Publicado 05/05/2016 por Horacio Estigarribia en Guaraníes y Jesuítas

Astronomy in the Jesuit Missions

A poet of science

He built the observatory of San Cosme y San Damián He wrote the first text on astronomy in the region He created his own instruments observing and predicting solar and lunar eclipses

Ignacio Telesca Suárez
Research Professor at the Universidad Católica de Paraguay

With the eclipse at the end of 1994 the legacy of the Jesuit astronomer Buenaventura Suarez reemerged with the help of Father Melia. Today, this legacy is once again being honored with the February 1st inauguration of a street in our city bearing his name, the “Jesuit priest and first astronomer of Paraguay, builder of the San Cosme y San Damián Observatory in the 18th Century,” as expressed in the invitation from the event’s promoter the Asociación de Aficionados a la Astronomía.

On this occasion we explore the life of the first known author of a text on astronomy in this part of the world. We draw mostly from the works of the Argentine mathematician Guillermo Furlong who wrote extensively about the era of Spanish rule (Buenos Aires, 1945) and other scholars such as Hugo Storni.

In Santa Fe de la Vera Cruz

On September 3rd, 1678 Buenaventura Suarez came into this world in Santa Fe de la Vera Cruz which is found along the Parana River. He attended a Jesuit school in his hometown where he enthusiastically studied under the Ratio Studiorum which beyond the four basic disciplines included study of Euclid’s elements, Juan de Sacrobusco’s sphere, and geography according to Glarean. firmaBSuarez He entered the Society of Jesus on April 4th, 1695 in the Jesuit Province of Paraguay (founded February 9th, 1604 which at first included the current territories of Argentina, Paraguay, Uruguay, Chile as well as part of Bolivia and Brazil).

This new province was no stranger to scientific study. In 1617, the Jesuit Pedro Comentali from Naples had already arrived at 21 years old who was widely referred to as “the mathematician.” In both 1639 and 1652, the Superior Generals in Rome lobbied for his inclusion in arithmetic publications on the trajectory of stars and Jupiter’s satellites as well as calling for the creation of a culture more conducive to science. They also authorized him to take three or four books and mathematical instruments.

Furlong speculates that these books may have been those of fellow Italian Tartaglia such as Trattato de numeri e misure (1556 – 1560), Nuova Sciencia (1531), and Trattato de Arithmetic among others.

It is worth noting that Comentali was already in San Ignacio (Paraguay) by 1628 until his death in 1664. As such we surmise that a tradition of astronomy and familiarity of these instruments among the indigenous population already existed allowing them to observe the heavens in another manner.

The Belgian Jesuit- and Comentali’s contemporary-Luis de la Croix arrived in the province in 1640 (born in 1602). Las Cartas Annuas de 1669-1670 which refer to his life and document his passing in Córdoba in 1671, affirm that he studied philosophy and dedicated himself to the mathematical areas of perspective and cosmography. Furthermore, it is noted that he completed a map of all of Peru which earned him high prestige among Europeans as many scholars solicited copies. He also worked in other related areas such as perspectives which were solicited in Belgium for publication.

Without a doubt, at the end of the 17th Century, Buenaventura Suarez found in Córdoba a very significant scientific tradition.

In addition to the names cited above, we also recognize those of the Italian Falconer who las Cartas Annuals de 1653 attributed the study of humanities, philosophy, and above all mathematics; we must also mention the Spanish mathematician and mechanic Juan Montijo and French architect Felipe Lamaire as well as a great number of sculptors and cartographers. From Pedro Diego de Torres’s Paraguay Cum Regionibus (the first in the province) created in 1609, Tucumán el Santa Cruz de la Sierra, to the Paraquariae Provincial Societal de Jesus Cum Acjecentibus Novissima Descriptor created in 1722 by the Jesuit cartographer from Buenos Aires Juan Francisco de Avila (who was born in 1663 and who died in his city of birth in 1733). Together these men created 18 maps of the Province of Paraguay.

These men, the books they brought to the province, and the scientific tradition were sources of learning for Buenaventura Suarez who never left the province to deepen his understanding of mathematics or astronomy.

In San Cosme and San Damián

In the year 1632, the reduction in San Cosme y San Damián was founded. It’s first location was in the mountains of Tape (modern day Brazil); however, it was short-lived because of conflicts with the Paulistas. Six years later it was moved further South and depended upon the mission in Candelaria. Buenaventura Suarez oversaw the move as well as later moves in 1640 near Encarnacion and to its current location in the Department of Itapúa in 1760.

Father Suarez arrived in San Cosme in 1706 when the reduction had nearly 1500 habitants. From his arrival until he published his Lunario in 1739 and 1745, no astronomical instruments came from Europe. He utilized instruments that he himself constructed. From the introduction of his aforementioned book, we find two other biographical details:

After having communicated to the curious the lunary over a period of 33 years, I determined to give light to this lunary over the period of a century… to this end, I have used among others the astronomical tables of Philipo de la Hire, which were finished in Paris in 1702 and are the best of the times; however, my cooptation of the solar and lunar eclipses differ from theirs according to the observations I have made between 1706 and 1739.

I would not have been able to make these observations due to a lack of instruments (these instruments are not brought to these provinces from Europe) without making by hand the necessary instruments for these observations, which are a pendulum clock with first and second minute indexes, astronomical quadrants to reduce, equalize, and adjust the clock to the true hour of the sun, dividing each minute degree by degree, telescope or long range lenses of just two convex glasses of various lengths from 8 to 23 feet.

Using the shorter telescopes of 8 and 10 feet, I observed the solar and lunar eclipses and using the 13, 14, 16, 18, 20, and 23 feet for the appearance and disappearance of Jupiter’s four satellites that I observed over a 13 year period in the town of San Cosme achieving 147 of the most exact observations…I sent these to Father Nicasio Grammatici of the Society of Jesus in Europe who sent me his own observations carried out in the Colegio Imperial de Madrid and in Alberga del Palatinado, the copies and exact observations of Nicolas del Isle from St. Petersburg, those of Father Ignacio Koegler in the court of Peking, as well as those of the doctor Don Pedro Peralta which agreed with mine.

Beyond this long recount, there is little left to add other than that the lenses for his instruments were also made by hand (both scientific and artisanal) and that he also sent his findings on Jupiter’s satellites to Celsius (for who the Celsius thermometer is credited), who shared them with the astronomer Vergartin who said referring to Buenaventura Suarez’s findings “those of the Sun that Buenaventura Suarez observed and recorded in Paraguay, I cite with pleasure not only because they are beautiful and agree with each other magnificently but also because they have not been published” while at the University of Uppsala in Sweden in 1741-1742. Vergartin also preferred his observations’ accuracy to those of astronomers in Paris, London, St. Petersburg, and Peking.

The Lunario de un siglo (1744)

In 1739 he released his work for printing by the title Lunario de un siglo que comienza en enero del año 1740 y acaba en diciembre del año 1841.

“It contains the principal aspects of the Sun and Moon, these being the conjunctions, oppositions, and quarters with the Sun, according to their true movements and predicts the eclipses of both the Sun and the Moon, visible in these Jesuit missions in the Province of Paraguay for the entire century… providing some rules… for the lunaries of the following years from 1842 to 1903.”

Title and Summary of the book

This work was published on five occasions, the first being in 1744 and of which no copies exist and the location of publishing is unknown. It was republished in Lisbon in 1748, in Barcelona in 1752, in Ecuador in 1759, and finally in Corrientes in 1856.

El Lunario de un siglo was not only commended in its era but also in the present, highlighting not just its prediction of eclipses on precise dates but also its inclusion of details such as the beginning, climax, end, and magnitude for a precise location with the theoretical approximation to the minute, something “that cannot be achieved without undergoing very complicated procedures,” as the modern astronomer José Ubach stated.

This entire undertaking, which according to records, the indigenous Guarani assisted in from the observations to the construction of the instruments, was carried out in addition to his other pastoral duties.

He was the superior in San Cosme and there were never more than three Jesuits at the reduction at a time.

In Santa María

In 1745, at the time of the first publishing of the Lunary, the necessary astronomical instruments arrived in the Province of Paraguay (two of Martinon’s clocks from England and two telescopes, one 12 and the other 24 feet long) for the creation of a new-and according to accounts from the era-splendid observatory. The first in this part of the world.

According to Sanchez Labrador, at this time, Father Suarez was in Apostoles; however, he would later return to San Cosme where he built the observatory and continued perfecting his research. Shortly before his 72nd birthday, on August 24, 1750, the first astronomer born in the Province of Paraguay and he who as Ricardo Rojas stated “shuffled his Pythagorean numbers like a poet of science and watched the Pleiades shine for the sacred Indians on the dense waters of the Parana River,” died in the Santa Maria reduction (Argentina).