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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 NTRS2001

Titan Orbiter Aerorover Mission

We propose a combined Titan orbiter and Titan Aerorover mission with an emphasis on both in situ and remote sensing measurements of Titan's surface, atmosphere, ionosphere, and magnetospheric interaction. The biological aspect of the Titan environment will be emphasized by the mission (i.e., search for organic materials which may include simple organics to 'amono' analogues of amino acids and possibly more complex, lightening detection and infrared, ultraviolet, and charged particle interactions with Titan's surface and atmosphere). An international mission is assumed to control costs. NASA will provide the orbiter, launch vehicle, DSN coverage and operations, while international partners will provide the Aerorover and up to 30% of the cost for the scientific instruments through collaborative efforts. To further reduce costs we propose a single PI for orbiter science instruments and a single PI for Aerorover science instruments. This approach will provide single command/data and power interface between spacecraft and orbiter instruments that will have redundant central DPU and power converter for their instruments. A similar approach could be used for the Aerorover. The mission profile will be constructed to minimize conflicts between Aerorover science, orbiter radar science, orbiter radio science, orbiter imaging science, and orbiter fields and particles (FP) science. Additional information is contained in the original extended abstract.

Sittler Jr., E. C.↗
NASA NTRS2004

Beagle 2: Mission to Mars - Current Status

Beagle 2 is a 72 kg probe (with a 32 kg lander) developed in the United Kingdom for inclusion on the European Space Agency's 2003 Mars Express. Beagle 2 was launched on June 2, 2003 with Mars Express on a Soyuz-Fregat rocket from the Baikonur Cosmodrome in Kazakhstan. Beagle 2 landed on Mars on December 25th, 2003 in Isidis Planitia (approx. 10.7 N and 268.6 W), a large sedimentary basin that overlies the boundary between ancient highlands and northern plains. Isidis Planitia, the third largest impact basin on Mars, which is possibly filled with sediment deposited at the bottom of long-standing lakes or seas, offers an ideal environment for preserving traces of life. The team is awaiting signals from the Beagle 2 lander at the time when this abstract was written. Current status of the mission will be reported. Beagle 2 was developed to search for organic material and other volatiles on and below the surface of Mars in addition to the study of the inorganic chemistry and mineralogy. Several fundamental properties can be used to determine the existence of an active or past biology on any planet, Earth or Mars. Beagle 2's targets for investigation included: (a) The presence of water, or the existence of minerals deposited from water to show that water was present, even if only transiently; (b) The detection of carbonaceous debris, the remains of organisms that might have lived in water or were washed to a final resting place by the action of water; (c) The structure of organic matter, to demonstrate that it might have been synthesized for a biological purpose; (d) The recognition of isotopic fractionation between carbonaceous phases (organic vs inorganic carbon phases), a condition which on Earth suggests that life emerged nearly 4 billion years ago.

Gibson, E. K., Jr.↗
NASA NTRS1976

Creation of a ceramics handbook

A group of common ceramic materials (alumina, magnesium oxide, silicon nitride, and silicon carbide) were characterized through literature searches according to their physical properties. The files used were the NASA file, DDC/GRA File, Engineering Index File and standard library searches. The results of these searches are arranged by material properties including mechanical, electrical, electromagnetic, where applicable, and fracture; and the entries are arranged in chronological order by candidate. A list, by author, follows where tabular information including charts and figures of results is given along with a brief statement of the results and conclusions. In both cases, information on the independent variables along with their range is given. The results of an extensive industry survey asking for names of other candidates on which information is lacking and also what type of service, if any, is desired in keeping a current information file on general ceramic materials.

Craft, W. J.↗
NASA NTRS2008

New Scintillator Materials (K2CeBr5) and (Cs2CeBr5)

Cesium cerium bromide (Cs2CeBr5) and potassium cerium bromide (K2CeBr5) are new scintillator materials for X-ray and gamma ray detector applications. Recently halide scintillator materials, such as Ce doped lanthanum bromide has been proved to be very important material for the same purpose. These materials are highly hygroscopic; a search for high light yield non-hygroscopic materials was highly desirable to advance the scintillator technology. In this paper, we are reporting the crystal growth of novel scintillator materials, cesium cerium bromide (Cs2CeBr5) and potassium cerium bromide (K2CeBr5). Crystals were successfully grown from the melt using the vertical Bridgman-Stockbarger technique, in a comparison with the high performance LaBr3 or LaCl3 crystals, cerium based alkali halides crystals, (Cs2CeBr5) and (K2CeBr5) have similar scintillation properties, while being much less hygroscopic. Furthermore, cesium based compounds will not suffer from the self-activity present in potassium and lanthanum compounds. However the Cs2CeBr5 crystals did not grow properly probably due to non-congruent melting or to some phase transition during cooling. Keywords." Scintillator materials; Ce3+; Energy resolution; Light yield; K2CeBr5

Hawrami, R.↗
NASA NTRS1988

Theoretical comparison of maser materials for a 32-GHz maser amplifier

The computational results of a comparison of maser materials for a 32 GHz maser amplifier are presented. The search for a better maser material is prompted by the relatively large amount of pump power required to sustain a population inversion in ruby at frequencies on the order of 30 GHz and above. The general requirements of a maser material and the specific problems with ruby are outlined. The spin Hamiltonian is used to calculate energy levels and transition probabilities for ruby and twelve other materials. A table is compiled of several attractive operating points for each of the materials analyzed. All the materials analyzed possess operating points that could be superior to ruby. To complete the evaluation of the materials, measurements of inversion ratio and pump power requirements must be made in the future.

Lyons, James R.↗
NASA NTRS2000

The Search for Water and Other Volatiles in Martian Surface Materials: The Thermal Evolved Gas Analyzer (TEGA)

Volatile-bearing minerals and phases (e.g., Fe-oxyhydroxides, phyllosilicates, carbonates, sulfates, palagonites, glasses) may be important components of the Martian regolith. However, essentially no information exists on the mineralogical composition of volatile-bearing phases in the regolith. The Thermal Evolved Gas Analyzer (TEGA), which was part of the Mars Polar Lander payload, was to determine the abundances of two of the most important volatile compounds (i.e., water and carbon dioxide) in the martian soil and to identify the minerals or phases that harbor these volatiles. The TEGA instrument was composed of a differential scanning calorimeter (DSC) interfaced with evolved gas analysis (EGA). The EGA consisted of a Herriott cell of a tunable-diode laser (TDL) spectrometer that determines CO2 and H2O abundances. The sample chamber was to operate at about 100 mbar (-76 torr) with a N2 carrier gas flow of 0.4 sccm. Specifications of TEGA are described in detail elsewhere in this volume.

Ming, D. W.↗
NASA NTRS1972

Investigation of superconducting interactions and amorphous semiconductors

Research papers on superconducting interactions and properties and on amorphous materials are presented. The search for new superconductors with improved properties was largely concentrated on the study of properties of thin films. An experimental investigation of interaction mechanisms revealed no new superconductivity mechanism. The properties of high transition temperature, type 2 materials prepared in thin film form were studied. A pulsed field solenoid capable of providing fields in excess of 300 k0e was developed. Preliminary X-ray measurements were made of V3Si to determine the behavior of cell constant deformation versus pressure up to 98 kilobars. The electrical properties of amorphous semiconducting materials and bulk and thin film devices, and of amorphous magnetic materials were investigated for developing radiation hard, inexpensive switches and memory elements.

Janocko, M. A.↗
NASA NTRS2015

Microstructural and Compositional Relations of Granitoid Clasts in Lunar Breccias at the Micrometer to Sub-Micrometer Scale

Lunar granitoid lithologies have long been of interest for the information they provide on processes leading to silicic melt compositions on the Moon. The extraction of such melts over time affects the distribution and budget of incompatible materials (i.e., radiogenic heat producing elements and volatiles) of the lunar interior. We have recently shown that in addition to their high concentrations of incompatible lithophile elements, some granitoid clasts in lunar breccias have significant indigenous water contents in their alkali feldspars. This raises the importance of lunar granitoid materials in the expanding search for mineralogic/petrologic hosts of indigenous lunar water-related species. We are undertaking a detailed survey of the petrologic/mineralogical relations of granitoid clasts in lunar breccias to achieve a better understanding of the potential of these diverse assemblages as hosts for volatiles, and as candidates for additional isotope chronology studies. Our preliminary results reported here based on high-resolution field-emission SEM, EPMA and TEM studies uncover immense complexity in these materials at the micrometer to sub-micrometer scale that heretofore have not been fully documented.

Christoffersen, R.↗
NASA NTRS1999

Seal Materials Compatible with the Electroplating Solvent Used in Constellation-X Mirrors

The existing gasket seals used in electroplating of the Constellation-X mirrors are difficult to assemble, and the current seal material is hydrophobic and too thick. The combination of the above problems result in: 1) non-uniform plating; 2) defect sites such as pits on the mirror edges; 3) "bear claws" on the edges of the mandrels and mirrors causing difficulties in shell-mirror separations; and 4) leakage of the plating solution past the seals into the mandrel causing chemical etching of the mandrel interior. This paper reports the results of this summer study in searching for alternate seal materials chemically compatible with the electroplating solvent. Fifteen common elastomeric rubber seal materials made-by Parker Seals were investigated including butyl, ethylene propylene, fluorosilicone, nitrile, Viton fluorocarbon, and silicone. Test results showed that Viton fluorocarbon compounds as a group were superior to the other tested compounds for chemical compatibility with the plating bath.

Pei, Xiong-Skiba↗
NASA NTRS1999

Looking for Fossil Bacteria in Martian Materials

The rationale for looking for prokaryote fossils in Martian materials is based on our present understanding of the environmental evolution of that planet in comparison to the history of the terrestrial environments and the development and evolution of life on Earth. On Earth we have clear, albeit indirect, evidence of life in 3.8 b.y.-old rocks from Greenland and the first morphological fossils in 3.3-3.5 b.y.-old cherts from South Africa and Australia. In comparison, Mars, being smaller, probably cooled down after initial aggregation faster than the Earth. Consequently, there could have been liquid water on its surface earlier than on Earth. With a similar exogenous and endogenous input of organics and life-sustaining nutrients as is proposed for the Earth, life could have arisen on that planet, possibly slightly earlier dm it did on Earth. Whereas on Earth liquid water has remained at the surface of the planet since about 4.4 b.y. (with some possible interregnums caused by planet-sterilising impacts before 3.8. b.y. and perhaps a number of periods of a totally frozen Earth, this was not the case with Mars. Although it is not known exactly when surficial water disappeared from the surface, there would have been sufficient time for life to have developed into something similar to the terrestrial prokaryote stage. However, given the earlier environmental deterioration, it is unlikely that it evolved into the eukaryote stage and even evolution of oxygenic photosynthesis may not have been reached. Thus, the impetus of research is on single celled life simnilar to prokaryotes. We are investigating a number of methods of trace element analysis with respect to the Early Archaean microbial fossils. Preliminary neutron activation analysis of carbonaceous layers in the Early Archaean cherts from South Africa and Australia shows some partitioning of elements such as As, Sb, Cr with an especial enrichment of lanthanides in a carbonaceous-rich banded iron sediment . More significantly, preliminary TOF-SIMS investigations of organics in the cherts reveals the presence of a biomarker, which appears to be a derivative of bacterial polymer, in the carbonaceous parts of the rocks. We conclude that a combination of morphological, isotope and biogeochemical methods can be used to successfully identify signs of life in terrestrial material, and that these methods will be useful in searching for signs of life in extraterrestrial materials.

Westall, F.↗
NASA NTRS1977

Complex refractive index of Martian dust - Wavelength dependence and composition

The size distribution and complex refractive index of Martian dust-cloud particles observed in 1971 with the Mariner 9 UV spectrometer are determined by matching the observed single-scattering albedo and phase function with Mie-scattering calculations for size distributions of spheres. Values of phase function times single-scattering albedo are presented for 12 wavelength intervals in the range from 190 to 350 nm, and best-fit values are obtained for the absorption index. It is found that the absorption index of the dust particles increases with decreasing wavelength from 350 to about 210 nm and then drops off shortward of 210 nm, with a structural shoulder occurring in the absorption spectrum between 240 and 250 nm. A search for a candidate material that can explain the strong UV absorption yields TiO2, whose anatase polymorph has an absorption spectrum matching that of the Martian dust. The TiO2 content of the dust particles is estimated to be a few percent or less.

Pang, K.↗
NASA NTRS1985

lasants for transfer blackbody-pumped lasers

The concept of transfer blackbody-pumped lasers is outlined, recent research results concerning these lasers are presented and the search for new lasant materials for transfer blackbody-pumped lasers is expanded. There are two basic concepts for the blackbody-pumped transfer laser which are schematically drawn. The first concept is called the translational heating concept, an example being N2:CO2. Here the blackbody cavity is heated to approximately 2000 K by collected sunlight in space. An absorbing molecule would come in contact with the blackbody walls thus coming into equilibrium with the blackbody temperature. An alternative concept shown is called the vibrational heating transfer laser. Here the absorbing molecule is not translationally heated. Energy is coupled to the molecule only by optical absorption creating a high density of vibrational states. Thus the gas temperature is near room temperature whereas the vibrational temperature comes into equilibrium with the blackbody temperature.

Deyoung, R. J.↗
NASA NTRS1952

Experimental Aerodynamic Derivatives of a Sinusoidally Oscillating Airfoil in Two-Dimensional Flow

Experimental measurements of the aerodynamic reactions on a symmetrical airfoil oscillating harmonically in a two-dimensional flow are presented and analyzed. Harmonic motions include pure pitch and pure translation, for several amplitudes and superimposed on an initial angle of attack, as well as combined pitch and translation. The apparatus and testing program are described briefly and the necessary theoretical background is presented. In general, the experimental results agree remarkably well with the theory, especially in the case of the pure motions. The net work per cycle for a motion corresponding to flutter is experimentally determined to be zero. Considerable consistent data for pure pitch were obtained from a search of available reference material, and several definite Reynolds number effects are evident.

Halfman, Robert L↗
NASA NTRS1994

Outgassing of solid material into vacuum thermal insulation spaces

Many cryogenic storage tanks use vacuum between inner and outer tank for thermal insulation. These cryogenic tanks also use a radiation shield barrier in the vacuum space to prevent radiation heat transfer. This shield is usually constructed by using multiple wraps of aluminized mylar and glass paper as inserts. For obtaining maximum thermal performance, a good vacuum level must be maintained with the insulation system. It has been found that over a period of time solid insulation materials will vaporize into the vacuum space and the vacuum will degrade. In order to determine the degradation of vacuum, the rate of outgassing of the insulation materials must be determined. Outgassing rate of several insulation materials obtained from literature search were listed in tabular form.

Wang, Pao-Lien↗