elementary contents (weight percentage) in extraterrestrial minerals and terrestrial basalts

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Nordic winter school on A strobiology 1 percentage) in extraterrestrial percentage) in extraterrestrial minerals and terrestrial minerals and terrestrial basalts basalts 0 10 20 30 40 50 SiO2 TiO2 Al2O3 FeO M gO CaO N a2O Lunarsoil Chondrites Terrstial basalts

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Elementary contents (weight percentage) in extraterrestrial minerals and terrestrial basalts. Perseus hardware (Exobiology experiment) onboard MIR space station. Mounted hardware (core module). Principal scheme of sample cavity in Perseus hardware. MgF 2 glass. Dry films (samples). - PowerPoint PPT Presentation

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  • Elementary contents (weight percentage) in extraterrestrial minerals and terrestrial basalts

    Nordic winter school on Astrobiology

  • Perseus hardware (Exobiology experiment) onboard MIR space stationMounted hardware (core module)

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  • Principal scheme of sample cavity in Perseus hardware MgF2 glassDry films (samples) Experimental tubeDry films (samples) MgF2 glass

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  • Outside container, placed on the outer surface of Kosmos-2044 spacecraft; (A) Baseplate with sample holders. (B) Temperature sensor. (C) Gamma radiation dosimeter (D) Dry samples (Uridine + inorganic phosphate. Flight duration - 14 days, temperature variations from -13 to +67.

    AABCDDD

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  • Meduza cassette device for outside samples exposure

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  • Table 1 Quantitative yield of nucleotides (in % from initial nucleoside) synthesized in course of experiments performed at Earth orbit

    *Experiments were performed for uridine (Urd) only **Experiments were performed for adenosine (Ado), deoxyadenosine (dAdo) and cytosine (Cyt)

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  • Nordic winter school on Astrobiology

  • Formation of 5UMP (in % of the initial uridine amount) in different radiation conditions

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  • Principal scheme of sample cavity in the experimental hardware

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  • Confocal microscope imaging of irradiated pelliclesFilaments of adenosine shaped as branches without any mineral inclusions (up) and with lunar soil particles (down)

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  • Formation of 5AMP and survival of initial AMP in laboratory experimentsB in absence of lunar soil, C in presence of lunar soilTime, hoursTime, hours

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  • Formation of 5AMP and survival of initial AMP in laboratory experiments

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  • Aminoacids: experimental objectives

    To simulate some Martian environmental factors in laboratory conditionsTo study the influence of Martian soil analogues (limonite and basalt) over destruction of peptides irradiated by UV 254To evaluate the effect of different type of atmospheres on prebiotic synthesis of organic molecules To reveal the action of different Martian soil components over prebiotic synthesis

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  • Surface atmospheric pressure: ~6.1 mb (about 1/150th that of Earth's) Surface gas density: ~0.020 kg/m3 Atmospheric scale height: 11.1 km Average temperature: ~210 K (-63 degrees Celsius) Wind speeds: 2-7 m/s (summer), 5-10 m/s (fall), 17-30 m/s (dust storm) Carbon Dioxide (CO2) - 95.32% (percentage by moles): Nitrogen (N2) - 2.7; Argon (Ar) - 1.6% ; Oxygen (O2) - 0.13%; Carbon Monoxide (CO) - 0.08% Minor (ppm): Water (H2O) 210; Nitrogen Oxide (NO) 100; Neon (Ne) - 2.5; Krypton (Kr) - 0.3; Xenon (Xe) - 0.08

    Current Martian atmospheric data

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  • Properties and percentages of Martian soil*The chemical composition was determined by the two Viking Landers and by the Pathfinder rover (average of about 5 sites at the Pathfinder landing site Science, volume 278, December 5, 1997)

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  • Stability of Phe irradiated by VUV254 in presence of Martian soil analoguesB in the absence of minerals; C In association with limonite D in association with basalt

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  • Formation of polypeptides after UV254 exposure of dry films Phe+GlyB in the absence of minerals; C In association with limonite D in association with basalt

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  • Formation of dipeptides(GG) after UV254 exposure of dry samplesB in the absence of minerals; C In association with limonite D in association with basalt

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  • Stability of Phe and Gly after 5 months of irradiation associated with different minerals (% of the initial amount)

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  • Photochemical survival of Phe in different type of atmospheres

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  • Interaction of montmorillonite ((Na,K,Ca)(l,Fe,g)[(Si,Al)4O10](OH)2*nH2O) catalytic cites and aminoacid molecules leading to the peptide bond formation

    Formation of catalytically active cites on the mineral surface. Activation of amino acid molecules occurs on the edges of clay particles, enriched by AlO- groups. Activation of functional groups of zwitterions. Proton removal from aminogroup to AlO- of montmorillonite leads to the formation of nucleophilic amino group, required for dipeptide formation. Overall scheme of peptide bond formation. Final dimerization reaction involves to neighbor activated aminoacid molecules.

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  • Basic conclusions

    The amplification of molecular structure could occur under the action of VUV radiation leading to the formation of natural substances. Lunar soil (CI), Murchison(CM2) and Allende (CV3) meteorites promote synthesis of polypeptides and nucleotides.Solid-phase synthesis of important organic substances could occur at the surfaces of comets, asteroids, meteorites and dust particles (small Solar system bodies).Minerals of extraterrestrial origin exhibited protective properties against cosmic radiation thus allowing protobiomolecules to survive during long-duration space journey.Biological important substances could have been transported safely to the Earth surface during the prebiotic period of its evolution and later contribute into further evolving of organic matter.Such an approach could help in solving the paradox of quick life origin at the early Earth.

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