Galileo Galilei, 1564-1642

It is the 400th anniversary of Galileo's telescope, a moment defined as the beginning of the end of the childhood of mankind, a moment when our eyes where opened to the truth of the universe.

Galileo had lived a long and very productive life before he revolutionized astronomy by turning a telescope to the sky. He learned medicine and mathematics at the University of Pisa and became an able instrument builder. He performed many experiments in the motion of bodies and convincingly toppled some of Aristotle's notions, most notably the notion that heavier objects fall faster. Galileo proved soundly that all falling objects fall at the same rate, regardless of mass.

While a professor of mathematics at Padua, Galileo heard descriptions of a recent Flemish invention, the telescope, built with two convex lenses. Galileo worked out the geometry of this arrangement and built a telescope that magnified objects by a factor of ten. After getting a pay raise for this, he designed a more powerful version and pointed it at the sky, thereby changing astronomy forever.

"The moon was seen to have mountains, craters, and sea-like dark smooth areas. The sun had blemishes, or sunspots. The planets were seen as disks! The stars remained point-like. Venus showed phases like the moon. Jupiter had four moons, the inner ones revolving faster than the outer ones."

Around 1611, Galileo ran into some trouble with the Church, which had embraced the Aristotlean cosmology. He was made to promise not to publish anything that implied that the Copernican view was real. He was careful to keep any remarks on the correctness of the Copernican sun-centered view repressed or expressed hypothetically until 1632, when, emboldened by good relations with the pope and some cardinals, he published his "Dialog on the Great World Systems" which was blatantly pro-Copernican.

In 1633, at age 70, Galileo was ordered to stand trial on suspicion of heresy. The sentence of the Inquisition was in three essential parts:

Galileo was found "vehemently suspect of heresy," namely of having held the opinions that the Sun lies motionless at the centre of the universe, that the Earth is not at its centre and moves, and that one may hold and defend an opinion as probable after it has been declared contrary to Holy Scripture. He was required to "abjure, curse and detest" those opinions.

He was ordered imprisoned; the sentence was later commuted to house arrest.

His offending Dialogue was banned; and in an action not announced at the trial, publication of any of his works was forbidden, including any he might write in the future.

It took nearly 400 years but, on November 4, 1992 Pope Paul II issued a formal and public apology concerning the treatment of Galileo saying, "The error of the theologians of the time, when they maintained the centrality of the Earth, was to think that our understanding of the physical world's structure was, in some way, imposed by the literal sense of Sacred Scripture...."

Religion should embrace science, to seek the truth is to seek god, there is nothing to be gained by replacing truth with belief.

(excerpts from astro.wsu.edu and wikipedia.org)