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The experience on the first backscatter lidar operating in space (LITE, USA, 1994; BALKAN, Russia, 1995 - 1997; ALISSA, Russia-France, 1996 - present time) is analyzed to provide a basis for guiding the development of new orbital lidars. Considering the status of development of laser sensing methods harnessing elastic scattering and needs for obtaining information on global distributions of atmospheric aerosols and cloudiness in real time, approaches to the conversion of lidars of this class from the testing regime of operation to the monitoring one are discussed. Within the framework of this approach the design features of lidar intended for accommodation on small space stations most suitable for monitoring are investigated. For such a lidar a deploying segmented mirror has been suggested which does not provide a narrow directional pattern due to the conditions of its transport to the orbit. Multiple scattering by atmospheric aerosols, which is responsible for principal background noise component of lidar return signals, has been investigated for lidars with large field-of-view angles. It is demonstrated that the multiple scattering background reaches 30% and more for a field-of-view angle of 20 mrad even under background conditions. The possibilities for consideration of this background contribution are discussed. Spaceborne lidar sensing methods, which have been developed insufficiently, necessitate the use and development of universal lidars that envisage the attention of the crew, that is, lidars for manned spacecrafts and space stations. The universal spaceborne lidar BALKAN-E, intended for testing of the methodology of ozone and aerosol sensing based on the differential absorption and scattering of laser radiation, is described. Similar lidars placed on stations with other scientific instruments will optimize a set of means for an integrated study of the Earth owing to mutually complementary measurements.
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