When studying the starry sky, they use star maps compiled in certain cartographic projections, therefore, when comparing the starry sky with a map, it is necessary to take into account image distortions in these projections. All stars, depending on their apparent brightness, are divided into classes called stellar magnitudes.

In our reference book on astronomy, almost all sections of modern astronomy are presented: a historical overview, the basics of practical astronomy, the laws of motion of celestial bodies, the structure of the solar system, methods of astronomical research, basic information about the sun, stars, planets, galaxies and the universe as a whole. To work with the textbook, knowledge of the basic sections of mathematics, physics and chemistry is required within the scope of a high school course.