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A red rain phenomenon occurred in Kerala, India starting from 25th July 2001, in which the rainwater appeared coloured in
various localized places that are spread over a few hundred kilometers in Kerala. Maximum cases were reported during the first
10 days and isolated cases were found to occur for about 2 months. The striking red colouration of the rainwater was found
to be due to the suspension of microscopic red particles having the appearance of biological cells. These particles have no
similarity with usual desert dust. An estimated minimum quantity of 50,000 kg of red particles has fallen from the sky through
red rain. An analysis of this strange phenomenon further shows that the conventional atmospheric transport processes like
dust storms etc. cannot explain this phenomenon. The electron microscopic study of the red particles shows fine cell structure
indicating their biological cell like nature. EDAX analysis shows that the major elements present in these cell like particles
are carbon and oxygen. Strangely, a test for DNA using Ethidium Bromide dye fluorescence technique indicates absence of DNA
in these cells. In the context of a suspected link between a meteor airburst event and the red rain, the possibility for the
extraterrestrial origin of these particles from cometary fragments is discussed. 相似文献
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G. H. A. Cole 《Surveys in Geophysics》2006,27(3):365-382
If intelligent life were common in the Universe, should we not be aware of it on Earth through contact with advanced space ships and automatic probes? Would we not at least expect to intercept communication signals between space travellers? That this is not found has led to much speculation in the past. Recent discoveries of planets around other stars (called here exoplanets) and, separately, recent discoveries in the evolution of life on Earth, including Homo sapiens, allow this question to be considered again but now with more information than before. This is the subject of the present paper. The study involves aspects of physics and chemistry in combination with biological studies. It is concluded here that the places where technologically capable intelligent life might be expected to be found in our Galaxy are so few that any such “centres of civilisation” must be separated by large distances, probably in excess of 50 light years. If true, this would make the different centres essentially isolated and would suggest that each manifestation of advanced intelligent life is a purely local development. This would agree with our experience of aloneness. Nevertheless, the number of centres throughout the Universe would still be astronomically large, even if each galaxy had only one centre. An hypothesis is proposed which could account for the existence of such centres in this form. 相似文献
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