Abstract
Neutral interstellar matter entering the solar system has been considered in respect to its influences on the upper atmosphere. Calculations show that in consequence of the focussing effect due to the sun's gravitational field the incoming neutral hydrogen and helium under special, but possible conditions will represent a semi-annually varying density along the earth's orbit. The particle fluxes amounting at least to some 107 cm−2 sec−1, which are connected with these density-profiles and reach the upper atmosphere, show annual periodicities and so will cause annual variations of the densities of the light, atmospheric gas constituents. Especially it is to be expected, that so produced density variations of atmospheric hydrogen are important. Temperature increases caused by the energy flux of interstellar particles should in general only amount to a few thousandths of the CIRA-temperatures.
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Mitteilungen der Astronomischen Institute Bonn, Nr. 103.
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Fahr, H.J. On the influence of neutral interstellar matter on the upper atmosphere. Astrophys Space Sci 2, 474–495 (1968). https://doi.org/10.1007/BF02175923
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DOI: https://doi.org/10.1007/BF02175923