July 9: Johannes Kepler publishes the book

His first scientific work known and appreciated is the book "Mysterium Cosmographicum" (Cosmic Mystery).

He is known for the laws of motion and the orbits of planets , he also invented the reflective telescope (Kepler telescope).

His research and inventions must be evaluated until later, and at that time people still confuse astronomy and astrology. His first scientific work known and appreciated is the book " Mysterium Cosmographicum " (Cosmic Mystery).

Johannes Kepler is known for the laws of motion and orbit of planets.

On July 9, 1595, he published this book and first published the geometry of the universe , also known as the Platon model . However, at that time, Kepler only calculated the planets' orbital shapes according to regular polygons.

Basically, he built a cosmic model with three-dimensional polyhedra shapes . In it, he uses polygons with sizes and shapes based on his calculations. Then, insert them together into a three-dimensional polyhedron, simulating the structure of the solar system.

After completing your model corresponds to 6 planets known at that time as Mercury, Venus, Earth, Mars, Jupiter and Saturn. Kepler realized that the polygons he created could be either inline or outward of a circle or ellipse.

Platon polyhedron universe model.

From there, he began to think that the planets' orbits could be arc paths. Next, he tried to calculate the connections between planets and their orbits. And to explain why planets have different orbits. However, his calculations were not really accurate at the time.

Despite this book Mysterium Cosmographicum laid the first foundation for astronomy in understanding the orbit of planets in the solar system. In addition to this work, Kepler also contributed many other researches on astronomy.

In particular, the study of the correlation between the position of planets and weather phenomena must be mentioned. Kepler has found that it is Earth's position relative to the Sun that determines weather conditions like spring, summer, autumn and winter. He also has many studies on the Moon and the movement of satellites around stars.

In 2009, NASA used Delta II boosters to bring the Kepler telescope into space. This is a historical mission, not merely a scientific mission, to help us answer the question: " Is the earth the only planet with life? ". The name of this telescope is named after him to commemorate his invention of planets orbiting stars' orbits.