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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 73 records · Page 4
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NASA NTRS2021

An evolutionary system of mineralogy, Part V: Aqueous and thermal alteration of planetesimals (~4565 to 4550 Ma)

Part V of the evolutionary system of mineralogy explores phases produced by aqueous alteration, metasomatism, and/or thermal metamorphism—relicts of ancient processes that affected virtually all asteroids and that are preserved in the secondary mineralogy of meteorites. We catalog 166 historical natural kinds of minerals that formed by alteration in the parent bodies of chondritic and non-chondritic meteorites within the first 20 Ma of the solar system. Secondary processes saw a dramatic increase in the chemical and structural diversity of minerals. These phases incorporate 41 different mineral-forming elements, including the earliest known appearances of species with essential Co, Ge, As, Nb, Ag, Sn, Te, Au, Hg, Pb, and Bi. Among the varied secondary meteorite minerals are the earliest known examples of halides, arsenides, tellurides, sulfates, carbonates, hydroxides, and a wide range of phyllosilicates.

Robert M. Hazen↗
NASA NTRS2021

An Evolutionary System of Mineralogy. Part III: Primary Chondrule Mineralogy (4566 to 4561 Ma)

Information-rich attributes of minerals reveal their physical, chemical, and biological modes of origin in the context of planetary evolution, and thus they provide the basis for an evolutionary system of mineralogy. Part III of this system considers the formation of 43 different primary crystalline and amorphous phases in chondrules, which are diverse igneous droplets that formed in environments with high dust/gas ratios during an interval of planetesimal accretion and differentiation between 4566 and 4561 Ma. Chondrule mineralogy is complex, with several generations of initial droplet formation via various proposed heating mechanisms, followed in many instances by multiple episodes of reheating and partial melting. Primary chondrule mineralogy thus reflects a dynamic stage of mineral evolution, when the diversity and distribution of natural condensed solids expanded significantly.

Classification↗
NASA NTRS1971

Space station MSFC-DPD-235/DR no. MA-05 phase C/D program development plan. Volume 2: Phase C/D, programmatic requirements

The design plan requirements define the design implementation and control requirements for Phase C/D of the Modular Space Station Project and specifically address the Initial Space Station phase of the Space Station Program (modular). It is based primarily on the specific objective of translating the requirements of the Space Station Program, Project, Interface, and Support Requirements and preliminary contract end x item specifications into detail design of the operational systems which comprise the initial space station. This document is designed to guide aerospace contractors in the planning and bidding for Phase C/D.

Source record↗
NASA NTRS1975

Monotectic and syntectic alloys: ASTP experiment MA-044

A postflight preliminary technical evaluation is presented of the returned samples of aluminum antimonide (AlSb) syntectic compound and lead-zinc (PbZn) monotectic immiscible processed during the Apollo-Soyuz Test Project (ASTP) mission. The returned cartridges, extracted ampoules, and removed samples were examined in detail. A genesis of the experiment is given along with a summary of the efforts and various scheduled tests up to the ASTP mission. A tentative characterization plan is developed from the postflight preliminary examination which makes use of the limited number of available samples and is based on the initial observations. It is indicated that a higher degree of compositional homogeneity in aluminum antimonide was achieved under flight test conditions.

Ang, C. Y.↗
NASA NTRS1976

Soft X-ray observation experiment MA-048

The Apollo Soyuz Test Project Soft X-ray Experiment was designed to observe celestial X-ray sources in the energy range from 0.1 to 10 kiloelectronvolts. The instrument that was used in the experiment obtained energy and fast timing data to characterize both the spectrum and the variability of known X-ray sources. Data were obtained on approximately 12 sources. During the mission, the instrument developed an intermittent high voltage discharge problem that resulted in the loss of approximately 75 percent of the anticipated data, including the scans intended for mapping of the low energy diffuse X-ray background.

Shulman, S.↗
NASA NTRS1976

Extreme ultraviolet survey experiment MA-083

A grazing incidence telescope sensitive to radiation in the 5- to 100-nanometer band was flown in the Apollo service module. On 10 nighttime revolutions, the command and service module was maneuvered to point the instrument at 30 different stellar targets for periods of 1 to 20 minutes, thus constituting the first sensitive search for extreme ultraviolet radiation from nonsolar sources. Several hours of supplementary data were also obtained during nighttime orbits when other experiments in the scientific instrument module bay were operating. Preliminary analysis of a small fraction of the total data indicates the definite detection of a strong source of extreme ultraviolet radiation during observations made during revolution 109. The source is located in Coma Berencies. The suggested optical identification is the white dwarf HZ 43. If this association is correct, the star has the highest temperature of any known white dwarf. Regardless of the optical identification, however, this object is the first nonsolar source to be detected in the extreme ultraviolet band.

Bowyer, S.↗
NASA NTRS1976

Artificial solar eclipse experiment MA-148

On July 19, 1975, the Apollo spacecraft successfully occulted the solar disk from the field of view of a camera mounted in the Soyuz spacecraft while performing a spacecraft separation maneuver to permit the outer solar corona to be viewable by the Soyuz camera. The camera operated automatically, and 55 frames were developed for scientific analysis.

Giuli, R. T.↗
NASA NTRS1976

Crystal activation experiment MA-151

The crystal activation experiment consisted of two sample packages that were flown in the command module and returned to earth for analysis of the radioactivity induced in them during the flight. The objective of the experiment was to define the background caused by detector activation that interferes when gamma radiation is measured in the 0.02- to 10-megaelectronvolt range from earth orbit. Preliminary results show that the activation of the NaI(Tl) crystal was a factor of 3 below that from a similar measurement on Apollo 17. The identification of certain species and the level of activation observed show an important contribution from the interactions of thermal and energetic neutrons produced as secondaries in the spacecraft. That the activation was reduced by only a factor of 3 compared with the Apollo 17 experiment, despite the geomagnetically shielded orbit, possibly indicates more efficient secondary neutron production by the more energetic cosmic rays.

Trombka, J. I.↗
NASA NTRS1976

Ultraviolet absorption experiment MA-059

The ultraviolet absorption experiment performed during the Apollo Soyuz mission involved sending a beam of atomic oxygen and atomic nitrogen resonance radiation, strong unabsorbable oxygen and nitrogen radiation, and visual radiation, all filling the same 3 deg-wide field of view from the Apollo to the Soyuz. The radiation struck a retroreflector array on the Soyuz and was returned to a spectrometer onboard the Apollo. The density of atomic oxygen and atomic nitrogen between the two spacecraft was measured by observing the amount of resonance radiation absorbed when the line joining Apollo and Soyuz was perpendicular to their velocity with respect to the ambient atmosphere. Information concerning oxygen densities was also obtained by observation of resonantly fluorescent light. The absorption experiments for atomic oxygen and atomic nitrogen were successfully performed at a range of 500 meters, and abundant resonance fluorescence data were obtained.

Donahue, T. M.↗
NASA NTRS1976

Stratospheric aerosol measurement experiment MA-007

The Apollo Soyuz Test Project Stratospheric Aerosol Measurement Experiment was flown to demonstrate that direct solar occultation measurements by photometers and photographs can be used for defining stratospheric aerosol concentrations. Supporting ground truth data were provided by laser radar and balloon borne dustsonde. Initial results show a significant difference in aerosol concentrations between the Northern and Southern Hemispheres.

Pepin, T. J.↗
NASA NTRS1976

Earth observations and photography experiment MA-136

The primary objectives of the earth observations and photography experiment of the Apollo Soyuz Test Project were to photograph various terrestrial structures and to use the capabilities of man as a trained observer in visually studying earth features and phenomena. Man's special capabilities include the sensitivity of the eye to subtle color variations and the speed with which the eye/brain system can interpret what is seen and select targets for photography. Real time astronaut observations constitute a useful complement to orbital photographs and greatly aid in their interpretation. Targets for mapping and hand held photography were selected on the basis of their value to specialists in the earth sciences including geology, oceanography, desert study, hydrology, meteorology, and environmental science.

El-Baz, F.↗
NASA NTRS1976

Doppler tracking experiment MA-089

The Doppler tracking experiment was designed to test the feasibility of improved mapping of earth gravity field anomalies by means of the low-low satellite-to-satellite tracking method. All prescribed data have been retrieved and are currently being reduced and analyzed. Baseline data taken while the docking module was still attached to the command and service module indicated that the equipment operated satisfactorily. The efficacy of the two frequency ionospheric correction method has been demonstrated, and preliminary reduction of a data sample has successfully removed extraneous signatures down to the 50-millihertz level, where the rotational motion of the docking module is revealed. Photographs of the docking module, taken shortly after jettison, show that its rotation was stable.

Weiffenbach, G. C.↗
NASA NTRS1976

Geodynamics experiment MA-128

The Apollo Soyuz Test Project Geodynamics Experiment was performed to assess the feasibility of tracking and recovering high frequency components of the earth gravity field by utilizing a synchronous orbiting tracking station such as Applications Technology Satellite 6. Two prime areas of data collection were selected for this experiment. The first area is the center of the African continent, and the second area is the Indian Ocean depression centered at latitude 5 N and longitude 75 E. Preliminary results show that the detectability objective of the experiment has been achieved in both areas as well as in several additional anomalous areas around the globe. Gravity anomalies of the Karakoram and Himalayan mountain ranges of ocean trenches, and of the Diamantina depth are specific examples.

Vonbun, F. O.↗