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Reinbold, S. J.

Publications and source records attributed to Reinbold, S. J..

Navigation of the Mariner 10 spacecraft to Venus and Mercury

Orbit determination techniques used during the highly successful flight of Mariner 10 to Venus and Mercury are presented. Comparisons are made between different data sets, different sets of parameters, and between a conventional least squares batch filter and a sequential batch filter and smoother that was designed for this mission. The sequential filter was able to account for small spacecraft forces that the batch filter was unable to handle effectively, and hence, contributed greatly to the mission success. The sequential filter and smoother design is given as well as results for each phase of the mission.-

Christensen, C. S.↗

Demonstration of new data types for use in interplanetary navigation

Mariner 10 was the first mission which contained many elements of the advanced navigation system which will be used in the late 1970's and 1980's. Preliminary navigation demonstrated were conducted using S/X charged particle calibrations, simultaneous Doppler data, nearly simultaneous range data, and bright object/star imaging data. The results of these demonstrations are very encouraging and a navigation system based upon these data types should be an order of magnitude better than the current system.

Ondrasik, V. J.↗

Satellite orbit determination

A historic account of the activities of the Satellite OD Group during the MM'71 mission is given along with an assessment of the accuracy of the determined orbit of the Mariner 9 spacecraft. Preflight study results are reviewed, and the major error sources described. Tracking and data fitting strategy actually used in the real time operations is itemized, and Deep Space Network data available for orbit fitting during the mission and the auxiliary information used by the navigation team are described. A detailed orbit fitting history of the first four revolutions of the satellite orbit of Mariner 9 is presented, with emphasis on the convergence problems and the delivered solution for the first orbit trim maneuver. Also included are a solution accuracy summary, the history of the spacecraft orbit osculating elements, the results of verifying the radio solutions with TV imaging data, and a summary of the normal points generated for the relativity experiment.

Jordan, J. F.↗

Mars gravity field via the short data arcs

Short arc reduction of satellite Mars tracking data shows that: (1) There is one large gravity high covering the region of Nix Olympica and the three peaks to the east (about 110 deg longitude). It has an amplitude of 50 milligals at 2200-km altitude and implies a surface mass anomaly times greater than any on earth; (2) there are no large negative gravity anomalies comparable to the positive; and (3) the large 3000-km canyon seems to originate in a gravity high and end in a gravity low.

Sjogren, 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.↗

Determination of the relativistic time delay from the Mariner 9 superior conjunction data

The purpose of the analyses performed is to investigate the Mariner 9 superior conjunction range and Doppler data in order to determine the values for the relativity and solar corona time-delay parameters. This approach is complementary to the long arc normal point approach. The two methods of analysis differ insofar as: (1) This analysis investigates a much shorter arc of data. (2) This procedure deals directly with the Mariner 9 Doppler and range data; therefore it avoids the intermediate step involved in constructing pseudo-data. It is complementary to the reduction of the normal point data because it relies upon the generation of an Earth-Mars ephemeris, which is determined from the analysis of normal points as well as past optical and radar data.

Esposito, P. B.↗

Earth-moon mass ratio from Mariner 9 radio tracking data.

The phase-coherent range and Doppler tracking data obtained as a basis for the navigation of the Mariner 9 spacecraft from earth to Mars determine also the earth-moon mass ratio. As the earth revolves about the center of mass of the earth-moon system, a sinusoidal curve is impressed on the range and Doppler tracking data with a frequency equal to the sidereal mean motion of the moon. The mass ratio was determined from range and Doppler data obtained over a period of 15 weeks. The results from the Mariner Mars 1971 data are presented in a table together with previous results obtained in connection with other spacecraft.

Wong, S. K.↗

The determination of the satellite orbit of Mariner 9.

This paper presents a comprehensive analysis of the Mars orbital phase of the Mariner 9 trajectory as determined from Earth based radio data. Both the method and accuracy of the orbit determination process are reviewed. Analysis is presented to show the effects of Mars gravity model and node in the plane of the sky errors on the accuracy of orbit determination. In addition the long term evolution of the orbit from insertion to date is presented, and is decomposed into effects from the Mars gravity field, n-body perturbations, and solar radiation pressure. Since the orbit period is nearly commensurable with the Mars rotational period, the orbit experiences significant resonance perturbations. The primary perturbation is in-track with a maximum amplitude of 1000 km and a wavelength of 39 revolutions.

Born, G. H.↗