Astrobiology最新文献

{"title":"Life Is Uncertain: Inherent Variability Exhibited by Organisms, and at Higher Levels of Biological Organization.","authors":"Joseph W Bull","doi":"10.1089/ast.2023.0094","DOIUrl":"10.1089/ast.2023.0094","url":null,"abstract":"<p><p>Organisms act stochastically. A not uncommon view in the ecological literature is that this is mainly due to the observer having insufficient information or a stochastic environment-and not partly because organisms themselves respond with inherent unpredictability. In this study, I compile the evidence that contradicts that view. Organisms generate uncertainty internally, which results in irreducible stochastic responses. I consider why: for instance, stochastic responses are associated with greater adaptability to changing environments and resource availability. Over longer timescales, biologically generated uncertainty influences behavior, evolution, and macroecological processes. Indeed, it could be stated that organisms are systems <i>defined</i> by the internal generation, magnification, and record-keeping of uncertainty as inputs to responses. Important practical implications arise if organisms can indeed be defined by an association with specific classes of inherent uncertainty: not least that isolating those signatures then provides a potential means for detecting life, for considering the forms that life could theoretically take, and for exploring the wider limits to how life might become distributed. These are all fundamental goals in astrobiology.</p>","PeriodicalId":8645,"journal":{"name":"Astrobiology","volume":null,"pages":null},"PeriodicalIF":4.2,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139728871","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Planetary Protection Knowledge Gap Closure Enabling Crewed Missions to Mars.","authors":"James A Spry, Bette Siegel, Corien Bakermans, David W Beaty, Mary-Sue Bell, James N Benardini, Rosalba Bonaccorsi, Sarah L Castro-Wallace, David A Coil, Athena Coustenis, Peter T Doran, Lori Fenton, David P Fidler, Brian Glass, Stephen J Hoffman, Fathi Karouia, Joel S Levine, Mark L Lupisella, Javier Martin-Torres, Rakesh Mogul, Karen Olsson-Francis, Sandra Ortega-Ugalde, Manish R Patel, David A Pearce, Margaret S Race, Aaron B Regberg, Petra Rettberg, John D Rummel, Kevin Y Sato, Andrew C Schuerger, Elliot Sefton-Nash, Matthew Sharkey, Nitin K Singh, Silvio Sinibaldi, Perry Stabekis, Carol R Stoker, Kasthuri J Venkateswaran, Robert R Zimmerman, Maria-Paz Zorzano-Mier","doi":"10.1089/ast.2023.0092","DOIUrl":"10.1089/ast.2023.0092","url":null,"abstract":"<p><p>As focus for exploration of Mars transitions from current robotic explorers to development of crewed missions, it remains important to protect the integrity of scientific investigations at Mars, as well as protect the Earth's biosphere from any potential harmful effects from returned martian material. This is the discipline of planetary protection, and the Committee on Space Research (COSPAR) maintains the consensus international policy and guidelines on how this is implemented. Based on National Aeronautics and Space Administration (NASA) and European Space Agency (ESA) studies that began in 2001, COSPAR adopted principles and guidelines for human missions to Mars in 2008. At that point, it was clear that to move from those qualitative provisions, a great deal of work and interaction with spacecraft designers would be necessary to generate meaningful quantitative recommendations that could embody the intent of the Outer Space Treaty (Article IX) in the design of such missions. Beginning in 2016, COSPAR then sponsored a multiyear interdisciplinary meeting series to address planetary protection \"knowledge gaps\" (KGs) with the intent of adapting and extending the current robotic mission-focused Planetary Protection Policy to support the design and implementation of crewed and hybrid exploration missions. This article describes the outcome of the interdisciplinary COSPAR meeting series, to describe and address these KGs, as well as identify potential paths to gap closure. It includes the background scientific basis for each topic area and knowledge updates since the meeting series ended. In particular, credible solutions for KG closure are described for the three topic areas of (1) microbial monitoring of spacecraft and crew health; (2) natural transport (and survival) of terrestrial microbial contamination at Mars, and (3) the technology and operation of spacecraft systems for contamination control. The article includes a KG data table on these topic areas, which is intended to be a point of departure for making future progress in developing an end-to-end planetary protection requirements implementation solution for a crewed mission to Mars. Overall, the workshop series has provided evidence of the feasibility of planetary protection implementation for a crewed Mars mission, given (1) the establishment of needed zoning, emission, transport, and survival parameters for terrestrial biological contamination and (2) the creation of an accepted risk-based compliance approach for adoption by spacefaring actors including national space agencies and commercial/nongovernment organizations.</p>","PeriodicalId":8645,"journal":{"name":"Astrobiology","volume":null,"pages":null},"PeriodicalIF":4.2,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140179225","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Chapter 1: The Astrobiology Primer 3.0.","authors":"Micah J Schaible, Nadia Szeinbaum, G Ozan Bozdag, Luoth Chou, Natalie Grefenstette, Stephanie Colón-Santos, Laura E Rodriguez, M J Styczinski, Jennifer L Thweatt, Zoe R Todd, Alberto Vázquez-Salazar, Alyssa Adams, M N Araújo, Thiago Altair, Schuyler Borges, Dana Burton, José Alberto Campillo-Balderas, Eryn M Cangi, Tristan Caro, Enrico Catalano, Kimberly Chen, Peter L Conlin, Z S Cooper, Theresa M Fisher, Santiago Mestre Fos, Amanda Garcia, D M Glaser, Chester E Harman, Ninos Y Hermis, M Hooks, K Johnson-Finn, Owen Lehmer, Ricardo Hernández-Morales, Kynan H G Hughson, Rodrigo Jácome, Tony Z Jia, Jeffrey J Marlow, Jordan McKaig, Veronica Mierzejewski, Israel Muñoz-Velasco, Ceren Nural, Gina C Oliver, Petar I Penev, Chinmayee Govinda Raj, Tyler P Roche, Mary C Sabuda, George A Schaible, Serhat Sevgen, Pritvik Sinhadc, Luke H Steller, Kamil Stelmach, J Tarnas, Frank Tavares, Gareth Trubl, Monica Vidaurri, Lena Vincent, Jessica M Weber, Maggie Meiqi Weng, Regina L Wilpiszeki, Amber Young","doi":"10.1089/ast.2021.0129","DOIUrl":"10.1089/ast.2021.0129","url":null,"abstract":"<p><p>The Astrobiology Primer 3.0 (ABP3.0) is a concise introduction to the field of astrobiology for students and others who are new to the field of astrobiology. It provides an entry into the broader materials in this supplementary issue of <i>Astrobiology</i> and an overview of the investigations and driving hypotheses that make up this interdisciplinary field. The content of this chapter was adapted from the other 10 articles in this supplementary issue and thus represents the contribution of all the authors who worked on these introductory articles. The content of this chapter is not exhaustive and represents the topics that the authors found to be the most important and compelling in a dynamic and changing field.</p>","PeriodicalId":8645,"journal":{"name":"Astrobiology","volume":null,"pages":null},"PeriodicalIF":4.2,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140157497","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Chapter 11: Astrobiology Education, Engagement, and Resources.","authors":"M J Styczinski, D M Glaser, M Hooks, T Z Jia, K Johnson-Finn, G A Schaible, M J Schaible","doi":"10.1089/ast.2021.0098","DOIUrl":"10.1089/ast.2021.0098","url":null,"abstract":"<p><p>Although astrobiology is a relatively new field of science, the questions it seeks to answer (<i>e.g.,</i> \"What is life?\" \"What does life require?\") have been investigated for millennia. In recent decades, formal programs dedicated specifically to the science of astrobiology have been organized at academic, governmental, and institutional scales. Constructing educational programs around this emerging science relies on input from broad expertise and backgrounds. Because of the interdisciplinary nature of this field, career pathways in astrobiology often begin in more specific fields such as astronomy, geology, or biology, and unlike many other sciences, typically involve substantial training outside one's primary discipline. The recent origin of astrobiology as a field of science has led to strong collaborations with education research in the development of astrobiology courses and offers a unique instructional laboratory for further pedagogical studies. This chapter is intended to support students, educators, and early career scientists by connecting them to materials and opportunities that the authors and colleagues have found advantageous. Annotated lists of relevant programs and resources are included as a series of appendices in the supplementary material.</p>","PeriodicalId":8645,"journal":{"name":"Astrobiology","volume":null,"pages":null},"PeriodicalIF":4.2,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140157499","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Chapter 2: What Is Life?","authors":"Stephanie Colón-Santos, Alberto Vázquez-Salazar, Alyssa Adams, José Alberto Campillo-Balderas, Ricardo Hernández-Morales, Rodrigo Jácome, Israel Muñoz-Velasco, Laura E Rodriguez, Micah J Schaible, George A Schaible, Nadia Szeinbaum, Jennifer L Thweatt, Gareth Trubl","doi":"10.1089/ast.2021.0116","DOIUrl":"10.1089/ast.2021.0116","url":null,"abstract":"<p><p>The question \"What is life?\" has existed since the beginning of recorded history. However, the scientific and philosophical contexts of this question have changed and been refined as advancements in technology have revealed both fine details and broad connections in the network of life on Earth. Understanding the framework of the question \"What is life?\" is central to formulating other questions such as \"Where else could life be?\" and \"How do we search for life elsewhere?\" While many of these questions are addressed throughout the Astrobiology Primer 3.0, this chapter gives historical context for defining life, highlights conceptual characteristics shared by all life on Earth as well as key features used to describe it, discusses why it matters for astrobiology, and explores both challenges and opportunities for finding an informative operational definition.</p>","PeriodicalId":8645,"journal":{"name":"Astrobiology","volume":null,"pages":null},"PeriodicalIF":4.2,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140157500","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"In Memoriam: Wayne Lowell Nicholson, March 26, 1958-June 8, 2023.","authors":"Jamie S Foster, Tina M Henkin, Tony Romeo, Andrew C Schuerger, Peter Setlow, Robert J Ferl, Kelly C Rice, Eric W Triplett, Patricia Fajardo-Cavazos","doi":"10.1089/ast.2023.0100","DOIUrl":"10.1089/ast.2023.0100","url":null,"abstract":"","PeriodicalId":8645,"journal":{"name":"Astrobiology","volume":null,"pages":null},"PeriodicalIF":4.2,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139048283","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hardware Development for Plant Cultivation Allowing <i>In Situ</i> Fluorescence Analysis of Calcium Fluxes in Plant Roots Under Microgravity and Ground-Control Conditions.","authors":"Magnus Rath, Michaela Dümmer, Jens Hauslage, Christian Liemersdorf, Christoph Forreiter","doi":"10.1089/ast.2023.0038","DOIUrl":"10.1089/ast.2023.0038","url":null,"abstract":"<p><p>Maintaining an optimal leaf and stem orientation to yield a maximum photosynthetic output is accomplished by terrestrial plants using sophisticated mechanisms to balance their orientation relative to the Earth's gravity vector and the direction of sunlight. Knowledge of the signal transduction chains of both gravity and light perception and how they influence each other is essential for understanding plant development on Earth and plant cultivation in space environments. However, <i>in situ</i> analyses of cellular signal transduction processes in weightlessness, such as live cell imaging of signaling molecules using confocal fluorescence microscopy, require an adapted experimental setup that meets the special requirements of a microgravity environment. In addition, investigations under prolonged microgravity conditions require extensive resources, are rarely accessible, and do not allow for immediate sample preparation for the actual microscopic analysis. Therefore, supply concepts are needed that ensure both the viability of the contained plants over a longer period of time and an unhindered microscopic analysis in microgravity. Here, we present a customized supply unit specifically designed to study gravity-induced Ca²⁺ mobilization in roots of <i>Arabidopsis thaliana</i>. The unit can be employed for ground-based experiments, in parabolic flights, on sounding rockets, and probably also aboard the International Space Station.</p>","PeriodicalId":8645,"journal":{"name":"Astrobiology","volume":null,"pages":null},"PeriodicalIF":4.2,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140179224","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Chapter 10: Planetary Protection-History, Science, and the Future.","authors":"Jordan McKaig, Tristan Caro, Dana Burton, Frank Tavares, Monica Vidaurri","doi":"10.1089/ast.2021.0112","DOIUrl":"10.1089/ast.2021.0112","url":null,"abstract":"<p><p>Planetary protection is a principle in the design of interplanetary missions that aims to prevent biological cross contamination between the target body and Earth. Planetary protection policies and procedures have worked to mitigate forward contamination (from Earth) and back contamination (to Earth) since the beginning of the space age. Today, planetary protection policy is guided by international agreements, nongovernmental advisory councils, and national space agencies. The landscape of planetary protection science and policy is changing rapidly, as new technologies, crewed missions to Mars and the Moon, and even orbital settlements are being developed. Space exploration, whether specifically targeted toward questions in astrobiology or not, must consider planetary protection concerns to minimize contamination that poses a risk to both astrobiological investigations as well as Earth's biosphere. In this chapter, we provide an introduction to and overview of the history, motivations, and implementation of planetary protection in the United States.</p>","PeriodicalId":8645,"journal":{"name":"Astrobiology","volume":null,"pages":null},"PeriodicalIF":4.2,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140157498","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Chapter 6: The Breadth and Limits of Life on Earth.","authors":"Jennifer L Thweatt, C E Harman, M N Araújo, Jeffrey J Marlow, Gina C Oliver, Mary C Sabuda, Serhat Sevgen, Regina L Wilpiszeki","doi":"10.1089/ast.2021.0131","DOIUrl":"10.1089/ast.2021.0131","url":null,"abstract":"<p><p>Scientific ideas about the potential existence of life elsewhere in the universe are predominantly informed by knowledge about life on Earth. Over the past ∼4 billion years, life on Earth has evolved into millions of unique species. Life now inhabits nearly every environmental niche on Earth that has been explored. Despite the wide variety of species and diverse biochemistry of modern life, many features, such as energy production mechanisms and nutrient requirements, are conserved across the Tree of Life. Such conserved features help define the operational parameters required by life and therefore help direct the exploration and evaluation of habitability in extraterrestrial environments. As new diversity in the Tree of Life continues to expand, so do the known limits of life on Earth and the range of environments considered habitable elsewhere. The metabolic processes used by organisms living on the edge of habitability provide insights into the types of environments that would be most suitable to hosting extraterrestrial life, crucial for planning and developing future astrobiology missions. This chapter will introduce readers to the breadth and limits of life on Earth and show how the study of life at the extremes can inform the broader field of astrobiology.</p>","PeriodicalId":8645,"journal":{"name":"Astrobiology","volume":null,"pages":null},"PeriodicalIF":4.2,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140157504","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Chapter 7: Assessing Habitability Beyond Earth.","authors":"M J Styczinski, Z S Cooper, D M Glaser, O Lehmer, V Mierzejewski, J Tarnas","doi":"10.1089/ast.2021.0097","DOIUrl":"10.1089/ast.2021.0097","url":null,"abstract":"<p><p>All known life on Earth inhabits environments that maintain conditions between certain extremes of temperature, chemical composition, energy availability, and so on (Chapter 6). Life may have emerged in similar environments elsewhere in the Solar System and beyond. The ongoing search for life elsewhere mainly focuses on those environments most likely to support life, now or in the past-that is, potentially habitable environments. Discussion of habitability is necessarily based on what we know about life on Earth, as it is our only example. This chapter gives an overview of the known and presumed requirements for life on Earth and discusses how these requirements can be used to assess the potential habitability of planetary bodies across the Solar System and beyond. We first consider the chemical requirements of life and potential feedback effects that the presence of life can have on habitable conditions, and then the planetary, stellar, and temporal requirements for habitability. We then review the state of knowledge on the potential habitability of bodies across the Solar System and exoplanets, with a particular focus on Mars, Venus, Europa, and Enceladus. While reviewing the case for the potential habitability of each body, we summarize the most prominent and impactful studies that have informed the perspective on where habitable environments are likely to be found.</p>","PeriodicalId":8645,"journal":{"name":"Astrobiology","volume":null,"pages":null},"PeriodicalIF":4.2,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140157505","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}