‘Zero-gravity’ physics—the spacelab project

Abstract

Abstract The removal of the constraint of gravity opens the door to the study of a wide range of effects that are difficult to observe in a terrestrial laboratory. This applies particularly to fluids in which, for example, convection effects due to density gradients and the segregation of solid particles, immiscible liquid droplets or bubbles are no longer present. The study of such phenomena is not limited to academic interest but is of great importance to modern technology which can benefit in two ways. Firstly it may be possible to produce new materials, or improved materials which cannot be made to high quality on Earth because of the effects of gravity, such as better vaccines through improved electrophoretic separation, large single crystals of semiconductors to high perfection and novel immiscible alloys or composite materials. Secondly, experiments under reduced gravity will help improve the design of Earth-based processes by providing data unobtainable on Earth, such as the thermal conductivity of highly reactive liquids in the absence of convection. Many of these ideas have been proved by experiments performed on Skylab, but the cooperative venture between NASA and the European Space Agency to design, build and fly a space laboratory called ‘Spacelab’ will enable scientists to obtain further access to space to evaluate and develop the potential of processing in a good approximation to zero gravity.