Theorems concerning the allowed cone of cosmic radiation
Theorems concering cosmic ray shadow cone extended to include main cone at higher latitudes
COSMIC RAY↗
SEARCH · Engineering Papers
Results for “shadows”
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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MSFC computer programs utilized in the thermal design and analysis of satellites
Three IBM 7094 computer. program used in the thermal design of spacecraft will be discussed. The first program is one used for integrating spectral reflectance or emittance. The second program calculates the percent time a satellite spends in the earth's shadow during a revolution about the earth. And the third program is called our General Space Thermal Program and is used to calculate satellite temperatures throughout a revolution about the earth.
THERMAL ENVIRONMENT↗
Earth as an occulting disk for study of solar EUV emission heights.
Source distributions of UV and X-ray emission in corona and chromosphere determined from flight of spacecraft-borne instruments into Earth shadow
OCCULTATION↗
Effects of cryodeposits on spacecraft thermal control systems.
Cryodeposits effects on spacecraft thermal control systems with respect to surface radiative properties and to shadow shield surfaces
SPACECRAFT ENVIRONMENT↗
The Effect of Planetary Albedo on Solar Orientation of Spacecraft
The analytical expression for the solar orientation error caused by planetary albedo is derived. A typical solar sensor output characteristic is assumed and a computer solution to the analytical is obtained. The computer results are presented for a spacecraft in the vicinity of Earth, Venus, Mars, and the Moon. Each planetary body is assumed to be a spherical diffuse reflector with cylindrical shadows and a constant albedo. The data generated herein permit the selection of an appropriate coarse-sensor to fine-sensor switching angle for solar orientation control systems and facilitate the the interpretation of solar-referenced scientific experiment data.
SPACE ORIENTATION↗
Lunar slope angles and surface roughness from Ranger photographs.
Errors in estimates of lunar crater slope angles and surface roughness in Ranger VII and Ranger VIII pictures due to interpretation of dark areas as shadows
TOPOGRAPHY↗
Systems analysis research
Shadow equation for satellite, consistent ephemeris of major planets in solar system, correction process for lunar orbit, and numerical approximation of Hermite expansion
Source record↗
Theoretical study of the magnetic field in the lunar wake.
Magnetic field perturbations in lunar wake formed by dark side plasma shadow region due to solar wind interaction with moon
Whang, Y. C.↗
Thermal analysis of the Apollo - A computer technique which accounts for the influence of selfshadowing.
Apollo thermal control systems and concepts, discussing self shadowing
Brown, R. G.↗
Time variation of the altitude distribution of the ''cosmic'' dust layer in the upper atmosphere.
Time variation of altitude distribution of cosmic dust layer in upper atmosphere by Pandora II collector using inflight shadowing technique
Hallgren, D. S.↗
Optical probing of supersonic aerodynamic turbulence
Laser quasi-schlieren system and laser shadow-correlation system retrieve flow-related signals sufficient for computing accurate, reproducible correlation peaks. Statistical method for obtaining one-shot measurements of the decay history of turbulent structures in a stationary frame of reference is discussed.
Cikanek, H. A., Jr.↗
Interpretive and mosaicking problems of SLAR imagery
Side-looking airborne radars ground and slant range imagery mosaic preparation and geoscience interpretation, analyzing terrain geometry, radar shadow and layover
Lewis, A. J.↗
Earth's dust cloud
Hypothetical geocentric /interplanetary/ dust cloud concentration detection possibility by earth shadow
Roosen, R. G.↗
Dynamic upper atmospheric force model on stabilized vehicles for a high-precision trajectory computer program
The upper atmosphere model draws heavily on the behavior of the earth's upper atmosphere which exhibits cyclic as well as irregular variations in density profile, temperature, pressure, and composition in unison with solar activities as deduced from the more recent land-based and satellite observations. The lift and drag model is designed specifically for inertially stabilized vehicles of the Mariner class, with possible extension to gravity gradient stabilized vehicles of the GEOS class. The model considers operation in the free molecular flow regimes with large Knudsen numbers. The vehicle is considered a composite structure with basic components having well-defined shapes, each with its own surface characteristics in terms of temperature, reflectivity, and accommodation of free stream molecules. The model takes into account both the calculation of precise aerodynamic force coefficients in terms of expansion of modified Bessel functions in speed ratios and angle of attack, and approximate force coefficients when the speed ratios approach infinity. Other considerations include specular and diffused reflectivity, shielding, and shadow effects.
Khatib, A. R.↗
Geologic interpretation of Apollo 6 stereophotography from Baja California to west Texas
Excellent space photography of parts of the southwestern United States and northwestern Mexico was obtained during the unmanned Apollo 6 spaceflight. Two features of this photography made it useful for geologic interpretations: its vertical stereocoverage and its exposure under a relatively low angle of solar illumination through an unusually cloud-free and clear atmosphere. The structural patterns, which were topographically enhanced by the longer shadows, were annotated on the photographs, in order to analyze their trends with respect to the continental tectonic framework, and to attempt to correlate the pattern with known copper or other base metal deposits. The annotated fracture patterns showed the regional trends and their distribution. The area studied was a 100- to 105-mile swath of terrain covering a total land area of approximately 60,000 square statute miles. The coverage began from a point centered on Punta Colnett on the Pacific coast of Baja California and extended to the Sacramento Mountains of New Mexico and west Texas.
Gawarecki, S. J.↗
In-space fabrication of thin-film structures
A conceptual study of physical vapor-deposition processes for in-space fabrication of thin-film structures is presented. Potential advantages of in-space fabrication are improved structural integrity and surface reflectivity of free-standing ultra-thin films and coatings. Free-standing thin-film structures can find use as photon propulsion devices (solar sails). Other applications of the concept involve free-standing shadow shields, or thermal control coatings of spacecraft surfaces. Use of expendables (such as booster and interstage structures) as source material for the physical vapor deposition process is considered. The practicability of producing thin, textured, aluminum films by physical vapor deposition and subsequent separation from a revolving substrate is demonstrated by laboratory experiments. Heating power requirement for the evaporation process is estimated for a specific mission.
Lippman, M. E.↗
A preliminary shield design for a SNAP-8 power system
A preliminary shield design for a nuclear power system utilizing a SNAP-8 reactor for space base application is presented. A representative space base configuration was selected to set the geometry constraints imposed on the design. The base utilizes two independent power packages each with a reactor operating at 600 kwt and each producing about 50 kwe. The crew compartment is located about 200 feet from each reactor and is large enough in extent to intercept a total shadow angle of 60 deg measured about the center line of each reactor.
Karp, I. M.↗
On obtaining lunar mission launch opportunities
A general procedure for predicting launch opportunities for the RAE-B lunar orbiter mission is presented. It is shown that knowledge of the earth-moon distance and lunar phase and declination are sufficient to determine launch periods consistent with present mission constraints and to approximately predict launch, transfer, and arrival parameters such as park orbit coast time, the possiblity of shadows in all phases of the mission, arrival energy, and the amount of sunlit orbit time in the lunar orbit. Constraints on RAE-B include bounds on the spin axis-sun angle in the translunar trajectory, an upper limit on the arrival energy, and a minimum time for sunlight duration in lunar orbits are being considered for the mission. Comparisons are made of relevant parameters for the two cases. The general features of launch, transfer, and arrival parameters are discussed and are shown to be a function of lunar declination, flight time, and launch azimuth.
Swartwood, H., Jr.↗