the worst nuclear power plant accident in history in terms of cost and casualties. Photo by Francois Pauletto/ABACAPRESS.COM

The Duga-1 array, an over-the-horizon (OTH) radar system used as part of the Soviet ABM early-warning network, near Chernobyl. Chernobyl in November 2015. The Chernobyl disaster (also referred to as the Chernobyl accident or simply Chernobyl) was a catastrophic nuclear accident that occurred on 26 April 1986 at the Chernobyl Nuclear Power Plant in the town of Pripyat, in Ukraine (then officially the Ukrainian SSR), which was under the direct jurisdiction of the central authorities of the Soviet Union. An explosion and fire released large quantities of radioactive particles into the atmosphere, which spread over much of the western USSR and Europe. The Chernobyl disaster was the worst nuclear power plant accident in history in terms of cost and casualties. Photo by Francois Pauletto/ABACAPRESS.COM

The Duga-1 array, an over-the-horizon (OTH) radar system used as part of the Soviet ABM early-warning network, near Chernobyl. Chernobyl in November 2015. The Chernobyl disaster (also referred to as the Chernobyl accident or simply Chernobyl) was a catastrophic nuclear accident that occurred on 26 April 1986 at the Chernobyl Nuclear Power Plant in the town of Pripyat, in Ukraine (then officially the Ukrainian SSR), which was under the direct jurisdiction of the central authorities of the Soviet Union. An explosion and fire released large quantities of radioactive particles into the atmosphere, which spread over much of the western USSR and Europe. The Chernobyl disaster was the worst nuclear power plant accident in history in terms of cost and casualties. Photo by Francois Pauletto/ABACAPRESS.COM

The Duga-1 array, an over-the-horizon (OTH) radar system used as part of the Soviet ABM early-warning network, near Chernobyl. Chernobyl in November 2015. The Chernobyl disaster (also referred to as the Chernobyl accident or simply Chernobyl) was a catastrophic nuclear accident that occurred on 26 April 1986 at the Chernobyl Nuclear Power Plant in the town of Pripyat, in Ukraine (then officially the Ukrainian SSR), which was under the direct jurisdiction of the central authorities of the Soviet Union. An explosion and fire released large quantities of radioactive particles into the atmosphere, which spread over much of the western USSR and Europe. The Chernobyl disaster was the worst nuclear power plant accident in history in terms of cost and casualties. Photo by Francois Pauletto/ABACAPRESS.COM