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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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At least 217 records · Page 12
All sourcesNASA NTRSDOE OSTI
NASA NTRS1972

On the determination of the long period tidal perturbations in the elements of artificial earth satellites

The magnitude of the tidal effects depends upon the elastic properties of the earth as described by Love numbers. The Love numbers appear as the coefficients in the expansion of the exterior tidal potential in terms of spherical harmonics (in Maxwellian form). A single averaging process was performed only along the parallels of latitude. This process preserves additional long period tidal effects (with periods of a few days or more). It also eliminates the short period effects with periods of one day or less.

Musen, P.↗
NASA NTRS1972

Theory of an experiment in an orbiting space laboratory to determine the gravitational constant.

An experiment is discussed for determining the gravitational constant with the aid of an isolated system consisting of an artificial satellite moving around an artificial planet. The experiment is to be conducted in a spherical laboratory traveling in an orbit around the earth. Difficulties due to the gravity-gradient term are considered, and the three-tunnel method proposed by Wilk (1969) is examined. The rotation of the sphere is discussed together with aspects of the reference systems used, the equations of motion of the spacecraft and of the test objects, the field from the earth's gravity gradient at the test object, higher harmonic terms in the gravity gradient force, gravitational effects of the spacecraft itself, and a computer simulation.

Vinti, J. P.↗
NASA NTRS1972

Pole position studied with artificial earth satellites.

Long-arc orbit computation of highest accuracy can provide pole positions. Optical Baker-Nunn and laser range observations of several satellites are combined. The accuracy of the pole position is comparable to that of the mean satellite-tracking station coordinates (plus or minus 5 m) when sufficient tracking data are available. Exploitation of the technique requires more accurate tracking data.

Gaposchkin, E. M.↗
NASA NTRS1975

A study of cosmic rays on the artificial moon satellites Luna-11 and Luna-12

In the period from the end of August 1966 to January 1967 the primary cosmic radiation fluxes beyond the terrestrial magnetosphere were measured by means of the equipment mounted on the satellites Luna-11 and Luna-12. The altitude dependence of cosmic rays near the lunar surface as well as the intensity of protons and electrons of solar origin in the moon's vicinity were determined. The correlation of proton intensity with the parameters characterizing the solar and geomagnetic activities and the specific features of the angular distribution of the proton flux as revealed during measurements are given. Data on electron fluxes studied on September 1 and 8, 1966, when short term increases in the electron intensity were observed are included.

Grigorov, N. L.↗
NASA NTRS1975

The study of cosmic rays on the proton artificial earth satellite

Investigations were carried out with the space stations of the Proton series to study the physics of cosmic rays. The SEZ-13 device for the search of particles with a fractional electrical charge and the SEZ-11 device for the measurement of high energy electrons were mounted on the Proton-3 satellite. The mode of action of the SEZ-11 device differed from that of the SEZ-12 device used in the Proton-1 and Proton-2 satellites for similar purposes. Some of the results that were obtained are presented.

Grigorov, N. L.↗
NASA NTRS1975

Some procedures for computerized electronic data processing of absorption measurements from artificial earth satellites

The processing of data obtained from solar absorption radiation measurements is discussed. The position of the satellite was obtained by numerical integration of the differential equations of motion using initial conditions. The position of the sun was calculated as a function of time, and the tangential elevation was determined approximately from the positions of the satellite and the sun. The coefficients of an approximation formula and of a data smoothing process were determined, and the inversion of an Abel integral equation is solved analytically.

Trinkkeller, B.↗