Origin and formation of planetary systems.

abstract：:Like all low- and moderate-mass stars, the Sun will burn as a red giant during its later evolution, generating of solar luminosities for some tens of millions of years. During this post-main sequence phase, the habitable (i.e., liquid water) thermal zone of our Solar System will lie in the region where Triton, Pluto-C...

journal_title：Astrobiology

authors： Stern SA

更新日期：2003-07-01 00:00:00

abstract：:Water is the fundamental molecule for life on Earth. Thus, the search for hibernating life-forms in waterless environments is an important research topic for astrobiology. To date, however, the organizational patterns containing microbial life in extremely dry places, such as the deserts of Earth, the Dry Valleys of A...

journal_title：Astrobiology

authors： Gómez Gómez JM,Medina J,Hochberg D,Mateo-Martí E,Martínez-Frías J,Rull F

更新日期：2014-07-01 00:00:00

abstract：:Photosynthesis on Earth can occur in a diversity of organisms in the photosynthetically active radiation (PAR) range of 10 nmol of photons m(-2) s(-1) to 8 mmol of photons m(-2) s(-1). Similar considerations would probably apply to photosynthetic organisms on Earth-like planets (ELPs) in the continuously habitable zon...

journal_title：Astrobiology

authors： Raven JA,Cockell CS

更新日期：2006-08-01 00:00:00

abstract：:The EPOXI Discovery Mission of Opportunity reused the Deep Impact flyby spacecraft to obtain spatially and temporally resolved visible photometric and moderate resolution near-infrared (NIR) spectroscopic observations of Earth. These remote observations provide a rigorous validation of whole-disk Earth model simulatio...

journal_title：Astrobiology

authors： Robinson TD,Meadows VS,Crisp D,Deming D,A'hearn MF,Charbonneau D,Livengood TA,Seager S,Barry RK,Hearty T,Hewagama T,Lisse CM,McFadden LA,Wellnitz DD

更新日期：2011-06-01 00:00:00

abstract：:Properties of avenues of transformation and their mutualism with forms of organization in dynamic systems are essential for understanding the evolution of prebiotic order. We have analyzed competition between two avenues of transformation in an A↔B system, using the simulation approach called BiADA (Biotic Abstract Du...

journal_title：Astrobiology

authors： Popa R,Cimpoiasu VM

更新日期：2013-05-01 00:00:00

abstract：:The NASA Astrobiology Roadmap provides guidance for research and technology development across the NASA enterprises that encompass the space, Earth, and biological sciences. The ongoing development of astrobiology roadmaps embodies the contributions of diverse scientists and technologists from government, universities...

journal_title：Astrobiology

authors： Des Marais DJ,Allamandola LJ,Benner SA,Boss AP,Deamer D,Falkowski PG,Farmer JD,Hedges SB,Jakosky BM,Knoll AH,Liskowsky DR,Meadows VS,Meyer MA,Pilcher CB,Nealson KH,Spormann AM,Trent JD,Turner WW,Woolf NJ,Yorke HW

更新日期：2003-07-01 00:00:00

abstract：:We describe a continuous high-pressure flow reactor designed to simulate the unforced convective interaction of hydrothermal solutions and ocean waters with submarine crust on early Earth-conditions appropriate to those that may have led to the onset of life. The experimental operating conditions are appropriate for i...

journal_title：Astrobiology

authors： Mielke RE,Russell MJ,Wilson PR,McGlynn SE,Coleman M,Kidd R,Kanik I

更新日期：2010-10-01 00:00:00

abstract：:The so-called Fermi paradox claims that if technological life existed anywhere else, we would see evidence of its visits to Earth--and since we do not, such life does not exist, or some special explanation is needed. Enrico Fermi, however, never published anything on this topic. On the one occasion he is known to have...

journal_title：Astrobiology

authors： Gray RH

更新日期：2015-03-01 00:00:00

abstract：:The five major mass extinctions identified in 1982 by Raup and Sepkoski have expanded to six, with the suggestion that the Permian-Triassic extinction was a double event. Is there a general explanation for great mass extinctions, or can they result from different triggers, or even from internal system instabilities? T...

journal_title：Astrobiology

authors： Alvarez W

更新日期：2003-04-01 00:00:00

abstract：:The bicarbonate-buffered anoxic vent waters at Chocolate Pots hot springs in Yellowstone National Park are 51-54°C, pH 5.5-6.0, and are very high in dissolved Fe(II) at 5.8-5.9 mg/L. The aqueous Fe(II) is oxidized by a combination of biotic and abiotic mechanisms and precipitated as primary siliceous nanophase iron ox...

journal_title：Astrobiology

authors： Parenteau MN,Jahnke LL,Farmer JD,Cady SL

更新日期：2014-06-01 00:00:00

abstract：:Jökulhlaups are terrestrial catastrophic outfloods, often triggered by subglacial volcanic eruptions. Similar volcano-ice interactions were likely important on Mars where magma/lava may have interacted with the planet's cryosphere to produce catastrophic floods. As a potential analogue to sediments deposited during ma...

journal_title：Astrobiology

authors： Warner NH,Farmer JD

更新日期：2010-06-01 00:00:00

abstract：:We revisit the validity of the presence of O(2) or O(3) in the atmosphere of a rocky planet as being a biosignature. Up to now, the false positive that has been identified applies to a planet during a hot greenhouse runaway, which is restricted to planets outside the habitable zone (HZ) of the star that are closer to ...

journal_title：Astrobiology

authors： Léger A,Fontecave M,Labeyrie A,Samuel B,Demangeon O,Valencia D

更新日期：2011-05-01 00:00:00

abstract：:The objective of the 2009 Mars Science Laboratory (MSL), which is planned to follow the Mars Exploration Rovers and the Phoenix lander to the surface of Mars, is to explore and assess quantitatively a site on Mars as a potential habitat for present or past life. Specific goals include an assessment of the past or pres...

journal_title：Astrobiology

authors： ten Kate IL,Canham JS,Conrad PG,Errigo T,Katz I,Mahaffy PR

更新日期：2008-06-01 00:00:00

abstract：:Short-term and long-term science plans were developed as part of the strategic planning process used by the Biologic Analog Science Associated with Lava Terrains (BASALT) science team to conduct two Mars-simulation missions investigating basalt habitability at terrestrial volcanic analog sites in 2016. A multidiscipli...

journal_title：Astrobiology

authors： Brady AL,Kobs Nawotniak SE,Hughes SS,Payler SJ,Stevens AH,Cockell CS,Elphic RC,Sehlke A,Haberle CW,Slater GF,Lim DSS

更新日期：2019-03-01 00:00:00

abstract：:Formation of microtubules in volcanic glass from subsurface environments has been widely attributed to in situ activity of micro-organisms, but evidence directly linking those structures to biological processes remains lacking. Investigations into the alternative possibility of abiotic tubule formation have been limit...

journal_title：Astrobiology

authors： McCollom TM,Donaldson C

更新日期：2019-01-01 00:00:00

abstract：:The articles associated with this Special Collection focus on the NASA BASALT (Biologic Analog Science Associated with Lava Terrains) Research Program, which aims at answering the question, "How do we support and enable scientific exploration during human Mars missions?" To answer this the BASALT team conducted scient...

journal_title：Astrobiology

authors： Lim DSS,Abercromby AFJ,Kobs Nawotniak SE,Lees DS,Miller MJ,Brady AL,Miller MJ,Mirmalek Z,Sehlke A,Payler SJ,Stevens AH,Haberle CW,Beaton KH,Chappell SP,Hughes SS,Cockell CS,Elphic RC,Downs MT,Heldmann JL

更新日期：2019-03-01 00:00:00

abstract：:The Dry Valleys of Antarctica are one of the coldest and driest environments on Earth with paleosols in selected areas that date to the emplacement of tills by warm-based ice during the Early Miocene. Cited as an analogue to the martian surface, the ability of the Antarctic environment to support microbial life-forms ...

journal_title：Astrobiology

authors： Hart KM,Szpak MT,Mahaney WC,Dohm JM,Jordan SF,Frazer AR,Allen CC,Kelleher BP

更新日期：2011-05-01 00:00:00

abstract：:The self-assembly of simple amphiphiles like fatty acids into cell-like membranous structures suggests that such structures were available on prebiotic Earth to support the origin of cellular life. However, the composition of primitive membranes remains unclear because the physical properties of the aqueous environmen...

journal_title：Astrobiology

authors： Maurer SE,Deamer DW,Boncella JM,Monnard PA

更新日期：2009-12-01 00:00:00

abstract：:In this work, we provide an answer to the question formulated by Albert Eschenmoser: "How would you envisage the bridge between potentially primordial geochemistry that had been disordered and one that gradually became self-organizing?" Analysis of the free-energy profiles of some of the key reactions leading to forma...

journal_title：Astrobiology

authors： Šponer JE,Šponer J,Di Mauro E

更新日期：2019-09-01 00:00:00

abstract：:Meaningful motion is an unambiguous biosignature, but because life in the Solar System is most likely to be microbial, the question is whether such motion may be detected effectively on the micrometer scale. Recent results on microbial motility in various Earth environments have provided insight into the physics and b...

journal_title：Astrobiology

authors： Nadeau J,Lindensmith C,Deming JW,Fernandez VI,Stocker R

更新日期：2016-10-01 00:00:00

abstract：:Several observations indicate that the cloud deck of the venusian atmosphere may provide a plausible refuge for microbial life. Having originated in a hot proto-ocean or been brought in by meteorites from Earth (or Mars), early life on Venus could have adapted to a dry, acidic atmospheric niche as the warming planet l...

journal_title：Astrobiology

authors： Schulze-Makuch D,Grinspoon DH,Abbas O,Irwin LN,Bullock MA

更新日期：2004-04-01 00:00:00

abstract：:Polymeric compounds similar to oligonucleotides are relevant to the origin of life and particularly to the concept of an RNA world. Although short oligomers of RNA can be synthesized nonenzymatically under laboratory conditions by second-order reactions in concentrated solutions, there is no consensus on how these pol...

journal_title：Astrobiology

authors： Kanavarioti A,Monnard PA,Deamer DW

更新日期：2001-10-01 00:00:00

abstract：:Microbial contamination of human-tended spacecraft is unavoidable, making the study of microbial growth under space conditions essential for the preservation of astronauts' health and equipment integrity. Previous studies suggested that spaceflight conditions, such as microgravity, cause a range of physiological micro...

journal_title：Astrobiology

authors： Garschagen LS,Mancinelli RL,Moeller R

更新日期：2019-10-01 00:00:00

abstract：:Small-scale terracing (microterracettes) is a surface geomorphic feature that recurs under a range of environmental settings, such as those existing in high to low temperature geothermal springs and evaporitic environments, through the single or combined action of physicochemical agents and microbiological processes. ...

journal_title：Astrobiology

authors： Barbieri R,Cavalazzi B

更新日期：2018-10-01 00:00:00

abstract：:Equilibrium adsorption isotherm data for the purine base adenine has been obtained on several prebiotically relevant minerals by frontal analysis using water as a mobile phase. Adenine is far displaced toward adsorption on pyrite (FeS2), quartz (SiO2), and pyrrhotite (FeS), but somewhat less for magnetite (Fe3O4) and ...

journal_title：Astrobiology

authors： Cohn CA,Hansson TK,Larsson HS,Sowerby SJ,Holm NG

更新日期：2001-01-01 00:00:00

abstract：:In spite of the spectacular developments in our understanding of the molecular basis that underlies biological phenomena, we still lack a generally agreed-upon definition of life, but this is not for want of trying. Life is an empirical concept; and, as suggested by the many unsuccessful efforts to define it, this tas...

journal_title：Astrobiology

authors： Tirard S,Morange M,Lazcano A

更新日期：2010-12-01 00:00:00

abstract：:Cyanobacteria and similar organisms produced most of the oxygen found in Earth's atmosphere, which implies that early photosynthetic organisms would have lived in an atmosphere that was rich in CO2 and poor in O2. We investigated the tolerance of several cyanobacteria to very high (>20 kPa) concentrations of atmospher...

journal_title：Astrobiology

authors： Thomas DJ,Sullivan SL,Price AL,Zimmerman SM

更新日期：2005-02-01 00:00:00

abstract：:A long-term goal of exoplanet studies is the identification and detection of biosignature gases. Beyond the most discussed biosignature gas O2, only a handful of gases have been considered in detail. In this study, we evaluate phosphine (PH3). On Earth, PH3 is associated with anaerobic ecosystems, and as such, it is a...

journal_title：Astrobiology

authors： Sousa-Silva C,Seager S,Ranjan S,Petkowski JJ,Zhan Z,Hu R,Bains W

更新日期：2020-02-01 00:00:00

abstract：:Recent discoveries about Europa--the probable existence of a sizeable ocean below its ice crust; the detection of hydrated sodium carbonates, among other salts; and the calculation of a net loss of sodium from the subsurface--suggest the existence of an alkaline ocean. Alkaline oceans (nicknamed "soda oceans" in analo...

journal_title：Astrobiology

authors： Kempe S,Kazmierczak J

更新日期：2002-04-01 00:00:00

abstract：UNLABELLED:Fluid inclusions trapped in ancient halite can contain a community of halophilic prokaryotes and eukaryotes that inhabited the surface brines from which the halite formed. Long-term survival of bacteria and archaea and preservation of DNA have been reported from halite, but little is known about the distribu...

journal_title：Astrobiology

authors： Wang J,Lowenstein TK,Fang X

更新日期：2016-06-01 00:00:00