The idea of sculpture with no visible contact with the earth, hovering in space without the usual vertical and horizontal orientation, arose in contemporary art practice during the postwar decades, amid the Cod War race for space. In Milan, Paris, Düsselforf and New York, an array of floating art projects were attempted both inside -and outside- the art gallery. These artistic experiments offered a counterpoint to the first satellites and manned spacecraft, using simple technologies including magnets and balloons to address complex aesthetic issues raised by the outer-space environment and, in particular, the zero-gravity field. By the late 1960s, free-floating "aerial" and "pneumatic" art had become an international trend, reflecting a new conception of art's meaning during a time of cultural and technological change.