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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 325 records · Page 18
All sourcesNASA NTRSDOE OSTI
NASA NTRS1988

Lunar lander conceptual design: Lunar base systems study task 2.2

This study is a first look at the problem of building a lunar lander to support a small lunar surface base. One lander, which can land 25 metric tons, one way, or take a 6 metric ton crew capsule up and down is desired. A series of trade studies are used to narrow the choices and provide some general guidelines. Given a rough baseline, the systems are then reviewed. A conceptual design is then produced. The process was only carried through one iteration. Many more iterations are needed. Assumptions and groundrules are considered.

Source record↗
NASA NTRS1988

Lunar resources - Evaluation and development for use in a lunar base program

The implications of lunar crust characteristics for human habitation on the moon are considered. Sources for propellants in the crust are discussed, and the rationale for including mining among base objectives is examined. Present opportunities for extracting lunar crust resources are addressed.

Burke, J. D.↗
NASA NTRS1988

Growth of plant tissue cultures in simulated lunar soil: Implications for a lunar base CELSS (Controlled Ecological Life Support System)

Experiments were carried out on plant tissue cultures, seed germination, seedling development and plants grown on Simulated Lunar Soil to evaluate the potential of future development of lunar based agriculture. The studies done to determine the effect of the placement of SLS on tissue cultures showed no adverse effect of SLS on tissue cultures. Although statistically insignificant, SLS in suspension showed a comparatively higher growth rate. Observations indicate the SLS, itself cannot support calli growth but was able to show a positive effect on growth rate of calli when supplemented with MS salts. This positive effect related to nutritive value of the SLS was found to have improved at high pH levels, than at the recommended low pH levels for standard media. Results from seed germination indicated that there is neither inhibitory, toxicity nor stimulatory effect of SLS, even though SLS contains high amounts of aluminum compounds compared to earth soil. Analysis of seeding development and growth data showed significant reduction in growth rate indicating that, SLS was a poor growth medium for plant life. This was confirmed by the studies done with embryos and direct plant growth on SLS. Further observations attributed this poor quality of SLS is due to it's lack of essential mineral elements needed for plant growth. By changing the pH of the soil, to more basic conditions, the quality of SLS for plant growth could be improved up to a significant level. Also it was found that the quality of SLS could be improved by almost twice, by external supply of major mineral elements, directly to SLS.

Venketeswaran, S.↗
NASA NTRS1988

Conceptual design of a lunar base solar power plant lunar base systems study task 3.3

The best available concepts for a 100 kW Solar Lunar Power Plant based on static and dynamic conversion concepts have been examined. The two concepts which emerged for direct comparison yielded a difference in delivered mass of 35 MT, the mass equivalent of 1.4 lander payloads, in favor of the static concept. The technologies considered for the various elements are either state-of-the-art or near-term. Two photovoltaic cell concepts should receive high priority for development: i.e., amorphous silicon and indium phosphide cells. The amorphous silicon, because it can be made so light weight and rugged; and the indium phosphide, because it shows very high efficiency potential and is reportedly not degraded by radiation. Also the amorphous silicon cells may be mounted on flexible backing that may roll up much like a carpet for compact storage, delivery, and ease of deployment at the base. The fuel cell and electrolysis cell technology is quite well along for lunar base applications, and because both the Shuttle and the forthcoming Space Station incorporate these devices, the status quo will be maintained. Early development of emerging improvements should be implemented so that essential life verification test programs may commence.

Source record↗
NASA NTRS1988

A manned lunar outpost. Design considerations for three key elements in an initial manned lunar outpost

The Initial Manned Lunar Outpost (IMLO) is proposed as the initial permanent base for manned activities on the Moon. The study concentrated on identifying the equipment, support systems, and initial base configuration necessary to accomplish the various science, industrial and exploration activities planned. The primary concepts of the MLO were the use of hard modules for habitation areas creating a flexible, modular transportation system; designing a multi-functional vehicle; and using an overhead radiation protection system. The transportation system, dubbed the Lunar Mobile Surface Transport System (LMSTS), carries the hard modules to the surface of the moon and provides a method to move them to the desired location through the use of interchangeable pallets. The avionics pallets are changed-out with wheel and hitch pallets, transforming the LMSTS into a "tractor trailer" used with the Multi-Functional Vehicle (MFV). The modules are placed under the Regolith Support Structure (RSS) which provides a stable environment and radiation protection for the entire base. The overhead structure was chosen over simply burying the modules to provide a study on the advantages and disadvantages of this type of system. The advantages include easy access to the exterior of the modules, providing a protected area for vehicles and equipment used in EVA, and creating an area of constant temperature. Disadvantages include a need for prefabrication of structural components, including the preconstruction and construction phases of the initial MLO. The design approach taken considered existing and near-term materials and technology only, without the consideration of possible future building technologies.

Bell, Larry↗
NASA NTRS1990

Structural concept studies for a horizontal cylindrical lunar habitat and a lunar guyed tower

A conceptual structural design of a horizontal cylindrical lunar habitat is presented. The design includes the interior floor framing, the exterior support structure, the foundation mat, and the radiation shielding. Particular attention was given on its efficiency in shipping and field erection, and on selection of structural materials. Presented also is a conceptual design of a 2000-foot lunar guyed tower. A special field erection scheme is implemented in the design. In order to analyze the over-all column buckling of the mast, where its axial compression includes its own body weight, a simple numerical procedure is formulated in a form ready for coding in FORTRAN. Selection of structural materials, effect of temperature variations, dynamic response of the tower to moonquake, and guy anchoring system are discussed. Proposed field erection concepts for the habitat and for the guyed tower are described.

Yin, Paul K.↗
NASA NTRS1992

Receiver performance of laser ranging measurements between the Lunar Observer and a subsatellite for lunar gravity studies

The optimal receiver for a direct detection laser ranging system for slow Doppler frequency shift measurement is shown to consist of a phase tracking loop which can be implemented approximately as a phase lock loop with a 2nd or 3rd order loop filter. The laser transmitter consists of an AlGaAs laser diode at a wavelength of about 800 nm and is intensity modulated by a sinewave. The receiver performance is shown to be limited mainly by the preamplifier thermal noise when a silicon avalanche photodiode is used. A high speed microchannel plate photomultiplier tube is shown to outperform a silicon APD despite its relatively low quantum efficiency at wavelengths near 800 nm. The maximum range between the Lunar Observer and the subsatellite for lunar gravity studies is shown to be about 620 km when using a state-of-the-art silicon APD and about 1000 km when using a microchannel plate photomultiplier tube in order to achieve a relative velocity measurement accuracy of 1 millimeter per second. Other parameters such as the receiver time base jitter and drift also limit performance and have to be considered in the design of an actual system.

Davidson, Frederic M.↗
NASA NTRS1991

Large scale lunar horizon glow and a high altitude lunar dust exosphere

All three Apollo 17 astronauts sketched a `lunar horizon glow', seen from orbit above the moon. It is shown that the shape of the glow is compatible with scattering of sunlight off of gas or dust at high altitudes above the moon. The present mathematical modeling best simulates the glow with submicron dust grains whose spatial density varies with altitude above the moon as exp(-H/H(s)), where H(s) is in the range of 5 to 20 km. These dust grains are probably electrically charged and ejected above the lunar surface by local electric fields.

Zook, Herbert A.↗
NASA NTRS1990

Lunar samples, lunar accretion and the early bombardment of the moon

The cratering history of the moon is reexamined taking data acquired over the last decade into account along with a newly accepted concept concerning the moon's origin. It is found that predictions of a heavy bombardment are not fulfilled by lunar characteristics as understood from sample and remote sensing studies, nor by lunar accretion history. There is strong evidence for the reality for a short, intense, cataclysmic bombardment at about 3.85 Ga.

Ryder, Graham↗
NASA NTRS1992

U-Th-Pb, Rb-Sr, and Sm-Nd isotopic systematics of lunar troctolitic cumulate 76535 - Implications on the age and origin of this early lunar, deep-seated cumulate

The U-Th-Pb, Rb-Sr, and Sm-Nd isotopic systematics of four lightly leached residues of pristine, high-Mg, troctolitic cumulate 76535 were analyzed in order to determine their ages and magma sources. The data indicate that the cumulate was in isotopic equilibrium with a fluid or magma characterized by a high U-238/Pb-204 (mu) value of 600 at 4.236 Ga. Two and three stage Pb evolution calculations define even greater source mu values of about 1000, assuming low lunar initial mu values between 5 and 40 prior to about 4.43 Ga. These results are similar to mu values for KREEP sources and are also consistent with values from 78235, suggesting that at least some high-Mg suite rocks were derived from magma sources with high-mu values similar to KREEP, and support that idea that these rocks postdate primary lunar differentiation and formation of ferroan anorthosites.

Premo, Wayne R.↗
NASA NTRS1992

Robotic lunar exploration using the Pegasus winged rocket and ballistic lunar capture - An update

The present concept for robotic lunar missions combines Pegasus-launched small vehicles with the weak-stability boundary (WSB) or 'ballistic capture' trajectory suggested by Belbruno (1991). The existence of the earth's WSB, as a result of a distance from the sun of about 1.5 million km, yields a transfer that is analogous to the parabolic case but in which the earth-to-moon transit time is only 3-5 months. The WSB technique has been demonstrated by the Japanase Hiten spacecraft, which reached the lunar vicinity after 5 months in transit.

Belbruno, Edward A.↗
NASA NTRS1992

Solar cells for lunar applications by vacuum evaporation of lunar regolith materials

The possibility of the direct fabrication of solar cells on the lunar surface by the vacuum evaporation of lunar regolith is examined as an alternative approach to electric power generation on the surface of the moon. The raw materials for large-scale solar cell growth could be available from the waste products generated in regolith processing for volatiles collection and oxygen extraction. The production of vast areas of solar cells can be implemented through a self-generation process whereby the power generated by grown cells is used to produce more cells.

Ignatiev, Alex↗
NASA NTRS1992

First steps to lunar manufacturing: Results of the 1988 Space Studies Institute Lunar Systems Workshop

Prior studies by NASA and the Space Studies Institute have looked at the infrastructure required for the construction of solar power satellites (SPS) and other valuable large space systems from lunar materials. This paper discusses the results of a Lunar Systems Workshop conducted in January 1988. The workshop identified components of the infrastructure that could be implemented in the near future to create a revenue stream. These revenues could then be used to 'bootstrap' the additional elements required to begin the commercial use of nonterrestrial materials.

Maryniak, Gregg E.↗
NASA NTRS1992

Estimating Lunar Pyroclastic Deposit Depth from Imaging Radar Data: Applications to Lunar Resource Assessment

Lunar pyroclastic deposits represent one of the primary anticipated sources of raw materials for future human settlements. These deposits are fine-grained volcanic debris layers produced by explosive volcanism contemporaneous with the early stage of mare infilling. There are several large regional pyroclastic units on the Moon (for example, the Aristarchus Plateau, Rima Bode, and Sulpicius Gallus formations), and numerous localized examples, which often occur as dark-halo deposits around endogenic craters (such as in the floor of Alphonsus Crater). Several regional pyroclastic deposits were studied with spectral reflectance techniques: the Aristarchus Plateau materials were found to be a relatively homogeneous blanket of iron-rich glasses. One such deposit was sampled at the Apollo 17 landing site, and was found to have ferrous oxide and titanium dioxide contents of 12 percent and 5 percent, respectively. While the areal extent of these deposits is relatively well defined from orbital photographs, their depths have been constrained only by a few studies of partially filled impact craters and by imaging radar data. A model for radar backscatter from mantled units applicable to both 70-cm and 12.6-cm wavelength radar data is presented. Depth estimates from such radar observations may be useful in planning future utilization of lunar pyroclastic deposits.

Campbell, B. A.↗
NASA NTRS1992

Power transmission by laser beam from lunar-synchronous satellites to a lunar rover

This study addresses the possibility of beaming laser power from synchronous lunar orbits (L1 and L2 LaGrange points) to a manned long-range lunar rover. The rover and two versions of a satellite system (one powered by a nuclear reactor; the other by photovoltaics) are described in terms of their masses, geometry, power needs, mission and technological capabilities. Laser beam power is generated by a laser diode array in the satellite and converted to 30 kW of electrical power at the rover. Present technological capabilities, with some extrapolation to near future capabilities, are used in the descriptions. The advantages of the two satellite/rover systems over other such systems and over rovers with on-board power are discussed along with the possibility of enabling other missions.

Williams, M. D.↗
NASA NTRS1995

The Lunar Ultraviolet Telescope Experiment (LUTE): Enabling technology for an early lunar surface payload

The Lunar Ultraviolet Telescope Experiment (LUTE) is a 1-m aperture, fixed declination, optical telescope to be operated on the surface of the Moon. This autonomous science payload will provide an unprecedented ultraviolet stellar survey even before manned lunar missions are resumed. This paper very briefly summarizes the LUTE concept analyzed by the LUTE Task Team of NASA's Marshall Space Flight Center (MSFC). Scientific capabilities and the Reference Design Concept are identified, and the expected system characteristics are summarized. Technologies which will be required to enable the early development, deployment, and operation of the LUTE are identified, and the principle goals and approaches for their advancement are described.

Nein, M. E.↗