This dissertation explores efforts to design and execute scientific studies of unidentified flying objects (UFOs) in the United States in the midst of the Cold War as a means of examining knowledge creation and the construction of scientific authority and credibility around controversial subjects. I begin by placing officially-sanctioned, federally-funded UFO studies in their appropriate context as a Cold War national security project, specifically a project of surveillance and observation, built on traditional arrangements within the military-industrial-academic complex. I then show how non-traditional elements of the investigations – the reliance on non-expert witnesses to report transient phenomena – created space for dissent, both within the scientific establishment and among the broader American public. By placing this dissent within the larger social and political instability of the mid-20th century, this dissertation highlights the deep ties between scientific knowledge production and the social value and valence of professional expertise, as well as the power of experiential expertise in challenging formal, hegemonic institutions.