Avi Blizovsky
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A scientist from Germany conducted an experiment that was published in Astrobiology magazine. The experiment shows that bacteria can survive in space conditions even for years.
The idea has been in the air in all space science discussions since 1864, when William Thompson Calvin told the Royal Society in Edinburgh: "The hypothesis according to which life was created on Earth through insemination that came from another world may seem wild and visionary, but I would just like to state that it is not an unscientific question." He repeated this in 1871, at the 41st meeting of the British Association for the Advancement of Science (which still exists today) using a colorful term: seed-bearing meteorites.
In 1903, the German journal Umschau published an article by Svante Arrhenius that took meteors out of the picture. Instead he argued that there are spores that wander through space, settle and colonize any suitable planet. Arrhenius called his theory Pan-spermia. (panspermia).
The spores, said Gerda Horneck of the DLR Space Center in Cologne, can withstand a variety of harsh conditions: heat, radiation, emptiness, malfunctions in hostile chemical substances such as alcohol, acetone and others. They also have a long shelf life. This is because the sensitive material, the DNA, is specially packaged and protected inside the spore.
However, these spores cannot survive direct exposure to ultraviolet radiation, Hornek wrote in his article Life and the Evolution of the Biosphere, in 2001. However, while Arnneus's pan-spermia theory is no longer valid, Kelvin's definition, components from which life was created, is coming back into vogue.
Hornock bases her theory on meteor-like material from experiments conducted on the Russian satellite Photon in 1994, 1997 and 1999. Photon carried within it an application known as Biopan. When the satellite was in space, a drawer was occasionally opened and the experiment was exposed to the cold and vacuum of space, and when the bioplane was in sunlight, the ultraviolet radiation and other rays had no interference from the atmosphere. Photon rotated, so that the bioprint experiment stayed in the cold and the heat of the sun several times in an orbit that lasted an hour and a half.
Hornock also examined the results of a similar American experiment. the Long Duration Exposure Facility, which traveled in space between 1984 and 1990. Hornek found that even after six years in space, over two-thirds of the bacterial spores survived and were returned to Earth. However, these spores were protected by a thin aluminum cover as well as chemical protection.
Hornek and her colleagues planted spores of the bacterium Bacillus subtilis in a variety of materials: clay, red sandstone, meteorite chips, simulation of Martian soil, and more. Some spores rested in the dust layer, others were mixed and stored in artificial meteorites a centimeter deep, while others were directly exposed to space or shadowed by a layer of dust. The others were exposed to biofan for two weeks.
Among the selection of rock and soil samples that meteorite experts and geologists recommended we work with, Hornek said, some of the materials (clay) have already been used in previous experiments and others are being used for the first time.
Only a millionth of the spores that were exposed to space or lightly shaded survived. Direct ultraviolet radiation attached to the DNA, causing changes in the chemical bonds as well as changing the bases, Hornek said. However, spores that were not exposed to ultraviolet light, i.e. stored in the dark, showed survival rates of between 50 percent and 97 percent. Hornek said.
For news on the Yahoo website, quoted from Astrobiology Magazine
living in space
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