Tuesday, January 3, 2012

The presence of traces of life in meteorites



In the study of carbon (carbonaceous) meteorites show in their composition of matter, which on Earth are the products of life.

In the study of the stony meteorites are sometimes found so-called "organized elements" - the microscopic (5-50 um) "unicellular" education, often with a pronounced double-walled, pores, pimples, etc.

To date, not an indisputable fact that these fossils belong to the remains of any of extraterrestrial life forms. But on the other hand, these formations have a high degree of organization, which is usually associated with life.

Feature of the "organized elements" is also their numbers: 1, the substances carbonaceous meteorites have approximately 1800 "organized elements". 

In August 1996 in the journal Science published an article on the study of the meteorite ALH 84 001 , found in Antarctica in 1984. Isotope dating showed that the meteorite originated 4-4.5 billion years ago, and 15 million years ago was thrown out into interplanetary space. 13 000 years ago a meteorite fell to Earth. By studying the meteorite using electron microscopy , the scientists found microscopic fossils that resemble bacterial colonies, consisting of parts of size about 100 nm. Were also found traces of substances formed by decomposition of microorganisms. The work was greeted with mixed scientific community. Critics noted that the size of structures found in the 100-1000 times smaller than typical terrestrial bacteria, and their volume is too small to accommodate molecules of DNA and RNA . In subsequent studies in the samples had traces of terrestrial biozagryazneny. In general, the arguments in favor of the formation are fossils of bacteria seem unconvincing.



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