Galileo Galilei Astronomy

Galileo Galilei Astronomy

Galileo was born in Pisa, Italy in the late 1500′s. He eventually became a mathematics teacher despite having no degree, and it was here that his famous future was first hinted. Galileo the math teacher made his first step into Galileo Galilei astronomy when he demonstrated to his students that Aristotle was wrong about object of different weights falling at different speeds. He wasn’t invited back to teach, and so moved to a position at the University of Padua. His entry into astronomy would come to fruition there.

In Padua, Galileo invented the compass and began studying physics. He discovered the law of falling bodies and the parabolic path of projectiles. These became very important in astronomy, later. But at the time Galileo claimed to have no interest in the subject other than that he believed the work of Copernicus rather than that of Aristotle and Ptolemy. Copernicus had proposed that the solar system is heliocentric, that is that the planets rotate around the sun. Aristotle and Ptolemy held that the solar system was centered around the Earth, and even the sun rotated around our home. The model Copernicus proposed for the order of planets around the sun has been proven. And today we know Copernicus was completely correct.

When the spyglass was invented in Holland, Galileo learned of it and made his own telescope which he turned to the sky. With a magnification of 20, this telescope helped Galileo discover mountains and craters on the moon. He also learned that the milky way was made up of individual stars. He went on to discover Jupiter’s four largest moons. He published his findings and became the court mathematician in Florence. With time freed from teaching duties, he could really get to work. It took him only 9 months to discover Saturn’s phases. This further contradicted Ptolemy while proving that Copernicus was right.

Galileo’s original dispute was with Aristotle’s teachings. Many scientists agreed with Galileo, and so published his findings. But Aristotle was popular with the church because an Earth centered solar system put man’s home, and thus man, at the center of things. In 1614 a priest in Florence denounced Galileo Galilei Astronomy. Galileo responded by writing a letter proclaiming the bible irrelevant to science. In 1616 the church censored Galileo’s books, and a cardinal instructed him to stop teaching that the Earth moves. Galileo complied, continuing his study of falling objects, comets, and methods to determine longitude at sea based on the phases of Jupiter’s moons. It is said that Galileo had one comment after signing an agreement that the Earth does not move. “I would say here something that was heard from an ecclesiastic of the most eminent degree; “And yet … it moves.”