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The 1966 Douglas Solar Eclipse Expedition obtained photographic records of the intensity and polarization of the solar corona on November 12, from a site at Chiguata, Peru. The present paper amplifies a preliminary account in a special publication (Proceedings: Eclipse Symposium, Sao Jose dos Campos, February 5–9, 1968, in press). Here we shall give a more complete description of the equipment, its calibration, methods of reduction, and the results obtained. We compare the observed intensities and polarizations with those predicted by van de Hulst and point out structure indicated by the polarization data. These observations reveal the existence of complicated structures with intensities and polarizations both higher and lower than required by the van de Hulst model. In general high intensities correlate with high polarizations and low intensities with low polarization. However, some instances occur where seemingly normal intensities are associated with lower polarizations and low intensities with high polarizations. We account for these discrepancies in terms of electron concentrations along the line of sight, which do not occur in the simplified model corona. Further, we suggest that the existence of structure, such as streamers, rays, and so on, in the outer corona indicates that the current models tend to underestimate the importance of the K corona in this region.

Several years ago it was suggested that the sun might be responsible for the sofier component of cosmic radiation. It was further noted that an extremely lowfrequency electromagnetic radiation which was supposed to be of solar origin might cause cosmic radiation. Some modiflcations of the original concept have now become necessary. Most workers have taken for granted that the solar cosmic rays originate simultaneously with flare phenomenon. Even in violent fiares the energies of individual atoms are small. The production of cosmic rays requires some physical process capable of imparting high energy to a tew atoms. A process of ihis sort can occur only in regions of relatively low density. The comparatively high coronal density seems to preclude the possibiliiy of a process of this sont. As the wave moves into the low-pressure upper corona the above process might occur. (A.C.)

The phenomenological use of the term “astronomical turbulence” is reviewed and earlier conclusions that the physical nature of the phenomenon is more likely anisotropic mass-motion, or jet-prominences, than the customary aerodynamic turbulence are restated. The primary problem under such conditions is the relative importance of mechanical energy-transport and momentum transport in perturbing the structure of the atmosphere. The problem of the difference between kinetic temperatures of the atoms and electrons is treated, and it is concluded that the difference is negligible in those parts of the stellar atmosphere which are in a statistically-steady state.

whereby complex nuclei are built up by the addition of neutrons to lighter nuclei. It has in the past been assumed that only a negligible fraction of the atoms in interstellar space were in excited states. This depended on the assumption that the excitation probability was proportional to the radiant energy-density while the return to the normal state was rapid and spontaneous. It should be pointed out, however, that the metastability of certain excited states may be so strong that the spontaneous transition coefficient may not govern the equilibrium. Such states will be reached by double processes, and return to the normal state will also take place largely by double processes involving radiation. Atoms can exist in such metastable states in fractions

Multicolor photoelectric photometry of Venus, Mars, Jupiter and Saturn, noting phase curves and monochromatic geometric albedos of Mars and Jupiter

We have developed a method for calculating the emission-line profiles from an expanding envelope. The method applies to an envelope where the emission intensity varies with latitude. Some typically illustrative cases are considered.

The invisibility of Fraunhofer lines in the inner corona at solar eclipses first indicated the very high temperatures present there. Scattering by fast electrons presumably washes out the lines. In this article we emphasize that the evidence is still unclear whether the strongest photospheric absorption lines appear as wide depressions in the K corona, and we re-examine data pertinent to the discussion.

Martian atmosphere examined through its redness, its albedo and its surface markings, noting also the composition of its two layers of particulate matter