This volume devoted to astronomical and atmospheric refraction is singular in several ways.First, by the apparent simplicity of the phenomenon discussed here, the refraction of light, taught in high schools with the famous Snell-Descartes formula found at the beginning of the xvii th century, and whose study, going back to the x th century with Ibn Sahl, did not cease to fascinate the astronomers in front of the difficulty of observing the stars after the travel of their light in the Earth's atmosphere.Then, by the concern of many of the present authors to follow the historical evolution of the problem in referring explicitly to some of the most important original articles that have marked this research until the advent of satellites.Finally, by the number and the content of articles written in French in order to allow easy access to teachers, in particular of the first cycle of higher education, and to invite them to show to their students the genesis of a scientific approach of almost four centuries, carried out between mathematics, astronomy and physics.This volume is an educational issue of history of science, an exemplary illustration of the story of great scientific adventures, which we hope will be the first of its kind but not the unique one. Perceiving the progress of science in its historical dimension is an essential approach to practice