The dissertation examines knowledge production practices following the 1986 Chernobyl nuclear accident and describes the production of invisibility of its consequences: practices that displace radiation and its health effects as an object of public attention and scientific research, and make them unobservable. As a result, links between radiation exposures and their health effects are not constructed, and 'Chernobyl consequences' dissolve into individual health problems of unspecific origins. Processes of the production of in/visibility are analyzed using the example of Belarus, one of the former Soviet Union republics, which was covered with seventy percent of the Chernobyl fallout. The analysis is based on extensive archival and ethnographic research, including analysis of twenty years of media coverage, and national and international scientific publications, field trips into the most contaminated areas, and interviews with experts, government authorities, and members of the affected populations. Building on the analytical traditions in communication studies and science and technology studies, the dissertation contributes to research into systematic production of scientific uncertainty and non-knowledge