He obtained his Ph.D. in Astrophysics at the University of Oxford in 1950. Between 1959 and 1960 he was Research Associate at the University of California, Lick Observatory, and between 1960 and 1961 held the same position at the University of Chicago, Yerkes Observatory. In 1961 he was an Astronomer at the Vatican Observatory, becoming Director of the Observatory in 1970. He specialised in galactic structure, interferometry, optical instruments, and polarization. From 1949 to 1953 he was editor of The Observatory. In addition to his many scientific publications, he deserves to be remembered for his excellent series of informative articles published in L'Osservatore Romano. He was a member of the Pontifical Academy of Sciences and many other national and international academies.