"Galileo Mystery"

©1995 The Regents of the University of California

Galilean moons of Jupiter, Galilean telescope, Galileo's pendulum, Galilean experimental method, Galileo spacecraft, and even Galileo High School in San Francisco!

What do all these different words have in common? Yes, you are absolutely right, they were named after a famous scientist, an inquisitive person, and an outstanding mathematician, physicist, and astronomer who lived over three hundred years ago.

Let's try to understand why, after so many years, we still remember this man, trust and respect his ideas, study his theories and discoveries, repeat his experiments, and still give his name to different objects and institutions.


Galileo Galilei, who was generally known only by his first name, was born in 1564, in Pisa, Italy. His family belonged to the nobility but was not rich. His father sent him to study medicine at the local university, but Galileo soon turned to a career in physical science and had achieved phenomenal results.

Galileo was an inquiring person who was interested in the world around him and always wanted to know why things were the way they were. By watching a chandelier swing in the cathedral at Pisa, he discodered the law of the pendulum and gave society the first reliable means of keeping time. It happened when he was only nineteen years old.

In three years he attracted the attention of scientists with his discoveries in hydrostatics and dynamics. His work in mechanics won him an appointment as a lecturer on mathematics, first at Academy of Florence, then at the University of Pisa, and later at the University of Padua.


The most substantial part of his work undoubtedly consisted of his establishment of mechanics as a science. The idea of a universal force of gravity led him to the statement of constant gravitational acceleration. Galileo was the first person who declared mathematics to be the language of physics and other sciences.

Galileo created the method of modern experiment with all its phases: hypothesis, analysis, theoretical deduction, etc. He applied this method to check laws of falling objects and the motion of a projectile.

Remarkable results were achieved by Galileo in astronomy as well. For example, after he learned about Hans Lippershey's newly invented telescope, Galileo built his own version of the instrument, but with higher magnification.

Galileo's phenomenal observational skills and his new astronomical telescope led him in 1609-1610 to a series of beautiful and very important discoveries.


He discovered the irregular surface of the Moon with craters and mountains, certainly not as smooth as had been thought until that time. He found hundreds of new stars in the Orion constellation, far more than can be seen by the naked eye. He identified four satellites of Jupiter, constructed accurate tables of their revolutions, and predicted their frequent eclipses.

In addition to this, he discovered sunspots and concluded that the Sun rotated on its axis by noticing movements of the sunspots across the solar disc. He observed Saturn and the phases of Venus. Finally, he proved that the Milky Way was a collection of Stars. Isn't it remarkable? There were enough discoveries for a whole department of scientists, not just one person.


But the life of this scientist was not simple, predictable, or rational. Being as great as he was, Galileo, for example, did not accept Kepler's laws of planetary motion. At the same time, he believed with all his heart in the Copernicus`s theory of the solar system. Because of his personal belief in the heliocentric doctrine, Galileo was heavily criticized by the church, and in 1616 was sentenced by the Inquisition to life imprisonment in his home in Florence.

It was outrageous that a person such as Galileo was forced to spend the remainder of his days in house exile. Nevertheless, he continued to work and write books while in exile. One of the books was the famous "Dialogue on the Two Chief World Systems." Galileo died in 1642 after having suffered blindness in the last four years of his life and leaving his inventions, discoveries, books, and his devotion to science to future generations, that is, to us.


"Galileo" Spacecraft

It is not a coincidence that one of NASA's latest creations was named after Galileo Galilei. The unmanned spacecraft was launched by the United States on October 18, 1989. The Galileo mission is to explore the planet Jupiter by placing a 337 kg (744 lb) probe in orbit around the planet.

The probe is intended to descend into Jupiter's atmosphere, near the equator. The probe is expected to survive for about 75 minutes before being destroyed by intense atmospheric heat and pressure.

It is assumed that this time will be enough for gathering information about the Jovian (Jupiter's satellite found by Galileo) atmosphere - its temperature, pressure, density, chemical composition, and cloud layers.

According to the plan, "Galileo" will reach Jupiter in December, 1995. This NASA mission is considered to be another step in exploring the solar system by getting additional information about the planet which so intrigued and fascinated Galileo.


Galileo High School

There is another example of Galilean great-grand children. This time we are talking about an educational institution named after this famous scientist - Galileo High School in San Francisco.

Built in the 1920's the Galileo High School building was considered an outstanding example of modern architecture. Bounded by Van Ness Avenue, Francisco, Polk and Bay streets, it is located in one of San Francisco's most desirable areas. Galileo High with its breathtaking views of the Pacific Ocean, Golden Gate Bridge, and Alcatraz, draws students from all over San Francisco.

Planned with the idea of housing one of the best educational institutions in the country, it is well equipped to offer a high level of academic curricula that stresses excellence in all areas. Galileo High was also honored by the State of California for outstanding achievements in physics and mathematics performance.


Galileo High School distinguished itself in the statewide and national effort to restructure science education. It offers a compulsory course on conceptual physics to all freshmen and sophomores.

The school is also equipped with outstanding computer labs that allow teachers to implement contemporary teaching techniques. Galileo High School staff and students are now working on the idea of making the school into one of the best public schools in the city in terms of science education. If the plan successful, the school will be renamed "The Galileo Science Academy."

But the most remarkable thing is that Galileo High is the only school in the Bay Area that has its own observatory with a real telescope! The history likes to repeat itself. Who knows, maybe in ten or twenty years another "Galileo," but this time a Galileo Academy graduate, will make remarlable astronomical discoveries, just like his or her famous predecessor did.


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