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Atmosphere of Mars: Mariner IV Models Compared
Science, 1966Three classes of models for the atmosphere of Mars differ in identifying the main ionospheric layer measured by Mariner IV as being analogous to a terrestrial F 2 , F 1 , or E layer. At an altitude of several hundred kilometers, the relative atmospheric mass densities for these models (in the
G, Fjeldbo, W C, Fjeldbo, V R, Eshleman
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High-Temperature Thermodynamic Properties of Mars-Atmosphere Components
Journal of Spacecraft and Rockets, 2004Methods of calculation of high-temperature thermodynamic properties for some selected Mars-atmosphere components in the temperature range from 200 to 50.000 K and results are discussed and compared with previous works. Aspects such as quasi-bound rotational states, cutoff criteria, and autoionizing states are considered.
M Capitelli +8 more
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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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Impact erosion of the primordial atmosphere of Mars
Nature, 1989Abundant geomorphic evidence for fluvial processes on the surface of Mars suggests that during the era of heavy bombardment, Mars's atmospheric pressure was high enough for liquid water to flow on the surface. Many authors have proposed mechanisms by which Mars could have lost (or sequestered) an earlier, thicker atmosphere but none of these proposals
H J, Melosh, A M, Vickery
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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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Detection of Methane in the Atmosphere of Mars
Science, 2004We report a detection of methane in the martian atmosphere by the Planetary Fourier Spectrometer onboard the Mars Express spacecraft. The global average methane mixing ratio is found to be 10 ± 5 parts per billion by volume (ppbv). However, the mixing ratio varies between 0 and 30 ppbv over the planet.
Formisano, Vittorio +4 more
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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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Most of Mars' atmosphere has been lost
Science, 2017Martian Atmosphere Mars has a thin atmosphere composed mainly of carbon dioxide. Evidence on the planet's surface indicates that Mars was once warmer and wetter, suggesting a thicker atmosphere in the past. Jakosky et al. measured the abundances of argon isotopes at different heights in the atmosphere.
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Oblateness of the atmosphere of Mars
Nature, 1976ON April 8, 1976 Mars occulted the bright star ɛ Geminorum (magnitude 3.2). Predictions1 were issued well in advance since such occurrences are very rare: indeed, it is estimated that Mars occults a star as bright as this about once in 500 yr. Accurate observations of the duration of the occultation were made from four sites on the Earth and these are ...
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Abstracts of the Papers Printed in the Philosophical Transactions of the Royal Society of London
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 whilst by the latter the ...
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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 whilst by the latter the ...
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