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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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Free-space einstein equations for concentrations of radiation held together by gravitational attraction, investigating gravity wave perturbations on background metric
Idealizations in cosmology with special theory of relativity - partitioned universe, microcosmic model, and similarity to Newtonian cosmology
Zero gravity satellite concept feasibility and control system design evaluation using air cushion vehicle
Passive damping method for aligning instantaneous spin, symmetry, and angular momentum axes of solid axisymmetric almost spherical satellite gyroscope
Adiabatic harmonic unitary transformations and relation between electron trapping energy and normal lattice modes associated with F center ground state
Static axisymmetric interior solution of Einstein field equations which matches smoothly to one of Weyl exterior solutions
Aeronomy experiment satellite polar orbit, control analysis, and control simulation
Relativistic corrections calculated for one way Doppler system used in calculating orbital velocity
Junction conditions across internal boundaries for Ricci rotation coefficients and Riemann tensor components in arbitrary reference tetrad frame
Relativistic theory of elastic and thermodynamic continuous media
Satellite attitude control using gyro-telescope structure driven by superconducting actuator
Equilibrium configurations of self-gravitating particles systems by self consistent fields method
Einstein field equations solutions generated via static spherically symmetric mass and charge distributions
Gravitational relativistic theory tests using tracking data from interplanetary spacecraft, orbiters and landers
The results from ground-based experimental testing are presented. Prospects for improving these experiments are discussed. Radar echo time delays, perihelion advance and solar oblateness, time variation of the gravitational constant, and radio wave deflection are considered. Ground-based and spacecraft techniques are compared on an accuracy vs. cost basis.
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A computer program is described which can be used to study the feasibility of conducting relativity experiments on a wide range of hypothetical space missions, and a few applications are presented for solar probes which approach the Sun within 0.25 to 0.35 AU. It is assumed that radio ranging data are available from these spacecraft, and that accuracies on the order of 15 meters can be achieved. This is compatible with current accuracies of ranging to Mariner spacecraft. At this level of accuracy, the range data are sensitive to a number of effects, and for this reason it has been necessary to include a total of up to 23 parameters in the feasibility studies, even though there are only two parameters of real interest in the relativity experiments.
Performance tests of gyroscope operations and gyroscope readout equipment are discussed. The gyroscope was tested for 400 hours at liquid helium temperatures with spin speeds up to 30 Hz. Readout by observing trapped magnetic flux in the spinning rotor with a sensitive magnetometer was accomplished. Application of the gyroscope to space probes and shuttle vehicles.