Results 211 to 220 of about 6,099 (263)
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Science, 1966
The thermal structure of the upper atmosphere of Mars has been theoretically investigated. The exospheric temperature, for a pure CO 2 model atmosphere, lies between 400° and 700°K. The origin of the Martian atmosphere is discussed in the light of these results.
S H, Gross, W E, McGovern, S I, Rasool
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The thermal structure of the upper atmosphere of Mars has been theoretically investigated. The exospheric temperature, for a pure CO 2 model atmosphere, lies between 400° and 700°K. The origin of the Martian atmosphere is discussed in the light of these results.
S H, Gross, W E, McGovern, S I, Rasool
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Science, 1965
The Martian ionospheric observations made by Mariner IV are interpreted in terms of an atmospheric model. The ion peak is identified as an F2 peak, that is, as a maximum whose profile is controlled by ambipolar diffusion. The principal features of the resulting atmospheric model are that the atmosphere consists mainly of carbon dioxide ...
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The Martian ionospheric observations made by Mariner IV are interpreted in terms of an atmospheric model. The ion peak is identified as an F2 peak, that is, as a maximum whose profile is controlled by ambipolar diffusion. The principal features of the resulting atmospheric model are that the atmosphere consists mainly of carbon dioxide ...
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Science, 1972
Photochemical reactions in the martian exosphere produce fast atoms of oxygen, carbon, and nitrogen and provide large escape fluxes of these elements. They appear to play a crucial role in the evolution of the martian atmosphere. The relative outgassing rates of H 2 O and CO 2 on Mars are ...
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Photochemical reactions in the martian exosphere produce fast atoms of oxygen, carbon, and nitrogen and provide large escape fluxes of these elements. They appear to play a crucial role in the evolution of the martian atmosphere. The relative outgassing rates of H 2 O and CO 2 on Mars are ...
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Measurements in the Atmosphere of Mars
Applied Optics, 1969The detailed definition of the key features of Mars' atmosphere from one or a few entries and landings is a challenging task involving a variety of measurements, taken during entry and after landing, and correlated with observations to be taken from orbiters and flyby missions.
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Heterogeneous chemistry in the atmosphere of Mars
Nature, 2008Hydrogen radicals are produced in the martian atmosphere by the photolysis of water vapour and subsequently initiate catalytic cycles that recycle carbon dioxide from its photolysis product carbon monoxide. These processes provide a qualitative explanation for the stability of the atmosphere of Mars, which contains 95 per cent carbon dioxide. Balancing
Lefèvre, Franck +8 more
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Abstracts of the Papers Printed in the Philosophical Transactions of the Royal Society of London
Abstract The author refers the origin of the hypothesis of the “Extensive Atmosphere of Mars” to the observations of Cassini and Rœner, made at Briare and Paris in the year 1672. By the former it would seem that a star of the fifth magnitude became invisible with a three-feet telescope when at a distance of six minutes from the planet
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Abstract The author refers the origin of the hypothesis of the “Extensive Atmosphere of Mars” to the observations of Cassini and Rœner, made at Briare and Paris in the year 1672. By the former it would seem that a star of the fifth magnitude became invisible with a three-feet telescope when at a distance of six minutes from the planet
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Annual Review of Earth and Planetary Sciences, 1974
The atmosphere of Mars is essentially a pure carbon dioxide atmosphere that contains a small and seasonably varying amount of water vapor. A number of minor constituents which arise from the interactions of solar radiation with water vapor and carbon dioxide include carbon monoxide, atomic oxygen, molecular oxygen, ozone, and atomic hydrogen.
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The atmosphere of Mars is essentially a pure carbon dioxide atmosphere that contains a small and seasonably varying amount of water vapor. A number of minor constituents which arise from the interactions of solar radiation with water vapor and carbon dioxide include carbon monoxide, atomic oxygen, molecular oxygen, ozone, and atomic hydrogen.
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2019
It is believed that Mars underwent drastic climate change, changing its environment from warm and wet to cold and dry. This gives rise to the idea that Mars may have hosted life in the past and, indeed, may do so even today. Atmospheric evolution is thus an important key to understanding the history of Martian habitability.
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It is believed that Mars underwent drastic climate change, changing its environment from warm and wet to cold and dry. This gives rise to the idea that Mars may have hosted life in the past and, indeed, may do so even today. Atmospheric evolution is thus an important key to understanding the history of Martian habitability.
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Upper Atmosphere and Ionosphere of Mars
Science, 1966It is argued that the single-layer ionosphere at 125 kilometers discovered in the Mariner IV occultation experiment is an F1 region coinciding with the ultraviolet photoionization peak. The CO 2 density there must be of the order of 10 11 molecules per cubic centimeter.
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1973
The main emphasis of this review will be on Martian aeronomy, here defined to be the interaction of solar UV radiation with the atmosphere of Mars. A general outline of contemporary knowledge of the chemical composition and of the thermal structure of the Martian atmosphere, necessary for aeronomical calculations, is given in Sections 2 and 3 ...
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The main emphasis of this review will be on Martian aeronomy, here defined to be the interaction of solar UV radiation with the atmosphere of Mars. A general outline of contemporary knowledge of the chemical composition and of the thermal structure of the Martian atmosphere, necessary for aeronomical calculations, is given in Sections 2 and 3 ...
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