In 2002, he co-authored with Alessandro Omizzolo, a priest-astronomer on the staff of the Observatory, "Wayfarers in the Cosmos: The Human Quest for Meaning". He also took on a public role as an expert on the intersection of science and Catholicism. In 1994 he said that he was open to the existence of extraterrestrial life and that Christianity could reconcile its theology with such a discovery. He criticized the Church's lukewarm acceptance of responsibility for its prosecution of Galileo in the early seventeenth century.