[phys4phys] Naučno-stručni skup AOB (23.09.2022)

Wed Sep 14 15:50:30 CEST 2022

Poštovane koleginice i kolege,

u biblioteci Astronomske opservatorije biće održan *** Naučno-stručni skup *** u PETAK, 23. septembra sa početkom u 13h.

Tema: Microfossils in Carbonaceous Meteorites: Implications to the Distribution of Biospheres 

Izlagač: Richard B. Hoover - NASA Emeritus, United States Space and Rocket Center, One Tranquility Base, Huntsville, AL, USA 

Apstrakt:
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Carbonaceous meteorites are messengers from space. The Orgueil (CI1-France,1864) and Murchison (CM2-Australia, 1969) contain high percentages of extraterrestrial water (3–20%) and carbon (2-5 %), mainly in the form of a kerogen-like insoluble organic matter (IOM). Independent Scanning Electron Microscopy studies of meteorites were by Hoover at NASA/MSFC [2] and Rozanov ta the Borissiak Paleontological Institute (RAS) [3] revealed recognizable filamentous cyanobacteria in freshly fractured surfaces of the Murchison CM2 meteorite. Subsequent SEM studies have found well-preserved remains of diatoms, cyanobacteria and a diversity of other prokaryotic and eukaryotic microorganisms in many carbonaceous meteorites [4-6]. 

Carbonaceous meteorites contain 10 of the 20 life critical protein amino acid (some greater L-enantiomer excess than produced by abiotic processes) and 3 of the 5 nucleobases essential for life. Carbon isotope studies show the nucleobases in Murchison were indigenous, extraterrestrial and indicative of a cometary parent body [7]. Simonia [8] found that spectral lines of proteins and pigments such as Luciferase, Chlorophyll and other complex biomolecules produced only by biology precisely match many unidentified lines in the spectra of comets. However, PCR amplification studies sensitive enough to detect a single bacterium have failed to detect RNA, DNA and unstable life critical amino acids in meteorites. This provides clear and convincing evidence that the meteorites are not contaminated by terrestrial microbiota [9]. 

This presentation will provide new SEM images and EDS for diatoms, cyanobacteria and exotic microbes in meteorites. ENAA data will be presented showing astonishingly high levels of radiogenic Heat Producing Elements (40K, 238U and 232Th) in the Polonnaruwa/Aralaganwila meteorites. These low-density/high porosity stones are similar to the dark, low-density weak boulders (~Gargoyle Saxum) found on asteroid (101955) Bennu by OSIRIS Rex [10].  These results will be discussed in the context of haddal life in deep crustal rocks and oceans beneath icy crusts of moons and planets.  A novel “Wet Panspermia” hypothesis will be proposed with implications to the distribution of Life and Intact Biospheres throughout the Cosmos [11].

References: 
[1] Nagy B. Carbonaceous meteorites. Elsevier Science Publishing, 1975. 747 p. 
[2] Hoover R. B. Meteorites, Microfossils and Exobiology// Proceedings of SPIE. V. 3111, 1997. P. 115-136.
[3] Zhmur, S. I., Rozanov, A. Yu., et al., Lithified Remnants of Microorganisms in Carbonaceous Chondrites. Geochemistry International. 1997. V. 35, P. 58-60.
[4] Hoover, R. B. Fossils of Cyanobacteria in CI1 Carbonaceous Meteorites. Journal of Cosmology. 2011. V. 13, P. 1-49.
[5] Hoover, R. B. et al. (2018) Diatoms in the Orgueil Meteorite. Paleontological Journal, 52, 1647-1650.
[6] Rozanov, A. Yu., Hoover, R. B. et al.  The Orgueil Meteorite (Atlas of Microfossils). 2020. P. 1-130. ISBN 978-5-903825-42-4
[7] Ehrenfreund P. et al., (2001) Extraterrestrial amino acids in Orgueil and Ivuna: Tracing the parent body of CI type carbonaceous chondrites. PNAS, 2001. V. 98. 2138-2141.
[8] Simonia, I. and Cruikshank, D. P. (2018) Organic Molecules in the Icy Bodies of Planetary Systems – Accepted Notions and New Ideas. De Gruyter, Open Astron. 27, P. 341-355.
[9] Aerts J. et al. (2016) A contamination assessment of the CI carbonaceous meteorite Orgueil using a DNA-directed approach. Meteoritics & Planet. Sci. 51, 920–931. 
[10] Hoover, R.B., Frontasyeva, M.A. and Pavlov, S. Epithermal Neutron Activation Analysis of Carbonaceous Chondrites and the Polonnaruwa/ Aralaganwila Stone. Aspects Min Miner Sci. 6(1). AMMS. 000626. 2020. DOI: 10.31031/AMMS.2020.06.000626
[11] Hoover, R.B., Frontasyeva, M.A., Pavlov, S. Rozanov, A. Yu., Wallis, D. H. and Wickramasinghe, N. C.  ENAA and SEM Investigations of Carbonaceous Meteorites: Implications to the Distribution of Life and Biospheres. (2021) Academia Journal of Scientific Research 9(5) 096-104.          
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Za one koji nisu u mogućnosti da dođu u biblioteku, link za praćenje izlaganja uživo preko Webex-a:
https://matf.webex.com/matf/j.php?MTID=m0df6f48533477119677a062b54f9e179 <https://matf.webex.com/matf/j.php?MTID=m0df6f48533477119677a062b54f9e179>

Izlaganje će biti snimljeno i postavljeno na zvanični Youtube kanal Astronomske opservatorije (https://www.youtube.com/c/AstronomskaOpservatorijaBeograd <https://www.youtube.com/c/AstronomskaOpservatorijaBeograd><https://www.youtube.com/c/AstronomskaOpservatorijaBeograd <https://www.youtube.com/c/AstronomskaOpservatorijaBeograd>).

Dobrodošli!

O izlagaču:
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Professor Richard B. Hoover began work at the NASA/George C. Marshall Space Flight Center (MSFC) in 1966. His initial research was on application of Scatter Fringe Interferometery for metrology of advanced telescopes and Fraunhoffer Diffraction phenomena. He invented the Ealing-Hoover Diffraction Plates and developed Laser Retroreflectors for tracking Saturn V Moon rockets and glancing incidence x-ray mirrors for X-ray Astronomy applications. He was Co-Investigator for the SKYLAB ATM Experiment S-056 X-Ray Telescope Experiment. This telescope produced 25,000 high resolution x-ray images of the Sun yielding new information on Solar Flares, Coronal Loops and X-ray bright points. Prof. Hoover holds 13 US and 2 International Patents and was NASA Inventor of the Year in 1992. He established the Astrobiology program at NASA/MSFC and led scientific expeditions to many of the most hostile environments on Earth. These expeditions resulted in discovery and valid publication of 6 new Genera and 15 new species of extremophile bacteria and archaea previously unknown to Science. 

His Astrobiology research using Scanning Electron Microscopy resulted in the detection of well-preserved remains of fossilized cyanobacteria, acritarchs and diatoms in diverse carbonaceous meteorites. Energy Dispersive X-Ray Spectroscopy revealed C/O and C/N ratios establishing that these remains were ancient and indigenous rather than modern post-arrival biological contaminants.  In 2002, for his Scientific Expeditions and discoveries of microbial extremophiles and microfossils in meteorites, Prof. Hoover was elected Fellow National of the Explorers Club in 2001. 

Prof. Richard B. Hoover has Authored/Edited over 50 Books and 400 scientific papers on X-ray Optics, Solar Physics, Diatoms, Bacteria, Microfossils and Meteorites. He is Honorary Life Member, Planetary Studies Foundation, and served on the SPIE Board of Directors of (1989-2002). He was the 2001 SPIE President; recipient of 2009 SPIE Gold Medal of the Society in 2009; Visiting Research Professor, University of Buckingham Centre for Astrobiology and NASA/Emeritus-Docent, United States Space & Rocket Center. His research has been featured in films produced by: The Science Channel, NASA's Unexplained Files, The History Channel, Ancient Aliens, NHK Japan Television, National Science Foundation: “Science Nation: Extremophiles”, BBC, Discovery Channel and National Geographic. Prof. Dr. Richard B. Hoover was awarded the Degree and Title: Doctor of Sciences, Honoris Causa, Russian Academy of Sciences in a Ceremony held in the Presidium of the Academy on October 21, 2021.
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Ana Vudragović
Research Associate
Astronomical Observatory
Volgina 7, 11060 Belgrade, Serbia

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