Galileo's observation of the phases of Venus proved that Venus orbited the Sun and supported (but did not prove) the heliocentric model.
Galileo Galilei was born in Pisa, in the Tuscan region of Italy, on February 15, 1564.
In 1609, Galileo was among the first to use a refracting telescope as an instrument to observe stars, planets or moons.
Galileo Galilei, although a staunch Copernicanist, rejected Tycho's measurements and held to the Aristotelean notion of comets moving along straight lines through the upper atmosphere.
Between 1595 and 1598, Galileo devised and improved a "Geometric and Military Compass" suitable for use by artillery gunners and surveyors.
William Gilbert, the great experimentalist who immediately preceded Galileo, did not use a quantitative approach.
The decree did not prevent Galileo from hypothesizing heliocentrism, but for the next several years, he stayed away from the controversy.
By 1616, the attacks on Galileo had reached a head, and he went to Rome to try to persuade Church authorities not to ban his ideas.
Based on this book, which received high praise from both Sir Isaac Newton and Albert Einstein, Galileo is often called the "father of modern physics."
Galileo determined the correct mathematical law for acceleration: the total distance covered, starting from rest, is proportional to the square of the time.
Galileo, however, did perform experiments involving rolling balls down inclined planes, which proved the same thing: falling or rolling objects are accelerated independently of their mass.
Galileo's Principle of Inertia stated: "A body moving on a level surface will continue in the same direction at constant speed unless disturbed."
Later astronomers overruled Galileo's names for them as Medicean stars and called them Galilean satellites.
By the end of Galileo's life, however, it was being superseded by the algebraic methods of Descartes, which a modern finds incomparably easier to follow.
Research into Galileo's unpublished working papers from as early as 1604 clearly showed the validity of the experiments and even indicated the particular results that led to the time-squared law (Drake 1973).
When Galileo examined the Milky Way, he realized that it was a multitude of densely packed stars, not nebulous (or cloud-like) as previously thought.
At a distance of less than a mile, Galileo could detect no delay in the round-trip time greater than when he and the assistant were only a few yards apart.
Nearly 350 years after Galileo's death, Pope John Paul II publicly acknowledged that Galileo had been correct.
Galileo is lesser known for but nevertheless credited with being one of the first to understand sound frequency.
Many commentators consider that Galileo developed this position merely to justify his own opinion because the theory was not based on any real scientific observations.
Galileo had alienated the pope, one of his biggest and most powerful supporters, and was called to Rome to explain himself.
Galileo produced one piece of original and even prophetic work in mathematics, known as Galileo's paradox.
Galileo was one of the first Europeans to observe sunspots, although there is evidence that Chinese astronomers had done so earlier.
Galileo fulfilled only the latter of those requests, using a character named Simplicius to defend the geocentric view.
Galileo and his contemporaries knew that there are two daily high tides at Venice instead of one, and that they travel around the clock.
Galileo, on the other hand, defended heliocentrism and claimed it was not contrary to those Scripture passages.
Galileo's theoretical and experimental work on the motions of bodies, along with the largely independent work of Kepler and Renй Descartes, was a precursor of the classical mechanics developed by Sir Isaac Newton.
Galileo Galilei (February 15, 1564 – January 8, 1642) was an Italian physicist, astronomer, and philosopher, whose career coincided with that of Johannes Kepler.
To add insult to injury, Galileo put the words of Pope Urban VIII into the mouth of Simplicius.
About 1606–1607 (or possibly earlier), Galileo made a thermometer, using the expansion and contraction of air in a bulb to move water in an attached tube.
Galileo made a few contributions and suggested others to what we now call technology, as distinct from pure physics.
The experiments on falling bodies (actually rolling balls) were replicated using the methods described by Galileo (Settle 1961), and the precision of the results was consistent with Galileo's report.
Barberini was a friend and admirer of Galileo and had opposed the condemnation of Galileo in 1616.
Galileo's father, however, had performed experiments in which he discovered what might be the oldest known nonlinear relation in physics, between the tension and pitch of a stretched string.
Galileo would open his shutter, and, as soon as his assistant saw the flash, he would open his shutter.
Upon observing the patterns of light and shadow on the Moon's surface, Galileo deduced the existence of lunar mountains and craters.
On January 7, 1610, Galileo discovered three of Jupiter's four largest moons: Io, Europa, and Callisto.
Concerning his theory on tides, Galileo attributed them to momentum, despite his great knowledge of the ideas of relative motion and Kepler's better theories using the Moon as the cause.
Based on sketchy descriptions of telescopes invented in the Netherlands in 1608, Galileo made an instrument with about 8-power magnification and then made improved models up to about 20-power.
Pope Urban VIII personally asked Galileo to give arguments for and against heliocentrism in the book, and to be careful not to advocate heliocentrism.
Galileo also noted that Venus exhibited a full set of phases like the Moon.