Recently Grant Martin and myself attended an organizational meeting for the Greater St. Louis Renaissance Faire. We wanted to see if it was possible to have an ASEM presence at the fair with an "e" after it. Their theme date is France in 1518, which was kind of an astronomical black hole. So I began researching what possibly do to participate.. The truth is I found this period of history very interesting, I hope I can make it interesting for you.
This was the time when the popes ruled the world from Rome, but they were losing their power and they knew it. They would not let go of that power easily. Several examples of their control are: You could not be king of your own country without the popes blessing. However this problem could be solved with a large box of cash. Nothing was to be published without church approval. For example, the church was aware of the New Testament. It was considered to be a controversial collection of writings to only be read by scholars. When it was published in the early 1500's in the common language of the people, the man who did it, Erasmus, was hunted down and burned at the stake over a slow fire. It took an unmerciful half an hour for him to die. Yet in 1611 King James would include The New Testament in the Bible that he authorized to be written in the language of the people. Times were changing, though slowly. I hope I have now set the stage for my topic.
There is nothing I can do or say that could convince you today that the Earth was at the center of the universe and the Sun, Moon, five planets and stars all revolved around it. But the idea of an Earth centered universe was adopted by the Church in the thirteenth century. I say adopted because nothing in the Bible states that's the way it was. The idea came from Aristotle and Ptolemy. By the time Copernicus published De Revolutionbus in 1543 the Geocentric system had been the entrenched idea of how the universe worked for over nineteen hundred years and it was the endorsed philosophy of 200 popes. It was considered heresy to believe other wise, and no one was anxious to be the guest of honor at a bonfire. However it was a philosophy that didn't work because there were no physical or mathematical basis for it. You couldn't predict astronomical events using the geocentric system. The movement of the planets were a puzzle, conjunctions of planets were a mystery too. These was important information for astrologers making charts and also the navigation of ships. Ships that were now beginning to sail on long ocean voyages and used stellar navigation to find their way found some of the brightest objects in the sky, the planets, movements unexplainable. Then there was the problem of Easter.
Easter is celebrated on the first Sunday following the Paschal full Moon. That date also determines Ash Wednesday, in the seventh week before Easter, Good Friday, two days prior and Whitsunday, seven week after. To complicate the problem the church had adopted the Julian Calendar, conceived in Julius Caesar's reign, which was out of sync with the seasons. By the beginning of the sixteenth century the Vernal Equinox March 21, by the Julian Calendar, occurred on March 31. These were the problems that mathematicians, like Copernicus, were trying to solve and keep their toes out of the fire. What worked best was the Heliocentric system, it too was an old idea dating back to the third and fourth centuries BC. Heraclides and Aristarchus had proposed it, and Aristarchus was charged with blasphemy for doing so, ruining his reputation. Philolaus also backed it, but Aristotle and Ptolemy had won out partly because it appealed to man's vanity that the Earth was at the center of things, and also it appeared that way to the eye. However, the Heliocentric system didn't work perfectly, and it still relied on epicycles to explain the backward movement of the planets and the planets movements were still thought to be in perfect circles. It would be another 100 years before Kepler would explain that the planets moved not in circles but in an ellipse and write the formula that allowed other mathematicians to be able to predict their movement too.
Copernicus delayed publishing not because he was afraid of being punished by the church, so much as he was a perfectionist. Even after thirty years of working on his theory he didn't think it was ready to be published. There was someone who thought he should publish and pushed him to do so. A young man named George Rheticus came to visit Copernicus and wound up staying for two years. The first edition was brought to Copernicus when he was on his death bed.The publisher too was reluctant to say that Copernicus backed the Heliocentric system, but printed a disclaimer in the front of the book that Copernicus had meant this as a mathematical model to make predictions.
The Geocentric system would live on into the mid seventeenth century and even then there were attempts to revive it.
Feb 1 - 15 Look for the Zodical light about an hour and twenty minutes after sunset. It's faint glow can be seen along the Ecliptic.
02 Candlemas, we are half way from the winter solstice and the equinox.
03 Spica and Saturn are above the gibbus Moon around midnight.
05 Last quarter Moon.
06 Antares rising under the crescent Moon at dawn.
11- 12 The thin crescent Moon and Mercury can be seen with binoculars low in the dawn sky. About 30 min before sunrise.
13 New Moon.
14 At dusk look for Venus, Jupiter and the crescent Moon at low in the sky in the west.
15- 18 Venus and Jupiter very close in the sky near the horizon at sunset.
21 First quarter Moon.
25 Mars near the gibbus Moon.
28 Full Moon.