Twentieth-century milestones in the history of the Russian ephemeris service: Marking 100 years of the Calculation Institute and astronomical yearbook

This is the history of how the Russian ephemeris service for major and minor bodies of the solar system was created and developed to provide necessary data for the needs of astronomy, as well as ground-based, sea, and space navigation. The background of this presentation is various astronomical events described, as well as the life events of the institutions where the service was carried out.