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A twenty-year wave in the diurnal anisotropy component of galactic cosmic rays arriving at the earth from the asymptotic direction 128 deg E of the sun has been found by Forbush. This wave is interpreted in terms of enhanced magnetic reconnection between the nearby galactic field and the field lines in the polar regions of the heliosphere during one half of the twenty-year solar magnetic cycle. This interpretation leads to the result that the component parallel to the solar rotation axis of the nearby galactic field is directed northward. (Author), Sponsored in part by Grant NSF-GA-1319.

The coronal structure to be expected during the solar eclipse of 22 September 1968 has recently been published. Prof. M. Waldmeier has made available a sketch that he prepared from photographs obtained during this eclipse. Many of the features seen in the eclipse (streamers, open-rayed configurations, and condensations) were in good qualitative agreement with those predicted from the model. Comparisons of the exact shape of many features may lead to improvements in the model and to a better understanding of coronal processes., Sponsored in part by the National Aeronautical Space Administration, Washington, D. C.

The configuration of coronal magnetic fields and the formation of new interplanetary magnetic sectors are discussed. Recurring energetic proton streams appear to be related to a persistent solar magnetic pattern. (Author), Supported in part by National Aeronautics and Space Administration, Washington, D. C., grants NsG-243 and NGR-05-003-230.

Interplanetary magnetic field observations with IMP-3 during eight solar rotations in the latter half of 1965 have been compared with the 3-hour Kp index. The results are consistent with those obtained with IMP-1 from three solar rotations in winter of 1963-4, indicating a stability in the response of geomagnetic activity during these years near solar activity minimum. The larger data sample in the present investigation reduces the probable error and delineates some interesting results. The average value of Kp decreases as the angle between the interplanetary field and the ecliptic changes from south to north. This is consistent with the reconnection of interplanetary and geomagnetic field lines as suggested by Dungey. As a function of interplanetary field magnitude B, the average value of the index ap is more linear than Kp, as might be expected. The relation can be described by ap = (1.5 plus or minus 0.1) B + 0.7 plus or minus 0.5. In the time interval covered by these observations the average value of Kp is consistently higher in sectors with interplanetary field directed away from the sun than in sectors with field directed toward the sun. (Author)

The longitude distribution of the solar flares that produced high-energy protons detected at the earth during the past 11-year sunspot cycle is examined. The synodic rotation period is not confined to be the Carrington period (27.2753 days) which corresponds to the use of heliographic longitude, but instead a range of rotation periods from 25 to 34 days is examined in increments of 0.01 days. It is concluded that the apparent tendency of these proton flares to cluster within one hemisphere of heliographic longitude is not statistically significant. (Author)