A concise illustrated overview of astronautics for a general audience, published as n° 75 in Hachette's "Encyclopédie par l'image" series. Across four illustrated chapters, Pierre Rousseau traces the origins of the space dream (from Fontenelle to Tsiolkovsky), the satellite revolution (Sputnik, Explorer, Telstar), the human conquest of low Earth orbit (Mercury, Vostok, Voskhod), and the prospects for interplanetary exploration toward the Moon, Venus, and Mars. The volume covers events up to Voskhod (October 1964) and includes a table of notable satellites from 1957 to 1964.