In addltion to the magnetic globules iused silicate-magnetite globules were found in the area near the Tunguska epicentre this type of cosmic remnant has not been found elsewhere in the world. Most soil samples collected at random over the globe contain similar cosmic dust. The soil samples in the Tungus area contained numerous small more » magnetic globules with high Ni content, but although this affirms that the globules were of extraterrestrial origin, it does not necessarily mean that they originated from the Tungus Event. On the night of the Tungnska fall, and for several subsequent nights, the Tungus and adjacent regions experienced abnormally bright skies, and the whole of the northern hemisphere experienced anomalous extinction of atmospheric light subsequent to the fall. It is pointed out, however, that such a small hypothetical object cannot account for all the phenomena known to accompany the event. Reference is made to the Tungus Event of 1908 and to the suggestion of Jackson and Ryan (Nature 245: 88 (1973)) that a mini'' black hole was responsible for it. It is concluded that this rapid increase in the rate of growth was a direct result of the Tungus meteor crash. Moreover, the width of the annular growth rings of the trees increased by a factor of five after l908 as compared with previous years. A 250 year old pine tree from the region of the Tungus meteor crash of 1908 showed a sharp increase in radioactivity in 1908 as well as in l949. Thus, a 60 year old pine tree from the Urals showed a sharp increase in activity im l949 due to fall out from nuclear testimg. The activity of the inner rings is due to potassium, and that of the outer rings is due to fission products. However, a study of the radioactivity of growing trees from various regions of the Urals amd Siberia revealed the interesting fact that the annual growth rings im certain trees are a sensitive indicator of the increase in radioactivity and of the time of comtaminatlon of a locale with radioactive fall- out. It was found that fall-out due to recent nuclear testing contaminated dead wood more heavily than the wood in living trees, and the radioactivity of samples more » taken under the same conditions showed me relationship to the distance from the epicemter of the meteor crash. Pr/sup 144/ Most of the activity was shown to have a half-life of about ome year (the activity of control samples decreased by 30% in 5 momths). However, an analysis of the beta energies showed the presence of K/sup 40, Sr/sup 90/-Y/sup 90/ and Ce/sup 144. Samples taken at various distances from the epicenter of the 1908 Tungus meteor crash showed an apparent decrease in radioactivity with increasing distance from the point of impact.
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