"Kepler's laws" - this phrase is familiar to everyone who is fond of astronomy. Who is this person? The connection and interdependence of what objective reality did he describe? Astronomer, mathematician, theologian, philosopher, the smartest man of his time Johannes Kepler (1571-1630) discovered the laws of planetary motion in the solar system.
The start of the journey
Johannes Kepler, a native of Weil der Stadt (Germany), came into this world in December 1571. Weak, with poor eyesight, the child overcame everything to win in this life. The boy's studies began in Leonberg, where the family moved. Later, he moved to an advanced institution, a Latin school, to learn the basics of the language, which he intended to use in future publications.
In 1589 he graduated from school at the Maulbronn monastery in the town of Adelburg. In 1591 he entered the university in Tübingen. An effective educational system was created by the dukes in the wake of the introduction of Lutheranism. With the help of grants and scholarships for the poor, the authorities tried toto provide universities with applicants who could be trained into well-educated clerics capable of defending the new faith in times of raging religious controversy.
During his stay at the educational institution, Kepler came under the influence of Professor of Astronomy Michael Möstlin. The latter secretly shared the views of Copernicus regarding the idea of a heliocentric (Sun in the center) Universe, although he taught students "according to Ptolemy" (Earth in the center). Deep knowledge of the ideas of the Polish scientist aroused in Kepler a great interest in astronomy. So the theory of Copernicus had another supporter who sought to personally comprehend the laws of motion of the planets around the Sun.
The solar system is a work of art
Oddly enough, the one who later discovered the laws of planetary motion did not consider himself an astronomer by vocation. Throughout his life, Kepler believed that the solar system is a work of art, overflowing with mystical phenomena, he dreamed of becoming a priest. The astronomer explained his interest in the theory of Copernicus by the fact that before drawing conclusions from his own research, he must study different opinions.
Nevertheless, university teachers spoke of Kepler as a student with an excellent mind. In 1591, having received a master's degree, the scientist continued his studies in the field of theology. When they were close to completion, it became known that a professor of mathematics had died at the Lutheran school in Graz. The University of Tübingen recommended that a talented in all areas be recruited for this position.graduate relationship. So, farewell to the laws of planetary motion?
In the name of God
22-year-old Johann reluctantly gave up his original calling as a priest, but nevertheless took up the duties of a mathematics teacher in Graz. While lecturing in his class, the novice teacher depicted on the blackboard some geometric figures with the participation of concentric circles and triangles. And suddenly the thought dawned on him that such figures reflect a certain fixed ratio between the sizes of two circles, provided that the triangle is equilateral. What is the area ratio between the two circles? The thought process was gaining momentum.
A year later, an unusual theologian published his first work, The Mystery of the Universe (1596). In it, he outlined his creative views on the secrets of the universe, backed up by religious beliefs.
He who discovered the laws of planetary motion did it in the name of God. Revealing the mathematical plan of the Universe, the researcher came to the conclusion: six planets are enclosed in spheres, between which five regular polyhedra fit. Of course, the version was based on the "fact" that there are only 6 celestial bodies. Around the orbit of the Earth, Kepler outlined a perfect dodecahedron and a sphere touching the orbit of Mars.
Perfect polyhedra
Around the region of Mars, the scientist depicted a tetrahedron and a sphere adjacent to the orbit of Jupiter. In the icosahedron in the orbital sphere of the Earth, the sphere of Venus "fits" perfectly. Using the resttypes of perfect polyhedra, the same was done with the rest. Surprisingly, the ratios of neighboring planetary orbits, presented in the nested sphere model of Kepler, coincided with the calculations of Copernicus.
Discovering the laws of planetary motion, the priest with a mathematical mind relied primarily on divine inspiration. He had no real basis for arguments. The significance of the treatise "Secrets of the Universe" lies in the fact that it was the first decisive step towards the recognition of the heliocentric system of the world set forth by Copernicus.
Assumptions vs high accuracy
In September 1598, the Protestants in Graz, including Kepler, were forced out of the city by the Catholic rulers. Although Johann was allowed to return, the situation remained very tense. In search of support, he turned to Tycho Brahe, a mathematician and astronomer at the court of Emperor Rudolph II. The scientist was known for his impressive collection of planetary observations.
He knew about the work "The Secret of the Universe". But when in 1600 its creator arrived at the Tycho Observatory, located outside the city of Prague, Brahe, who was engaged in high-precision (at that time) research, welcomed him as the author of a specific work, but not as his colleague. The confrontation between them continued until the death of the Danish astrologer, which occurred a year later. After the departure of the rival to another world, Kepler was entrusted with guarding the treasury of his observations. They greatly helped the researcher to become the one who discovered the laws of motionplanets around the Sun.
The Path of Mars
Brage's latest research to create a table of planetary motions has not been completed. All hopes were pinned on a successor. He was appointed imperial mathematician. Despite a tense relationship with a deceased colleague, Kepler was free to pursue his own interests in astronomy. He decided to continue his observations of Mars and describe his own vision of the orbit of this planet.
Johann was sure: by opening the complex Martian path, it is possible to reveal the paths of movement of all other "wanderers of the Universe." Contrary to popular belief, he didn't just use Brahe's observations to select a geometric figure that fit the description. Yesterday's theologian directed his efforts to the discovery of a physical theory of the movement of "sisters living in an airless space", from which their orbits can be deduced. After a titanic research work, three laws of planetary motion appeared.
First Law
I. The orbits of the planets are ellipses with the Sun at one of the foci.
The law of planetary motion in the solar system established that the planets move in an ellipse. It appeared after eight years of calculations using a database compiled by Tycho Brahe based on observations of the planetary motion of the Star Mars. Johann called his work "New Astronomy".
So, according to Kepler's first Law, any ellipse has two geometric points called foci (focus in the singular). The total distance from the planet to each of the centers is always summed upthe same way, no matter where the planet is on its path. The importance of the discovery is that the assumption that the orbits are not perfect circles (as in the geocentric theory) brought people closer to a more accurate and clear understanding of the picture of the world.
Second Law
II. The line connecting the planet to the Sun (radius vector) covers equal areas in equal time intervals while the planet moves around the ellipse.
That is, in any period of time, for example, after 30 days, the planet overcomes the same area, no matter what period you choose. It moves faster as it approaches the Sun and slower as it moves away, but it moves at a constantly changing speed as it moves around its orbit. The most “nimble” movement is observed at perihelion (the point closest to the Sun) and the most “powerful” at aphelion (the point farthest from the Sun). So reasoned the one who discovered the laws of planetary motion.
Third Law
III. The square of the total period of orbital time (T) is proportional to the cube of the average distance from the planet to the Sun (R).
This principle is sometimes called the law of harmony. It compares the orbital time period and the orbital radius of the planets. The essence of Kepler's discovery is as follows: the ratio of the squares of the periods of motion and the cubes of the average distances from the Sun is the same for each planet.
To reiterate, Kepler's laws of planetary motion were based on long-term serious observations andprocessed mathematically. Displaying regularities, they did not reveal the conditionality of phenomena. Later, the famous discoverer of the law of universal gravitation, Newton, proved that the answer lay in the physical property of bodies to attract each other.
The shadow of my body is here
Despite his success, Kepler constantly suffered from financial troubles, lack of time for research, moving in search of places where his religious beliefs were tolerated. Several times he tried to get a teaching position in Tübingen, but was perceived as a traitor, a Protestant, and was rejected.
Johannes Kepler died on November 15, 1630 from an attack of acute fever. He was buried in a Protestant cemetery. In the epitaph, his legitimate son wrote: “I used the heavens to measure. Now I have to measure the shadows of the Earth. Although my soul is in heaven, the shadow of my body lies here.”
Yes, initially, in the spirit of medieval concepts, the scientist believed that the planets move because they have souls, this is living magic, and not just lumps of matter. Later, he realized that the scientific approach was more justified. Well, the priest and astronomer, who discovered the laws of planetary motion, honestly walked the path of insight. But let's admit it to ourselves: sometimes it seems that there is so much mysticism in the scientific Universe through and through!
