The possibility to preserving the viability of molds in open space and (their capacity to overcome) overcoming the dense atmospheric layers in external containers of the Meteorite type. Experimental assessment
Abstract
Mankind had always worried by the issue of Earth life origin, and in the modern time — the time of space flights, the question which worries the humanity is the possibility to transfer the alien organisms both to the Earth from outside and to other planets during interplanetary flights. The discovery of structures resembling mineralized bacterial cells in the microcavities of the Martian basalt meteorite from Antarctica, announced by US President Bill Clinton in August 7, 1996 speech at NASA, sparked a new wave of interest to the theory of interplanetary panspermia, proposed in general terms by Svante Arrhenius. Microorganisms are able to maintain viability for a long time in conditions close to space. The most difficult stage of the journey from Mars to Earth is the overcoming of the dense layers of the Earth's atmosphere. To test the reality of the panspermia hypothesis, an external satellite basalt container "Meteorite" was developed in 2010. Experiments, performed in 2014, on the basis of this container data from the Photon-M4 satellite, showed that spore-forming bacteria are able to survive in microcavities of basalt meteorites while overcoming dense layers of the Earth's atmosphere. At the moment, we work on preliminary (preparing) experiments, using Meteorite container data as the basis, in order to test the possibility of mycelial fungi survival in such environment (conditions). If eukaryotic organisms are capable for such survival, then it is obvious that overcoming the dense layers of the Earth's atmosphere is not a significant obstacle to the introduction of life. During expeditionary work carried out in regions with different climatic conditions, samples of substrates (soil, litter, leaf litter, scrapings from rocky surfaces) were collected in habitats with high daily and annual temperature fluctuations or subjected to regular pyrogenic influences. Before isolating microorganisms, the substrates were subjected to sharp heating at various temperatures. As a result, a collection of 28 strains of mycelial fungi that survived at 10 minutes of temperatures — 120 - 170 °C — was created. Fungi with extremely heat-resistant propagules were detected in samples from different regions. They were also found in the permafrost soils of Oymyakon, where annual temperature fluctuations can exceed 100 °C (-70 - +35 °C). Although most of items were found in the southern regions, especially in open, sun-warmed places. In addition to the properties of the microorganisms themselves, the protective properties of the substrate is also of great importance for their survival. In order to create a model thermoprotective substrate which would be adequate from the point of view of the tested theory, a simulator of Martian soil in the dust fraction was made. It will be used as a carrier of fungi propagula, candidates for the next stage of the Meteorite experiment, in the selection of the organisms most resistant to short-term exposure to extremely high temperatures. This work was supported by Moscow State University Grant for Leading Scientific Schools «Depository of the Living Systems» in frame of the MSU Development Program.
- Publication:
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43rd COSPAR Scientific Assembly. Held 28 January - 4 February
- Pub Date:
- January 2021
- Bibcode:
- 2021cosp...43E1946D