to astronomy than theology. Eventually his superiors in the Jesuit order officially assigned him to the task of astronomical research. However, he also continued to write on theology (see below). Riccioli built an astronomical observatory in Bologna at the College of St. Lucia, equipped with many instruments for astronomical observations, including telescopes, quadrants, sextants, and other traditional instruments. Riccioli dealt not only with astronomy in his research, but also with physics, arithmetic, geometry, optics, gnomonics, geography, and chronology. He collaborated with others in his work, including other Jesuits, most notably Francesco Maria Grimaldi (1618–1663) at Bologna, and he kept up a voluminous correspondence with others who shared his interests, including Hevelius, Huygens, Cassini, and Kircher. He was awarded a prize by Louis XIV in recognition of his activities and their relevance to contemporary culture. Riccioli continued to publish on both astronomy and theology up to his death. He died in Bologna at 73 years of age. Scientific work Almagestum Novum One of Riccioli's most significant works was his 1651 Almagestum Novum (New Almagest), an encyclopedic work consisting of over 1500 folio pages (38 cm x 25 cm) densely packed with text, tables, and illustrations. It became a standard technical reference book for astronomers all over Europe: John Flamsteed (1646–1719), the first English astronomer royal, a Copernican and a Protestant, used it for his Gresham lectures; Jérôme Lalande (1732–1807) of the Paris Observatory cited it extensively even though it was an old book at that point; the 1912 Catholic Encyclopedia calls it the most important literary work of the Jesuits during the seventeenth century. Within its two volumes were ten "books" covering every subject within astronomy and related to astronomy at the time: the celestial sphere and subjects such as celestial motions, the equator, ecliptic, zodiac, etc. the Earth and its size, gravity and pendulum motion, etc. the Sun, its size and distance, its motion, observations involving it, etc. the Moon, its phases, its size and distance, etc. (detailed maps of the Moon as seen through a telescope were included) lunar and solar eclipses the fixed stars the planets and their motions, etc. (representations of each as seen with a telescope were included); comets and novae ("new stars") the structure of the universe—the heliocentric and geocentric theories, etc. calculations related to astronomy. Riccioli envisioned that the New Almagest would have three volumes, but only the first (with its 1500 pages split