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Helium in the Martian atmosphere
Journal of Geophysical Research: Planets, 1993A simple two‐reservoir degassing model for the Earth decribes rather well the current degassing rate of 4He which is equal to (3±1)×106 cm −2s−1 according to data for the helium polar wind and the measured 3He/4He ratio. This value of the helium degassing and loss rate provides an important constraint in modeling of noble gases, and some recent models ...
Vladimir A. Krasnopolsky +2 more
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High-resolution Martian atmosphere modeling
Icarus, 1980A multilayer radiative transfer, high-spectral-resolution infrared model of the lower atmosphere of Mars has been constructed to assess the effect of scattering on line profiles. The model takes into accout aerosol scattering and absorption and includes a line-by-line treatment of scattering and absorption by CO2 and H2O. The aerosol complex indices of
W.G. Egan +3 more
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Icarus, 1966
Abstract The Martian atmosphere in its average condition is inactive and transparent to long-wave radiation. It is activated when moisture is supplied by the evaporation of the polar cap in spring time. As typical examples, the great yellow cloud in 1956, the Neith-Casius cloud, and the Propontis cloud are described.
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Abstract The Martian atmosphere in its average condition is inactive and transparent to long-wave radiation. It is activated when moisture is supplied by the evaporation of the polar cap in spring time. As typical examples, the great yellow cloud in 1956, the Neith-Casius cloud, and the Propontis cloud are described.
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The Martian atmosphere: Some unanswered questions
Journal of Molecular Evolution, 1979The study of the Martian atmosphere and its significance for the possible origin of life on Mars is still very incomplete. Further investigations are needed to define the total volatile inventory, the early history of the atmosphere, and the relationship of the atmosphere to the question of indigenous life.
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Photochemistry of the Martian atmosphere
Icarus, 1977A critical analysis is carried out for models which may be fine tuned to give agreement with observational constraints for O2, CO, and O3 in the Martian lower atmosphere and which are in accord also with upper atmospheric data for O and CO. The models have a number of features in common: dynamic mixing must be exceedingly rapid at heights above 90 km ...
T.Y. Kong, M.B. McElroy
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Photochemistry of HCl in the martian atmosphere
Icarus, 2022The recent discovery of HCl on Mars (Korablev et al. 2021, Olsen et al. 2021) indicates its strong seasonal variations and correlation with dust. To study this idea, we develop photochemical models for summer midlatitudes at aphelion and perihelion. We assume that HCl is formed in heterogeneous reactions of FeCl3 and/or NaCl in the dust with H, and the
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A Photochemical Model of the Martian Atmosphere
Icarus, 1994The factors governing the amounts of CO, O2, and O3 in the martian atmosphere are investigated using a minimally constrained, one-dimensional photochemical model. We find that the incorporation of temperature-dependent CO2 absorption cross sections leads to an enhancement in the water photolysis rate, increasing the abundance of OH radicals to the ...
Nair, Hari +4 more
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Meteoric ion layers in the Martian atmosphere
Faraday Discussions, 2010Low-lying plasma layers have been observed sporadically in the Martian atmosphere by radio occultation measurements from spacecraft such as the Mars Express Orbiter and the Mars Global Surveyor. These layers are just a few km wide, and tend to occur around 90 km. It has been proposed that the layers consist of metallic ions, for two reasons: they occur
Charlotte L, Whalley, John M C, Plane
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Composition of the Martian atmosphere
Space Science Reviews, 1991Data on the composition of the Martian atmosphere obtained by instruments aboard the Viking spacecraft are not of sufficient accuracy to address important questions regarding the composition and history of Mars. Laboratory analyses of gases trapped in glassy phases of shergottite meteorite EETA 79001 yield precise data, but it remains to be ascertained
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Atmospheric effects on Martian aerocapture
17th Atmospheric Flight Mechanics Conference, 1990A preliminary study of the effects of the atmosphere on Martian aerocapture has been completed at NASA-Johnson. Nominal cases were defined and several types of density dispersions utilized to show the effect of L/D ratio on aerocapture performance. Both open and closed loop three-degree-of-freedom simulations were developed.
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