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Astrodynamics. Volume 1 - Orbit determination, space navigation, celestial mechanics.

Essential navigational, physical, and mathematical problems of space exploration are covered. The introductory chapters dealing with conic sections, orientation, and the integration of the two-body problem are followed by an introduction to orbit determination and design. Systems of units and constants, as well as ephemerides, representations, reference systems, and data are then dealt with. A detailed attention is given to rendezvous problems and to differential processes in observational orbit correction, and in rendezvous or guidance correction. Finally, the Laplacian methods for determining preliminary orbits, and the orbit methods of Lagrange, Gauss, and Gibbs are reviewed.

Herrick, S.

Mariner 9 celestial mechanics experiment - Gravity field and pole direction of Mars.

Analysis of the Mariner 9 radio-tracking data shows that the Martian gravity field is rougher than that of earth or the moon, and that the accepted direction of the Mars rotation axis is in error by about 0.5 deg. Contours of equivalent surface heights deduced from a sixth-degree solution for the Martian gravity field are presented. These contours represent the deviations from sphericity of a uniformly dense body with an external potential which is given by the first sixth-degree solution. In addition to Doppler observations, ranging or group-delay measurements have been made regularly since orbit insertion.

Lorell, J.

The Mariner 9 celestial mechanics experiment

There are two main objectives in the Mars gravity field analysis. The first is to generate a picture of the gravity field which can be used in conjunction with other types of data to elucidate the interior, surface structure, and history of Mars. The second is to aid the orbit determination aspect of the relativity experiment. In an effort to extract from the data a Mars gravity model of reasonable fidelity, various spherical harmonic models have been made. A parallel effort using a surface mass representation involves the differentiation of Doppler residuals for acceleration contours.

Lorell, J.

Data acquisition and editing for the celestial mechanics experiment

A radio tracking subsystem is reported in which the critical elements are the frequency standard and its distribution subsystem, as they ultimately limit the accuracy of both range and Doppler measurements. A rubidium vapor standard serves as the primary reference. After frequency multiplication to S-band and additional amplification, the carrier is transmitted to the spacecraft where a phase-locked receiver-transmitter system filters the signal, introduces a slight frequency shift, and retransmits it to the ground. Doppler is measured by comparing the received frequency with that being transmitted.

Martin, W. L.

Determination of normal points for the relativity test of the celestial mechanics experiment

The relativity test is based on Mariner 9 tracking data acquired by the Deep Space Network. These data consist of two types of measurements: (1) two-way frequency difference (Doppler) measurements that are proportional to the tracking station-spacecraft range rate, and (2) signal round trip time-delay measurements that are proportional to the station-spacecraft range. A data compression scheme has been employed to alleviate accuracy and cost difficulties by (1) using the Doppler data to solve for the spacecraft orbit and to relate spacecraft position to the center of mass of Mars; and (2) combining this result with the station-spacecraft range measurements to obtain measurements of the Earth-Mars distance, called normal points, that contain all of the information pertinent to a detailed knowledge of the Earth-Mars motion.

Jordan, J. F.

Celestial mechanics experiment

The efforts and accomplishments of the CME Team are summarized. The objectives and experiment status, gravity field of Mars, test of general relativity, and the generation of normal points are discussed.

Lorell, J.

A study to determine the usefulness of interval analysis in solving problems in celestial mechanics

This investigation was undertaken to determine the usefulness of interval analysis to numerical integration and matrix inversion techniques and to combine these results to determine the value of interval analysis in bounding computational errors in the two-body problem. Conclusions were that interval analysis may be worthwhile in certain small scale isolated problems, but its usefulness in any large scale problem is doubtful.

Walling, D.

Pioneer Saturn celestial mechanics experiment

The paper investigates a continuous round-trip radio link at S band (2.2 GHz) that was maintained during the Pioneer Saturn encounter between stations of the Deep Space Network and the spacecraft. From an analysis of the Doppler shift in the radio carrier frequency, a number of gravitational effects on the trajectory were determined. Gravitational moments for Saturn were found from a preliminary analysis, as well as mass values for the Saturn satellites Rhea, Iapetus, and Titan. It was determined that the densities of all three satellites are low and consistent with the compositions of ices. Theoretical calculations for the Saturn interior are described which use the latest observational data, including Pioneer Saturn and state-of-the-art physics for the internal composition.

Anderson, J. D.

Essays on the History of Rocketry and Astronautics: Proceedings of the Third through the Sixth History Symposia of the International Academy of Astronautics, Volume 1

This two volume publication presents the proceedings of the third through sixth history symposia of the International Academy of Astronautics. Thirty-nine papers are divided into four categories: (1) Early Solid Propellant Rocketry; (2) Rocketry and Astronautics: Concepts, Theory, and Analyses after 1880; (3) The Development of Liquid and Solid Propellant Rockets from 1880 to 1945; and (4) Rocketry and Astronautics after 1945. Categories 1 and 2 will be found in volume 1 and the remainder in volume 2. Among other diciplines, Rocketry and Astronautics encompasses the physical and engineering sciences including fluid mechanics, thermodynamics, vibration theory, structural mechanics, and celestial mechanics. Papers presented in these two volumes range from those of empirical experimenters who used the time-honored cut and try methods to scientists wielding theoretical principles. The work traces the coupling of the physical and engineering sciences, industrial advances, and state support that produced the awesome progress in rocketry and astronautics for the most part within living memory. The proceedings of the four symposia present in these two volumes contain information on the work of leading investigators and their associates carried out in the first two-thirds of the twentieth century.

R Cargill Hall

Advanced algorithm for orbit computation

Computational and analytical techniques which simplify the solution of complex problems in orbit mechanics, Astrodynamics and Celestial Mechanics were developed. The major tool of the simplification is the substitution of transformations in place of numerical or analytical integrations. In this way the rather complicated equations of orbit mechanics might sometimes be reduced to linear equations representing harmonic oscillators with constant coefficients.

Szenbehely, V.