Reports of unidentified flying objects and alien encounters have sparked amateur research (ufology), government investigations, and popular interest in the subject. Historically, however, scientists have generally greeted the topic with skepticism, most often dismissing ufology as pseudoscience and believers in unidentified flying objects and aliens as irrational or abnormal. Believers, in turn, have expressed doubts about the accuracy of academic science. This study examines the historical sources of the mutual mistrust between ufologists and scientists. It demonstrates that any science doubt surrounding unidentified flying objects and aliens was not primarily due to the ignorance of ufologists about science, but rather a product of the respective research practices of and relations between ufology, the sciences, and government investigative bodies.