Geodetic Precision in One Perspective

Aero-space vehicle guidance systems with accuracies superior to the capabilities of conventional geodetic measuring techniques, are generating requirements for geodetic positioning information. In addition, as measuring techniques are developed that approach the desired results, the improvement in precision of measurement becomes limited by uncertainties in knowledge of environmental factors affecting measurement accuracy, i.e., atmospheric refraction. Geodetic experiments with specially instrumented satellites have already returned several types of significant, useful data, that compare favorably with existing geodetic information in positional accuracy and offer advantages in range of measurement. Such experimentation shows that artificial satellites can contribute to improved geodetic precision by extending range and areal coverage of measurements, and by offering methods for improving knowledge of the fundamental constants used in geodetic measurements.