Jacques Vallee holds a master's degree in astrophysics from France and a PhD in computer science from Northwestern University. He is the author of several books about high technology and unidentified phenomena, a subject that first attracted his attention as an astronomer in Paris. While analyzing observations from many parts of the world, Vallee became intrigued by the similarities in every culture in patterns between modern sightings and historical reports of encounters with flying objects and their occupants. After a career as an information scientist with Stanford Research Institute and the Institute for the Future, where he served as a principal investigator for the groupware project on the ARPANET, the prototype of the Internet, Vallee cofounded a venture capital firm in Silicon Valley. He lives in San Francisco.

Chris Aubeck was born in London. He moved to Spain at age 19, and after teaching in Cáceres and Madrid for 24 years, he now lives in Granada. His interest in the historical and sociological aspects of unexplained aerial phenomena began at an early age. A student of language and folklore, he has helped compile the largest collection of pre-1947 UFO cases in the world. He has spoken on his research in many articles and on public radio. In 2008 he was awarded a prize for his contributions to the field by the Spanish organization Fundación Anomalía.