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Hostetler, C. J.

Publications and source records attributed to Hostetler, C. J..

4 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1982

A possible common origin for the rare gases on Venus, earth, and Mars

The rare gas concentrations in the terrestrial planets and the carbonaceous chondrites could have been derived from a single source an early solar wind. The fractionation processes responsible for the varying concentration patterns in this model are differential ionization and the relative separation of neutrals from ions due to interaction with the solar magnetic field. If species dependent effects are small relative to radius dependent effects, this process can explain in detail both the relative and absolute abundances in the terrestrial planets and carbonaceous chondrites. The electron temperatures predicted by the data are consistent with astrophysical constraints previously derived for the solar nebula, and the timeline of events necessary for this model is consistent with accretion in a gas free environment. If species dependent fractionations are small, or approximately cancel each other, the earth is found to be outgassed by an order of magnitude more efficiently than Venus or Mars.

Hostetler, C. J.↗
NASA NTRS1980

Predicting major element mineral/melt equilibria - A statistical approach

Empirical equations have been developed for calculating the mole fractions of NaO0.5, MgO, AlO1.5, SiO2, KO0.5, CaO, TiO2, and FeO in a solid phase of initially unknown identity given only the composition of the coexisting silicate melt. The approach involves a linear multivariate regression analysis in which solid composition is expressed as a Taylor series expansion of the liquid compositions. An internally consistent precision of approximately 0.94 is obtained, that is, the nature of the liquidus phase in the input data set can be correctly predicted for approximately 94% of the entries. The composition of the liquidus phase may be calculated to better than 5 mol % absolute. An important feature of this 'generalized solid' model is its reversibility; that is, the dependent and independent variables in the linear multivariate regression may be inverted to permit prediction of the composition of a silicate liquid produced by equilibrium partial melting of a polymineralic source assemblage.

Hostetler, C. J.↗
NASA NTRS1980

On the early global melting of the terrestrial planets

Attention is given to all the mechanisms currently known which might have been responsible for the melting of the moon. A comparison is conducted of the terrestrial planets and the moon, taking into account the conditions in the early solar system as a function of time. The assumption is made that the terrestrial planets and the moon all reached sizes comparable to their present sizes at the same time, so that the same heating mechanisms were operating on all of the bodies when their early crusts were formed. A chronology of the early solar system is established in order to evaluate the time periods during which each of the mechanisms might have been active. If the moon and planets formed within 2,000,000 years after the formation of the protosun, the conclusion appears inescapable that all of the terrestrial planets melted.

Hostetler, C. J.↗