8,121 research outputs found
Extraction of volatile and metals from extraterrestrial materials
Since March 1, 1989, attention was concentrated on the extraction of ilmenite from extraterrestrial materials and on the planning and development of laboratory facilities for carbonyl extraction of ferrous metal alloys. Work under three subcontracts was administered by this project: (1) electrolytic production of oxygen from molten lunar materials; (2) microwave processing of lunar materials; and (3) production of a resource-oriented space science data base
Extraction of volatiles and metals from extraterrestrial ores
Extraterrestrial materials, processes, and products were identified which are associated with the production of propellants in space, including the most complete possible conversion of the feedstocks for propellant production into useful products with the minimum feasible expenditure of energy. Laboratory research was identified and begun on several processes that promise very large increases in the mass of useful products at the cost of only modest increases in energy consumption. Processes for manufacturing propellants then become processes for making propellants plus metals and refractories. It is the overall yield of useful materials per unit expended energy that matters, not simply the yield of propellants. Three tasks have been undertaken to date: (1) Literature search and compilation of a dBase 3 data base on space materials processing; (2) Gaseous carbonyl extraction and purification of ferrous metals; and (3) Characterization of lunar ilmenite and its simulants
Coproduction of volatiles and metals from extraterrestrial materials
Two main efforts in support of the general goals of SERC/culpr are presented. Investigations of processes for the coproduction of metals from extra-terrestrial materials in conjunction with plausible schemes for oxygen extraction continue. The principal emphasis was on the extraction and purification of iron from the ilmenite reduction process for oxygen, from the cathode metal deposits made in the magma electrolysis process for oxygen, and from native ferrous metal alloys on the moon and asteroids. All work on the separation and purification of ferrous metals was focussed upon the gaseous carbonyl process, a scheme that involves only temperatures attainable by passive thermal control. The exploration of a variety of schemes was initiated, involving the use of several different propulsion options and both propulsive and aerobraking capture at earth, for return of extraterrestrial resources to earth orbits. In addition, the search for new opportunities in space resource utilization continues. Examples include the continuation of work underway on: (1) the feasibility of locating solar power satellites in highly eccentric earth orbit; (2) the energetics of extracting the potential clean fusion fuel He-3 from the atmosphere for return to earth; and (3) the utility of a nuclear steam rocket (using non-terrestrial water as the working fluid) for transportation in the inner solar system
Origin and evolution of planetary atmospheres
This report concerns several research tasks related to the origin and evolution of planetary atmospheres and the large-scale distribution of volatile elements in the Solar System. These tasks and their present status are as follows: (1) we have conducted an analysis of the volatility and condensation behavior of compounds of iron, aluminum, and phosphorus in the atmosphere of Venus in response to publish interpretations of the Soviet Venera probe XRF experiment data, to investigate the chemistry of volcanic gases, injection of volatiles by cometary and asteroidal impactors, and reactions in the troposphere; (2) we have completed and are now writing up our research on condensation-accretion modeling of the terrestrial planets; (3) we have laid the groundwork for a detailed study of the effects of water transport in the solar nebula on the bulk composition, oxidation state, and volatile content of preplanetary solids; (4) we have completed an extensive laboratory study of cryovolcanic materials in the outer solar system; (5) we have begun to study the impact erosion and shock alteration of the atmosphere of Mars resulting from cometary and asteroidal bombardment; and (6) we have developed a new Monte Carlo model of the cometary and asteroidal bombardment flux on the terrestrial planets, including all relevant chemical and physical processes associated with atmospheric entry and impact, to assess both the hazards posed by this bombardment to life on Earth and the degree of cross-correlation between the various phenomena (NO(x) production, explosive yield, crater production, iridium signature, etc.) that characterize this bombardment. The purpose of these investigations has been to contribute to the developing understanding of both the dynamics of long-term planetary atmosphere evolution and the short-term stability of planetary surface environments
Asteroid resources
There are three types of possible asteroidal materials that appear to be attractive for exploitation: (1) volatiles, (2) free metals, and (3) bulk dirt. Because some of the near-Earth asteroids are energetically more accessible than the Moon (require a round-trip total change in velocity less than 9 km/sec, though the trip time would be measured in years not days), such an asteroid might be chosen as the source of any useful material, even if that material was also available on the Moon. Provided that the asteroid was minable, it might therefore be chosen as the source of bulk dirt needed for shielding in low Earth orbit (LEO) or elsewhere in near-Earth space. And the near-Earth asteroids may offer materials that are rare or absent on the surface of the Moon. The relationship between asteroids and meteorites is discussed. A brief overview of the entire range of meteorite compositions, with emphasis on the occurrence of interesting resources is presented. Focus is on materials useful in space, especially volatiles, metals, and raw dirt. Those few materials that may have sufficiently high market value to be worth returning to Earth will be mentioned
NASA Space Engineering Research Center for Utilization of Local Planetary Resources
Progress toward the goal of exploiting extraterrestrial resources for space missions is documented. Some areas of research included are as follows: Propellant and propulsion optimization; Automation of propellant processing with quantitative simulation; Ore reduction through chlorination and free radical production; Characterization of lunar ilmenite and its simulants; Carbothermal reduction of ilmenite with special reference to microgravity chemical reactor design; Gaseous carbonyl extraction and purification of ferrous metals; Overall energy management; and Information management for space processing
The Agricultural Potential of the Middle Kuskokwim Valley
Alaskans are concerned with the production of food . This is evident
from the concern which has been expressed over the subsistence
issue within the current Alaska lands legislation. The debate ponders
who shall harvest the state's natural game resource and how the
resource shall be harvested. Although this question is not settled , one
point is coming to the fore: the game resource alone is not sufficient
to satisfy the food needs of Alaska's growing rural population.
In recent months, interest has been expressed in the agricultural
potential of the lands in areas of Alaska which are removed from
major population centers and from connecting surface transportation
routes. One area in particular in southwestern Alaska has made significant
progress in agricultural development. The Kuskokwim Native
Association has maintained a community garden since 1976 in Aniak
on the Kuskokwim River (Figure 1) (Lewis, Thomas, and Wooding,
1978). This effort could be expanded using existing transportation
corridors to supply not only the Kuskokwim River valley, but also
several villages located away from the river.
The objective of this study is to provide an economic evaluation of
the feasibility of producing and marketing vegetables in the Kuskokwim
River valley area. Major considerations were the availability of
markets, transportation, and a method of product distribution. All
were based on production capability of the area and the capacity and
time factors pertaining to vegetable storage.The research necessary to prepare this report was funded in part
by the Bureau of Indian Affairs, Contract Number EOOC14201592.
This report was prepared using data derived from the garden project
undertaken by the Kuskokwim Native Association in Aniak, Alaska,
for the years 1976 through 1978. Those associated with the project,
particularly former manager David Hassinger, the Kuskokwim Native
Association Board of Directors, and the residents of the Kuskokwim
River area, are acknowledged for their assistance. In those cases
where data were not available they were provided by the following
resource persons and agencies : Dr. Frank J. Wooding, Associate
Professor of Agronomy, and Dr. Donald H. Dinkel, Professor of Plant
Physiology, Agricultural Experiment Station, University of Alaska,
Fairbanks; Dr. Curtis H. Dearborn, Research Horticulturist, and Dr.
Richard H. 'Washburn (deceased), Research Entomologist, Agricultural
Research Service, United States Department of Agriculture,
Palmer, Alaska; Edward Kern, Marketing Specialist, Alaska State
Division of Agriculture, Palmer, Alaska; and Dr. Charles E. Logsdon,
Agresources, Palmer, Alaska. Pat Barker, Cooperative Extension
Service, University of Alaska, Bethel, Alaska, is also thanked for
helping us to obtain information concerning Bethel area markets.
Particular thanks is given Dr. Wayne C. Thomas, Associate Professor
of Economics, Agricultural Experiment Station, University of
Alaska, Fairbanks, Alaska, for his comments throughout the project
and extensive review of this report
In-Space Production of Storable Propellants
Our exploration of the feasibility of in-space production of storable propellants from resourcesavailable on asteroids, and also on Mars and the Moon, has considered the process of sampleacquisition; the energy requirements for heating and volatile release; the thermodynamic behaviorof gas release from minerals and organic polymers containing hydrogen, oxygen, carbon, sulfur,and nitrogen; purification of the released water and carbon dioxide; the storage and transportation of these materials in the condensed state; synthesis of fuels including methanol and dimethyl ether(DME); and the co-production, concentration, stability, and storage of the complementary oxidizer high-test hydrogen peroxide (HTP). We call attention to the ability of the storable propellant/oxidizer combination of DME and HTP to carry out deep-space missions and to perform retrieval and relocation of any and all space-derived resources, such as retrieving asteroidal metal to high Earth orbit. This study's analyses are based on returning resources to a storage/processing/dispensing facility in a Highly Eccentric Earth Orbit (HEEO) with a perigee above geosynchronous orbit and an apogee approach or beyond the Moon's orbit.The methane/LOX option, notable for good engine performance, has not been included in this study because our scope includes only fully storable propellants
Randomized Rounding for the Largest Simplex Problem
The maximum volume -simplex problem asks to compute the -dimensional
simplex of maximum volume inside the convex hull of a given set of points
in . We give a deterministic approximation algorithm for this
problem which achieves an approximation ratio of . The problem
is known to be -hard to approximate within a factor of for
some constant . Our algorithm also gives a factor
approximation for the problem of finding the principal submatrix of
a rank positive semidefinite matrix with the largest determinant. We
achieve our approximation by rounding solutions to a generalization of the
-optimal design problem, or, equivalently, the dual of an appropriate
smallest enclosing ellipsoid problem. Our arguments give a short and simple
proof of a restricted invertibility principle for determinants
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