This book was designed to answer questions about the origins of NASA-associated names. The impetus for its preparation came from the Johnson Space Center Historian, James M. Grimwood, who called attention to the need for such a compilation. If, besides answering specific questions, the book raises further questions or stimulates the reader to delve further into the subject of space exploration, it will have served its purpose well. Names given to spaceflight projects and programs have originated from no single source or method. Some have their foundations in mythology and astrology, some in legend and folklore. Some have historic connotations. Some are based on a straightforward description of their mission, often resulting in acronyms. (As Webster puts it, an acronym is a "word formed from the initial letters or syllables of the successive parts of a compound term"; hence, "TIROS" for "Television and Infra-Red Observation Satellite.") Some grew out of a formal process within NASA under the NASA Project Designation Committee. Others evolved somewhat casually and were officially adopted after their use had become widespread. Many others, of course, were originated by non-NASA sources when ongoing projects were transferred to NASA from other agencies. Parts I through V list names of launch vehicles, spacecraft, manned spaceflight programs, and sounding rockets. Some of these were the primary responsibility of NASA. Some names apply to projects for which NASA shared responsibility or had a major support role--for instance, the international Alouette satellites. Some names apply to hardware that NASA purchased from another agency, such as the Air Force Agena launch vehicle stage. Part VI lists NASA field installations and gives the origins of their names. This study is limited to names of approved projects through 1974; it does not include names of numerous projects which have been or are being studied or projects that were canceled or postponed before reaching actual flight--such as the Nova large launch vehicle. It does not attempt to record the history of the listed projects except as it may be related to the naming process, nor does it attempt to describe the projects and hardware beyond a nontechnical statement of mission or function. It does, however, present the origins of each name, answering as far as possible who or what organization devised the name, when they adopted it, and what the reasoning was for its selection. The information about each name is as specific as the available documentation could provide.