Everyman's Doppler Satellite Navigation System

This paper describes a system of navigation by measurement of the Doppler shift in the radio transmissions from a near-Earth satellite, and simple equipment for making the measurements. It also shows that the current information which is needed by the navigator can be reduced to a number containing six decimal digits. Finally, it shows that the computations needed for the navigator to obtain a fix can be performed witlh the aid of tables that can be prepared at least 18 months in advance. Using these tables and a simple slide rule, but no other computational aids, a fix accurate to about 500 meters can be obtained in about 10 minutes. More accuracy can be obtained at the expense of time, or time can be saved at the expense of accuracy.     

Changing structure of the Soviet space programme

Political and economic changes in the USSR are having a dramatic impact on the nature and direction of the Soviet space programme. This article describes the main elements of what can now be seen as a sprawling and fractured bureaucracy. Some voices within the USSR are calling for the creation of some kind of national space agency, but the forces making for further fragmentation seem stronger. Whatever the eventual outcome, new opportunities for international commercial contact are likely to arise.     

United States space policy and international partnership

Has the current US space policy improved the USA's overall strategic position? Does it affect favorably international partnerships? These questions are examined in terms of security, political economy, and influence. In today's context, where there are more space players, more options, more potential for unintended consequences, and higher stakes, unilateral action is more limited in its effectiveness than in earlier times. Surveying current US space policy, it is not clear that data-driven, analytically based decisions are being made to affect positively national independence, innovation, market creation, and international perceptions of the USA as a trustworthy partner. More promising are the steps taken to bolster a predictable space operational environment and economic competitiveness. Ultimately, in order to achieve American excellence and leadership, a ‘closed loop’ on the policy system is needed, to gauge regularly and systematically whether the US is achieving the desired national outcomes.