Astronomical observations of recent years strongly suggest that our galaxy, the Milky Way, is heavily populated by antimatter. In their properties, antiparticles are the opposite of our matter, common elementary particles. The discovery of antimatter is considered to be one of the most important events in physics in the 20th century. But what do we know about antimatter today? We asked this question to Alexander Dolgov, Dr. Sc. (Phys.-Math.), Professor, Director of the Novosibirsk State University Interdisciplinary Center of Elementary Particle Physics and Astrophysics.