asteroids named after three Jesuits and a Pope

These are the names of the four asteroids named after three astronomers from the Vatican Observatory, and Pope Gregory XIII.
Pope Gregory, who was born Ugo Boncompagni, is the Pope to whom we owe the reform of the calendar (later known as the Gregorian Calendar) and the beginning of the tradition of papal astronomers and observatories. The astronomers after whom three celestial bodies have been named are the Jesuits Johann Hagen, who was director of the Vatican Observatory from 1906 to 1930, Bill Stoeger, cosmologist and theologian, and Robert Janusz, currently on the staff of the Vatican Observatory.