The book is devoted to modern problems of astronomy: from the study of the moon and planets to the search for gravitational waves, dark matter and dark energy. Scientists of the State Astronomical Institute. P.K.Sternberg (Moscow State University) talk about what the most important events took place in astronomy at the turn of the new millennium and what unresolved problems researchers are now working on. The conditional historical milestone - the beginning of the new millennium - was marked by several important discoveries in the study of the Universe. Therefore, recent years can without exaggeration be called the great decade of astronomy, perhaps the beginning of its new "golden age." Extensive reference material is included in the "Appendix." The book is addressed to high school students, students and teachers, as well as everyone interested in the problems of modern natural science.