400 Years of Galileo: Myths, Facts and Influence of a Renaissance Man
June 10, 2009
BLOOMINGTON, Ill. – Galileo Galilei has been called the father of modern astronomy,
the father of modern physics and the father of modern science. As the international
science community celebrates the 400th anniversary of Galileo turning his telescope
to the skies, Illinois Wesleyan University Professor of Physics Linda French talked
about the continuing influence of this Renaissance man.
“Anyone who has ever taken physics, or even looked through a telescope, has some knowledge
of Galileo’s findings,” said French, of the man who discovered four moons of Jupiter,
and promoted the idea that the earth was not the center of the universe.
It was the latter idea that ran Galileo into trouble with the Inquisition. “I think
more people remember him for his problems with the Inquisition than his mathematical
interpretation of physical properties,” she said. “Whether he wanted to or not, he
fought a battle that had to be fought.”
Myth or Reality?
Galileo invented the telescope.
Myth: Though he was one of the first people to publish findings based upon research done
with his telescope, Galileo did not invent it. Credit has gone to Hans Lipperhey,
a Dutch eyeglass maker.
Galileo discovered sunspots.
Reality: Galileo was the first to see sunspots through his telescope and record them. In
fact, looking for them may have contributed to his loss of sight in his later years.
Galileo gave the large, dark area on the moon the name of “maria.”
Reality: When he looked at these areas through his telescope, he saw that they were smooth
and thought they were large seas. He thus gave them the Latin name for sea – maria.
Today, we know they are old lava flows.
That battle began over Galileo’s research conducted in 1609, which he published the
following year in a pamphlet called The Starry Messenger. By the time of its publication, a number of those studying the stars acknowledged
that the earth was not the center of the universe, which had been proposed by the
ancient philosopher Aristotle. “Aristotle’s physics were terrible,” said French, with
a laugh. “And anyone who took the trouble to examine it realized this.”
The trouble was, said French, Aristotle's teachings had been incorporated into the
theology of the Catholic Church through men like St. Thomas Aquinas. So to question
them was to question humanity’s place as the center of God’s universe, and was tantamount
to heresy. “A battle had to be fought to separate Aristotle’s theology and Aristotle’s
physics,” she said.
Nearly a century before Galileo, mathematician Nicolaus Copernicus had published a
“heliocentric” view of the galaxy – claiming the planets revolved around the sun.
His work did not cause great uproar at the time. When Copernicus published his works,
he wrote in Latin, so only a few scholars could read it. He also phrased it as a theory,
not a direct challenge. Unlike Galileo. “Galileo seems to have had a talent for alienating
people. He was smart and he wasn’t going to be shy about it,” said French. “He did
not write it in Latin, which was the language of the scholars, but in Italian. Nor
did he phrase his findings as theory.” Instead, he questioned Aristotle’s findings
on gravity and its effects on heavenly bodies, using practical experiments that are
still employed today.
Myth or Reality?
Galileo was a court scientist. Myth: People didn't become scientists back then, so he became a mathematics professor.
He did, however, try to solicit financial support from the wealthy Medici family by
calling his Jovian satellites he discovered the “Medicean stars.”
Galileo’s father wanted him to become a doctor.
Reality: Galileo came from impoverished gentry. His father, who is credited as being one
of the founders of modern opera, wanted his son to have a steady income.
“Galileo was out in the field, disproving Aristotle’s physics," said French. He also
turned his theories of gravity to the skies using the brand new tool of a telescope.
“People warned him, ‘Hey, Galileo, you might not want to do this,’ but I think he
believed it was so obvious he was right that he thought he could convince people,”
she said. “He had a way of throwing down the gauntlet.”
The gauntlet was thrown once again in 1632 with the publication of Galileo’s Dialogue Concerning the
Two Chief World Systems, in which two characters discuss whether the universe is based upon the geocentric
(earth-centered) views of Aristotle, or the heliocentric (sun-centered) views of Copernicus.
“This time he published it as if the arguments are a dialogue between two characters
where the wise Copernicus scholar defeats the foolish Aristotle supporter with his
wisdom, ” said French, “but the dialogue is supposedly taken directly from conversations
with his friend, Bishop Maffeo Barberini, who became Pope Urban VIII. You can’t tweak
the nose of the pope and expect leniency.”
Near the end of his life, under the threat of torture, Galileo did recant his findings
to the Inquisition, an ending that is ironic now as the Catholic Church supports scientific
exploration. Yet Galileo’s battle opened up the doors to modern science. “When following
Aristotle unquestioningly, there was no connection with reality, no experimentation.
As long as that mind-set held, there could be no modern science,” said French. “This
really bothered Galileo. He also developed the mathematical interpretation of physical
properties that we use today. In many ways, he was the first real modern scientist.”