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Allen, Carlton C.

Publications and source records attributed to Allen, Carlton C..

79 records · Page 5

Characterization of the Resource Potential of Martian Soil using the Integrated Dust/Soil Experiment Package (IDEP)

The Integrated Dust/Soil Experiment Package (IDEP) is a suite of instruments that can detect and quantify the abundances of useful raw materials on Mars. We focus here on its capability for resource characterization in the martian soil; however, it is also capable of detecting and quantifying gases in the atmosphere. This paper describes the scientific rationale and the engineering design behind the IDEP.

Cooper, Bonnie L.↗

Experimental reduction of lunar mare soil and volcanic glass

We have reduced high-titanium lunar mare soil and iron-rich lunar volcanic glass with hydrogen at temperatures of 900-1100 C. Ilmenite is the most reactive phase in the soil, exhibiting rapid and complete reduction at all temperatures. Ferrous iron in the glass is extensively reduced concurrent with partial crystallization. In both samples pyroxene and olivine undergo partial reduction along with chemical and mineralogical modifications. High-temperature reduction provides insight into the optical and chemical effects of lunar soil maturation, and places constraints on models of that process. Mare soil and volcanic glass are attractive feedstocks for lunar oxygen production, with achievable yields of 2-5 wt%.

Allen, Carlton C.↗

Reduction of lunar basalt 70035: Oxygen yield and reaction product analysis

Oxygen production from a lunar rock has been experimentally demonstrated for the first time. A 10 g sample of high-Ti basalt 70035 was reduced with hydrogen in seven experiments at temperatures of 900-1050 C and pressures of 14.7-150 psia. In all experiments, water evolution began almost immediately and was essentially complete in tens of minutes. Oxygen yields ranged from 2.93 to 4.61% of the starting sample weight, and showed weak dependence on temperature and pressure. Analysis of the solid samples demonstrated total reduction of Fe(2+) in ilmenite and small degrees of reduction in olivine and pyroxene. Ti O2 was also partially reduced to one or more suboxides. Data from these experiments provide a basis for predicting the yield of oxygen from lunar basalt as well as new constraints on natural reduction in the lunar regolith.

Gibson, Michael A.↗

Ferromagnetic resonance spectra of H2-reduced minerals and glasses

In an earlier paper, we reported that H2 reduction of basaltic glass, olivine, pyroxene, and plagioclase resulted in the formation of metallic iron, in the darkening and reddening of the reflectance spectra, and the masking of individual spectral features in the visible and near-IR. In this work, we report FMR spectra for H2-reduced minerals and glasses that include the samples studied in the earlier paper. The FMR spectra were reduced at room temperature at a nominal frequency of 9.5 GHz. Sample saturation magnetization reported as F3(0) was measured with a vibrating sample magnetometer.

Morris, Richard V.↗

Sampling Elysium lavas (13 deg N, 203 deg W)

The proposed Pathfinder landing site presents the opportunity to determine chemical and mineralogical compositions of an Elysium lava flow. The flow is part of a geologic unit of planetary significance. The proposed site appears suitable for landing, and lava surfaces should be accessible to the Pathfinder instruments. By analogy to terrestrial flood basalts, any lava analyzed by Pathfinder is likely to be representative of the entire Elysium province.

Allen, Carlton C.↗

JSC-1: A new lunar regolith simulant

Simulants of lunar rocks and soils with appropriate properties, although difficult to produce in some cases, will be essential to meeting the system requirements for lunar exploration. In order to address this need a new lunar regolith simulant, JSC-1, has been developed. JSC-1 is a glass-rich basaltic ash which approximates the bulk chemical composition and mineralogy of some lunar soils. It has been ground to produce a gain size distribution approximating that of lunar regolith samples. The simulant is available in large quantities (greater than 2000 lb; 907 kg). JSC-1 was produced specifically for large- and medium-scale engineering studies in support of future human activities on the Moon. Such studies include material handling, construction, excavation, and transportation. The simulant is also appropriate for research on dust control and spacesuit durability. JSC-1 can be used as a chemical or mineralogical analog to some lunar soils for resource studies such as oxygen or metal production, sintering, and radiation shielding.

Mckay, David S.↗

Lunar oxygen - The reduction of glass by hydrogen

The direct reduction of volcanic glass by hydrogen has been proposed as a method of extracting oxygen from the lunar soil. Experiments using lunar simulant glasses reacted with flowing hydrogen gas have demonstrated reduction at temperatures from 1000 to 1200 C. For melted samples ferrous iron was reduced to the metal, which formed large crystals at the expense of the glass. Samples held below the melting point rapidly devitrified, and iron was formed from submicrometer crystals of ilmenite and pyroxene. Weight losses of 3.6 - 4.5 percent, depending on glass composition, were achieved in 3 hours at 1100 C. A lunar oxygen plant operating at this efficiency and utilizing Apollo 17 orange glass as a feedstock could produce 50 kg of oxygen per ton of soil. The processes of reduction and sintering of lunar soil are synergistic, and could be combined to produce both oxygen and construction material at a moon base.

Allen, Carlton C.↗