The fifth volume in the Histoire universelle des explorations series, this book by Albert Ducrocq surveys the exploration of the solar system as it stood in 1975. Its first part traces the study of the Moon, from myth and telescopic selenography to the Apollo and Luna missions, complete with glossaries of landing sites and lunar nomenclature. The second part ranges across the other worlds: Mars (from Schiaparelli's canals to the Mariner and Mars probes), Venus, Mercury, the giant planets reached by Pioneer 10, and the question of other planetary systems. The work is richly illustrated with photographs and maps.