ROME – 2009 is officially “The Year of Astronomy,” commemorating Galilei’s first observation of the Moon through his telescope in November of 1609. Born in Pisa, Galileo Galilei worked in Florence, where the fourth centennial of his discovery is being celebrated with a stunning and sophisticated exhibition which took four years to prepare. Galileo, Images of the Universe from Antiquity to the Telescope illustrates the unity of the two cultures, science and art, for millennia. It also shows how astrology acquired a theological cast before evolving into astronomy, even as it bequeathed us the daily newspaper’s horoscope (“love and money await you”).
For centuries Venetian glass factories had been grinding lenses “to improve vision,” to quote Roger Bacon in 1249. By Galileo’s day two low-grade lenses, inserted at either end of a cardboard tube, were being sold as a child’s toy in Venice and elsewhere in Europe. Nevertheless, questions which seemed eternal puzzled people everywhere: What held up the sky? How much does the sky weigh?
An answer came close in October of 1608 when a lens maker in the Netherlands named Hans Lipperhey applied for a patent on a spyglass. This had military importance because it could enable enemy ships to be spotted at a distance, allowing more time to prepare a defense, and so foreign envoys sped the news to their home countries throughout Europe.
The following year English mathematician Thomas Harriot became probably the first to point such a device, armed with lenses to the power of six, at the Moon and then make drawings of what he saw.
Peering into one of the toy devices while visiting Venice in the summer of 1609, Galileo, in his early forties and a little known professor of mathematics, saw that buildings on the horizon were magnified. A Venetian friend, Fra Paolo Sarpi, then told him of Lipperhey’s invention.
Grasping the possibilities, Galileo ordered the best quality lenses Venice could offer, only to discover that all those available were inadequate. Even Lipperhey’s spyglass increased the power of the eye by at most three times. Electing to learn to grind and polish the lenses himself, in the course of a scant few months Galileo “bought the appropriate equipment and slowly trained himself,” according to historian Albert Van Helden of Rice University, in an essay in the excellently translated exhibition catalogue.
Throughout the autumn months Galileo worked at his lenses, first creating one to the power of six and then improving it until he achieved lenses to the power of twenty. At that point in the depths of the winter of 1610 he trained upon the Moon his long and narrow telescope—a telescope covered like the gold-tooled leather souvenir notebooks and bookends sold in Florence today. In so doing he became the first to see the Moon accurately.
A talented water-colorist, Galileo painted what he saw of the Moon in its various phases—and then moved on to show the existence of hitherto unknown sunspots as well as moons circling Saturn. While he was at it, he toppled millennia of philosophical and theological speculation, for his research proved that the Earth moved around the Sun rather than the opposite, as was conventional religious teaching.
“Galileo was perfectly aware of the epochal implications of the phenomena that he, first among men, had observed on those sleepless nights four centuries ago,” says Paolo Galluzzi, director of the Florentine Museum of Science History and prime mover of the exhibition. The Church objected, and in 1633 Galileo was put on trial before an Inquisition court that met, incidentally, in a building a few steps from where I am writing this in Rome; the observatory of the Collegio Romano, where he had lectured, is visible from my window. He was forced to abjure and on grounds of “vehement suspicion of heresy” and sentenced to house arrest at Arcetri near Florence for the rest of his life. He was also forbidden to conduct further experiments that could challenge the theological status quo.
But even these harsh measures, which cost Galileo his continuing work on the skies if not his life, failed to stop others elsewhere from peering through their telescopes. Other intellectual giants followed, including Isaac Newton in England, and the great figures of the Enlightenment. A few years ago the Roman Catholic Church took notice and rehabilitated Galileo, who is expected to be honored with a statue to stand in the Vatican gardens.
The Florence exhibition includes a glass jar containing Galileo’s finger, but what interests us is his mind. Evidence of that are his original telescope and the watercolor drawings he painted showing the phases of the Moon. Projected on a ceiling together with Hubble Observatory photos of the Moon, the overlapping views prove the stunning accuracy of his drawings of four centuries ago.
What went before Galileo is no less fascinating. Examples of astronomical devices and depictions from Mesopotamia and ancient Egypt have been loaned by various British, French, Egyptian, Italian, German, Vatican and other museums. Sundials, water-powered hourglasses, sky and Sun mythological illustrations and astronomical writings illustrate early attempts to understand the Cosmos and to interpret it through scientific instruments as well as myth, poetry, and paintings, including from Pompeii. Medieval Islamic manuscripts, globes and astrolabes paved the way for the Christian evangelization of the Cosmos, documented in manuscript illustrations, in Giovanni Dondi’s 14th c. model of an Astrarium and in paintings by, among others, Sandro Botticelli and Jan Brueghel the Younger.
At the same time, paving the way for Galileo, incredibly complex Renaissance-era astrological instruments such as armillary spheres and planetary clocks, manufactured by the foremost goldsmiths of Europe, show the connection between the applied arts, mathematics and technology.
Galileo, Immagini dell’Universo dall’antichità al telescopio. Through 30 August 2009. Exhibition curator Paolo Galluzzi, Director, Istituto e Museo di Storia della Scienza. Florence. Palazzo Strozzi, Director James Bradburne. Open daily 9 am to 8 pm, Thursday closing 11 pm. 442-page catalogue, Giunti. Special related tours to Galilei sites and activities for children. Technical sponsor Canon.