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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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Determination of lunar electrical conductivity profile from joint power spectral density analysis of data from Apollo 12 and Explorer 35 magnetometer data
Quasars spectrophotometry data, obtaining physical conditions, abundances and electron temperature
Galactic cosmic ray solar modulation with 20 year periodicity, suggesting nearby galactic magnetic field direction
Magnetopause electric field accounting for ATS 5 energetic proton and electron flux measurements, comparing to various models
Plasma sheet convection velocities from electron flux measurements at synchronous altitude, noting flux increase time dependence on energy
Fossil lunar magnetism observations, using magnetometer data from orbiter Explorer 35
Radar based values of neutral night exospheric temperature, discussing dominant effect of annual variation
Lunar electrical conductivity profile from joint power spectral density analysis of Apollo 12 and Explorer 35 magnetometer data
Electromagnetic induction in the moon driven by fluctuations of the interplanetary magnetic field is used to determine the lunar bulk electrical conductivity. The present data clearly show the north-south and east-west transfer function difference as well as high frequency rollover. The difference is shown to be compatible over the mid-frequency range with a noise source associated with the compression of the local remanent field by solar wind dynamic pressure fluctuations. Models for two, three, and four layer; current layer, double current layer, and core plus current layer moons are generated by inversion of the data using a theory which incorporates higher order multipoles. Core radii conductivities generally are in the range 1200 to 1300 km and 0.001 to 0.003 mhos/m; and for the conducting shell 1500 to 1700 km with 0.0001 to 0.0007 mhos/m with an outer layer taken as nonconducting. Core temperature based on available olivine data is 700 to 1000 C.
Medium resolution radiometer measurements on Nimbus 2 and 3 and relatively high resolution measurements on Nimbus 4 have been made in 6.4 to 6.9 and 20 to 23 microns water vapor absorption regions where the weighed means in the observed radiation occur in the troposphere near the 400 and 600 mbar levels, respectively. An example of the imagery obtained from the Nimbus 4 temperature-humidity infrared radiometer (THIR) is shown. This example demonstrates clearly that there is a distinct pattern difference between the 6.7 microns observations coming from the midtroposphere and the more common 11.5 microns atmospheric window observations showing the emitted radiation associated with opaque surfaces such as the ground or optically thick clouds.
Analysis of lunar particle size distribution data indicates that the surface material is composed of two populations. One population is caused by comminution from the impact of the larger-sized meteorites, while the other population is caused by the melting of fine material by the impact of smaller-sized meteorites. The results are referred to Mars, and it is shown that the Martian atmosphere would vaporize the smaller incoming meteorites and retard the incoming meteorites of intermediate and large size, causing comminution and stirring of the particulate layer. The combination of comminution and stirring would result in fine material being sorted out by the prevailing circulation of the Martian atmosphere and the material being transported to regions where it could be deposited. As a result, the Martian surface in regions of prevailing upward circulation is probably covered by either a rubble layer or by desert pavement; regions of prevailing downward circulation are probably covered by sand dunes.
Discussion of the modification of the DENDRAL computer program to extend the program to cyclic structures which exceed numerically the linear molecules of a given composition. IR, NMR and mass spectroscopy is used to develop a method for identification of each of the 27 possible ketones (exclusive of 5 cyclopropanones) of composition C6H10O.
Further simultaneous two-color photoelectric photometry of Ganymede was carried out at blue (4500 A) and yellow (5790 A) wavelengths during its eclipse by Jupiter on Mar. 10, 1971. In both colors, the shape of the ingress light curve was again reliably determined for extinctions up to 9 mag. Neither curve showed any evidence of a refraction tail. The observations have been interpreted in terms of the local optical transmission properties of the Jovian atmosphere. At gas number densities of about 5 x 10 to the 18th power per cu cm the maximum photon scattering mean free path at visual wavelengths was 47 km atm. Evidence indicates that neither a simple reflecting-layer model or a semiinfinite homogeneous scattering model provides an adequate physical description of the atmosphere.
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The mathematical inversion of light-scattering observations to obtain the atmospheric ozone profile is discussed in terms of the filtering properties of the physical and mathematical processes for different spatial scales. Within this context, it is shown that the physical process of scattering acts as a low pass filter; which transfers large-scale profile information efficiently to radiance observations but very strongly attenuates small- or fine-scale profile information. To avoid domination of the mathematical inversion by the random error of radiance measurements, an equivalent spatial-scale filtering in the inversion procedure is essential. The available evidence suggests that mathematical inversion to obtain the low level ozone profile below 25 to 30 km is either inferior to or no better than the statistical estimation of the profile using total ozone as predictor. However, inversion profiles for high level ozone above 25 to 30 km appear to have moderately good accuracy.
Spectral signatures of phytoplankton and other obscuring effects are considered in order to determine how to best use satellite data. The results of this study were then used to analyze the spectral data obtained from the ERTS-1 multispectral scanner (MSS). The analyzed satellite data were finally compared with surface ship measurements of chlorophyll concentration. It was found that the effects of water turbidity on the multispectral imagery can be discriminated by rationing the two shortest wavelength channels so that the effect of phytoplankton is enhanced.
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Explore the source record for details and available documents.