Galileo's Daughter: A Historical Memoir of Science, Faith, and Love

Author: (USA) Dava Sobel (Sobel, D.) wrote, translated by Xie Yanguang
Publisher:
Publishing Date: 2002-03-01
Features: The illustrious Father: The passing of the beloved sister we call our dear aunt has caused us immense grief; but compared to our concern for You, our sorrow for her loss seems insignificant. Now, in Your world, You are truly alone, without companions, and therefore Your suffering will be even greater. Since Your dearest one has left You, the only thing we can imagine is the severe trials You have endured from this sudden, completely unexpected blow. When we tell You that we grieve as deeply as You do, perhaps You might consider the universal suffering of humanity, where You may even find greater comfort, for we are all but fleeting passersby in this world, and soon we shall all go to our heavenly home, where alone there is true happiness. And we must believe that Your sister's blessed soul has already gone there. Therefore, in God's name, we beg You, Father, to seek comfort in God and surrender Yourself to Him, for You know very well that it is God's requirement of You; if You do not, You will only be harmed, and it will also cause us pain, for if we hear that You are troubled and sorrowful, we will be deeply grieved: In this world, besides You, there is no one else who can be an example of virtue for us. I do not wish to say any more, we can only sincerely and fervently pray to God for Your comfort, may God be with You forever, and with our burning love, we send You our warmest regards. May 10, 1623, from San Matteo. Deeply loving Your daughter, Sister Maria Celeste and Livia do not know when they will see their brother Vincenzo again. At least for now, Galileo thought it best to leave the still toddling little boy with Marina in Padua. Shortly after Galileo left Venice, Marina married a respectable citizen named Giovanni Bartolucci, whose social standing was similar to hers. Galileo not only agreed to their marriage but also helped Bartolucci find a job with a wealthy friend of his in Padua. Galileo still sent money to Marina for Vincenzo's living expenses, while Bartolucci supplied Galileo with lens blanks for telescopes, which came from the famous glassworks on the island of Murano within the Venetian, this source lasting until Florence was proven to be an even better supplier of pure glass. Galileo rented a house in Florence, which "had a high flat roof from which the entire sky could be seen," where he could observe celestial phenomena and install grinding machines for lenses. During the waiting period for the keys, he lived with his mother and two little girls for several months in a room he rented from his sister Virginia and her husband Benedetto Landucci. Despite recent legal disputes, Galileo's relatives provided him with a quite warm family environment, although the "harmful air of winter in this city" caused him great suffering. "After being away for so many years," Galileo sighed, "I have encountered the thin air of Florence again, which is a cruel enemy to my head and the rest of my body. In the past three months, colds, bleeding, and constipation have weakened my body, making it frail and listless, and I have actually been confined to my home, or more accurately, bedridden, yet I have not been fortunate enough to sleep, nor have I been able to rest." As far as his health permitted, he devoted his time to studying the problem of Saturn. Saturn is a planet far more distant from Jupiter, and its distance was clearly at the limit of his best telescope's resolution. He thought he saw two large, fixed satellites of Saturn. He described what he saw with a Latin phrase that had its letters rearranged. If the letters were put back in the correct order, the phrase meant: "I have seen a distant planet with three bodies." To announce this as his discovery without causing ridicule before it was properly confirmed, he quickly sent this Latin phrase to several famous astronomers. Yet none of them could decipher it correctly. In Prague, the great Kepler, who now had a telescope and considered it "more precious than the scepter symbolizing royal authority," also misunderstood the message, thinking it meant Galileo had discovered two satellites of Mars. Throughout the autumn of 1610, as Venus appeared in the night sky, Galileo studied the changes in its size and shape. He also kept a telescope aimed at Jupiter for a long time, striving to determine the exact orbital periods of its four newly discovered satellites to further confirm their reality. Meanwhile, other astronomers complained that they had exhausted their efforts to see Jupiter's satellites with inferior instruments but achieved nothing, so they doubted the existence of these celestial bodies. Despite Kepler's support, some maliciously accused that the satellites were almost certainly illusions, perhaps created by Galileo's lenses. Since these satellites had become a contentious issue for the Grand Duchy of Florence, it was necessary to remedy the situation immediately to protect the Grand Duke's honor. Galileo hurriedly made as many telescopes as possible, not only for the princes and nobles of all Italy but also for export to France, Spain, England, Poland, and Austria. "To maintain and enhance the reputation of these discoveries," Galileo argued, "I thought it necessary to show as many people as possible the truth itself, to acknowledge the truth through its very effects." Some famous philosophers, including some of Galileo's former colleagues in Pisa, refused to use telescopes to see these so-called new things in Aristotle's eternal universe. Galileo deflected their scorn with a humorous tone: In December 1610, upon learning of one such opponent's death, he loudly expressed the hope that the professor, though he had once disregarded the Medici stars in his lifetime, might encounter them on his way to heaven. To solidify his position as the one who announced this discovery, Galileo thought it wise to go to Rome, the eternal city, to widely publicize his findings. Before this, he had visited Rome in 1587 to discuss geometric problems with the outstanding Jesuit mathematician Christopher Clavius, who had written some influential commentaries on astronomy and would certainly welcome news of Galileo's recent work. The Grand Duke Cosimo did not oppose this trip, believing it would enhance his status in Rome, as his brother Carlo was then holding the traditional position of Cardinal of the Medici family in Rome. Galileo resisted the temptation for a long time in the autumn of 1618 not to go outdoors to see any of the three comets, which seemed incredible, and it was especially so since he felt perfectly well and could still engage in academic discussions with visitors. But the fact was, the air at night in November was dangerous to him, after all, he was well over fifty, and most of that year he had been fighting one illness after another. Moreover, Galileo undoubtedly knew from his friends' accounts that even if he risked his life to study these objects personally, he would not see much. Even with the highest-powered telescope, the outlines of comets or "hairy stars" remained indistinct. When the telescope filtered out the light of stars, they became mere points of light; if the same treatment was applied to planets, they became small spheres. Comets were different from stars or planets, as they could not be clearly focused. Galileo hesitated because he believed comets were part of the Earth's atmosphere—in this case, he was in agreement with his contemporary Aristotle school, though for different reasons. Galileo thus rejected the discovery of his Danish predecessor Tycho Brahe, who had observed a large comet in 1577 and another in 1585. Tycho was probably the most capable person in the world to observe celestial bodies with the naked eye, and every night he tracked the comet with his enormous measuring instruments to determine its position. Through his study of the position, he found that it was farther than the moon and perhaps as far as Venus, which, for the thinking of the 16th century, meant one of two things: either the comet had crashed into the crystalline sky as Aristotle had said, or these celestial bodies did not exist. Tycho, being the only European in this field, was bold enough to choose the latter hypothesis in 1572 to identify a new star, which convinced him that changes could occur in the unchanging sky. Galileo, having personally witnessed the second new star in 1604, supported the deceased Tycho's explanation of the nature and importance of the new star. But he despised Tycho's planetary system, considering it a clumsy compromise between Ptolemy and Copernicus. As for the comet that Tycho had meticulously tracked, Galileo also dismissed it as a mere phantom. He regarded comets as unusual luminous phenomena in the air—very likely reflections of sunlight by high-altitude water vapor—rather than celestial bodies themselves. Galileo believed that you could not determine the distance of a comet, just as you could not catch a rainbow or control the aurora borealis. Thus, the curtain of the heavens was raised, and several characters had already gathered together, and their conversation immediately turned to the subject. The discussion of this day drew a line between the Aristotelian/Ptolemaic and Copernican worldviews. For this, Simplicio put forward Aristotle's view, that the Earth was fundamentally different from all celestial bodies—because it was composed of elements rather than aether. Galileo's alter ego, Salviati, tried to find a place for the Earth in the sky. And Sagredo, with his innocent nature, endowed the Earth—"the dregs of the universe, a place of filth"—with a unique power born of its own distinctive variability: "As for me, I think the Earth is very sublime, great, and admirable, and this is because of the constant modifications, changes, and generations that occur on it. If the Earth did not undergo any changes, it would be a vast desert or a mountain of jade; or if the large areas of water that flooded it during the flood period had frozen, making it a huge ice ball where nothing could grow and change forever, then I would consider it a dead, worthless piece of the universe, a superfluous, essentially non-existent thing." As for how the Sun changes through solar flares and shrinks around its waist in circles, Salviati supported him with evidence from their "friend's" telescope. He proposed that the Moon and all stars, whether fixed or moving, might also be changing, though such changes had not yet been discovered. Aristotle believed that eternal unchangeability is the defining attribute of perfect celestial bodies, and this claim was completely turned into narrow-mindedness here.