Astrobiology最新文献

{"title":"The Viking's 50 Year Landing Anniversary Astrobiology Special Collection: Reexamining the Revolutionary Impact of Viking on Mars Exploration.","authors":"Mary Beth Wilhelm, Scott M Perl","doi":"10.1177/15311074261464719","DOIUrl":"10.1177/15311074261464719","url":null,"abstract":"<p><p>The NASA Viking Program laid the framework for Mars science, technology, and exploration. While the barren view of the Red Planet revealed by Viking was antithetical to the expectations of the planetary science community at the time, Viking was remarkable because it achieved numerous novel technical feats that continue to shape planetary robotic exploration today, integrating technical elements from disparate scientific fields, culminating in the scientific, engineering, and management achievements of over 2000 people. Over the last five decades, the results of the Viking science payload have led to vigorous debate within the astrobiology community on the burden of proof necessary to determine the detection of life, a necessary discussion that continues today. The future of missions designed to search for extant life will build upon the foundation laid by Viking, with a scientifically integrated, matured search-for-life strategy, one invigorated by technologists, engineers, and science communicators. As we celebrate the 50th anniversary of this groundbreaking mission, it is imperative that the scientific community reflects the Viking program's foundational impact on planetary science and exploration. Looking to the future, we must consider the perspectives and lessons learned from Viking while working towards a long-term vision for continued astrobiological exploration of Mars and other planetary bodies.</p>","PeriodicalId":8645,"journal":{"name":"Astrobiology","volume":" ","pages":"9S-11S"},"PeriodicalIF":2.3,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148359170","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":"Viking at 50: Rediscovering the People and Ideas That Formed Astrobiology.","authors":"Aaron McKinnon, Neveda Naz","doi":"10.1177/15311074261463022","DOIUrl":"10.1177/15311074261463022","url":null,"abstract":"<p><p>This article presents a historical preface to the <i>Astrobiology</i> special collection by introducing the actors, timeline, and intellectual framework involved in the National Aeronautics and Space Administration's (NASA) Viking mission. The authors pull information from scholarly articles, historical records, and the personal notes of Viking scientists uncovered this year and currently en route to the National Archives. Revisiting the legacy of Viking here provides a brief look into the science that continues to inform the practice of astrobiology and the creative spirit that inspires its scientists. All figures presented in this article have not previously been publicly available and will be made so later this year in the Exobiology Branch Collection at NASA's Ames Research Center Archives (collection ARC11.17). The authors encourage space history and astrobiology researchers to consult the soon-to-be accessioned Viking-era records housed in the Ames archives for new insights into America's first landing on Mars.</p>","PeriodicalId":8645,"journal":{"name":"Astrobiology","volume":" ","pages":"12S-17S"},"PeriodicalIF":2.3,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148275859","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":"Rethinking the Last Universal Common Ancestor of Life: Network Convergence and the Root of the Tree.","authors":"Jessica C Bowman, Nigel Goldenfeld, Karyn L Rogers, Anton S Petrov, Loren Dean Williams","doi":"10.1177/15311074261452809","DOIUrl":"10.1177/15311074261452809","url":null,"abstract":"<p><p>The tree of life is rooted at the \"origin of life.\" One model holds that core biochemistry, which includes the genetic code, the ribosome, biopolymer backbones, and amino acid and nucleotide monomer alphabets, was inherited vertically from a single origin of life. In this model, core biochemistry is a frozen accident that reflects prebiotic chemistry. In an alternative model explored here, life arose across diverse planetary environments and generated diverse biochemistries that competed and cooperated. These biochemistries converged through selection driven by the \"network effect.\" The network effect conferred greater fitness on participants in increasingly dominant biochemistries: the more extensive the adoption of a biochemistry, the greater the benefits for systems using it. In this model, the evolution of core biochemistry was driven, in part, by compatibility, integration, and coordination. The last universal common ancestor (LUCA) in this model represents a diffuse tipping process-where biochemical convergence reached critical mass. LUCA is a process of convergence rather than a specific organism or collection of organisms. At the tipping point, the biosphere committed to the transition from competing biochemical platforms to a universal standard. After the tipping point, biological innovation exploded, with fixed core biochemistry. This model makes testable predictions: core biochemistry should show evidence of evolutionary optimization rather than frozen accidents; core biochemistry should show molecular entanglement that reflects incremental coevolution; and biosynthetic pathways should differ from prebiotic chemistry. These predictions appear to be supported by observations.</p>","PeriodicalId":8645,"journal":{"name":"Astrobiology","volume":" ","pages":"625-632"},"PeriodicalIF":2.3,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148154903","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":"From Polymerization-Enabled Folding and Assembly to Chemical Evolution: Key Processes for Emergence of Functional Polymers in the Origin of Life.","authors":"Rotem Edri, Manesh Prakash Joshi, Moran Frenkel-Pinter, Nicholas V Hud, Christine D Keating, Luke J Leman","doi":"10.1177/15311074251365943","DOIUrl":"10.1177/15311074251365943","url":null,"abstract":"<p><p>Chemical and geological processes on prebiotic Earth are believed to have resulted in the emergence of life through the increasing organization and functionality of organic molecules. This primer provides an overview of some key abiotic chemical and physical processes that could have contributed to life's building blocks (amino acids, nucleotides, fatty acids, and monosaccharides) becoming more ordered during the early stages in the origin of life. The processes considered include polymerization, intramolecular folding, multimolecular assembly, and chemical evolution through various selective mechanisms. Our goal is to provide an accessible, high-level synopsis of these key general concepts for a diverse audience.</p>","PeriodicalId":8645,"journal":{"name":"Astrobiology","volume":" ","pages":"608-624"},"PeriodicalIF":2.3,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144940289","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":"Astrobiology in the Time of Artificial Intelligence.","authors":"Caleb Scharf","doi":"10.1177/15311074261463025","DOIUrl":"10.1177/15311074261463025","url":null,"abstract":"<p><p>The Viking missions showcased multiple spaceflight technologies that represented state-of-the-art capabilities: From digital line-scan imaging to the operation of complex onboard laboratories and software-controlled process autonomy. Since Viking, there have been extraordinary, and still accelerating, advancements in computing technology that impact science, society, and exploration. These developments have occurred in both hardware and software and have resulted in increasingly capable devices, advanced programming tools, and algorithmic innovations. The subset of artificial intelligence known as machine learning has emerged as one of the most transformative of these developments; it has major implications for space exploration and for improvements to the search for evidence of life beyond Earth. Those improvements include the integration of data across different scales and increased sensitivity to complex features in data, as well as the generation of adaptive strategies for sampling environments. In this article, the present and future nature of space exploration and astrobiological research is examined through the contextual lens of Viking and through the history and possible future of artificial intelligence.</p>","PeriodicalId":8645,"journal":{"name":"Astrobiology","volume":" ","pages":"150S-155S"},"PeriodicalIF":2.3,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148283073","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":"A Pressure-Supported Pneumatic Architecture for Robust Deep Drilling on Mars: Performance Modeling, Sizing, and Mission Integration.","authors":"Luis Phillipe Tosi, Marcel Veismann, Scott M Perl, Kristopher Sherrill, Scott Howe, Marcello Gori","doi":"10.1177/15311074261466550","DOIUrl":"https://doi.org/10.1177/15311074261466550","url":null,"abstract":"<p><p>Accessing the martian deep subsurface is a long-standing scientific priority for astrobiology, climate reconstruction, and planetary evolution, yet robotic drilling missions have historically been limited by wellbore instability, loss of working-fluid circulation, and the risk of irrecoverable tool entrapment. This work presents and evaluates a wireline, downhole-actuated pneumatic drilling architecture designed to directly mitigate these mission-ending risks through active wellbore pressure support and continuous cuttings removal within a single, sealed CO₂ circulation system. The proposed system combines a rotary-percussive bottomhole assembly with a deployable sealing membrane and a closed CO₂ pneumatic circuit that provides both mechanical support to the borehole wall and transport of generated cuttings to the surface. Reduced-order flow physics models are developed to capture compressible gas transport, particle entrainment, porous leak-off, junction losses, incompressible liquid tether flow, and phase-change thermodynamics. These models are assembled into section-wise drilling and cleanout cycles and integrated into a mission-level simulator that enforces realistic sol-level constraints on time, energy, battery usage, and working-fluid mass. Mission simulations demonstrate that cleanout operations dominate both energy and CO₂ mass budgets, establishing wellbore pressure support as a first-order design variable rather than a secondary constraint. Modest relaxation of the maintained back-pressure from an overburden-matched level to a derated fraction substantially reduces cleanout energy demand and idle leak-off penalties while preserving effective particle transport. Under an InSight/Mars Life Explorer-class mission envelope, the architecture exceeds a 30 m baseline depth target well within the nominal operational window, with favorable scaling toward ∼100 m depths through increased mission duration and resource allocation. By explicitly coupling drilling, cuttings removal, and wellbore stability within a single operational framework, this architecture targets the primary failure modes identified in deep martian subsurface access. The results indicate, at the concept and reduced-order sizing level, that pressure-supported pneumatic drilling may provide a scalable pathway for deep drilling on Mars and other low-pressure planetary bodies, while identifying the subsystem validation needed before flight-system viability can be assessed.</p>","PeriodicalId":8645,"journal":{"name":"Astrobiology","volume":"26 1_suppl","pages":"102S-149S"},"PeriodicalIF":2.3,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148444131","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":"How Viking Changed Science Communication.","authors":"Ann Druyan","doi":"10.1177/15311074261461733","DOIUrl":"10.1177/15311074261461733","url":null,"abstract":"<p><p>Fleeting public interest in the Viking mission inspired Carl Sagan to devise a new mode of science communication. One result was the <i>Cosmos</i> television series. Carl's global success offended many in the scientific community, and he was punished despite his solid research credentials. Almost 50 years later, the importance of public outreach by scientists seems to have reached greater professional acceptance. Key Words: Science communication-Viking-Cosmos-Mars-Public outreach. Astrobiology 26, 35S-37S.</p>","PeriodicalId":8645,"journal":{"name":"Astrobiology","volume":" ","pages":"35S-37S"},"PeriodicalIF":2.3,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148257162","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":"Viking's Heirs: The Rise of Planetary Flyers.","authors":"Shannah Withrow-Maser, Tove Ågren, Jonathan Bapst","doi":"10.1177/15311074261464016","DOIUrl":"10.1177/15311074261464016","url":null,"abstract":"<p><p>After Viking proved that long-term, meaningful scientific data could be sent reliably from the martian surface, the field fundamentally shifted. Its success reshaped how scientists and engineers formulated their research and planned future missions. In a similar way, the Ingenuity Mars Helicopter's demonstration of flight changes the paradigm, enabling new ways to do science on Mars and other planetary bodies. Rotorcraft enable increased range and coverage, access to hazardous terrain, and access to the atmospheric boundary layer. These capabilities expand the scientific reach of future missions. In astrobiology, aerial explorers could revolutionize the study of subsurface cavities and potential refuges for life, the detection of trace gases, high-resolution geological mapping, sampling or sample retrieval, and planetary protection. The technology driving improvements in both standalone rotorcraft and coordinated fleets of aerial vehicles is progressing quickly. As these systems mature, they are poised to become essential tools in planetary exploration.</p>","PeriodicalId":8645,"journal":{"name":"Astrobiology","volume":" ","pages":"86S-93S"},"PeriodicalIF":2.3,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148337544","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":"The Existing Frameworks of Delivery of Major Volatiles and the Feasibility of Mars-Mass Planetary Embryos as the Major Volatile Contributors to Bulk Silicate Earth.","authors":"Debjeet Pathak, Rajdeep Dasgupta","doi":"10.1177/15311074251365197","DOIUrl":"10.1177/15311074251365197","url":null,"abstract":"<p><p>The presence of major volatile elements-carbon, hydrogen, nitrogen, and sulfur-on Earth is critical for establishing life. The origin of these life-essential volatile elements (LEVEs) on Earth has been studied for many years. Here, we present a brief compilation of the prevailing ideas regarding volatile delivery to Earth and evaluate their origins, strengths, and weaknesses. Motivated by the fact that one model of LEVE delivery is via a giant impactor to Earth, we subsequently present a geochemical model aimed at understanding the possible volatile inventory and fractionation between the core, the silicate magma ocean (MO), and the atmosphere of a Mars-mass embryo. We looked at various end-member accretion scenarios of the embryo and their influence on the embryo's LEVE budget and the LEVE ratios. We varied various chemical (initial concentration of volatiles in the undifferentiated bodies and the oxygen fugacity [<i>f</i>O₂] of geochemical fractionation) and physical parameters (silicate-mass fraction of the accreting bodies, MO depth) to observe their effects on the absolute and relative LEVE budgets of the embryo. Our results show that an oxidizing condition (log<i>f</i> O₂ ≥ IW-1 [Iron-Wüstite]) is critical in establishing the relative LEVE budget of the embryo's MO, closer to that of present-day bulk silicate Earth. Furthermore, the accretion of larger bodies to form the Mars-mass embryo results in the closest match of the LEVE ratios to that of the present-day bulk silicate Earth (BSE). However, the absolute LEVE budget of the MO of Mars-mass embryo is depleted by at least 1-2 orders of magnitude compared with the BSE under all model calculation scenarios. In contrast, the CI-chondrite-normalized LEVE budget of the embryos's core, in many of the scenarios, especially from the reduced (<i>e.g.,</i> IW-2) bodies, overlaps or exceeds the present-day BSE estimate. We argue that for a Mars-mass, differentiated embryo, the cores provide a better prospect for LEVE delivery to proto-Earth, through core breakups and subsequent mixing in the MO or solid mantle. Future studies need to better assess whether the fractional retention of core materials in the silicate reservoir can match the present-day BSE LEVE budgets and how such a process compares with the LEVE delivery via less-processed primitive asteroids.</p>","PeriodicalId":8645,"journal":{"name":"Astrobiology","volume":" ","pages":"530-548"},"PeriodicalIF":2.3,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144871177","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":"Tectonics and Surface Environments on Early Earth.","authors":"Jun Korenaga","doi":"10.1089/ast.2024.0093","DOIUrl":"10.1089/ast.2024.0093","url":null,"abstract":"<p><p>The mode of tectonics that governed early Earth is controversial. This makes it challenging to infer surface environments relevant to the origin of life. The majority of the literature published in the past two decades was inclined to favor the appearance of plate tectonics sometime around the mid-Archean (∼3 Ga), with the operation of stagnant lid convection (or its variants) dominant in the earlier part of Earth's history. However, the available and increasing geological record from early Earth is actually equivocal, and there is no theoretical basis to prefer stagnant lid convection over plate tectonics. In fact, such a delayed onset of plate tectonics would inhibit the emergence of life in the Archean, let alone in the Hadean. On the contrary, rapid plate tectonics in the early Hadean, enabled by the fractional crystallization of a magma ocean, could quickly transform inclement young Earth into a habitable planet, with formation of multiple surface environments potentially conducive to abiogenesis.</p>","PeriodicalId":8645,"journal":{"name":"Astrobiology","volume":" ","pages":"565-577"},"PeriodicalIF":2.3,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143727636","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}