Part 1
Before Galileo, many greased the pathway towards irreverence.
By the turn of the seventeenth century, the integrity of traditional Christian worship seemed wholly threatened by some secular and not-so-secular taunts. The faith had taken some severe hits, and the blows were dealt from all sides. From within the Catholic church came an inappeasable dissident named Martin Luther. His successful protestations forever undermined the dreams of Antioch's Saint Ignatius and his divine vision of a wholly catholic, or "universal" Christian church. From Luther's protests came Protestantism; and thus began the second great schism in Christianity. Dramatists transformed their efforts from the reverential Miracle Plays into the Elizabethan and Jacobean dramas. What such authors as Thomas Kyd, Christopher Marlowe, John Webster offered was some of the most wildly violent and blood-soaked exhibitions since the Senecan dramas of Imperial Rome. Even the honoured William Shakespeare enjoyed this apparent deviation from Christian temperance with his early revenge drama named Titus Andronicus.
From the rediscovered works of Aristotle and other Greek philosophers, men like Francis Bacon and Michel de Montaigne mused of a philosophy emphasizing pragmatism in addition to (as sometimes in place of) the absolute commandments of the Holy Writ.
In the midst of this impious, scientific circus came another gentleman to lend his provocative voice to this chorus. Galileo Galilei, an Italian mathematician, philosopher, and devout Christian, compiled and published his extraordinary stellar observations in a small volume entitled "Sidereus Nuncius," or "The Sidereal, (or Starry), Messenger." Sidereus Nuncius is presented by the author to instruct his audience and not to overwhelm them. The underlying objective of his book is to impart that which he simply observed through his telescope and detailed these observations for all to consider; or, rather, all who could manage Latin.
Galileo observed several stunning celestial details. Certainly one of the most fascinating discoveries concerns the topographical distinctions of our nearest celestial neighbor, the Moon. No longer believed a smooth round orb, the moon is now observed to be a mountainous satellite possessing valleys, plateaus, and multiple impact craters.
Galileo notes that Jupiter, our largest hydrogen-based neighbor next to the Sun, has orbiting her apparent surface four small points of light. These natural satellites, or moons, were the largest distinguishable satellites at the time and were named collectively as the Galilean moons: Io, Europa, Callisto, and Ganymede.
This observation in itself suggested that Earth was by no means the center of all the universe. Here was a celestial body, much, much larger than our own planet, owing a claim to - not one - but four satellites! Galileo states that this fact above all others provides unequivocal support for the "Copernican model" of our solar system. The Copernican model of our solar system was devised by 16th century Polish astronomer Nicholaus Copernicus. At an early age, Copernicus became interested in astronomy and published his description of a "heliocentric" solar system in 1512. In this model, the sun was the center of the solar system.
Though controversial, it was not a new theory and had originally been considered 2000 years before Copernicus by Aristarchus, a Greek philosopher and mathematician. Though Aristarchus was too long dead to be criticized and persecuted by the Catholic authorities, he was viciously attacked by Athenian priests as well as supporters of Aristotle because this theory conflicted with the Aristotelian "geocentric model" of the universe. Borrowing from Copernicus, who in turn borrowed from Aristarchus, Galileo made further discoveries sprouting from his heliocentric universal model. He discovered that our nearest non-lunar celestial neighbor, Venus, exhibited phases just like those clearly exhibited on Earth's moon. This observation lent support to his own support of the Copernican model. He hypothesized that the full and crescent views of Venus are shadows created by - not Earth - but the Sun. Apparently, Venus was orbiting - not Earth - but the Sun.
In regard to the Sun, Galileo's constant observances produced two results. The first was to discover blemishes on the sun's surface today known as sunspots. This seemingly small discovery lead to the greatest of those noted in Sidereus Nuncius. The spots, he observed, apparently moved across the face of the Sun. From this subtle solar attribute, Galileo appropriately inferred that the Sun rotated on an axis perpendicular to the ecliptic (or, the approximate plane upon which all plants fall during their solar orbits) about one time every month.
With respect to the second result of his constant solar observances, by old age, Galileo Galilei was entirely blind. The years of unshielded observances of our sun had destroyed Galileo's eyesight. Clearly, even a brilliant man can have staggeringly lapses in judgement.
