Agustín Udías, born in Santander, Spain, is a Jesuit and Professor Emeritus of Geophysics at Universidad Complutense de Madrid. He has conducted research and held teaching posts at the University of California, Berkeley, at the Wolfgang Goethe Universität, Frankfurt am Main and at the Universidad de Barcelona. Among his books, Principles of Seismology (Cambridge University Press, 1999, 2018), Searching the Heavens and the Earth: The History of Jesuit Observatories (Kluwer, 2003) and Jesuit Contribution to Science. A History (Springer, 2015). He has published scientific articles on the topics of earthquake source mechanism, seismicity and seismotectonics of the Mediterranean region and about the relationship between science and religion and the history of Jesuit scientists.