Isotopic composition of primordial helium in carbonaceous chondrites
Carbonaceous chondrites primordial He and Ne isotopes variations
Anders, E.↗
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Origin and development of optical activity of organic compounds on the primordial earth
Optically active organic compounds origin on primordial earth, emphasizing role of asymmetric catalyst
Harada, K.↗
Primordial radionuclide abundances, solar proton and cosmic-ray effects and ages of Apollo 11 lunar samples by non-destructive gamma ray spectrometry
Apollo 11 lunar rock and fines primordial radionuclide abundances and concentration gradients by gamma ray spectrometry at Lunar Receiving Laboratory
Bell, P. R.↗
Cosmogenic and primordial radionuclide measurements in Apollo 11 lunar samples by nondestructive analysis
Cosmogenic and primordial radionuclides in Apollo 11 lunar soil and rocks, using nondestructive gamma ray spectral measurements
Cooper, J. A.↗
Primordial accretion - Inferences from the lunar surface
Lunar rocks primordial accretion, examining ablation and transport of solids, liquid and vapor on surfaces
Arrhenius, G.↗
Primordial noble gases in separated meteoritic minerals. I
Primordial trapped planetary noble gases and solar isotopic ratios in separated meteoritic minerals from Orgueil carbonaceous chondrite
Anders, E.↗
Concerning the primordial abundance of helium in quasi-stellar sources
Quasars primordial He abundance, discussing relation to galactic evolution
Silk, J.↗
Aspects of the condensation of primordial silicates
Mafic silicates condensation in primordial solar nebula, explaining meteoritic abundance patterns by two component elemental volatility model and trace element distribution
Kerridge, J. F.↗
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.↗
Primordial oil slick
Methane atmosphere polymerization by solar UV to form primordial oil slick, discussing importance to life development
Dwyer, M. J.↗
Abundances of the primordial radionuclides K, Th, and U in Apollo 12 lunar samples by nondestructive gamma-ray spectrometry - Implications for origin of lunar soils
Primordial radionuclides K, Th and U concentrations in Apollo 12 lunar rocks, breccias and fines, using gamma ray spectrometry
Bell, P. R.↗
Erosion and mixing of the lunar surface from cosmogenic and primordial radionuclide measurements in Apollo 12 lunar samples
Lunar surface erosion and mixing from cosmogenic and primordial radionuclide measurement in Apollo 12 lunar rock and soil samples
Felix, W. D.↗
Some cosmogenic and primordial radionuclides in Apollo 12 lunar surface materials
Cosmogenic and primordial radionuclides in Apollo 12 surface rocks and fines from nondestructive gamma ray spectrometry
Wrigley, R. C.↗
The primordial sequence, ribosomes, and the genetic code.
Experimental investigation of the key question of the origin of life concerning the chronological order in the primordial sequence of nucleic acid, protein, and cell. It is pointed out that, when viewed against the background of experiments on the selective reaction of basic homopolyamine acids with mononucleotides (Lacey and Pruitt, 1969; Woese, 1968), the experiments made help to establish a basis for understanding how information originally flowed from proteins to nucleic acids.
Fox, S. W.↗
Some implications of a new value for the primordial solar deuterium-hydrogen ratio.
Some astrophysical implications of a primordial solar D/H ratio of 0.000015 are investigated. Perhaps the most interesting aspects of the D/H ratio concern galactic evolution and cosmology. It is shown that the initial galactic abundance of deuterium exceeds by at least a factor of 30 the abundance expected from known galactic production mechanisms. If a Friedmann cosmology is a correct description of the universe, it must be an open one unless some as yet unknown mechanism is invo ked to produce deuterium and He-3.
Black, D. C.↗
Primordial radioelements and cosmogenic radionuclides in lunar samples from Apollo 15.
Two basalts, two breccias, and two soils from Apollo 15 were analyzed by nondestructive gamma-ray spectrometry. The concentrations of potassium, thorium, and uranium in the basalts were similar to those in the Apollo 12 basalts, but the potassium:uranium ratios were somewhat higher. Primordial radioelements were enriched in the soils and breccia, consistent with a two-component mixture of mare basalt and up to 20 percent foreign component (KREEP). The abundance patterns for cosmogenic radionuclides implied surface sampling for all specimens. The galactic cosmic-ray production rate of vanadium-48 was determined as 57 (plus or minus 11) disintegrations per minute per kilogram of iron. Cobalt-56 concentrations were used to estimate the intensity of the solar flare of January 25, 1971.
O'Kelley, G. D.↗
Origin of planetary primordial rare gas - The possible role of adsorption.
The degree of physical adsorption of Ne, Ar, Kr, and Xe on pulverized samples of the Allende meteorite at 113 K has been measured. The observed pattern of equilibrium enrichment of heavy rare gases over light on the pulverized meteorite surfaces relative to the gas phase is similar to the enrichment pattern exhibited by planetary primordial rare gas when compared with the composition of solar rare gas. Results indicate that, at 113 K, a total nebular pressure of from .01 to .001 atm would be required to explain the Ar, Kr, and Xe abundances in carbonaceous chondrites with an adsorption mechanism. This pressure estimate is compatible with the range of possible nebular pressures suggested by astrophysical arguments. However, the subsequent mechanism by which initially adsorbed gas might have been transferred into the interiors of grains cannot be identified at present.
Fanale, F. P.↗
Primordial turbulence and the formation of galaxies.
The development of turbulence at early epochs in a Friedmann universe is studied, giving primary attention to the density fluctuations generated by vortical turbulence. Aspects of turbulence theory in a cosmogonical context are discussed together with a theory of turbulence in an expanding universe. It is suggested that small-amplitude density fluctuations generated by primordial turbulence before decoupling, rather than by the onset of supersonic turbulence after decoupling, can best account for the formation of galaxies. On the other hand, the requisite amount of angular momentum per unit mass to account for the rotation of galaxies is well explained by the turbulence parameters.
Silk, J.↗