This ethnographic account of the rituals of risk and error after NASA's Columbia accident reveals the mechanisms by which sociological theory traveled across the disciplinary boundary to public and policy domains. The analysis shows that analogy was the instigator of it all, enabled by the social mechanisms of professional legitimacy, conversation, technologies, time, networks, and social support. It demonstrates the work sociologists do when theory travels from professional sociology to nonacademic audiences and what happens to the theory and the sociologist in the process. It reveals the tensions when professional sociology, critical sociology, public sociology, and policy sociology are joined. A study of sociology in the field, it shows how sociologists negotiate the meaning of their work in a nonacademic situation. Thus, this account contributes to research and theory on social boundaries, the diffusion of ideas, the sociology of scientific knowledge, and current debates about public sociology and the role of the sociologist, adding to the sociology of our own work. At 9:00 a.m. EST on February 1, 2003, NASA's space shuttle Columbia disintegrated as it was streaking across the sky over Texas toward the landing site at Kennedy Space Center, Florida. Immediately, NASA declared a "shuttle contingency," executing the contingency action plan that the space agency had established after the Challenger accident 17 years before. As part of that plan, NASA activated the Columbia Accident Investigation Board (CAIB) to identify the causes of this second shuttle disaster. The technical failure, the CAIB concluded, was initiated 81.7