Lunar bases

Bugbee, B. G., Salisbury, F. B. (1989). Controlled environment crop production Hydroponic vs. lunar regolith. In D. W. Ming,D. L. Henninger (Eds.), Lunar Base Agriculture Soils for Plant Growth (pp. 107-129). Amer. Soc. Agronomy, Madison, WI, USA. 

In zero-gravity environments, human height increases by a few centimeters. This is because of the effects of reduced spinal curvature and the expansion of intervertebral discs in the back. The downside of this is lower back pain for astronauts. Lunar dust can pose pesky problems for astronauts working on the Moon. At sunrise and sunset, lunar dust tends to levitate and stick to surfaces. If lunar dust seeps into machinery, it can cause system failures, making this an important engineering concern for future lunar base builders. 

RAPID (Refuelling by All Pins, Integral Design) is the abbreviation for a small sodium cooled reactor of 10 000 kW(th) (1000 kW(e)) with U-Pu-Zr metal fuel and fast neutron spectrum [XVII-1 and XVII-2]. It is one of the successors of the RAPID-L [XVII-3 to XVII-7] - the operator-free fast reactor concept designed for a lunar based power system. 

In fiscal years 1999-2001, the Japan Atomic Energy Agency (IAEA) supported the RAPID-L project this predecessor of RAPED was designed for a lunar-based power system. 

The design and R D for the 200 kW(e) lithium cooled, uranium-nitride fuelled fast reactor RAPID-L, intended for a lunar-based power system, was also conducted by the CRIEPI. 

Occurrence and Recovery. Rhenium is one of the least abundant of the naturally occurring elements. Various estimates of its abundance in Earth s cmst have been made. The most widely quoted figure is 0.027 atoms pet 10 atoms of silicon (0.05 ppm by wt) (3). However, this number, based on analyses for the most common rocks, ie, granites and basalts, has a high uncertainty. The abundance of rhenium in stony meteorites has been found to be approximately the same value. An average abundance in siderites is 0.5 ppm. In lunar materials, Re, when compared to Re, appears to be enriched by 1.4% to as much as 29%, relative to the terrestrial abundance. This may result from a nuclear reaction sequence beginning with neutron capture by tungsten-186, followed by p-decay of of a half-hfe of 24 h (4) (see Extraterrestrial materials). 

HMX based expls for projects such as the 8" arty fired atomic proj and the Lunar seismic expts were evolved during the 1960 s and early 1970 s using Teflon as the binder (Refs 51, 55, 60, 67 69)... 

RBS is based on collisions between atomic nuclei, and it involves measuring the number and energy of ions in a beam which backscatter after colliding with atoms in the near-surface region of a sample. The use of scattering as an analysis tool led to the first in situ chemical analysis of the lunar surface during the landing of Surveyor V. The use of particle accelerators as an a-source was the next powerful step made in Chalk River (Canada) and Arus (Denmark). 

Studies Based on Isotope Production in Meteorites and on the Lunar Surface... 

Immature soil samples have S Te values that are indistinguishable from lunar rocks, whereas submature and mature soils have 5 Fe values that are greater than those of lunar rocks, and S Te values are positively correlated with Ig/FeO values (Fig. 12). Lunar regolith samples in general tend to have heavy isotopic compositions as compared to lunar rock samples, as demonstrated by isotopic analyses of O, Si, S, Mg, K, Ca, and Cd (Epstein and Taylor 1971 Clayton et al. 1974 Russell et al. 1977 Esat and Taylor 1992 Humayun and Clayton 1995 Sands et al. 2001 Thode 1976). The origin of isotopic compositions that are enriched in the heavy isotopes has been presumed to reflect sputtering by solar wind and vaporization, where preferential loss of the lighter isotope to space occurs. In contrast to previous isotopic studies, the Fe isotope compositions measured in the Lunar Soil Characterization Consortium samples can be related to a specific phase based on the positive correlation in Ig/FeO and 5 Fe values (Fig. 12). 

My mother s death was the first of these points in time that I isolated. Then I noted that my chance-formed relationship with Ev had begun sixty-four days after that, and that the culmination of the experiment at La Chorrera had occurred another sixty-four days later. The notion of a hexagram-based lunar year grew out of the idea of six cycles of sixty-four days each, a year of six parts, just as an / Ching hexagram has six lines. 

Taylor L.A., Onorato P.I., and Uhlmann D.R. (1977) Cooling rate estimations based on kinetic modeling of Fe-Mg diffusion in olivine. Proc. Lunar Sd. Conf. 8th, 1581-1592. 

Tera-Wasserburg diagram for lunar basalt 14053. The measured data define a discordia line that intersects the -axis at (207 /206 ), = 1.46. The slope of the line, based on two whole-rock samples and a magnetite separate, is -0.88366. The intersection of the discordia line with the concordia curve gives the age of the sample. After Faure and Mensing (2005). 

Summary of radiometric ages for lunar samples, based on a variety of isotope chronometers. 

A gross subdivision of the Moon s surface is based on albedo. The bright regions are the highlands, which are clearly ancient because of their high densities of impact craters. The dark regions are younger maria, basaltic lavas that flooded the impact basins on the nearside of the Moon. Mare basalts are exposed over 17% of the lunar surface and probably comprise only 1% of the crustal volume. 

Mare basalts include lavas that erupted from fissures and pyroclastic deposits that produced glass beads. Six of the nine missions to the Moon that returned samples included basalts. The mare basalts from different sites have distinctive compositions and are classified based on their Ti02 contents, and to a lesser extent on their potassium contents (Fig. 13.3). A further subdivision is sometimes made, based on A1203 contents. Mare basalts are compositionally more diverse than their terrestrial counterparts. Volcanic glass beads, formed by fire fountains of hot lava erupting into the lunar vacuum, were found at several Apollo sites and eventually were shown to be a constituent of virtually every lunar soil. The glasses are ultramafic in composition and formed at very high temperatures. 

Samples returned by the Apollo and Luna missions can be readily distinguished based on their contents of FeO and thorium. This may seem like an unlikely choice of chemical components for classification, but they nicely discriminate rock types and are easily measured by remote sensing. The FeO and thorium contents of ferroan anorthosites, mare basalts, impact melt breccias, and lunar meteorites are shown by various symbols in Figure 13.4. 

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