The great astronomical discoveries of Nicolaus Copernicus, Tycho Brahe, Johannes Kepler, and Galileo Galilei marked the beginning of a new scientific era, stimulating the development of the exact sciences. Astronomy had the great honor of laying the foundations of natural science: in particular, the creation of a model of the planetary system led to the emergence of mathematical analysis. From this brochure, the reader will learn about many fantastic achievements in astronomy made in recent decades. The text of the brochure is an addition by the author to the recording of a lecture he gave for schoolchildren in grades 9-11 on November 11, 2000 at the Small Mechanics and Mathematics Department of Moscow State University. The brochure is intended for a wide range of readers: high school students, junior students, teachers...