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Martian Atmospheric Erosion Rates
Science, 2007Mars was once wet but is now dry, and the fate of its ancient carbon dioxide atmosphere is one of the biggest puzzles in martian planetology. We have measured the current loss rate due to the solar wind interaction for different species: Q(O + ) = 1.6·10 23 per second = 4 grams per second (g ...
Stas, Barabash +3 more
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Isotopic Composition of the Martian Atmosphere
Science, 1976Results from the neutral mass spectrometer carried on the aeroshell of Viking 1 show evidence for NO in the upper atmosphere of Mars and indicate that the isotopic composition of carbon and oxygen is similar to that of Earth. Mars is enriched in 15 N relative to Earth by about 75 percent, a consequence of escape ...
Nier, Alfred O. +2 more
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CO2 solubility in Martian basalts and Martian atmospheric evolution
Geochimica et Cosmochimica Acta, 2011Abstract To understand possible volcanogenic fluxes of CO 2 to the Martian atmosphere, we investigated experimentally carbonate solubility in a synthetic melt based on the Adirondack-class Humphrey basalt at 1–2.5 GPa and 1400–1625 °C. Starting materials included both oxidized and reduced compositions, allowing a test of the effect of iron oxidation
Ben D. Stanley +2 more
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Disentangling xenon components in Nakhla: martian atmosphere, spallation and martian interior
Geochimica et Cosmochimica Acta, 2001A powdered sample of Nakhla was separated into 3 subsamples. One was left otherwise untreated, one was washed in water and one etched with HNO3 removing 6% of the original mass. We report results of isotopic analysis of xenon released by laser step heating on aliquots of each of these subsamples; some aliquots were neutron irradiated before isotopic ...
Gilmour, J. D. +2 more
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Atmospheric maneuvering during Martian entry
15th Atmospheric Flight Mechanics Conference, 1988A comparative-advantages study is made of two different Martian atmospheric entry maneuvers, on the basis of calculation results for the case of a vehicle with a maximum L/D ratio of 2.3. Entries from a highly elliptical Martian orbit at 5 km/sec are more difficult than those from a lower altitude and speed orbit at 3.5 km/sec, due to their more ...
MICHAEL TAUBER +2 more
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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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