Formation of Amino Acids and Nucleotide Bases in a Titan Atmosphere Simulation Experiment
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Bayesian Analysis of the Astrobiological Implications of Life's
Bayesian analysis of the astrobiological implications of life's early emergence on Earth David S. Spiegel ∗ y, Edwin L. Turner y z ∗Institute for Advanced Study, Princeton, NJ 08540,yDept. of Astrophysical Sciences, Princeton Univ., Princeton, NJ 08544, USA, and zInstitute for the Physics and Mathematics of the Universe, The Univ. of Tokyo, Kashiwa 227-8568, Japan Submitted to Proceedings of the National Academy of Sciences of the United States of America Life arose on Earth sometime in the first few hundred million years Any inferences about the probability of life arising (given after the young planet had cooled to the point that it could support the conditions present on the early Earth) must be informed water-based organisms on its surface. The early emergence of life by how long it took for the first living creatures to evolve. By on Earth has been taken as evidence that the probability of abiogen- definition, improbable events generally happen infrequently. esis is high, if starting from young-Earth-like conditions. We revisit It follows that the duration between events provides a metric this argument quantitatively in a Bayesian statistical framework. By (however imperfect) of the probability or rate of the events. constructing a simple model of the probability of abiogenesis, we calculate a Bayesian estimate of its posterior probability, given the The time-span between when Earth achieved pre-biotic condi- data that life emerged fairly early in Earth's history and that, billions tions suitable for abiogenesis plus generally habitable climatic of years later, curious creatures noted this fact and considered its conditions [5, 6, 7] and when life first arose, therefore, seems implications. -
Electrons, Life and the Evolution of Earth's Chemical Cycles
Electrons, Life and the Evolution of Earth’s Chemical Cycles OCN 623 – Chemical Oceanography 23 April 2013 Adaption of Brian Glazer lecture (based on Falkowski and Godfrey (2008) Phil. Trans. R. Soc. B, 363: 2705-2716) © 2013 F.J. Sansone Outline Earth’s geological, geochemical and biological co- evolution since formation - Early Earth - Origins of life - The great oxidation event - Linkage between global O and N cycles - Alternate explanations for the great oxidation event - The rise of oxygen and the evolution of life - The Phanerozoic How Does the Earth Work as a Biosphere? All organisms derive energy for growth and maintenance by moving electrons from a substrate to a product All substrates and products must ultimately be recycled All metabolic processes on Earth are prokaryotic and were developed in the Archean and/or Proterozoic Eons Earth’s Geological, Geochemical and Biological Co-evolution Since Formation Earth, ~3.5 Ga Ago • Earth cools to <100˚C • Shallow sea environment – Land covered by low egg- shaped hills and pillow lavas – Silt layers – Scattered volcanic islands and evaporite lagoons • Tides higher – Moon closer to Earth, days shorter • Atmosphere –CO2-rich, no O2 – UV-drenched landscape Faint Sun Paradox High atmospheric CO2 and CH4 important in early Earth -- balanced weak Sun to maintain temp Recycling of Atmospheric CO2 Liquid water on early Earth allowed a hydrologic cycle, carbonate and silicate mineral weathering to develop: 2+ - CaCO3 + CO2 + H2O = Ca + 2HCO3 2+ - CaSiO3 +2CO2 +3H2O = Ca + 2HCO3 + H4SIO4 Uptake -
Is Extraterrestrial Organic Matter Relevant to the Origin of Life on Earth?
IS EXTRATERRESTRIAL ORGANIC MATTER RELEVANT TO THE ORIGIN OF LIFE ON EARTH? D. C. B. WHITTET Department of Physics, Applied Physics and Astronomy, Rensselaer Polytechnic Institute, Troy, NY 12180, U.S.A. (Received 19 August 1996) Abstract. I review the relative importance of internal and external sources of prebiotic molecules on Earth at the time of life's origin 3.7 Gyr ago. The ef®ciency of synthesis in the Earth's atmosphere was critically dependent on its oxidation state. If the early atmosphere was non-reducing and CO2- dominated, external delivery might have been the dominant source. Interplanetary dust grains and micrometeorites currently deliver carbonaceous matter to the Earth's surface at a rate of 3 5 7 10 kg/yr (equivalent to a biomass in 2 Gyr), but this may have been as high as 5 10 kg/yr (a biomass in only 10 Myr) during the epoch of late bombardment. Much of the incoming material is in the form of chemically inactive kerogens and amorphous carbon; but if the Earth once had a dense (10-bar) atmosphere, small comets rich in a variety of prebiotic molecules may have been suf®ciently air-braked to land non-destructively. Lingering uncertainties regarding the impact history of the Earth and the density and composition of its early atmosphere limit our ability to draw ®rm conclusions. 1. Introduction In at least one sense, a connection between the Universe at large and life in our small corner of it is inevitable. The hydrogen, carbon, nitrogen, oxygen, and other elements that make up our bodies and other living things were created billions of years ago in the interiors of stars and, in the case of hydrogen, in the the Big Bang itself (see Trimble, 1997, in this volume for an eloquent review). -
51. Astrobiology: the Final Frontier of Science Education
www.astrosociety.org/uitc No. 51 - Summer 2000 © 2000, Astronomical Society of the Pacific, 390 Ashton Avenue, San Francisco, CA 94112. Astrobiology: The Final Frontier of Science Education by Jodi Asbell-Clarke and Jeff Lockwood What (or Whom) Are We Looking For? Where Do We Look? Lessons from Our Past The Search Is On What Does the Public Have to Learn from All This? A High School Curriculum in Astrobiology Astrobiology seems to be all the buzz these days. It was the focus of the ASP science symposium this summer; the University of Washington is offering it as a new Ph.D. program, and TERC (Technical Education Research Center) is developing a high school integrated science course based on it. So what is astrobiology? The NASA Astrobiology Institute defines this new discipline as the study of the origin, evolution, distribution, and destiny of life in the Universe. What this means for scientists is finding the means to blend research fields such as microbiology, geoscience, and astrophysics to collectively answer the largest looming questions of humankind. What it means for educators is an engaging and exciting discipline that is ripe for an integrated approach to science education. Virtually every topic that one deals with in high school science is embedded in astrobiology. What (or Whom) Are We Looking For? Movies and television shows such as Contact and Star Trek have teased viewers with the idea of life on other planets and even in other galaxies. Illustration courtesy of and © 2000 by These fictional accounts almost always deal with intelligent beings that have Kathleen L. -
Is It the First Use of the Word Astrobiology ? Author
Title : Is it the first use of the word Astrobiology ? Author : Danielle Briot Adress : Observatoire de Paris 61 avenue de l’Observatoire 75014 Paris France tel : 33(0)1 40 51 22 39 and 33(0)1 45 07 78 57 [email protected] running title : First use of the word Astrobiology ? 1 Abstract The research of life in Universe is a ancient quest that has taken different forms over the centuries. It has given rise to a new science, which is normally referred as Astrobiology. It is interesting to research when this word was used for the first time and when this science developed to represent the search for life in Universe as is done today. There are records of the usage of the word "Astrobiology" as early as 1935, in an article published in a French popular science magazine. Moreover this article is quite remarkable because its portrayal of the concept of the subject is very similar to that considered today. The author of this paper was Ary J. Sternfeld (1905 - 1980), who was ortherwise known as a poorly respected great pioneer of astronautics. We provide a brief description of his life, which was heavily influenced by the tragic events of the 20th century history, from Poland and France to Russia. He was a prolific scientific writer who wrote a number of very successful scientific books and papers. Keywords : History – Pioneers 2 1. Introduction The question of the life in the Universe, in relation with the question of the multiplicity of worlds, is very ancient and probably dates back to Greek philosophers. -
Evolutionary Processes Transpiring in the Stages of Lithopanspermia Ian Von Hegner
Evolutionary processes transpiring in the stages of lithopanspermia Ian von Hegner To cite this version: Ian von Hegner. Evolutionary processes transpiring in the stages of lithopanspermia. 2020. hal- 02548882v2 HAL Id: hal-02548882 https://hal.archives-ouvertes.fr/hal-02548882v2 Preprint submitted on 5 Aug 2020 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. HAL archives-ouvertes.fr | CCSD, April 2020. Evolutionary processes transpiring in the stages of lithopanspermia Ian von Hegner Aarhus University Abstract Lithopanspermia is a theory proposing a natural exchange of organisms between solar system bodies as a result of asteroidal or cometary impactors. Research has examined not only the physics of the stages themselves but also the survival probabilities for life in each stage. However, although life is the primary factor of interest in lithopanspermia, this life is mainly treated as a passive cargo. Life, however, does not merely passively receive an onslaught of stress from surroundings; instead, it reacts. Thus, planetary ejection, interplanetary transport, and planetary entry are only the first three factors in the equation. The other factors are the quality, quantity, and evolutionary strategy of the transported organisms. -
Life in the Outer Solar System Jupiter
Life in the Outer Solar System Jupiter Big R = 11R⊕ Massive M = 300 M⊕ = 2.5 all the rest Thick Atmosphere Mostly H2, He But also more complex molecules Colors, storms Like Miller - Urey Life in Jupiter Atmosphere? Sagan-Salpeter, etc. Sinkers (Plankton) Floaters (Fish) Hunters (Fish) Galileo Results on Jupiter Reached Jupiter Dec. 1995 Sent probe into Jupiter’s atmosphere at 100,000 mile/hour Decelerated at 230 g Lasted for 57 min. Found: Strong winds Turbulence, little lightning Life less likely? Surprise: Little or no H2O May have entered in an unusual place (fewer clouds) Europa (Moon of Jupiter) Surface: Fractured Ice Subsurface Oceans? (Heated from Inside) Close-up of “ice floes” Galileo - Jupiter’s Moons http://www.jpl.nasa.gov/galileo/index.html Europa has a (THIN!) atmosphere UV H H H O=O T hin O O2 H2O ATM Pressure ~ 10–11 Earth More evidence for resurfacing along cracks by “ice geysers” fluid ice or liquid water Organic molecules on Callisto & Ganymede, maybe Europa? Saturn • Big (9.4 R⊕) • Massive (95 M⊕) • Year 29.5 years • Day 0.43 days • Composition similar to Jupiter Titan • Moon of Saturn • Diameter ~0.4 Earth • Atmospheric Pressure = 1.5 × Earth • 85% Nitrogen BUT • Cold (~90 K) • Reducing atmosphere • Haze • Lab for prebiotic chemistry The Cassini-Huygens Mission • Launched 10/13/97 • Arrived Saturn 7/2004 • Cassini studies – Saturn – Moons • Huygens – Dropped onto Titan – Study atmosphere – Surface CASSINI SPACECRAFT Huygens Probe • Released from Cassini • Slowed by heat shield • Parachute deploys • Soft landing • Sample -
REOXIDATION of SPONGE IRON IS an EXOTHERMIC PROCESS DUE to REMOVAL of HYDROGEN‖ Prof
International Journal Of advance research in Science and Engineering http://www.ijarse.com (IJARSE) 2012, Vol. No.1, Issue No. I, July ISSN-2319-8354 ―REOXIDATION OF SPONGE IRON IS AN EXOTHERMIC PROCESS DUE TO REMOVAL OF HYDROGEN‖ Prof. Pushpendra Kumar Sharma1, Neeraj Singh Rajput2, Prof. Sachin Jain3 1Head Mechanical Engineering Department, NIIST, Bhopal 2Post Graduate Student, NIIST, Bhopal 3Asst. Professor, NIIST, Bhopal [email protected] Abstract— In the present era scarcity of high grade coal, high valuable process of coke production is a headache. So to get release from this problem huge amount of electric arc furnace and sponge iron production is increased. Sometimes Sponge iron transportation is a problematic situation, because during transportation chances of spontaneous burning of sponge iron are found, that is the effect of re-oxidation of sponge iron. Re-oxidation of sponge iron phenomenon refers to oxidation of metallic sponge iron in moisture condition. Metallic iron forms a strongly bonded Fe (OH)2 compound which causes increase in mass of sponge iron. The re-oxidation phenomenon is an exothermic process. Sponge iron is spongy in structure having large in porous area. Thus it is very much reactive and seeks for high oxidation. So the sponge iron produced is highly susceptible to re-oxidation. So it is important to study the kinetic of sponge iron re-oxidation. Keywords—Sponge iron, Iron ore, Coal, Dolomite, Power unit for initial power consuming unit. INTRODUCTION The conventional route for making steel consists of sintering/pelletization plants, ovens, blast and basic oxygen furnaces. Such plants need huge capital expenses and raw materials as they are the stringent requirements. -
(5) Field: Session Topic: Speaker
(5) Field: Earth Science/Geoscience/Environment Session Topic: Stable Isotopes in Earth and Space Science Speaker: Shogo Tachibana, The University of Tokyo 1. Introduction The present Earth’s atmosphere is made up of 78% of nitrogen, 21% of oxygen (we breathe oxygen to live!), and 1% of other gases. However, the present oxygen-rich atmosphere is not the Earth’s original atmosphere. The atmosphere changed its chemical composition in the history of Earth. The present oxygen-rich atmosphere was built up by photosynthesis of cyanobacteria, and it has been known that the Earth’s atmosphere contained almost no oxygen in the Archean (>2.5 billion years ago (Ga)). There have been several geological indicators for the atmospheric oxygen level such as presence of detrital pyrite and uraninite in sedimentary rocks for the reducing atmosphere and presence banded iron formations and red beds for the oxidizing atmosphere. Geological records for transition from the reducing atmosphere to the oxidation atmosphere (Great Oxygenation Event) have been found in the Paleoproterozoic sedimentary rocks. 2. Mass-independent fractionation of sulfur isotopes and its relation to the atmospheric chemistry Sulfur has four stable isotopes (32S, 33S, 34S, and 36S). Their average relative abundances in the solar system are 95.02%, 0.75%, 4.22%, and 0.017% for 32S, 33S, 34S, and 36S, respectively, but they can be varied by various physical, chemical, and/or biological processes. The variations of relative abundances of 32S and 34S in minerals or rocks have been used to understand geological and biological processes on the Earth. Other two minor isotopes (33S and 36S) had not been measured intensively because their relative abundances were assumed to vary with following the mass-dependent fractionation law. -
Laboratory-Scale Investigation of the Removal of Hydrogen Sulfide From
Laboratory-scale investigation of the removal of hydrogen sulfide from biogas and air using industrial waste-based sorbents Olumide Wesley Awe, Doan Pham Minh, Nathalie Lyczko, Ange Nzihou, Yaqian Zhao To cite this version: Olumide Wesley Awe, Doan Pham Minh, Nathalie Lyczko, Ange Nzihou, Yaqian Zhao. Laboratory- scale investigation of the removal of hydrogen sulfide from biogas and air using industrial waste- based sorbents. Journal of Environmental Chemical Engineering, Elsevier, 2017, 5 (2), p.1809-1820. 10.1016/j.jece.2017.03.023. hal-01619255 HAL Id: hal-01619255 https://hal.archives-ouvertes.fr/hal-01619255 Submitted on 20 Oct 2018 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Laboratory-scale investigation of the removal of hydrogen sulfide from biogas and air using industrial waste-based sorbents a,b, b, b b Olumide Wesley Awe *, Doan Pham Minh **, Nathalie Lyczko , Ange Nzihou , a Yaqian Zhao a Dooge Centre for Water Resources Research, School of Civil Engineering, University College Dublin, Newstead, Belfield, Dublin 4, Ireland b Universite’ de Toulouse, Mines Albi, CNRS UMR 5302, Centre RAPSODEE, Campus Jarlard, Albi, F-81013 cedex 09, France A B S T R A C T Biogas is a valuable renewable energy that can be used as a fuel or as raw material for the production of hydrogen, synthesis gas and chemicals. -
High Temperature, Reducing Atmosphere, Continuous Furnaces to 1800°C (3272°F)
industrial and laboratory furnaces www.cmfurnaces.com HIGH TEMPERATURE, REDUCING ATMOSPHERE, CONTINUOUS FURNACES TO 1800°C (3272°F) The CM 300 Series furnaces are available in a variety the 300 Series muffle design furnaces. When automated of configurations from manually loaded lab-scale units the pusher plates (carrier trays) form a train and are to fully automated production systems. These furnaces pushed through the furnace by an external stoker employ a molybdenum wound aluminum oxide muffle, device. All automation is located outside the heat typically D-shaped, designed to operate from 800°C envelope for ease of maintenance and long life. (1472°F) to 1700°C (3100°F) on the standard models Hydrogen, dissociated ammonia, forming gas or any and as high as 1800°C (3272°F) for special applications. other reducing atmosphere compatible the refractory The base model includes inclined doors with protective metal heating elements can be employed. The standard atmosphere flushes, high heat section, and a cooling gas panel includes all necessary pressure regulators, section. Depending on application requirements other flow meters, solenoids and pressure switches for both features are added such as preheat sections, binder primary processing atmosphere and standby safety removal sections, multiple zone controls, low or high nitrogen. All furnaces come complete with the CM dewpoint features, and turn-key automated pusher combustion atmosphere safety system. Full details are systems. available on request. The furnaces are constructed of heavy gauge steel that Temperature control is by microprocessor based is welded and reinforced. All power components and setpoint controllers operating in conjunction with controls are located on the main frame assembly. -
Atmospheric Nitrogen Evolution on Earth and Venus
Atmospheric nitrogen evolution on Earth and Venus The Harvard community has made this article openly available. Please share how this access benefits you. Your story matters Citation Wordsworth, R.D. 2016. “Atmospheric Nitrogen Evolution on Earth and Venus.” Earth and Planetary Science Letters 447 (August): 103–111. doi:10.1016/j.epsl.2016.04.002. http://dx.doi.org/10.1016/ j.epsl.2016.04.002. Published Version doi:10.1016/j.epsl.2016.04.002 Citable link http://nrs.harvard.edu/urn-3:HUL.InstRepos:27846862 Terms of Use This article was downloaded from Harvard University’s DASH repository, and is made available under the terms and conditions applicable to Open Access Policy Articles, as set forth at http:// nrs.harvard.edu/urn-3:HUL.InstRepos:dash.current.terms-of- use#OAP Atmospheric nitrogen evolution on Earth and Venus R. D. Wordsworth Harvard Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, Department of Earth and Planetary Sciences, Harvard University, Cambridge, MA 02138 Abstract Nitrogen is the most common element in Earth’s atmosphere and also appears to be present in significant amounts in the mantle. However, its long-term cycling between these two reservoirs remains poorly understood. Here a range of biotic and abiotic mechanisms are evaluated that could have caused nitrogen exchange between Earth’s surface and interior over time. In the Archean, biological nitrogen fixation was likely strongly limited by nutrient and/or electron acceptor constraints. Abiotic fixation of dinitrogen becomes efficient in strongly reducing atmospheres, but only once temperatures exceed around 1000 K.