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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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NASA NTRS1971

Correlations among the parameters of the spherical model for eclipsing binaries

Correlation coefficients were computed to investigate the parameters for describing the spherical model of an eclipsing binary system. Regions in parameter hyperspace were identified where strong correlations exist and, by implication, the solution determinacy is low. The results are presented in tabular form for a large number of system configurations.

Sobieski, S.↗
NASA NTRS1972

The ionosphere above Alma Ata during a solar eclipse

The eclipse effect was manifested during the second phase: the ionization of the F1- and F2-layers decreased and the minimum effective heights of E and F2 increased due to recombination processes. The manner in which electron density is distributed over the levels was ascertained from analysis of N(t) curves.

Rudina, M. P.↗
NASA NTRS1972

Photometric studies of Saturn's ring and eclipses of the Galilean satellites

Reliable data defining the photometric function of the Saturn ring system at visual wavelengths are interpreted in terms of a simple scattering model. To facilitate the analysis, new photographic photometry of the ring has been carried out and homogeneous measurements of the mean surface brightness are presented. The ring model adopted is a plane parallel slab of isotropically scattering particles; the single scattering albedo and the perpendicular optical thickness are both arbitrary. Results indicate that primary scattering is inadequate to describe the photometric properties of the ring: multiple scattering predominates for all angles of tilt with respect to the Sun and earth. In addition, the scattering phase function of the individual particles is significantly anisotropic: they scatter preferentially towards the sun. Photoelectric photometry of Ganymede during its eclipse by Jupiter indicate that neither a simple reflecting-layer model nor a semi-infinite homogeneous scattering model provides an adequate physical description of the Jupiter atmosphere.

Brunk, W. E.↗
NASA NTRS1971

L-alpha measurements during the solar eclipse of 12 November 1966.

Rocket measurements of the solar L-alpha (1216 A) flux during various phases of the total eclipse on Nov. 12, 1966 confirm that the radiation emanates from the chromosphere. A significant difference between two portions of the photosphere limb is attributed to enhanced emission in the region of a Ca K plage. The average size of the L-alpha disk is found to be approximately 4000 km above the photosphere, and a brightening is observed at the limb.

Weeks, L. H.↗
NASA NTRS1972

Synthesis of data obtained at Jicamarca, Peru, during the September 11, 1969, eclipse.

Results of continuous measurements of electron temperatures, electron concentrations, and vertical plasma drift made at Jicamarca during the Sept. 11, 1969, solar eclipse and of control measurements made on Sept. 13, 1969. Synthesis of the observed electron concentrations was made, using a model that solved the time-dependent electron-ion continuity equations. Ions O(-), NO(+), O2(+), and N2(+) were treated. Physical and chemical processes pertinent to the F region were considered in a realistic way. At noon, 300 km above Jicamarca, the values q = 290 per cu cm per sec for the O(+) production rate, beta = 1.94 x 0.0001 per sec for the loss coefficient, and H = 59 km for the atomic oxygen scale height were obtained. All large-scale features observed in the F2 region were synthesized by the model. This synthesis was not sensitive to a simultaneous 30% reduction of q and beta.

Sterling, D. L.↗
NASA NTRS1972

Rocket observations of solar X-rays during the eclipse of 7 March 1970.

Measurement of the absorption profiles and residual fluxes of three bands of solar X-rays before and during the eclipse of Mar. 7, 1970. In the bands 2 to 8 A, 8 to 20 A, and 44 to 60 A the residual flux in totality is found to be respectively 5, 7, and 16% of the flux from the uneclipsed sun. It is shown that the radiation maintaining the E-layer varies in proportion to the 44- to 60-A flux. In the D-layer, ionization by the residual flux of 2 to 8 A is less important in totality than is ionization of nitric oxide by Lyman-alpha.

Accardo, C. A.↗