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Galileo was born on February 15, 1564, to Vincenzio Galilei, a nobleman who was talented in math and music but poor in money. He had high ambitions for his son Galileo and wanted him to become a doctor.

When Galileo was young the family moved to Florence, Italy, from Pisa. Here he received his early education in a nearby monastery. In 1581 Galileo was sent to the University of Pisa where he studied medicine. However Galileo had little interest in medicine so he found his classes boring. Despite this lack of interest in medicine his curious and creative mind led him to the world of science.

According to one story he was sitting in the cathedral of Pisa as the lamps were being lit, and he noticed that the lamps swung. He saw that some were swinging in wider arcs than others. Galileo thought that the wilder swings would take more time to stop swinging so he timed the swings against the beats of his pulse. From this he found that they all took the same amount of time. This observation stirred his interest and he began to run experiments at home and worked out the laws governing a pendulum. He then applied this knowledge about pendulums to invent a timing device. This experience had set the pattern of his life. An observation that led to questions and experiments, which in turn led to new knowledge and applications.

He then left medical school before becoming a doctor and returned to Florence. He wrote on physics which made him known and he became a math professor at the University of Pisa. To work out the laws of falling bodies Galileo dropped balls of different weights at the same time from the same height. Historically this supposedly was from the top of the leaning Tower of Pisa. The weights all impacted the ground together which proved Aristotle belief that heavy objects fall faster than lighter ones wrong. In order to determine the speed at which the balls fell, he built an inclined plane. Using this titled board he could control the speed at which the balls moved and was able to do timed experiments with them. However since there were no clocks at this time he let water from a bucket run into a measuring cup. So he determined the time by the height of the water in the cup.

His questioning of Aristotle's accepted ideas made him unpopular so he left Pisa, and moved to the University of Padua where he was free to conduct his research as well as teach.

By 1608 the "spyglass" which had been made by an eye-glass maker in Holland had made it's way to Europe. Upon learning about it Galileo figured out what it could mean to astronomy. So he learned how to make one. When he pointed his glass into the night sky he saw that the moon was not smooth as was commonly thought. Rather it was full of mountains and craters, and the Milky Way was made up of many stars.

In January 1610 he made one of his most important discoveries: the planet Jupiter had moons which revolved around it. However according to Aristotle and other ancients everything revolved around the earth. This was still believed despite the fact that 60 years earlier Copernicus showed that the earth and the other planets circled the sun. Galileo's discovery of Jupiter's moons was just like Copernicus's description of Earth's moon revolving around the earth. This discovery by Galileo was the first evidence that supported Copernicus's theories.

The church at this time was the chief supporter of Aristotle so it opposed the Copernican system. But in 1611 he visited Rome and was given a warm welcome by the Pope. He was allowed to explain and demonstrate his telescope and all there were really impressed with his work. Eventually Galileo published work that supported the Copernican system. His last work was on sunspots, which he and several others had discovered. But Galileo was ordered by the Pope to stop supporting the Copernican system in 1616 when this system was condemned by the church because it was considered an attack on it's teachings. Galileo then promised to obey the Pope's order.

So he left Padua and went back to Florence where he continued with other work. He studied magnetism, worked on some inventions, and perfected the compound microscope. But he just couldn't leave the Copernican system alone, so he went back to it. He was Catholic so he had no desire to fight with the church he belonged to, but the issue at hand was the right of a scientist to seek out the truth.

Galileo's book Dialogue on the two chief systems of the world was published in 1632. The plot of the book involved several people arguing over the different ideas of how the universe worked. In it the winner of the argument was the one who supported the Copernican system.

Galileo was called back to Rome, where he was imprisoned and finally forced to deny his beliefs. He was allowed to return home, but only if he promised to stop writing about astronomy. He returned home where he thought, carried on in his studies and invented new instruments. At this time Galileo also wrote his book on motion and mechanics. He installed for future generations the need and right of scientists to question things. Galileo died in January 8, 1652 still seeking the truth.

   

©Copyright 1998 Elizabeth Beckett, Holly Bernitt, and Vishwa Chandra.