Right Off the Shelf

Chicago's Adler Planetarium is home to a host of books penned by some influential Jesuit astronomers of years ago

I have always been something of a bibliophile, but in my youth I could hardly anticipate that I would eventually spend a decade working closely with one of the world’s greatest collections of antique astronomy books. As many collectors and researchers know, old books often become old friends when one spends significant amounts of time with them. The rich library at Chicago’s Adler Planetarium & Astronomy Museum has provided me hours of engaging research as well as the sheer thrill of turning the pages of books from centuries ago. “My” collection contains an enormous range of rare books on astronomy and related sciences, from earth-shattering new theories to mundane technical guidebooks to bizarrely enigmatic tomes.

A large subset of volumes by Jesuit authors inhabit the shelves. Why might this be? Seventeenth- and eighteenth-century Jesuit scientists investigated the world around them incessantly. Often polymaths, they excelled in a variety of fields including astron-omy, physics, mathematics, geography, natural history, and what would become ethnography.

Of all the scientific fields in which they sought knowledge, astronomy allowed them perhaps their greatest achievements. These talented men published profusely and corresponded widely with colleagues around Europe, Jesuit and non-Jesuit alike. Some carried their teachings and the work of fellow Jesuits to foreign lands, impacting local astronomies.

Detail from a start map All images courtesy of the Adler Planetarium & Astronomy Museum, Chicago. Visit Adler’s History of Astronomy Department at www.adlerplanetarium.org/history

Company’s web site contains stories about astronomy, from Jesuits working at the Vatican Observatory to Jesuit astronomers Christopher Clavius and Athanasius Kircher, and more. Go to www.companymagazine.org and type “astronomy” in the search engine.

For information about the Vatican Observatory, visit clavius.as.arizona.edu/vo

Jesuit astronomers left an enormous legacy to the history of astronomy in copious volumes that have always intrigued me. These rare books have been collected in libraries around the globe; specialist collections, such as that at the Adler, offer a wide range of artifacts through which the extensive Jesuit contributions to astronomy can be investigated. In the following pages I pull five books that I have always admired from the shelves at Adler. They highlight the accomplishments of Jesuit scientists from luminaries to more-obscure figures. I am drawn particularly to the profuse illustrations in these books—sometimes lavish, other times curious. Through these alluring images we can learn much about the history of Jesuit astronomy.

On his travels in India and China between 1684 and 1708, the Czech Jesuit astronomer Noël (1651–1729) had many opportunities to view the night sky. Interested not only in astronomy but also in literature, Noël published a book of poems and edited a collection of Latin translations of Chinese literature and a collection of letters about the sea (Epistolae marianae).

Upon his return to Prague in 1710, he published his observations and included a large star map showing the south-ernmost constellations. These constellations are not visible from typical European latitudes, and scientists only rarely had chances to travel far enough south to see them. My own travels south of the equator have also revealed this significantly different-looking sky from that visible in the north. Astronomers on board a Dutch expedition to South America in 1595 assembled the stars from this previously invisible part of the sky into constellations based on local South American fauna; they populate the center region of Noël’s chart as does the constellation Indus, represented by a Native American. This handsome map (above) also clearly shows the Southern Cross on the left side.

The Swiss Jesuit astronomer Cysat (1587–1657) studied with Christopher Scheiner, SJ, (see below) and assisted him with his sunspot project. He appears to have published only one book, Mathematica astronomica de loco, motu, magnitudine, et causis cometæ . . . (1619), about the comet of 1618. I have always been particularly fond of comet books, and this is one of our most interesting, even if not as spectacularly illustrated as some others. (This volume also holds an unusual place in book history—and my heart—because a woman, Elizabeth Angermar, printed it; in the early modern period, guild rules occasionally allowed widows and daughters to take over their husbands’ or fathers’ businesses.)

Cysat trained the newly developed telescope on comets and saw enough detail to be the first to describe cometary nuclei. This illustration depicts four different views of the nucleus of the comet of 1618. As the days passed, the nucleus progressed from a solid shape to one filled with starry particles. Despite publishing this sole work, Cysat enjoyed something of a reputation among comet observers of his time, and his drawings of cometary nuclei have been included on the maps of others.

From the 1580s, Jesuit scholars traveled as missionaries to China. Starting with such intrepid voyagers as Matteo Ricci, a long period of scholarly exchange began between Western and Eastern cultures. Jesuit missionaries such as Johann Adam Schall von Bell and Ferdinand Verbiest paid quite a bit of attention to astronomy. Intent on spreading Western scientific knowledge as well as religion, they introduced the Chinese to the newly invented telescope yet protected them from the controversial Copernican theory.

That Jesuits succeeded in promoting an Earth-centered view of the cosmos to Chinese society—a view that persisted for centuries—can be seen in this 1802 book, Hyotenzi Zukai-Zen, “Explanation of Maps of the Regulated Celestial Globe.” It contains a slightly modified illustration of Jesuit Giambattista Riccioli’s conception of our planetary system (see below). This system places Mars in orbit around the Earth with only Mercury and Venus circling the Sun; Riccioli had all three of these planets rotating around the Sun. It is unclear to me as to why Mars is displaced from a typical Riccioli planetary system—it may be an unintentional mistake or the product of a reworking of Riccioli’s theory. Later in the book, a telescope and telescopically viewed images of planets, the Sun, and the Moon reflect the subsequent adoption of this technology into Chinese astronomical practice.

I find this book to be a fascinating combination of Western astronomical concepts with traditional Chinese views of the heavens that attests to a cultural exchange rather than just an imposition of one culture upon another. While Chinese and other Asian astronomers adopted European astronomical theories and observational techniques, they retained their ancient star groupings—another part of the book depicts a star chart with traditional Chinese constellations and 28 lunar mansions that divided the sky.

Scheiner (1575–1650), a Jesuit astronomer, physicist, and mathematician from Germany, discovered sunspots, dark spots on the surface of the Sun caused by areas of strong magnetic fields creating temperature differences. Galileo also discovered sunspots independently, and the two engaged in spirited debate about sunspots and planetary system theories. Scheiner’s best known work, Rosa ursina sive sol (1629) contains numerous maps of the face of the Sun that illustrate his observations of sunspots. While most people today know that one should not look directly at the sun, so also did Scheiner. He did not go blind staring at the Sun to map it but rather used an indirect process of viewing called a camera obscura, a device that projects an image of the Sun through a tube onto a flat surface (usually covered with a sheet of paper for drawing upon).

Sunspot maps such as Scheiner’s converge with one of my personal research interests—that of maps that track time against space. This particular map (above) shows the progression of eight different sunspots over the course of a week, showing how the shapes changed from day to day. Scheiner’s sunspot depictions influenced other solar astronomers, including Poland’s Johannes Hevelius, who produced numerous similar maps.

In the map, two figures hold up the Sun: a putto holding the emblem of the Society of Jesus on bottom left and a bear personifying the Duke of Orsini on bottom right. The latter helps to explain the unusual title for the book, which translates as “The Ursine Rose.” The Orsini family name when Latinized becomes Ursinus, similar to the Latin word ursa or bear; the family coat of arms, grasped by the bear in the map, contains a rose in its upper half. Securing financial support for the costs of producing lavish books such as the Rosa ursina constituted an essential task for all scholars. In thanks for such monetary contributions to their work, the authors often ensured that their patrons would be memorialized in perpetuity in the pages of their books.

Riccioli (1598–1671), a professor at the Jesuit college in Bologna, believed strongly in an Earth-centered scheme of the universe, as did other Jesuits of the time. However, they appreciated certain aspects of the Sun-centered Copernican system. To strike a compromise between the two, they looked to the work of the Danish astronomer Tycho Brahe, whose compromise planetary system kept the Earth at the center of the universe. The Tychonic system set all the planets in motion around the Sun, while the Sun and Moon orbited a central, stationary Earth. In a modification to this hybrid system, Riccioli theorized that the three other inner planets (Mercury, Venus, and Mars) rotated around the Sun while the outer planets (Jupiter and Saturn) encircled the Earth.

When Riccioli published his planetary system in Almagestum Novum (1651), he intentionally referenced the now-outdated Ptolemaic Almagest in the title. One of my favorite allegorical frontispieces begins Riccioli’s “New Almagest”; it is a masterful exposition of the contents of his book. A central scale balances the Copernican system with Riccioli’s own, which weighs more, therefore proving to be the favored concept. A curious figure holds the scale; at first glance she appears to be Urania, the muse of Astronomy, in starry robes and a zodiacal belt, but Riccioli reveals in the preface that she is in fact Astraea or Dike, the goddess of justice. Prominent in the frontispiece is the hundred-eyed Argus, who holds a telescope to his knee, observing the sky through one of his numerous eyes.

Many smaller details yield additional layers of meaning. Underneath the scale lies Ptolemy and his outmoded system with the planets, Sun, and Moon arrayed in concentric circles around a central Earth. At the top, putti hold the individual elements of Riccioli’s system: on the left, the heavenly bodies that circle the Sun (Mercury, Venus, and Mars), and on the right, those that orbit the Earth (the Moon, Saturn, Jupiter with its four Galilean moons, and a comet). These small depictions clearly emphasize new telescopic observations: Jupiter’s four Galilean moons and surface striations, the “handles” of Saturn (only later determined to be a ring),the craters of the Moon, phases of Venus and Mercury, and a spotted nucleus of a comet.

Riccioli’s interests encompassed more than planetary systems. His map of the Moon (produced in conjunction with fellow Jesuit astronomer Francesco Grimaldi), also contained in the Almagestum Novum, became the standard for the time. We use much of his nomenclature to describe lunar craters and other features today. Thus he succeeded in immortalizing 35 Jesuit astronomers by naming lunar craters after them, including Clavius, Cysat (see above), Kircher, Ricci, Scheiner (see above), and Riccioli and Grimaldi themselves.