The experiments of Biosatellite II
Biosatellite 2 onboard experiments studying weightlessness effects on biological processes and interaction with radiation from Sr 85 gamma ray source
Deserres, F. J.↗
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The gamma ray experiment for the Small Astronomy Satellite B (SAS-B)
A magnetic core digitized spark chamber gamma ray telescope has been developed for satellite use. The detector has the following characteristics: effective area = 500 cu/cm, solid angle = 1/4 SR; efficiency (high energy) = 0.29; and time resolution of better than two milliseconds.
Fichtel, C. E.↗
NASA-EPA automotive thermal reactor technology program
The status of the NASA-EPA automotive thermal reactor technology program is summarized. This program is concerned primarily with materials evaluation, reactor design, and combustion kinetics. From engine dynamometer tests of candidate metals and coatings, two ferritic iron alloys (GE 1541 and Armco 18-SR) and a nickel-base alloy (Inconel 601) offer promise for reactor use. None of the coatings evaluated warrant further consideration. Development studies on a ceramic thermal reactor appear promising based on initial vehicle road tests. A chemical kinetic study has shown that gas temperatures of at least 900 K to 1000 K are required for the effective cleanup of carbon monoxide and hydrocarbons, but that higher temperatures require shorter combustion times and thus may permit smaller reactors.
Blankenship, C. P.↗
Information management system study results. Volume 1: IMS study results
The information management system (IMS) special emphasis task was performed as an adjunct to the modular space station study, with the objective of providing extended depth of analysis and design in selected key areas of the information management system. Specific objectives included: (1) in-depth studies of IMS requirements and design approaches; (2) design and fabricate breadboard hardware for demonstration and verification of design concepts; (3) provide a technological base to identify potential design problems and influence long range planning (4) develop hardware and techniques to permit long duration, low cost, manned space operations; (5) support SR&T areas where techniques or equipment are considered inadequate; and (6) permit an overall understanding of the IMS as an integrated component of the space station.
Source record↗
A space qualified radiation source holder
A radiation source holder was developed to permit controlled exposure of biological material to a gamma-emitting radiation source during flight in a recoverable earth-orbiting satellite. A unique spring drive mechanism, activated by real time commands from the ground station, moved the Sr-85 source from a shielded position to the exposed position and then back to the shielded condition before reentry and recovery. A fail-safe feature utilized the reentry deceleration force to ensure that the source would be in a shielded position during the recovery operations. The device was successfully flown on Biosatellite 2.
Polaski, L. J.↗
Application of satellite infrared measurements to mapping sea ice
The application of the ITOS-SR (scanning radiometer) infrared measurements for mapping sea ice was examined. The work included detailed mapping of ice features visible in the ITOS nighttime DRSR (direct readout scanning radiometer) pictorial data and in Nimbus summertime film strip data. Analyses of digital temperature values from computer printouts of ITOS stored data and from Nimbus data listings were also undertaken, and densitometric measurements of both ITOS and Nimbus data were initiated.
Barnes, J. C.↗
Ultraviolet observations of weak-helium stars
Ultraviolet filter photometry aboard OAO-2 has been carried out for the weak helium stars 3 Cen A, 3 Sco, HD 144334, HD 21699, HD 144844, alpha Scl, HR 8535, HR 8770 and HD 144661. The flux distribution is compared with that of B3 to B8 main sequence and giant stars in terms of color-color diagrams. When allowance is made for line blocking shortward of 2800 A that most of the weak helium stars have normal fluxes in good agreement with their ground-based colors. The star alpha Scl is a light and spectrum variable. The strengthening of Ti II and Sr II lines around 2400 A appears to redistribute flux longward of the Balmer discontinuity. The flux distribution indicates an effective temperature about 1500 K higher than previously determined.
Bernacca, P. L.↗
Geochemical aspects of some Japanese lavas.
K, Rb, Sr, Ba and rare-earth concentrations in some Japanese lavas have been determined by mass-spectrometric stable-isotope dilution. The samples fall into three rare-earth groups corresponding to tholeiitic, high alumina and alkali basalts. Japanese tholeiites have trace element characteristics similar to those of oceanic ridge tholeiites except for distinctly higher relative concentrations of Ba. Japanese lavas may result from various degrees of partial fusion of amphibole eclogite.
Philpotts, J. A.↗
Uranium-bearing minerals of lunar rock 12013.
The U distribution in rock 12013 was studied by fission track and elemental mapping techniques. Major U-bearing phases are whitlockite, apatite, zircon, and phase beta, which is a Zr-Ti mineral rich in Fe, Nb, Y, REE, and containing up to 3.6% UO2, 4.7% ThO2 and 4.2% PbO. Calculated microprobe ages for phase beta average 4.0 b.y. and are in reasonable agreement with Rb-Sr and K-Ar ages. Phase beta plays a significant role in the U-Th-Pb systematics of rock 12012 and may play a similar role in the model ages of lunar soil.
Haines, E. L.↗
Mineralogy, petrology, and chemistry of a Luna 16 basaltic fragment, sample B-1.
Petrological, mineralogical, and chemical investigations of the B-1 Luna 16 sample have revealed that the sample is a fine-grained ophitic basalt which is distinguished from the Apollo samples by containing a single pyroxene, an ilmenite content intermediate to that of the Apollo samples, and subequal amounts of pyroxene and plagioclase. It is also distinguished by a high Sr content and a high K/U value.
Albee, A. L.↗
Some chemical features of basalts from the British Tertiary Province.
An attempt has been made to chemically characterize the basalts from four islands, Rhum, Eigg, Canna, and Muck that, together with Skye, comprise the Inner Hebrides. The basalts are shown to be chemically distinct from tertiary basalts described from the Faroes and Iceland, but have the low concentrations of Rb, Sr found in some mildly alkaline basalts dredged from the Atlantic. Possible evolution of these rocks is discussed.
Ridley, W. I.↗
U, Th, Pb and REE abundances and Pb 207/Pb 206 ages of individual minerals in returned lunar material by ion microprobe mass analysis.
Results of ion microprobe analyses of Apollo 11, 12 and 14 material, showing that U, Th, Pb and REE are concentrated in accessory minerals such as apatite, whitlockite, zircon, baddeleyite, zirkelite, and tranquillityite. Th/U ratios are found to vary by over a factor of 40 in these minerals. K, Ba, Rb and Sr have been localized in a K rich, U and Th poor glass phase that is commonly associated with the U and Th bearing accessory minerals. Li is observed to be fairly evenly distributed between the various accessory phases. The phosphates have been found to have REE abundance patterns (normalized to the chondrite abundances) that are fairly flat, while the Zr bearing minerals have patterns that rise steeply, by factors of ten or more, from La to Gd. All the accessory minerals have large negative Eu anomalies. Radiometric age dates (Pb 207/Pb 206) of the individual U and Th bearing minerals compare favorably with the Pb 207/Pb 206 age of the bulk rocks.
Andersen, C. A.↗
Diffusion in the system K2O-SrO-SiO2. II - Cation self-diffusion coefficients.
The self-diffusion coefficients were measured by introducing a slab of glass previously irradiated in a reactor between two slabs of unirradiated glass. By heating the specimens, etching them sequentially and determining the radioactivity, self-diffusion coefficients for K and Sr were measured. It is pointed out that the results obtained in the investigations appear to support the proposal that the network of the base glass predominantly controls the activation energy for the diffusion of ions.
Varshneya, A. K.↗
Shock melting and vaporization of metals.
The effect of initial porosity on shock induction of melting and vaporization is investigated for Ba, Sr, Li, Fe, Al, U, and Th. For the less compressible of these metals, it is found that for a given strong shock-generation system (explosive in contact, or flyer-plate impact) an optimum initial specific volume exists such that the total entropy production, and hence the amount of metal liquid or vapor, is a maximum. Initial volumes from 1.4 to 2.0 times crystal volumes, depending on the metal sample and shock-inducing system, will result in optimum post-shock entropies.
Ahrens, T. J.↗
U-Th-Pb systematics in three Apollo 14 basalts and the problem of initial Pb in lunar rocks.
The isotopic composition of Pb and the elemental concentration of U, Th and Pb were measured on 'total' rock samples 14053, 14073 and 14310 and on mineral separates of 14310 and 14053. These are the first Pb-U isochrons obtained for lunar basalts and indicate a reasonable solution to the previous discrepancy between the different methods of 'absolute' age determination. The resulting U-Pb isochron ages are compatible with the Rb-Sr and K-Ar ages on the same rocks. However, it is not possible to establish a precise time of 'crystallization' from the Pb-U data because of the small angle of intersection between the linear arrays and the concordia curve. These data show that total rock model ages do not in general yield crystallization ages. The data on 14310 and 14053 show that these rocks were formed containing a highly radiogenic initial lead which accounts for the excessively high total rock model ages by the U-Th-Pb method. The data prove that at the time of extrusion of some basalts, unsupported lead with extremely high Pb-207/Pb-206 ratios was added to the lunar surface.
Tera, F.↗
Development of lithium doped radiation resistent solar cells
Lithium-doped solar cells have been fabricated with initial lot efficiencies averaging 11.9 percent in an air mass zero (AMO) solar simulator and a maximum observed efficiency of 12.8 percent. The best lithium-doped solar cells are approximately 15 percent higher in maximum power than state-of-the-art n-p cells after moderate to high fluences of 1-MeV electrons and after 6-7 months exposure to low flux irradiation by a Sr-90 beta source, which approximates the electron spectrum and flux associated with near Earth space. Furthermore, lithium-doped cells were found to degrade at a rate only one tenth that of state-of-the-art n-p cells under 28-MeV electron irradiation. Excellent progress has been made in quantitative predictions of post-irradiation current-voltage characteristics as a function of cell design by means of capacitance-voltage measurements, and this information has been used to achieve further improvements in lithium-doped cell design.
Berman, P. A.↗
Determination of the total outgoing radiance of the earth-atmosphere system
Utilizing eighty atmospheric models, the equivalent black body temperatures for the 6-7, 10-11, 15-16 and the 20-24 micron spectral regions, corresponding to the Nimbus 3 medium resolution infrared radiometer were computed. The black body temperatures for the 5-30 micron channel and the total outgoing radiances for these atmospheres were also computed. It was found that the total radiation can be estimated from the 10-11 micron channel alone with a standard error of 2.2 watts/sq m sr.
Pasternak, M.↗
Relativistic heavy cosmic rays
During three balloon flights of a 1 sq m sr ionization chamber/Cerenkov counter detector system, measurements were made of the atmospheric attenuation, flux, and charge composition of cosmic ray nuclei with 16 is less than or = Z is less than or = 30 and rigidity greater than 4.5 GV. The attenuation mean free path in air of VH (20 less than or = Z less than or = 30) nuclei is found to be 19.7 + or - 1.6 g/sq cm, a value somewhat greater than the best previous measurement. The attenuation mean free path of iron is found to be 15.6 + or - 2.2 g/sq cm, consistent with predictions of geometric cross-section formulae. An absolute flux of VH nuclei 10 to 20% higher than earlier experiments at similar geomagnetic cutoff and level of solar activity was measured. The relative abundances of even-charged nuclei are found to be in good agreement with results of other recent high resolution counter experiments. The observed cosmic ray chemical composition implies relative abundances at the cosmic ray source of Ca/Fe = 0.12 + or - 0.04 and S/Fe = 0.14 + or - 0.05.
Mewaldt, R. A.↗