The works of Johannes Kepler on optical phenomena can be considered the beginning of optics as a science. In his works, he outlined geometric and physiological optics, described the General theory of lenses, light refraction, refraction, and the concept of an optical image. Kepler also discovered the role of the human lens for the first time, describing the causes of myopia and farsightedness, and an in-depth study of optical laws led Kepler to the scheme of a telescopic telescope (Kepler telescope).
Craters on the moon and Mars, a supernova, an orbiting Observatory, and a spacecraft were named in memory of the great scientist.
GALILEO GALILEI
Galileo was born in 1564 in Pisa and belonged to a ruined Florentine family. From an early age, the boy was attracted to art; all his life he was interested in music and drawing – he mastered them perfectly. In 1581, 17-year-old Galileo, at the insistence of his father, entered the University of Pisa to study medicine, but was passionately interested in geometry, and in 1592, Galileo received a place at the prestigious and rich University of Padua, where he taught astronomy, mechanics and mathematics. After learning about the invention of the telescope in Holland, Galileo decided to build his own telescope. In 1609. he assembled the first telescope and pointed it at the sky. Soon he was able to build a telescope that gives a magnification of 32 times. It is also important to note that the term “telescope” was introduced into science by Galileo. Using the telescope, which became the main instrument of all astronomers, Galileo Galilei saw the surface of the moon and discovered mountains and craters on the moon, and the milky Way broke up into separate clusters of stars. But even more surprisingly, Galileo was able to see as many as four moons of Jupiter. In Florence, Galileo continued his scientific research, discovering the phases of Venus, spots on the Sun, and then the rotation of the Sun around its axis.
Galileo was a very versatile man, who invented hydraulic scales, studied probability theory, created a prototype microscope with which he studied insects; also worked on the theory of color and magnetism, the resistance of materials, optics and acoustics. He was the first to experimentally measure the density of air. Galileo was a gifted writer and philosopher, and he was certainly the founder of both experimental and theoretical physics, and even Einstein called Galileo “the father of modern science”. He can be considered one of the founders of mechanism, because it is the analysis of mechanical movement that underlies his work. This scientific approach considers the Universe as a large mechanism, and complex natural processes as combinations of the simplest causes, the main of which is mechanical movement.
As you know, Galileo studied inertia and free fall, and in his last book formulated the laws of fall: “The speed increases in proportion to time, and the path increases in proportion to the square of time.” This contradicted the famous statements of Aristotle that the speed of falling is greater the greater the weight of the body. However, with the Catholic Church, things did not go so smoothly for Galileo. The fact is that the absolute majority of his works contained a variety of different statements and hypotheses that completely contradicted Aristotle, namely, the works of Aristotle built the medieval worldview. Seeing the obvious refutations of the geocentric system of the world and its fallacy, he decides to fight for the truth with the Catholic Church. His books violated the prohibition on promoting the “Pythagorean” doctrine, and Galileo was faced with a choice: either he would repent and renounce his “errors”, or he would suffer the fate of Giordano Bruno. Galileo confirmed that he agreed to recite the required recantation, and then was sentenced to prison. He spent the rest of his life under house arrest and the constant supervision of inquisitors. Galileo Galilei died on January 8, 1642, at the age of 78, in his bed. Pope Urban forbade the burial of Galileo in the family crypt in Florence. The greatest scientist of the middle Ages was buried without honors, and the head of the Catholic Church also did not allow to erect a monument. Officially, the Vatican rehabilitated Galileo Galilei only in 1992.
Among the most famous students of Galileo are Torricelli, who became a physicist and inventor, Castelli, the Creator of hydrometry, and Borelli, the founder of biomechanics. Craters, satellites, asteroids, and a NASA space probe were named in memory of the great scientist of the middle Ages.
ISAAC NEWTON
On Christmas night, 1642, a weak and quiet baby was born in the village of Woolsthorpe, named Isaac. Relatives did not baptize the baby at first, because they were afraid that the premature baby would not recover. Isaac’s mother was a widow, and he grew up without friends, and did not participate in noisy games that required skill and physical strength. Even as a child, he built a kind of water clock that measured time so accurately that soon the whole family began to use it. In 1655, 12-year-old Newton was sent to study at a nearby school in Grantham, where he lived in the house of an Apothecary. From the first lessons, the boy showed outstanding abilities. Isaac preferred all other pursuits to writing poetry, reading books, and constructing various mechanisms. In his youth, Isaac passionately devoted himself to writing poetry. After completing his education at school, Newton was able to continue his education at the University of Cambridge. More than 30 years of Newton’s life are associated with this educational institution. The basics of many Sciences were given to Newton without much difficulty, but despite the discoveries of Galileo, natural science and philosophy, Cambridge still taught according to Aristotle. After passing the exams, Isaac received a scholarship, but according to the memoirs of a roommate, Newton completely devoted himself to learning and science, forgetting food and sleep, and probably this is the way of life the young scientist desired for himself. By the age of 23, Isaac Newton was already considered a brilliant mathematician who made a number of discoveries.
In 1664, the plague began in England, and Isaac went to Woolsthorpe, taking with him all the tools and medicines. For three years, according to official data, about 30 thousand people died in London alone. But Isaac was able to find profit in this solitude, and in two plague years Newton made three of his major discoveries: the law of universal gravitation, an explanation of the nature of light, and methods of differential and integral calculus.
We can not help but say, perhaps, about the most famous Apple that fell next to the great scientist, prompting him to study the laws of falling. All his life, Newton was inspired by the great minds of the past – Descartes, Galileo and Kepler, and many of his works are based on their work. Conducting optical experiments, Newton built a mixed telescope-reflector, which in addition to its large size gave a 40-fold magnification. Rumors of the new instrument reached London, and after demonstrating his invention to the king, Newton became famous and in January 1672 was elected a fellow of the Royal society. Later, it was with an improved model of the Newtonian telescope that other galaxies, the planet Uranus, and redshifts were discovered. By 1687, Newton’s main work was published – “Mathematical principles of natural philosophy”, in which he summed up all his works, forming the law of universal gravitation, which described the gravitational interaction, and the three laws of motion.
The law of universal gravitation States that the force of gravitational attraction F between two immaterial points with masses m
and m
separated by a distance r acts along the line connecting them, is proportional to both masses and inversely proportional to the square of the distance.
Three laws of motion:
Newton’s first law: “Every body continues to be held in its state of rest or uniform and rectilinear motion, until and insofar as it is not forced by applied forces to change this state.”
Newton’s second law: “In an inertial frame of reference, the speed of change in the momentum of a material point is equal to the resultant of all external forces applied to it.”
Newton’s third law: “Action always has an equal and opposite reaction, otherwise – the interaction of two bodies on each other are equal and directed in opposite directions.”
These laws helped answer the question about the hypothetical acceleration of The earth’s satellite. Newton knew that the acceleration of the moon in orbit is 0.27 m/s
, and the degree of its orbit is 60 times the radius of the Earth. According to his calculations, the acceleration of a low satellite, that is, all objects on Earth, should exceed the acceleration of the moon by 60
= 3600 times. Using the law of gravity, Newton multiplied 0.27 by 3600 and obtained the famous acceleration of gravity g, equal to 9.8 m/s
.
In 1689 Newton was first elected to Parliament, and again in 1701. Isaac performed his parliamentary duties with the same conscientiousness with which he handled all matters. Written by Newton in 1704, the book “Optics”, in which he described the seven colors of the rainbow as the main colors of the spectrum, became the basis of this field of physics for the next hundred years. For his contribution to the development of science, the English Queen made Newton a knight. Isaac Newton was a very versatile man – in addition to physics, astronomy, and mathematics, he studied alchemy, theology, optical phenomena, and the theory of the ether (a hypothetical all-pervading medium). It was Newton who came up with the idea of making the edges of coins ribbed so that fraudsters could not cut off pieces of metal from them. Despite poor health in childhood, Isaac Newton lived for a full 84 years, dying in 1727, he was not married and left no descendants, but his students and followers made great discoveries in many areas of science.
PIERRE SIMON LAPLACE
For his many achievements in astronomy, physics, and mathematics, Laplace was nicknamed the French Newton. Pierre Simon Laplace was born in 1749 in the family of a farmer in Normandy. In 1765, Laplace entered the University of Caen. The first work of Laplace was associated with the theory of gambling. In the autumn of 1770, having given up his career as a priest and decided to devote himself to science, Laplace came to Paris. In 1773, he was admitted to the Paris Academy of Sciences, and in the same year his fundamental work was published – “On the principle of universal gravitation and on the age-old inequalities of the planets that depend on it”. Laplace was one of the first to openly declare that there should be no God in science, even if you believe in him. Because of the beginning of revolutionary unrest in France, Laplace was forced to flee Paris. In the small town of Melun near Paris, Pierre Simon wrote a book “Exposition of the system of the world”, in which he collected all the astronomical knowledge of the XVIII century, without using a single formula. But the main thing – in this book, Laplace presented his hypothesis of the origin of the Solar system. He suggested that the Solar system was born out of a hot gas nebula that surrounded the young Sun. As it cooled, the nebula began to shrink, and due to the rapid rotation, the centrifugal forces became comparable to gravity, and the nebula flattened, becoming a disk that began to break into rings. The matter in each ring began to thicken, becoming a protoplanet. This theory has existed for more than 100 years, but had a number of significant drawbacks. Also in his book, Pierre Simon came to the conclusion that there are bodies in the Universe with such a huge mass that even light can not leave them. Such bodies are now called black holes. Despite the armed coups in France, Laplace continued to work hard, becoming a member of most of the European academies, and in 1808, he became a member of the French Academy of Sciences. Napoleon, as Emperor, gave Laplace the title of count of the Empire. After the fall of Napoleon and the restoration of the Bourbon dynasty, Laplace received the title of Marquis, became a peer of France, and was awarded the highest order of the Legion of Honor. In 1827, Laplace fell ill and died at the age of 77. His last words were: “What we know is so insignificant compared to what we don’t know.”
WILLIAM HERSCHEL
In observational astronomy, William Herschel can be called Columbus, because he was the first with his telescope to go beyond our galaxy, expanding the Solar system and “moving” the Sun. William was born in 1738 in Germany in the family of a musician of the Hanoverian guard. From the age of 15, he played in the same orchestra on the violin, organ and oboe, the latter of which is the most complex instrument. In 1757, when the seven Years’ war began, the Anglo-Prussian army was defeated at the battle of Hastenbeck, and Herschel fled to England, for which he was accused of desertion. Herschel changed his name to English and quickly learned English. His musical interest led him to mathematics, which led him to optics, and optics to astronomy. From the age of 35 to the end of his life, he devoted himself entirely to astronomy. His observations of cosmic double stars and numerous works laid the Foundation for the modern theory of double stars. In 1781 William Herschel discovered a new planet in the Solar system – Uranus, for which he received the Copley medal, which is considered the oldest and most prestigious award of the Royal society of London, and in 1782 was awarded the Copley medal. He was given the title of astronomer by the king.
12-meter focal length telescope
Having assembled dozens of advanced telescopes, the largest of which is a 12-meter focal length telescope, Herschel studied deep space objects, discovering more than 2,400 such objects, known as nebulae. In addition to Uranus, Herschel discovered four other objects in the Solar system: in 1789, two moons of Saturn, Mimas and Enceladus, and in 1787, two moons of Uranus, Titania and Oberon. Herschel was the first to express the idea of the evolution of cosmic matter under the influence of gravitational forces. For almost 40 years, he observed sunspots and recorded their number, shape, and size. Herschel also hypothesized that the milky Way has the shape of a disk, and the Solar system is part of it. Later, the incredible fact was established that in addition to the movement of all the planets around the Sun, the Sun itself moves around the center of our galaxy at a speed of about 200—220 km/sec. In 1800, studying solar filters, Herschel discovered infrared radiation, the use of which later became the Foundation in medicine related to tissues, in pasteurization of products, protection of premises and night vision devices. The great scientist died in 1822, having lived 83 years, and on his tombstone it is written: “Broke the bolts of Heaven.”
CAMILLE NICOLAS FLAMMARION
When we study great scientists, we first look at their discoveries and achievements, and how we can take advantage of them. Camille Flammarion was the founder of the French astronomical society, and his most important scientific achievements are related to the observation of double and multiple stars, as well as the study of Mars. He wrote the famous book “the planet Mars and its habitat”, which contains all known observations and which is still used by many scientists, and also studied the earth’s atmosphere, climate and volcanoes.
Camille Flammarion was born on February 26, 1842 in a poor family in the small town of Montigny-Le-Roi in France. When the family moved to Paris in 1853, Camille became a gravel apprentice, gaining drawing skills. Despite the fact that Flammarion did not receive a higher education, from the age of 16 he already worked as a cruncher at the Paris Observatory. For 60 years, Camille Flammarion compiled and regularly published monthly maps of the sky showing the location of the planets, and held monthly scientific conferences and meetings. Major works of Flammarion have gone through dozens of editions, sold hundreds of thousands of copies, have been translated into absolutely all European languages and brought the author a great reputation. The great French scientist died in 1925 at the age of 84, and in memory of the contribution he made, craters on the moon and on Mars, many asteroids and an entire Observatory were named after him.
ALBERT EINSTEIN
Albert Einstein – one of the greatest thinkers of all time, it is with his name associated with the completion of the formation of classical physics, which began Newton and Galileo. Despite the fact that Einstein had visited many of the world’s largest observatories, his “tool” was not astronomical tubes, but theoretical thinking. The ideas that Einstein gave to science freed it from outdated philosophical doctrines and beliefs.
Albert Einstein was born on March 14, 1879 in the Bavarian city of Ulm. As a child, the future genius of Einstein did not manifest itself in any way, albert was a reserved and quiet boy who was only able to repeat short phrases by the age of seven. When, at the age of 12, albert read a random book on geometry, he realized the beauty of mathematics. Albert inherited his musical ability from his mother, and his logical thinking came from his father. At school, Einstein openly expressed dissatisfaction with the system in which he studied and which raised an obedient “herd animal”. His homeroom teacher said that albert should leave school because his mere presence in the classroom completely undermines respect for teachers. In 1895, at the age of 16, Albert left the gymnasium. He tried to enter the Polytechnic school in Zurich, known for its high level of teaching, but because of the failure in the exams in history and foreign languages, Аlbert had to re-pass the exams, and in 1896 he entered the Polytechnic, determined to become a teacher of physics. As a student, Einstein did not forget about music, because it was in the classical masterpieces of great musicians that he saw the harmony that he was looking for when building his theories. In 1900 Einstein passed the exam to receive a diploma of teacher of physics, but the work received only two years later. 1905 was the most successful year for Einstein, because he managed to publish five articles that were masterpieces of scientific thought. His hypotheses about light quanta-elementary particles of electromagnetic radiation allowed to explain the appearance of current when a substance is illuminated by short-wave radiation. Despite the fact that this effect was discovered in 1886, it did not fit into the framework of wave theory. It was for this work that Einstein received the Nobel prize, and this work marked the beginning of a new quantum era in the development of physics.
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