Biography by Peter Landry at blupete.com.
Galileo was an Italian. At the age of 19 he discovered the principle of isochronism
that each oscillation of a pendulum takes the same time despite changes in amplitude. Soon
thereafter he became known for his ideas on hydrostatic balance; and, further, his
treatise on the center of gravity of falling bodies. He found experimentally that bodies
do not fall with velocities proportional to their weights, a conclusion received with
hostility because it contradicted the accepted teaching of Aristotle.
Galileo discovered that the path of a projectile is a parabola, and he is credited with
Newton's laws of motion. In 1609 Galileo constructed the first astronomical telescope,
which he used to discover the four largest satellites of Jupiter and the stellar
composition of the Milky Way, and in 1632 he published his Dialogue Concerning the
Two Chief World Systems, a work that upheld the Copernican
system rather than the Ptolematic
system and marked a turning point in scientific and philosophical thought. Brought
(1633) before the Inquisition in Rome, he was made to renounce all his beliefs and
writings supporting the Copernican theory.
Hypertext narrative of his accomplishments provides photographs and images of Galileo Galilei's inventions. Discusses his main concepts.
Galilei was born in Pisa in 1564, the son of Vincenzo
Galilei, well known for his studies of music, and Giulia Ammannati. He
studied at Pisa, where he later held the chair in mathematics from 1589 -
1592. He was then appointed to the chair of mathematics at the University
of Padua, where he remained until 1610. During these years he carried out
studies and experiments in mechanics, and also built a thermoscope.
He devised and constructed a geometrical
and military compass, and wrote a handbook which describes how to use
this instrument. In 1594 he obtained the patent
for a machine to raise water levels. He invented the microscope, and
built a telescope
with which he made celestial observations, the most spectacular of which
was his discovery of the satellites
of Jupiter. In 1610 he was nominated the foremost Mathematician of the
University of Pisa and given the title of mathematician to the Grand Duke
of Tuscany. He studied Saturn and observed the phases
of Venus. In 1611 he went to Rome. He became a member of the Accademia
dei Lincei and observed the sunspots.
In 1612 he began to encounter serious opposition to his theory of the
motion of the earth that he taught after Copernicus.
In 1614, Father Tommaso
Caccini denounced the opinions of Galileo on the motion of the Earth
from the pulpit of Santa Maria Novella, judging them to be erroneous.
Galileo therefore went to Rome, where he defended himself against charges
that had been made against him but, in 1616, he was admonished
by Cardinal Bellarmino
and told that he could not defend Copernican
astronomy because it went against the doctrine of the Church. In 1622
he wrote the Saggiatore
(The Assayer) which was approved and published in 1623. In 1630 he
returned to Rome to obtain the right to publish his Dialogue
on the two chief world systems which was eventually published in
Florence in 1632. In October of 1632 he was summoned by the Holy
Office to Rome. The tribunal passed a sentence
condemning him and compelled Galileo to solemnly abjure
his theory. He was sent to exile in Siena and finally, in December of
1633, he was allowed to retire to his villa
in Arcetri, the Gioiello. His health condition was steadily declining,
- by 1638 he was completely blind, and also by now bereft of the support
of his daughter, Sister
Maria Celeste, who died in 1634. Galileo died in Arcetri on 8 January
1642. For the family of Galileo, see the genealogical
tree. Within the Museo,
Sala IV is
entirely dedicated to Galileo and his studies; among other things are
preserved the lenses,
plane, the lodestone,
the model of
the application of the pendulum to the clock, several portraits
and a relic.
From the Mac
Tutor History of Mathematics Archives
Galileo Galilei's father, Vincenzo Galilei (c.1520 - 1591), who
described himself as a nobleman of Florence, was a professional musician.
He carried out experiments on strings to support his musical theories.
Galileo studied medicine at the university of Pisa, but his real interests
were always in mathematics and natural philosophy. He is chiefly
remembered for his work on free fall, his use of the telescope and his
employment of experimentation.
After a spell teaching mathematics, first privately in Florence and
then at the university of Pisa, in 1592 Galileo was appointed professor of
mathematics at the university of Padua (the university of the Republic of
Venice). There his duties were mainly to teach Euclid's
geometry and standard (geocentric) astronomy to medical students, who
would need to know some astronomy in order to make use of astrology in
their medical practice. However, Galileo apparently discussed more
unconventional forms of astronomy and natural philosophy in a public
lecture he gave in connection with the appearance of a New Star (now known
supernova') in 1604. In a personal letter written to Kepler
(1571 - 1630) in 1598, Galileo had stated that he was a Copernican
(believer in the theories of Copernicus).
No public sign of this belief was to appear until many years later...
From the Catholic Encyclopedia
Generally called GALILEO. Born at Pisa, 18
February, 1564; died 8 January, 1642. His father, Vincenzo Galilei,
belonged to a noble family of straitened fortune, and had gained some
distinction as a musician and mathematician. The boy at an early age
manifested his aptitude for mathematical and mechanical pursuits, but his
parents, wishing to turn him aside from studies which promised no
substantial return, destined him for the medical profession. But all was
in vain, and at an early age the youth had to be left to follow the bent
of his native genius, which speedily placed him in the very first rank of