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Erik Persson - One of the best experts on this subject based on the ideXlab platform.
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Attitudes towards the scientific search for Extraterrestrial Life among Swedish high school and university students
International Journal of Astrobiology, 2018Co-Authors: Erik Persson, Klara Anna CapovaAbstract:The aim of this study is to increase our understanding of the attitudes towards the scientific search for Extraterrestrial Life among high school and university students in Sweden. The most important results of the analysis are that: (a) the great majority of students believe that Extraterrestrial Life exists; (b) most students regard searching for Extraterrestrial Life to be quite important or very important; (c) very few students think that we should actively avoid searching for Extraterrestrial Life; (d) the most common motive for assigning a high priority to search for Extraterrestrial Life is that it is interesting, the most common motive for assigning a low priority is that such knowledge would not be practically useful, or that the money would be better spent elsewhere; (e) most students do not think they are very well informed regarding the search for Extraterrestrial Life. A higher percentage of the students who judge themselves to be well informed also believe that Extraterrestrial Life exists. We have also found some differences between subgroups (men/women, high school students/university students and different fields of study), but the differences are with few exceptions small in comparison with the overall trends, and they mostly differ in degree rather than direction.
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The History and Philosophy of Astrobiology: Perspectives on Extraterrestrial Life and the Human Mind
2013Co-Authors: David Duner, Erik Persson, Joel Parthemore, Gustav HolmbergAbstract:Human beings have wondered about the stars since the dawn of the species. Does Life exist out there – intelligent Life, even – or are we alone? The quest for Life in the universe touches on fundamental hopes and fears. It touches on the essence of what it means to formulate a theory, grasp a concept, and have an imagination. This book traces the history of the science of this area and the development of new schools in philosophy. Its essays seek to establish the history and philosophy of astrobiology as research fields in their own right by addressing cognitive, linguistic, epistemological, ethical, cultural, societal, and historical perspectives on astrobiology. The book is divided into three sections. The first (Cognition) focuses on the human mind and what it contributes to the search for Life. It explores the emergence and evolution of terrestrial Life and cognition and the challenges humans face as they reach to the stars. The essays raise philosophical questions, pose ethical dilemmas, and offer a variety of approaches, including one from cognitive zoology, in formulating a theory of the universal principles of intelligence, the limits of human conceptual abilities, and the human mind’s encounter with the unknown. The second section (Communication) examines the linguistic and semiotic requirements for interstellar communication. What is needed for successful communication? Are there universal rules for success? What are the possible features – and limitations – of exolanguages? What is required for recognizing a message as a message? The third section (Culture) considers cultural and societal issues. It explores astrobiology’s organization as a scientific discipline, its responsibilities to the public sphere, and its theological implications. It reviews the historically important panspermia hypothesis, along with the popularization of astrobiology and its ongoing institutionalisation. Through addressing these questions, we take our first steps in exploring the immense terra incognita of Extraterrestrial Life and the human mind.
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The Moral Status of Extraterrestrial Life.
Astrobiology, 2012Co-Authors: Erik PerssonAbstract:Abstract If we eventually discover Extraterrestrial Life, do we have any moral obligations for how to treat the Life-forms we find; does it matter whether they are intelligent, sentient, or just microbial—and does it matter that they are Extraterrestrial? In this paper, I examine these questions by looking at two of the basic questions in moral philosophy: What does it take to be a moral object? and What has value of what kind? I will start with the first of these questions by looking at the most important attempts to answer this question on our own planet and by asking whether and how they could be applied to Extraterrestrial Life. The results range from a very strong protection of all Extraterrestrial Life and all Extraterrestrial environments, whether inhabited or not, to total exclusion of Extraterrestrial Life. Subsequently, I also examine whether Extraterrestrial Life that lacks moral status can have value to human or alien Life with moral status, and if that could generate any obligations for how t...
Steven J. Dick - One of the best experts on this subject based on the ideXlab platform.
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Lessons Learned from the Twentieth-Century Extraterrestrial Life Debate
Space Time and Aliens, 2020Co-Authors: Steven J. DickAbstract:Now that historians have completed surveys of the Extraterrestrial Life debate such as Dick's Plurality of Worlds and The Biological Universe, and Crowe's, The Extraterrestrial Life debate, 1750–1900, we can begin to study the possible lessons learned from that history. In this chapter we make that attempt in three overlapping areas: (1) the problematic nature of evidence and inference, and its relation to scientific preconceptions; (2) the role of theory in raising expectations, interpreting observations, and generating conclusions; and (3) an evaluation of the success or failure of some of the debate’s most general arguments, including the principles of plenitude and mediocrity and “Goldilocks-type” arguments that Life occurs under such tight constraints that it is rare in the universe.
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The Twentieth Century History of the Extraterrestrial Life Debate: Major Themes
Space Time and Aliens, 2020Co-Authors: Steven J. DickAbstract:In this chapter we provide an overview of the Extraterrestrial Life debate since 1900, drawing largely on the major histories of the subject during this period, The Biological Universe, Life on Other Worlds, and The Living Universe, as well as other published works. We outline the major components of the debate, including (1) the role of planetary science, (2) the search for planets beyond the Solar System, (3) research on the origins of Life, and (4) the Search for Extraterrestrial Intelligence (SETI). We describe the birth of exobiology/astrobiology as a new discipline, emphasize the discovery of cosmic evolution as the proper context for the debate, and suggest that it is best seen as a worldview comparable to the great worldviews of the past.
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The Societal Impact of Extraterrestrial Life: The Relevance of History and the Social Sciences
Astrobiology History and Society, 2013Co-Authors: Steven J. DickAbstract:This chapter reviews past studies on the societal impact of Extraterrestrial Life and offers four related ways in which history is relevant to the subject: the history of impact thus far, analogical reasoning, impact studies in other areas of science and technology, and studies on the nature of discovery and exploration. We focus particularly on the promise and peril of analogical arguments, since they are by necessity widespread in the field. This chapter also summarizes the relevance of the social sciences, particularly anthropology and sociology, and concludes by taking a closer look at the possible impact of the discovery of Extraterrestrial Life on theology and philosophy. In undertaking this study we emphasize three bedrock principles: (1) we cannot predict the future; (2) society is not monolithic, implying many impacts depending on religion, culture and worldview; (3) the impact of any discovery of Extraterrestrial Life is scenario-dependent.
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The Twentieth Century History of the Extraterrestrial Life Debate: Major Themes and Lessons Learned
Astrobiology History and Society, 2013Co-Authors: Steven J. DickAbstract:In this chapter we provide an overview of the Extraterrestrial Life debate since 1900, drawing largely on the major histories of the subject during this period, The Biological Universe (Dick 1996), Life on Other Worlds (Dick 1998), and The Living Universe (Dick and Strick 2004), as well as other published work. We outline the major components of the debate, including (1) the role of planetary science, (2) the search for planets beyond the solar system, (3) research on the origins of Life, and (4) the Search for Extraterrestrial Intelligence (SETI). We emphasize the discovery of cosmic evolution as the proper context for the debate, reserving the cultural implications of astrobiology for part III of this volume. We conclude with possible lessons learned from this history, especially in the domains of the problematic nature of evidence, inference, and metaphysical preconceptions; the checkered role of theory; and an analysis of how representative general current arguments have fared in the past.
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Other Worlds: The Cultural Significance of the Extraterrestrial Life Debate
Leonardo, 1996Co-Authors: Steven J. DickAbstract:IIne of the most pervasive cultural influences of astronomy has been the idea that Life forms, perhaps far superior to our own, may exist beyond the Earth. This idea may be tied to the gods and goddesses of ancient myth and to the spiritual/celestial beings of religion or it may be, as some have suggested, a manifestation of an emotional need for imaginary beings [1]. What is certain is that we live in a time when the search for Extraterrestrial Life surrounds us. The Vi-
Andreas S. Bommarius - One of the best experts on this subject based on the ideXlab platform.
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search for Extraterrestrial Life using chiral molecules mandelate racemase as a test case
Astrobiology, 2006Co-Authors: Tracey L. Thaler, Phillip R. Gibbs, Rick Trebino, Andreas S. BommariusAbstract:We have investigated an enzymatic racemization reaction as a marker for Extraterrestrial Life, which resulted in a change in optical rotation of a mandelic acid over time, as measured by polarimetry. Mandelate racemase was active in aqueous buffer in a temperature range between 0 degrees C and 70 degrees C and also in concentrated ammonium salt solutions and water-in-oil microemulsions in a temperature range between -30 degrees C and 60-70 degrees C; however, the enzyme was not active in several organic cryosolvents. Thus, we have demonstrated that concentrated ammonium salt solutions and water-in-oil microemulsions, both of which are able to form on Extraterrestrial planets and moons in the presence of liquid water, are suitable media for enzyme reactions at subzero temperatures. Kinetic data for the mandelate racemase reaction obtained by polarimetry, while reproducible and internally consistent, differed significantly from several sets of data obtained previously by other methods such as chromatography and hydrogen-deuterium exchange. However, we conclude that reactions yielding a polarimetric signal, such as the racemizations employed in this work, are suitable mechanisms by which to utilize a change in chirality over time as a tool to detect signs of Life.
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Search for Extraterrestrial Life using chiral molecules: mandelate racemase as a test case.
Astrobiology, 2006Co-Authors: Tracey L. Thaler, Phillip R. Gibbs, Rick Trebino, Andreas S. BommariusAbstract:We have investigated an enzymatic racemization reaction as a marker for Extraterrestrial Life, which resulted in a change in optical rotation of a mandelic acid over time, as measured by polarimetry. Mandelate racemase was active in aqueous buffer in a temperature range between 0°C and 70°C and also in concentrated ammonium salt solutions and water-in-oil microemulsions in a temperature range between −30°C and 60–70°C; however, the enzyme was not active in several organic cryosolvents. Thus, we have demonstrated that concentrated ammonium salt solutions and water-in-oil microemulsions, both of which are able to form on Extraterrestrial planets and moons in the presence of liquid water, are suitable media for enzyme reactions at subzero temperatures. Kinetic data for the mandelate racemase reaction obtained by polarimetry, while reproducible and internally consistent, differed significantly from several sets of data obtained previously by other methods such as chromatography and hydrogen-deuterium exchange...
Lynn J. Rothschild - One of the best experts on this subject based on the ideXlab platform.
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Surface biosignatures of exo-Earths: Remote detection of Extraterrestrial Life
Proceedings of the National Academy of Sciences of the United States of America, 2015Co-Authors: Siddharth Hegde, Ivan G. Paulino-lima, Ryan E. Kent, Lisa Kaltenegger, Lynn J. RothschildAbstract:Exoplanet discovery has made remarkable progress, with the first rocky planets having been detected in the central star’s liquid water habitable zone. The remote sensing techniques used to characterize such planets for potential habitability and Life rely solely on our understanding of Life on Earth. The vegetation red edge from terrestrial land plants is often used as a direct signature of Life, but it occupies only a small niche in the environmental parameter space that binds Life on present-day Earth and has been widespread for only about 460 My. To more fully exploit the diversity of the one example of Life known, we measured the spectral characteristics of 137 microorganisms containing a range of pigments, including ones isolated from Earth’s most extreme environments. Our database covers the visible and near-infrared to the short-wavelength infrared (0.35–2.5 µm) portions of the electromagnetic spectrum and is made freely available from biosignatures.astro.cornell.edu. Our results show how the reflectance properties are dominated by the absorption of light by pigments in the visible portion and by strong absorptions by the cellular water of hydration in the infrared (up to 2.5 µm) portion of the spectrum. Our spectral library provides a broader and more realistic guide based on Earth Life for the search for surface features of Extraterrestrial Life. The library, when used as inputs for modeling disk-integrated spectra of exoplanets, in preparation for the next generation of space- and ground-based instruments, will increase the chances of detecting Life.
Bruce M. Jakosky - One of the best experts on this subject based on the ideXlab platform.
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Quest for Extraterrestrial Life
Nature, 2008Co-Authors: Bruce M. JakoskyAbstract:In The Living Cosmos, Chris Impey outlines current thinking on how and where we should look for signs of Extraterrestrial Life. In its 50-year history the science of astrobiology — or exobiology — has made great strides, fuelled by a series of successful Solar System probes. But, as Bruce Jakosky's book review points out, the future of the field will depend on the development of new technologies. Though if a Mars sample return mission does find a slot in NASA's post-2010 plans, perhaps a new edition of The Living Cosmos will be on the cards.
