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August 25, 1609 CE – Galileo Galilei Demonstrates the Telescope to Venetian Officals

  • Telescope

    The wealthy city-state of Venice, bustling with trade at all times, had a critical problem:  hostile boats from other seafaring regions attacking merchant ships spreading Venetian goods around the Mediterranean Sea.  In order to help minimize the occurrences of such treachery, an obscure mathematician from the University of Padua named Galileo Galilei stepped forward with an improvement on a relatively new technology in the hopes of selling it to the Venetian Senate.  On August 25, 1609, he presented a modification on a Dutch design for what would go on to become known as the telescope.

    For more than a decade, Galileo had been walking the halls at the University of Padua without much in the way of attention.  Teaching geometry and astronomy alongside theories of motion, he had managed to retain a relatively flat career trajectory until necessity forced him to find a way to generate more income.  The father of a handful of illegitimate children, Galileo found himself in need of a raise or a business venture which would allow him generate revenue.  By modifying spyglasses created in the Netherlands, he found a way to do both – and, in time, change the course of human history.

    The core problem, as far as the Venetian Senate was concerned, was the continued threat the Turks placed on the transfer of goods from the port in northeastern Italy.  Using two lenses wrapped with leather, Galileo took several senators to the top of one tower and asked them to gaze out on boats in the water surrounding the city.  Staggered by the ability to observe the crews in some detail, the Senate scrapped plans to purchase the Dutch version and bought from the native son instead.

    The slim tube, nearly identical to those which Galileo had modified his design from, housed a lens at each end but, using his knowledge of mathematics, he managed to squeeze additional magnification out of the simple device – the viewer saw items eight times larger than they appeared with the naked eye.  Guaranteeing he would come up with improvements that allowed users to see even further, Galileo was financially secure.

    Soon after, he began to use the device to observe the heavens.  Setting his sights on the planet Venus, he noticed moon-like phases – something only possible if the sun were the center of the solar system, a fact counter to the teaching of his beloved Roman Catholic Church.  As if to make his point even more solid, Galileo observed moons orbiting Jupiter and the stars filling up the Milky Way galaxy.

    In 1623, while embroiled in a dispute with a Jesuit priest teaching mathematics at the Collegio Romano, Galileo found himself answering for his “blasphemy.”  Having personally encouraged the Church to avoid declaring Copernicus' teachings untrue and been chastised by the clergy, he knew what was at stake.  In producing Dialogue Concerning the Two Chief World Systems as a defense for his theory, he made a critical error:  he used Pope Urban VIII's own words when describing the dim-witted views of a character defending the earth as the center of the universe.

    Suspected of heresy by the Inquisition, Galileo was sentenced to house arrest in July 1633 and lived out his days at his home in Florence, losing his sight in 1638 and dying in January 1642.

    Last Updated on: July 19, 2012