Primordial variations in the cosmic abundance of helium
Spatial variations in cosmic He abundance attributed to primordial temperature fluctuations at early epochs in Friedmann universe
Shapiro, S. L.↗
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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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How well do we know 'cosmic' abundances
Cl chondrites approximating primordial solar system matter condensable fractions based on isotopic/elemental abundance continuity, fractionation patterns and chondrules absence
Anders, E.↗
Carbon and nitrogen abundances in selected achondrites
Carbon and nitrogen abundances in howardites, enstatite and hypersthene achondrites
Gibson, E. K., Jr.↗
Limiting He 3 abundances in four H II regions
Limiting He 3 abundances in four H II regions
Goldwire, H. C., Jr.↗
Reduced helium abundances in nebulae
Reduced nebular helium abundances, using capture- cascade and collisional excitation calculations
Cox, D. P.↗
Elemental abundances of lunar soil and rocks from Apollo 12
Apollo 12 lunar soil, breccia and igneous rock samples, determining elemental abundances with spark source mass spectrometry and neutron activation analysis
Burdo, R. A.↗
Major element abundances in Apollo 12 rocks and fines by 14 MeV neutron activation
Apollo 12 lunar rocks and fines under high energy neutron activation analysis, determining O, Si, Al, Mg and Fe abundances
Ehmann, W. D.↗
Abundances of the 14 rare-earth elements and 12 other trace elements in Apollo 12 samples - Five igneous and one breccia rocks and four soils
Rare earth elements and trace elements abundance in Apollo 12 igneous rocks, breccia and lunar soil
Rey, P.↗
Total carbon and nitrogen abundances in Apollo 12 lunar samples
Apollo 12 samples total C and N abundances suggesting indigenous lunar material with solar wind component
Delles, F. M.↗
Isotopic abundances of actinide elements in Apollo 12 samples
Isotopic abundances and composition of U and Th in Apollo 12 soil and breccia samples, using mass spectroscopy
Diamond, H.↗
Concentrations and isotopic abundances of the rare gases in lunar matter
Rare gas concentrations and isotopic abundances in lunar rocks, fines and breccias from Apollo 11 and 12 flights, determining exposure and gas retention ages
Hintenberger, H.↗
Abundances and distribution of organogenic elements and compounds in Apollo 12 lunar samples
Organogenic elements and compounds abundances and distribution in Apollo 12 fines
Flory, D. A.↗
On the abundance of calcium in the solar corona
Calcium abundance in solar corona, using measured values for total intensity of continuum and integrated intensities ratio
Fisher, R. R.↗
The cosmic helium abundance
Cosmic helium abundance was studied through the interior structure of young stars, profiles of helium absorption lines in the photospheric spectra of hot young stars, and emission-line spectrum of ionized gas. It is concluded that helium occurred before galaxies were formed. Inconsistencies found in the quasar spectra are briefly mentioned.
Searle, L.↗
Origins of life II: Cosmic evolution, abundance, and distribution of biologically important elements; Proceedings of the Second Conference, Princeton, N.J., May 5-8, 1968.
Attention is given to important astronomical observations, the source of atmospheric hydrogen, and the primordial abundance of the elements. The evolution of the earth's atmosphere is discussed together with some physical facts about Venus and Mars. The likelihood that Mars produced an atmosphere in the past is investigated, taking into account present equilibria between the surface and the atmosphere, and the evidence regarding a past atmosphere.
Margulis, L.↗
Can astrophysical abundances be taken seriously.
The essential feature underlying abundance analysis is the assumption that local thermodynamic equilibrium prevails in a stellar atmosphere - i.e., that all relevant distribution functions, except that for the photons themselves, are thermal and determined by the local temperature. It is pointed out that the blanket assumption of local thermodynamic equilibrium in stellar atmospheres is a fundamental weakness. The assumption can only be valid if collisional processes are dominant in bringing about transitions between the excitation states of an atom. It has, however, been shown that the density in a stellar atmosphere is so low that, on the contrary, radiative processes are predominant.
Worrall, G.↗
Solar rare gases and the abundances of the elements.
Gas rich meteorites and lunar materials solar rare gases component observed and predicted relative abundance agreement indicating absence of fractionation in solar nebula formation
Marti, K.↗
RKR Franck-Condon factors for blue and ultraviolet transitions of some molecules of astrophysical interest and some comments on the interstellar abundance of CH, CH+ and SiH+.
RKR Franck-Condon factors for thirteen of the blue and ultraviolet transitions of AlF, AlO, BH, BD, CH, CD, CH(+), SiO and SiH(+) have been calculated. The interstellar abundances of CH, CH(+) and SiH(+) are discussed with regard to recent laboratory measurements, our Franck-Condon factors, and observations of the sun and the interstellar medium.
Liszt, H. S.↗