Planetary Exploration, 1968-1975; Report of a Study by the Space Science Board, Washington, D.C., June 1968 (1968) / Chapter Skim
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Planetary Atmospheres
Planetary Atmospheres
Pages 19-26
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From page 19... ...
No theoretical model atmosphere that includes the boundary layer exists for Earth, but one is being developed for Mars. The low level diurnal jet has been treated as a minor feature of the Earth, but it is a planetary-scale phenomenon on Mars and is receiving increased attention.
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From page 20... ...
Differences, if they exist, in isotopic composition between planetary matter and terrestrial matter are probably most easily detectable in the rare gases; and all the gases from neon through xenon can probably be included in the search because background interference in mass spectrometer measurements tends to fall off more rapidly with increasing atomic mass than does the abundance of the rare gases. In the case of xenon, special anomalies in isotopic composition due to extinct radioactive 1^7 atuj pu2^*
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From page 21... ...
Except for compositional determinations, those atmospheric measurements made by an early Martian lander will be designed to support biological or surface studies rather than for atmospheric studies. Drop-probes are of secondary value to study the Martian free atmosphere; their main objective would be to make a detailed chemical analysis of the lower atmosphere.
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From page 22... ...
Direct measurements of pressure and temperature by a probe into Jupiter's atmosphere would provide a direct test of atmospheric models and would require relatively simple instrumentation. Measurements with a mass spectrometer would provide an independent check on the atmospheric abundances, especially important in the case of the rare gases.
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From page 23... ...
Ground-Based and Near-Earth Studies of Planetary Atmospheres Observations from the surface of the Earth and from near-Earth orbit produce valuable information on the nearer planets, and for many years to come they will be our primary source of information on the more remote planets. Such observations are less expensive than planetary missions.
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From page 24... ...
High resolution imagery will be parctical in the wavelength interval from 2000 to 8000 A Imagery below 2000 A is possible, but the relatively long exposure times required makes compensation for blurring due to planetary rotation and motion increasingly difficult.
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From page 25... ...
Instruments should include plasma probes and magnetometers for solar plasma measurements; aeronomy instrumentation in certain cases for use during orbit decay into planetary atmospheres; radio occultation; imaging in the visible and infrared for meteorological studies, if the payload permits; microwave radiometry for Venus orbiters. Direct Impact Probes on Venus From the standpoint of planetary atmospheres, the study of the lower atmosphere of Venus is the most important single area in which rapid advance is possible at the present time.
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From page 26... ...
High resolution infrared spectroscopy may be used to map concentrations of polyatomic gases (including water vapor)
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