universe is incredibly large and old. Is it possible that over several billion years in this huge area of \u200b\u200blife appeared on only one planet? Or in space no one except us? In the face of such a perspective, we feel just uncomfortable. The news of the discovery of extraterrestrial beings przyjęlibyśmy not only with curiosity, but of relief. Even if it were the simplest single-celled organisms.
Such coverage could have a Martian ocean 3.5 billion years ago (Photo: NASA)
Life in space occupied until recently only the authors of the books and science fiction enthusiasts in the radio trying to catch the sound of the Universe signals given by the Others. The discoveries made in the last decade, however, that fantasy and speculation give way to carefully planned research, and the old questions: How did life and how it evolved? Is there extraterrestrial organisms living somewhere else? What is the future of life on Earth and in space? - Return to a new dimension. Answers to astrobiology is not looking for today - a new discipline integrating almost all scientific specialties.
The moment of her birth could be set up in 1998, NASA's Astrobiology Institute. Shortly thereafter, similar centers were created in Spain, Britain, France and Australia. European offices in the newly merged network EANA (European Exo / Astrobiology Network Association), which also acts created a half years ago Polish Centre for Research in the Field of Astrobiology and related fields, based at the University of Szczecin. The speed with which astrobiology has gained international recognition, is astonishing. In plejadzie issues of interest, perhaps the most attention focused on the extent of the problems today, the conditions under which life can exist on Earth (and by analogy also to other planets and their moons).
It turns out that there are organisms on our planet that live in volcanic hot springs - at temperatures exceeding 113 ° C. Other microorganisms that live just below the surface of rocks in the extremely dry valleys of Antarctica, fully abolish temperatures down to -15 degrees C. In terms of resistance to irradiation are unrivaled rekordzistkami bacteria Deinococcus radiodurans, which can withstand a dose of 5 thousand. times the lethal to humans. No less impressive record established by bacterial spores of Bacillus subtilis - do not lose viability after six years of exposure to cosmic rays and ultraviolet radiation on the outside of one of NASA satellites okołoziemskich!
extraordinary vitality recently discovered microbial puts new light on the problem of the origin of life and interplanetary exchange organisms. The concept of warm and tranquil pond Darwin as an incubator, which would have created life on our planet has only a few supporters. More and more researchers believe that the first living organisms emerged in volcanic hot springs underwater. In this world of eternal darkness, huge pressures and high temperatures, the whole complex ecosystems function, whose existence was not so long ago we did not have the slightest idea.
to making bold hypotheses have led us organic compounds discovered in meteorites belonging to the class of carbonaceous chondrites, where in addition to 70 kinds of amino acids found sugars, aldehydes, alcohols, and all sorts of aromatic hydrocarbons. Most of the surveyed meteorite was no more than 500 million years after the birth of the Sun (ie
4-4.5 billion years ago). Since the complex reactions of organic synthesis has already occurred at the earliest stages of evolution of the solar system, it might just then came the first fruits of life? Maybe they are still traces in the matter of the protoplanetary disk, which has survived almost intact in the nuclei of comets? The answer to these questions, we know in 2014, when the comet Churyumov-Gerasimienko European probe Rosetta will land. Natural
space vehicles by which simple organisms could reach the Earth from space, are meteorites. Critics of the concept of cosmic origins of life, until recently believed that none of the organisms in a meteorite przeżyłyby long stay in interplanetary space (not to mention landing on Earth, which in the case of meteorites rarely soft). Recent experiments have shown, however, is another. Common bacterial spores Baccilus subtilis were confined in different materials (the meteorite), and sent them into a simulated space travel. It turned out that if they were not exposed to ultraviolet light destroys the DNA, much of it was in! Some survived the thermal and kinetic effects of impact with the Earth, provided that a meteorite carrying them was not too small, and during the flight through the atmosphere firing underwent only the surface layer. Showed similar resistance to other microbes bezjądrowe - Archea and photosynthetic bacteria called blue-green algae.
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