A New Interpretation of Martian Phenomena

Abstract

Mars is the only planet whose surface features can be observed in detail. Because its diurnal and seasonal changes are similar to those of the earth, it has been reasonable to attempt an explanation of its features in terms of terrestrial ones. Thus, the conspicuous and brilliant polar caps have been interpreted as snow and ice formations ; the blue and green of the dark areas as the springtime renewal of vegetation ; the brown of autumn as due to dying vegetation ; and the yellow veils, which at times completely mask the planet's surface, as sand and dust storms in a turbulent atmosphere. Yet a serious objection to these interpretations, recognized by many students of Mars, is the fact that there is no spectroscopic evidence for either oxygen or water vapor in the atmosphere, and both are essential for such explanations to be acceptable. Furthermore, the atmosphere is only slightly denser than the earth's atmosphere above Mt. Everest and, therefore, has only a limited capacity for holding dust in suspension. Recent spectrographic observations of Jupiter1 and Venus2 show strong absorption in the shortward regions of their spectra, beginning in the blue and extending into the ultraviolet beyond the limit reached by the spectrograms. Because the surface features of these planets are hidden from view by their optically dense atmospheres and cannot account for this optical extinction, the observed effects have been assumed to be due to a hitherto unsuspected molecular species. A wide search of possibilities led to nitrogen tetroxide. This is a compound that could occur in planetary matter, under proper conditions, as evidenced by the