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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Lunar gravitational field effect on sun-earth exterior libration point location, examining placement on line passing through sun and earth-moon barycenter
The Integrated Life Support System was conceived to study the problems of integrating regenerative equipment designed to operate in a negligible gravitational field. It is the first to fully integrate the three major contributors to atmospheric contamination: man, machine, and materials.
Difference indicating circuit used in conjunction with device measuring gravitational fields
Random distribution of radial motions in central gravitational field, Newtonian mechanics, and comet orbits about sun
Tesseral harmonics of Explorer 34 satellite orbit perturbation in time of perigee passage due to third harmonic of earth gravitational field
Lunar topographic, geologic, magnetic field, gravitation, and atmospheric data from Apollo 14 experiments and photography
Analysis of Lunar Orbiter data and interpretation of lunar gravitational field
Lunar satellite motion semianalytic solution, considering perturbative effects due to gravitational fields, solar radiation pressure and libration
General relativistic time delay of electromagnetic radiation propagation due to solar gravitational field measured from Mariner 6 and 7 range and Doppler data
GEOS-C geodetic satellite purpose and equipment, discussing earth gravitational field study, radar altimeter possibility and tracking systems usefulness
Plants behavioral reactions to continuous gravitational field directional reorientation by clinostat, discussing gravity compensation effects on tropism and forces required for geotropic response
Statistical space velocity distributions, gravitation field strength and vertex deviation for nearby young stars, using density wave theory of galactic spirals
High velocity H alpha ejections in association with important solar flare on 12 March 1969, suggesting mass motions control by gravitational field
The Surveyor 3 television camera shroud and polished aluminum tube, retrieved as a result of the Apollo 12 mission after 2-1/2 years on the lunar surface, were examined at the NASA Manned Spacecraft Center for evidence of meteoroid impact. The results of this examination were compared with other estimates of the meteoroid flux in the lunar vicinity and are shown to be in good agreement with the Lunar Orbiter penetration rates. In addition, the relationship between a derived lunar surface meteoroid cumulative-flux model and the comparable near-earth model is discussed in the light of theoretical predictions. It is shown that the effect of the gravitational field of the earth on the near-earth environment was greater than previously predicted. The implication is that the average meteoroid velocity relative to the earth is probably 17 km/s. The many low velocity impacts on the Surveyor 3 camera and tube are shown to be of lunar surface origin and to be primarily the result of rocket exhaust interaction.
Satellite altitude determination uncertainties are discussed from the standpoint of the GEOS-C satellite. GEOS-C will be tracked by a number of the conventional satellite tracking systems, as well as by two advanced systems; a satellite-to-satellite tracking system and lasers capable of decimeter accuracies which are being developed in connection with the Goddard Earth and Ocean Dynamics Applications program. The discussion is organized in terms of a specific type of GEOS-C orbit which would satisfy a number of scientific objectives including the study of the gravitational field by means of both the altimeter and the satellite-to-satellite tracking system, studies of tides, and the Gulf Stream meanders.
The experiment which derives data from three lunar-orbiting objects, the command-service module (CSM), the lunar module (LM), and the subsatellite in the S-band is described. Each provides detailed information on the near-side lunar gravitational field. The primary emphasis is on the low-altitude (20 km) CSM data. The LM data cover a very short time span and are somewhat redundant with the CSM data. The resolution of the high-altitude (100 km) CSM data is not as great as that of the low altitude data. The low-altitude CSM and LM data coverage and the complementary coverage obtained during the Apollo 14 mission are presented. The experiment uses the same technique of gravity determination employed on the Lunar Orbiter, in the data of which the large anomalies called mascons were first observed. The data consist of variations in the spacecraft speed as measured by the Earth-based radio tracking system.
The height of the GEOS-C spacecraft was utilized as measured by the onboard radar altimeter, for an improved determination of the earth's gravitational field and for the determination of the variation of the physical surface of the oceans. Two tracking system approaches to accurately determine the spacecraft height (orbit) are described and their results stated. These are satellite-to-satellite tracking (SST) and ground laser tracking (GLT). Height variations can be observed in the dm-regions using SST and in the m-region using present GLT.
Adaptation of otolith organ activity was investigated by monitoring the ocular counterrolling response of four normal individuals and three persons with severe bilateral loss of labyrinthine function. Several eye photographs were recorded every 30 minutes during a period of 8 hours in which the subject was held in a lateral tilt (60 deg) position. The recorded eye roll position varied to an expected small extent within each test session; this variation about a given mean roll position was similar among the test sessions for all subjects. The mean roll position, on the other hand, changed from session to session in substantial amounts, but these changes appeared to be random with respect to time and among subjects. Furthermore, the intersessional variation in the mean torsional eye position of the normal subjects was equivalent to that of the labyrinthine-defective subjects who displayed little or no counterrolling. These results suggest that the human counterrolling response is maintained either by essentially nonadapting macular receptors or by extremely fine movements of the head in the gravitational field, such as may have been allowed by the biteboard/headrest restraint system used in this study, which served as an everchanging accelerative stimulus.