The book of Y.I. Perelman introduces the reader to modern astronomy and its remarkable scientific achievements, tells in a fascinating form about the most important phenomena of the starry sky, about the laws of motion of the Earth, the Sun, the Moon and the starworld as a whole. The author shows many seemingly familiar and ordinary phenomena from a completely new and unexpected side and reveals their real meaning. The task of the book is to expand before the reader a wide picture of the world space and the amazing phenomena taking place in it, and arouse interest in one of the most fascinating sciences, the science of the starry sky.