Cosmic-ray and gas-retention ages of the Chassigny meteorite
Cosmic radiation and gas retention ages of Chassigny achondrite by measuring Al, K and noble gases contents and production rates in meteorites
Lancet, K.↗
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Ar 40/Ar 39 ages from Fra Mauro
Apollo 14 Fra Mauro rock fragment samples, determining Ar 40/Ar 39 ages
Husain, L.↗
Potassium-argon ages of the Manicouagan- Mushalagan Lakes structure
Potassium-argon age determination for shock- metamorphosed anorthosites of Manicouagan- Mushalagan Lakes structure
Wolfe, S. H.↗
Ages of lunar mare surfaces
Near side lunar mare surfaces ages interpretation in terms of geomorphic indices based on crater number density
Ronca, L. B.↗
Ages of coexisting minerals from heat-flow borehole sites, central Sierra Nevada batholith
Fission track and K-Ar ages of coexisting minerals in drill core from heat-flow boreholes in western central Sierra Nevada batholith
Dodge, F. C. W.↗
Ages of crystalline rocks from Fra Mauro
Apollo 14 flight Fra Mauro crystalline rocks age measurement, using Ar 40/39 ratio method
Husain, L.↗
Kr super 81-Kr and K-Ar super 40 ages, cosmic-ray spallation products, and neutron effects in lunar samples from Oceanus Procellarum
Cosmic ray exposure ages and rare gas concentration profiles in Apollo 12 lunar rocks, discussing spallation products and neutron capture effects
Lugmair, G. W.↗
Cosmogenic radionuclide concentrations and exposure ages of lunar samples from Apollo 12
Cosmogenic radionuclide concentration and exposure ages of Apollo 12 rock from Ocean of Storms
Bell, P. R.↗
Rubidium-strontium and potassium-argon age of lunar sample 15555.
The lunar mare basalt 15555 from the edge of Hadley Rille has been dated at 3.3 b.y. by both rubidium-strontium and potassium-argon techniques. Age and trace element abundances closely resemble those of the Apollo 12 mare basalts. Data from lunar basalts obtained thus far indicate that they cannot be derived by simple fractionation from a homogeneous source.
Murthy, V. R.↗
Gas-retention and cosmic-ray exposure ages of lunar rock 15555.
Conclusions are presented regarding the age of formation and exposure to cosmic rays of rock 15555 (a large rock from near the rim of Hadley Rille presumed to be a fragment of the local bedrock), based on isotopic dilution K/Ar and Ar-40/Ar-39 methods. Comparisons are made with other investigators' findings, and some cases of agreement and divergence are discussed.
Podosek, F. A.↗
Age of a lunar anorthosite.
The crystallization age of an Apollo 15 anorthosite rock, 15415,9, returned from the lunar highlands has been measured to be 4.09 (plus or minus 0.19) b.y. The primitive lunar crust must have been formed in the first 300 to 400 m.y. The results give some credence to the hypothesis that the primitive lunar surface was molten and large-scale fractional crystallization occurred in the early history of the moon.
Husain, L.↗
Descartes region - Evidence for Copernican-age volcanism.
A model that suggests that the high-albedo central region of the Descartes Formation was formed by Copernican-age volcanism was developed from Orbiter photography, Apollo 12 multispectral photography, earth-based spectrophotometry, and thermal IR and radar data. The bright surface either is abundant in centimeter-sized rocks or is formed from an insulating debris layer overlying a surface with an abundance of rocks in the 1- to 20-cm size range. On the basis of these data, the bright unit is thought to be a young pyroclastic deposit mantling older volcanic units of the Descartes Formation. Since the Apollo 16 target point is only 50 km NW of the central part of this unit, evidence for material associated with this unique highland formation should be searched for in returned soil and rock samples.
Head, J. W., III↗
Experiences with physical conditioning programs in middle-aged men
Long term effects of physical exercise and conditioning in the prevention and treatment of coronary heart disease are studied. Some aspects of the problem are outlined and difficulties encountered in a group of middle aged business executives using a carefully prescribed, but non-regimented and loosely supervised conditioning program employing commonly used forms of exercise (bicycling and jogging), are described.
Schuster, B.↗
Techniques for lithium removal from 1040 C aged tantalum alloy, T-111
The liquid ammonia and vacuum distillation techniques were found to be satisfactory for removing lithium from 1040 C aged T-111 (tantalum - 8-percent tungsten- 2-percent hafnium). Results of ductility tests and chemical analysis show that these two methods are adequate for removing lithium without embrittlement or contamination of the T-111. Moist air exposure of T-111 with traces of lithium on the surface produced mixed results. Some specimens were ductile; others were brittle. Brittle T-111 had an increased hydrogen content. Water removal of lithium from T-111 caused brittleness and an increased hydrogen concentration.
Gahn, R. F.↗
Space age management for social problems
Attempts to apply space age management to social problems were plagued with difficulties. Recent experience in the State of Delaware and in New York City, however, indicate new possibilities. Project management as practiced in NASA was applied with promising results in programs dealing with housing and social services. Such applications are feasible, according to recent research, because project management utilizes social and behavioral approaches, as well as advanced management tools, such as PERT, to achieve results.
Levine, A. L.↗
Effects of sudden mixing in the solar core on solar neutrinos and ice ages.
Some numerical experiments with a solar model have been conducted in connection with the hypothesis regarding the effects of mixing in the solar core. Questions concerning a plausible mechanism by which such a mixing could be produced are explored. The variation of solar luminosity throughout the numerical experiments is shown. In connection with a great change in luminosity after a second mixing, it is suggested that the earth is presently undergoing an ice age.
Ezer, D.↗
Apollo 14 and 15 samples - Rb-Sr ages, trace elements, and lunar evolution.
Studies concerning Rb-Sr isotopic relations are discussed together with abundance measurements regarding K, Rb, Sr, and Ba in Apollo 14 and 15 rocks and soils. The studies include age determination by the internal isochron technique on one basaltic rock sample from each of the two missions. In addition, total sample measurements have been made on samples of fines material from both missions. Trace element abundances and Rb-Sr systematics in the various grain size fractions of three of the fines have also been analyzed.
Murthy, V. R.↗
Re-187, recycling r-process elements through stars, and the age of the Galaxy.
The enhanced beta-decay rate of ionized Re-187 in stars has been studied within the context of a detailed numerical model of the production of r-process elements and their recycling through stars during the course of galactic evolution. It is concluded that the enhanced decay rate does not significantly reduce the Re-Os chronometer age for the Galaxy. Consequently, the Re-187 beta-decay half-life and the Os-186/Os-187 neutron cross-section ratio remain as the significant uncertainties in this chronology. Unlike the uncertainties in other chronologies, both are amenable to laboratory measurements.
Talbot, R. J., Jr.↗