SCI - Toward a new Earth and a New vision of Humankind, con't (Lesson)
Toward a new Earth and a New vision of Humankind, con't.
Contributing Factors.
The Structure of the Human Body.
Andreas Vesalius was a Flemish anatomist who challenged and eventually overturned Galen's medical supremacy. Vesalius dissected human bodies and carefully recorded his findings. The sketches and information uncovered during these dissections lead to the publication of his work On Structure of the Human Body. Vesalius also hosted public dissections, though dissections at this time were still illegal.
Side Note: Dissections were not allowed which is one reason why physicians did not have real life experience when entering their practice and why there was such a major misunderstanding of basic human anatomy. Dissections were generally frowned upon up until the 20th century. Medical schools were known to have "grave robbers" on payroll - these people would steal corpses from local graveyards in order for the students to practice in secret.
On the Revolutions of the Heavenly Spheres.
Copernicus was a Polish priest and astronomer who challenged Ptolemy's geocentric system primarily because it was too complex and he felt that there had to be a mathematically better system. He theorized that if the sun was the center of the universe and the earth just another planet in orbit, elaborate explanations would not be necessary to explain inconsistencies. In 1543 he wrote On the Revolutions of the Heavenly Spheres (which was not published until the year of his death as he feared the Church's reaction). Although Copernicus had made progress he was never completely satisfied with his theory knowing that he had really only opened up more questions than he had answered. Copernicus had, however, opened the door for others to follow with new calculations and theories.
Tycho Brahe.
Brahe, as the son of Danish nobles, was expected to have a career in government, yet became fascinated in the skies when a partial eclipse was predicted correctly. After finishing his studies, he returned to Denmark and quickly established himself as one of Europe's leading astronomers.
Brahe was backed by the king of Denmark and thus was able to set up an elaborate observatory. Telescopes had not yet been invented. His observatory was for monitoring the skies by the human eye and noting what had been observed. Brahe was known for being quick tempered and quite arrogant - both of which led to his involvement in many a duel. It was in one of these that he lost the tip of his nose, replacing it with a silver, and sometimes gold, piece. He was a deeply devout Catholic and often attempted to justify his findings with church dogma.
Brahe was an astonishing observer, but not a strong mathematician. For 20 years he observed the night skies and kept close records of those observations. Unfortunately he was unable to mathematically deduce what it all meant.
Johannes Kepler.
Johannes Kepler was the complete opposite of Brahe. The son of a minor German noble, he had been trained to be a Lutheran minister. Yet, he always felt as though the universe was built on mathematical relationships. He transitioned into Astronomy while in school and eventually became Brahe's assistant. The two, however, highly disliked one another, with Brahe keeping the majority of the data locked away from Kepler. Upon Brahe's death, Kepler spent 20 years interpreting the data, leading to the establishment of his 3 laws of planetary motion.
Kepler's 3 law:
- 1609 - the orbits of the planets are ellipses (ovals)
- Planets don't move at a uniform speed in their orbits
- 1619 - the time a planet takes to make it's orbit is precisely related to it's distance from the sun. Kepler noted that the closer an object was to the sun, the faster it moved through its orbit, the further away it was, the slower it moved. His reasonings are explained by the theory of gravity, though gravity had not yet been discovered.
Theories of the Universe.
The leading belief, stemming from the Greeks, was that the universe was geocentric, with the planets revolving in perfect circles.
Copernicus theorized that the universe was actually heliocentric and published his ideas in his work "On Revolutions of Heavenly Spheres."
Brahe, determined to reconcile his religious beliefs with his scientific observations, posited a dual system with the all the celestial bodies (except earth) being heliocentric, and that entire mass circling the earth.
Kepler's theory held that the universe was heliocentric, but that the planets revolved on ellipses.
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