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  • Writer's pictureMary Allen

British Jesuits and Astronomy

The Jesuits and wider Catholic Church have a long history with astronomy. In October 1582, Pope Gregory XIII introduced the new Gregorian calendar to replace the Julian system which, by that time, had drifted by ten days. The new calendar also altered the lunar cycle used by the Church to calculate the date for Easter, restoring it to the time of the year as originally celebrated by the early Church. The Gregorian calendar was developed by the astronomer Aloysius Lilius and modified by the German Jesuit Christopher Clavius at the Collegio Romano using astronomical data. It was for this purpose that the precursor to the Vatican Observatory, the Gregorian Tower, was completed in 1580.

From the mid-nineteenth century, research and observation work in meteorology has been carried out in Jesuit observatories across the world, and in many countries, Jesuits established the first meteorological stations. The observatory at Stonyhurst was established in 1838, and intended to serve as a meteorological station. With the foundation of the Meteorological Office in 1854, it became one of seven key UK stations, and was managed and operated by the Jesuit priests who ran the school. Fr Stephen Perry SJ (1833-1889) became its director in 1869. Although he wrote several papers on meteorological problems, he was primarily interested in astronomy and made many valuable contributions to the field of solar physics. During the 1870s and 1880s, his work in this discipline took him across the world, leading expeditions to observe eclipses in the West Indies and Russia, to Cadiz to observe the sun’s corona, and led government expeditions to measure Venus’ transit across the face of the sun at Kerguelen Island and Madagascar. The former, which borders Antarctica and is 3,000 miles from any habitation, was referred to by Captain Cook as “the most desolate and barren place on the face of the earth”. From the latter, The Stonyhurst Magazine (March 1883) records that he “brought back with him, amongst other curiosities, a lemur, whose tricks and escapades are the source of great amusement.” At Stonyhurst, in addition to his duties as Director of the observatory, he taught physics and mathematics for almost a quarter of a century, encouraging older pupils to take part in his observations, and set up two telescopes in the grounds for use by the boys. Fr Perry died in December 1889 while leading a Royal Astronomical Society (RAS) expedition to observe a total solar eclipse in the Salut Islands off French Guiana.

Notes about the Stonyhurst Observatory appear often in the ‘Province News’ sections of Letters and Notices, including reports of lectures given by Fr Aloysius Cortie SJ (1859-1925), of drawings of sun-spots and magnetic curves loaned by Stonyhurst to the Royal Society for the Empire Exhibition in 1924, of Jesuits attending meetings of the International Astronomical Union, and of elections of various individuals to societies in the field.

Fr Alfred Weld SJ (1823-1890) was Director of the Stonyhurst Observatory from 1856 to 1860 and Fellow of the RAS. Under his leadership, it was recognised as a meteorological station and admitted to the Kew Observatory Committee. Fr Walter Sidgreaves SJ (1837-1919) was Director between 1863 and 1868 and resumed that post at the death of Fr Perry in 1889. He was greatly respected in scientific circles and was a pioneer in the science of terrestrial magnetism. He accompanied Fr Perry on several of his expeditions and on his resumption of the Directorship devoted himself to stellar spectroscopy, for which he devised instruments to take photographs of stellar spectra. Fr Sidgreaves was elected a Fellow of the RAS in 1891, and served for many years on its council. He continued his routine duties at the observatory up to a month before his death.

Fr Cortie maintained the work of his predecessors, Frs Perry and Sidgreaves, in the field of astrophysics and was especially interested in the relationship between sun-spots and terrestrial magnetism. He took part in several eclipse expeditions and brought back photographs of the sun’s corona and spectrum. He contributed papers to the RAS, on whose council he sat for many years, and was also Director of the Solar Section of the British Astronomical Association. From 1919 he was assisted by Fr James Rowland SJ (1875-1948), who took over as Director in 1932. Rowland became known throughout Lancashire for his weather forecasts published in the Lancashire Daily Post. He was a member of the RAS, the Royal Meteorological Society, and the General Committee of the British Association for the Advancement of Science. Fr Rowland was also interested in seismology and among his notable successes was the location of the epicentre of the North Sea earthquake in 1931 and his work on the Wensleydale earthquake of 1933. During his directorship, Fr Rowland shifted the focus of the Observatory away from strictly astronomical work to take in his meteorological and seismological interests, though he continued the daily solar drawings to within a few years of his death, and in 1933 he used the Observatory to determine the time the planet Saturn takes to rotate on its axis. Fr Rowland completed the 100th year of continuous recordings at the Observatory and with the suspension of its public work in 1947, his health failing, he retired.

To return to the Vatican Observatory, a reflection on Jesuits and astronomy could not omit Fr Patrick Treanor SJ (1914-1978), who was its Director between 1970 and 1978. According to his obituary, by the time Fr Treanor had entered Theology in 1949, “he had already established his reputation as one of the most promising of the younger generation of astronomers in this country.” By this time, he was a member of the council of the RAS and co-editor of its journal The Observatory. He

spent two years carrying our research at the observatories of Lick and Yerkes in the US and then went to the Vatican Observatory in 1961. Nine years later, he was appointed Director and remained in that post until his death. During his time there, he was commissioned to design a large sundial for an extension to the Vatican Palace galleries in Rome. The Jesuit community at Castle Gandolfo lives in the Pontifical Palace, and the principal telescopes are in the Papal Gardens, so it is likely that the Pope would have had contact with the astronomers. In fact, when Pope Paul VI gave an audience after Fr Treanor’s funeral, he told the attendees of his own “high regard for him as a man and a priest, as well as an astronomer.”

30 June is Asteroid Day, an annual global event designated by the United Nations, which prompted this recollection of the British Jesuit association with astronomy. The personal papers of Fr Treanor have recently been catalogued and are available to consult at the Archives. Please contact us if you would like to know more about the individuals mentioned in the post or for more information about the archives.


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