Astrobiology and habitability studies in preparation for future Mars missions : Trends from investigating minerals, organics and biota

NARCIS (Netherlands)

Ehrenfreund, P.; Röling, W.F.M.; Thiel, C.S.; Quinn, R.; Sephton, M.A.; Stoker, C.; Kotler, J.M.; Direito, S.O.L.; Martins, Z.; Orzechowska, G.E.; Kidd, R.D.; Van Sluis, C.A.; Foing, B.H.

2011-01-01

Several robotic exploration missions will travel to Mars during this decade to investigate habitability and the possible presence of life. Field research at Mars analogue sites such as desert environments can provide important constraints for instrument calibration, landing site strategies and

Weathering Profiles in Phosphorus-Rich Rocks at Gusev Crater, Mars, Suggest Dissolution of Phosphate Minerals into Potentially Habitable Near-Neutral Waters.

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Adcock, Christopher T; Hausrath, Elisabeth M

2015-12-01

Abundant evidence indicates that significant surface and near-surface liquid water has existed on Mars in the past. Evaluating the potential for habitable environments on Mars requires an understanding of the chemical and physical conditions that prevailed in such aqueous environments. Among the geological features that may hold evidence of past environmental conditions on Mars are weathering profiles, such as those in the phosphorus-rich Wishstone-class rocks in Gusev Crater. The weathering profiles in these rocks indicate that a Ca-phosphate mineral has been lost during past aqueous interactions. The high phosphorus content of these rocks and potential release of phosphorus during aqueous interactions also make them of astrobiological interest, as phosphorus is among the elements required for all known life. In this work, we used Mars mission data, laboratory-derived kinetic and thermodynamic data, and data from terrestrial analogues, including phosphorus-rich basalts from Idaho, to model a conceptualized Wishstone-class rock using the reactive transport code CrunchFlow. Modeling results most consistent with the weathering profiles in Wishstone-class rocks suggest a combination of chemical and physical erosion and past aqueous interactions with near-neutral waters. The modeling results also indicate that multiple Ca-phosphate minerals are likely in Wishstone-class rocks, consistent with observations of martian meteorites. These findings suggest that Gusev Crater experienced a near-neutral phosphate-bearing aqueous environment that may have been conducive to life on Mars in the past. Mars-Gusev Crater-Wishstone-Reactive transport modeling-CrunchFlow-Aqueous interactions-Neutral pH-Habitability.

Fluid Expulsion, Habitability, and the Search for Life on Mars

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Oehler, Dorothy Z.; Allen, Carlton C.

2012-01-01

Habitability assessments are critical for identifying settings in which potential biosignatures could exist in quantities large enough to be detected by rovers. Habitability depends on 1) the potential for long-lived liquid water, 2) conditions affording protection from surface processes destructive to organic biomolecules, and 3) a source of renewing nutrients and energy. Of these criteria, the latter is often overlooked. Here we present an analysis of a large "ghost" crater in northern Chryse Planitia [1] that appears to have satisfied each of these requirements, with several processes providing potential sources of nutrient/energy renewal [1-2]. This analysis can serve as a model for identifying other localities that could provide similarly favorable settings in which to seek evidence of life on Mars.

Mars Habitability, Biosignature Preservation, and Mission Support

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Oehler, Dorothy Z.; Allen, Carlton C.

2014-01-01

Our work has elucidated a new analog for the formation of giant polygons on Mars, involving fluid expulsion in a subaqueous environment. That work is based on three-dimensional (3D) seismic data on Earth that illustrate the mud volcanoes and giant polygons that result from sediment compaction in offshore settings. The description of this process has been published in the journal Icarus, where it will be part of a special volume on Martian analogs. These ideas have been carried further to suggest that giant polygons in the Martian lowlands may be the signature of an ancient ocean and, as such, could mark a region of enhanced habitability. A paper describing this hypothesis has been published in the journal Astrobiology.

Make peak flow a habit

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Asthma - make peak flow a habit; Reactive airway disease - peak flow; Bronchial asthma - peak flow ... 2014:chap 55. National Asthma Education and Prevention Program website. How to use a peak flow meter. ...

Habitability constraints/objectives for a Mars manned mission: internal architecture considerations.

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Winisdoerffer, F; Soulez-Larivière, C

1992-01-01

It is generally accepted that high quality internal environment shall strongly support crew's adaptation and acceptance to situation of long isolation and confinement. Thus, this paper is an attempt to determine to which extent the resulting stress corresponding to the anticipated duration of a trip to Mars (1 and a half years to 2 and a half years) could be decreased when internal architecture of the spacecraft is properly designed. It is assumed that artificial gravity shall be available on board the Mars spacecraft. This will of course have a strong impact on internal architecture as far as a 1-g oriented design will become mandatory, at least in certain inhabited parts of the spacecraft. The review of usual Habitability functions is performed according to the peculiarities of such an extremely long mission. A particular attention is paid to communications issues and the need for privacy. The second step of the paper addresses internal architecture issues through zoning analyses. Common, Service and Personal zones need to be adapted to the constraints associated with the extremely long duration of the mission. Furthermore, due to the nature of the mission itself (relative autonomy, communication problems, monotony) and the type of selected crew (personalities, group structure) the implementation of a "fourth zone", so-called "recreational" zone, seems to be needed. This zoning analysis is then translated into some internal architecture proposals, which are discussed and illustrated. This paper is concluded by a reflection on habitability and recommendations on volumetric requirements. Some ideas to validate proposed habitability items through simulation are also discussed.

Clays and Carbonates in a Groundwater-Fed 3.8 Ga Martian Lake: Insights to Subsurface Habitability on Mars

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Michalski, Joseph; Niles, Paul

2015-01-01

On Earth, the deep biosphere remains a largely unexplored, but clearly important carbon reservoir. Results from some uplifted central peaks in craters on Mars indicate that substantial carbon was also present at depth and might have helped sustain a deep biosphere. In fact, many factors relevant to deep biosphere habitability are more favorable on Mars than on Earth (e.g. porosity of the crust, geothermal gradient). Future exploration of Mars should include landing sites where materials have been exhumed from depth by meteor impact or basins where subsurface fluids have emerged, carrying clues to subsurface habitability. One of the most astrobiologically interesting sites on Mars McLaughlin Crater, a 93 km-diameter impact crater that formed approximately 4 b.y. ago. On the floor of the crater is a stratigraphic section of subhorizontal, layered sedimentary rocks with strong spectroscopic evidence for Fe-rich clay minerals and Mg-rich carbonates, which we interpret as ancient lacustrine deposits. The fluids that formed these materials likely originated in the subsurface, based on the paucity of channels leading into the crater basin and the fact that this is one of the deepest basins on Mars - a good candidate to have experienced upwelling of subsurface fluids. Therefore, the deposits within McLaughlin crater provide insight into subsurface processes on Mars. In this presentation, we will discuss the habitability of the martian subsurface as well as the geology of McLaughlin Crater and the possibility to detect biomarkers at that site with a future landed mission.

Exploring Mars for Evidence of Habitable Environments and Life

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DesMarais, David J.

2014-01-01

The climate of Mars has been more similar to that of Earth than has the climate of any other planet in our Solar System. But Mars still provides a valuable alternative example of how planetary processes and environments can affect the potential presence of life elsewhere. For example, although Mars also differentiated very early into a core, mantle and crust, it then evolved mostly if not completely without plate tectonics and has lost most of its early atmosphere. The Martian crust has been more stable than that of Earth, thus it has probably preserved a more complete record of its earliest history. Orbital observations determined that near-surface water was once pervasive. Orbiters have identified the following diverse aqueous sedimentary deposits: layered phyllosilicates, phyllosilicates in intracrater fans, plains sediments potentially harboring evaporitic minerals, deep phyllosilicates, carbonate-bearing deposits, intracrater clay-sulfate deposits, Meridiani-type layered deposits, valles-type layered deposits, hydrated silica-bearing deposits, and gypsum plains. These features, together with evidence of more vigorous past geologic activity, indicate that early climates were wetter and perhaps also somewhat warmer. The denser atmosphere that was required for liquid water to be stable on the surface also provided more substantial protection from radiation. Whereas ancient climates might have favored habitable environments at least in some localities, clearly much of the Martian surface for most of its history has been markedly less favorable for life. The combination of dry conditions, oxidizing surface environments and typically low rates of sedimentation are not conducive to the preservation of evidence of ancient environments and any biota. Thus a strategy is required whereby candidate sites are first identified and then characterized for their potential to preserve evidence of past habitable environments. Rovers are then sent to explore the most promising

In Situ Strategy of the 2011 Mars Science Laboratory to Investigate the Habitability of Ancient Mars

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Mahaffy, Paul R.

2011-01-01

The ten science investigations of the 2011 Mars Science Laboratory (MSL) Rover named "Curiosity" seek to provide a quantitative assessment of habitability through chemical and geological measurements from a highly capable robotic' platform. This mission seeks to understand if the conditions for life on ancient Mars are preserved in the near-surface geochemical record. These substantial payload resources enabled by MSL's new entry descent and landing (EDL) system have allowed the inclusion of instrument types nevv to the Mars surface including those that can accept delivered sample from rocks and soils and perform a wide range of chemical, isotopic, and mineralogical analyses. The Chemistry and Mineralogy (CheMin) experiment that is located in the interior of the rover is a powder x-ray Diffraction (XRD) and X-ray Fluorescence (XRF) instrument that provides elemental and mineralogical information. The Sample Analysis at Mars (SAM) suite of instruments complements this experiment by analyzing the volatile component of identically processed samples and by analyzing atmospheric composition. Other MSL payload tools such as the Mast Camera (Mastcam) and the Chemistry & Camera (ChemCam) instruments are utilized to identify targets for interrogation first by the arm tools and subsequent ingestion into SAM and CheMin using the Sample Acquisition, Processing, and Handling (SA/SPaH) subsystem. The arm tools include the Mars Hand Lens Imager (MAHLI) and the Chemistry and Alpha Particle X-ray Spectrometer (APXX). The Dynamic Albedo of Neutrons (DAN) instrument provides subsurface identification of hydrogen such as that contained in hydrated minerals

Exploration of the Habitability of Mars with the SAM Suite Investigation on the 2009 Mars Science Laboratory

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Mahaffy, P. R.; Cabane, M.; Webster, C. R.

2008-01-01

The 2009 Mars Science Laboratory (MSL) with a substantially larger payload capability that any other Mars rover, to date, is designed to quantitatively assess a local region on Mars as a potential habitat for present or past life. Its goals are (1) to assess past or present biological potential of a target environment, (2) to characterize geology and geochemistry at the MSL landing site, and (3) to investigate planetary processes that influence habitability. The Sample Analysis at Mars (SAM) Suite, in its final stages of integration and test, enables a sensitive search for organic molecules and chemical and isotopic analysis of martian volatiles. MSL contact and remote surface and subsurface survey Instruments establish context for these measurements and facilitate sample identification and selection. The SAM instruments are a gas chromatograph (GC), a mass spectrometer (MS), and a tunable laser spectrometer (TLS). These together with supporting sample manipulation and gas processing devices are designed to analyze either the atmospheric composition or gases extracted from solid phase samples such as rocks and fines. For example, one of the core SAM experiment sequences heats a small powdered sample of a Mars rock or soil from ambient to -1300 K in a controlled manner while continuously monitoring evolved gases. This is followed by GCMS analysis of released organics. The general chemical survey is complemented by a specific search for molecular classes that may be relevant to life including atmospheric methane and its carbon isotope with the TLS and biomarkers with the GCMS.

Habitability during long-duration space missions - Key issues associated with a mission to Mars

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Stuster, Jack

1989-01-01

Isolation and confinement conditions similar to those of a long-duration mission to Mars are examined, focusing on 14 behavioral issues with design implications. Consideration is given to sleep, clothing, exercise, medical support, personal hygiene, food preparation, group interaction, habitat aesthetics, outside communications, recreational opportunities, privacy, waste disposal, onboard training, and the microgravity environment. The results are used to develop operational requirements and habitability design guidelines for interplanetary spacecraft.

Trajectories of martian habitability.

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Cockell, Charles S

2014-02-01

Beginning from two plausible starting points-an uninhabited or inhabited Mars-this paper discusses the possible trajectories of martian habitability over time. On an uninhabited Mars, the trajectories follow paths determined by the abundance of uninhabitable environments and uninhabited habitats. On an inhabited Mars, the addition of a third environment type, inhabited habitats, results in other trajectories, including ones where the planet remains inhabited today or others where planetary-scale life extinction occurs. By identifying different trajectories of habitability, corresponding hypotheses can be described that allow for the various trajectories to be disentangled and ultimately a determination of which trajectory Mars has taken and the changing relative abundance of its constituent environments.

Hints of Habitable Environments on Mars Challenge Our Studies of Mars-Analog Sites on Earth

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desMarais, David J

2009-01-01

Life as we know it requires water with a chemical activity (alpha) >or approx.0.6 and sources of nutrients and useful energy. Some biota can survive even if favorable conditions occur only intermittently, but the minimum required frequency of occurrences is poorly understood. Recent discoveries have vindicated the Mars exploration strategy to follow the water. Mars Global Surveyor s Thermal Emission Spectrometer (TES) found coarse-grained hematite at Meridiani Planum. Opportunity rover confirmed this and also found evidence of ancient sulfate-rich playa lakes and near-surface groundwater. Elsewhere, TES found evidence of evaporitic halides in topographic depressions. But alpha might not have approached 0.6 in these evaporitic sulfate- and halide-bearing waters. Mars Express (MEX) and Mars Reconnaissance Orbiter (MRO) found extensive sulfate evaporites in Meridiani and Valles Marineris. MEX found phyllosilicates at several sites, most notably Mawrth Valles and Nili Fossae. MRO's CRISM near-IR mapper extended the known diversity and geographic distribution of phyllosilicates to include numerous Noachian craters. Phyllosilicates typically occur at the base of exposed ancient rock sections or in sediments in early Hesperian craters. It is uncertain whether the phyllosilicates developed in surface or subsurface aqueous environments and how long aqueous conditions persisted. Spirit rover found remarkably pure ferric sulfate, indicating oxidation and transport of Fe and S, perhaps in fumaroles or hot springs. Spirit also found opaline silica, consistent with hydrothermal activity. CRISM mapped extensive silica deposits in the Valles Marineris region, consistent with aqueous weathering and deposition. CRISM also found ultramafic rocks and magnesite at Nili Fossae, consistent with serpentinization, a process that can sustain habitable environments on Earth. The report of atmospheric methane implies subsurface aqueous conditions. A working hypothesis is that aqueous

Characterizing of a Mid-Latitude Ice-Rich Landing Site on Mars to Enable in Situ Habitability Studies

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Heldmann, J.; Schurmeier, L. R.; Wilhelm, M.; Stoker, C.; McKay, C.; Davila, A.; Marinova, M.; Karcz, J.; Smith, H.

2012-01-01

We suggest an ice-rich landing site at 188.5E 46.16N within Amazonis Planitia as a candidate location to support a Mars lander mission equipped to study past habitability and regions capable of preserving the physical and chemical signs of life and organic matter. Studies of the ice-rich subsurface on Mars are critical for several reasons. The subsurface environment provides protection from radiation to shield organic and biologic compounds from destruction. The ice-rich substrate is also ideal for preserving organic and biologic molecules and provides a source of H2O for biologic activity. Examination of martian ground ice can test several hypotheses such as: 1) whether ground ice supports habitable conditions, 2) that ground ice can preserve and accumulate organic compounds, and 3) that ice contains biomolecules evident of past or present biological activity on Mars. This Amazonis site, located near the successful Viking Lander 2, shows indirect evidence of subsurface ice (ubiquitous defined polygonal ground, gamma ray spectrometer hydrogen signature, and numerical modeling of ice stability) and direct evidence of exposed subsurface ice. This site also provides surface conditions favorable to a safe landing including no boulders, low rock density, minimal rough topography, and few craters.

Volcanogenic Fluvial-Lacustrine Environments in Iceland and Their Utility for Identifying Past Habitability on Mars

Directory of Open Access Journals (Sweden)

Claire Cousins

2015-02-01

Full Text Available The search for once-habitable locations on Mars is increasingly focused on environments dominated by fluvial and lacustrine processes, such as those investigated by the Mars Science Laboratory Curiosity rover. The availability of liquid water coupled with the potential longevity of such systems renders these localities prime targets for the future exploration of Martian biosignatures. Fluvial-lacustrine environments associated with basaltic volcanism are highly relevant to Mars, but their terrestrial counterparts have been largely overlooked as a field analogue. Such environments are common in Iceland, where basaltic volcanism interacts with glacial ice and surface snow to produce large volumes of meltwater within an otherwise cold and dry environment. This meltwater can be stored to create subglacial, englacial, and proglacial lakes, or be released as catastrophic floods and proglacial fluvial systems. Sedimentary deposits produced by the resulting fluvial-lacustrine activity are extensive, with lithologies dominated by basaltic minerals, low-temperature alteration assemblages (e.g., smectite clays, calcite, and amorphous, poorly crystalline phases (basaltic glass, palagonite, nanophase iron oxides. This paper reviews examples of these environments, including their sedimentary deposits and microbiology, within the context of utilising these localities for future Mars analogue studies and instrument testing.

Volcanogenic fluvial-lacustrine environments in iceland and their utility for identifying past habitability on Mars.

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Cousins, Claire

2015-02-16

The search for once-habitable locations on Mars is increasingly focused on environments dominated by fluvial and lacustrine processes, such as those investigated by the Mars Science Laboratory Curiosity rover. The availability of liquid water coupled with the potential longevity of such systems renders these localities prime targets for the future exploration of Martian biosignatures. Fluvial-lacustrine environments associated with basaltic volcanism are highly relevant to Mars, but their terrestrial counterparts have been largely overlooked as a field analogue. Such environments are common in Iceland, where basaltic volcanism interacts with glacial ice and surface snow to produce large volumes of meltwater within an otherwise cold and dry environment. This meltwater can be stored to create subglacial, englacial, and proglacial lakes, or be released as catastrophic floods and proglacial fluvial systems. Sedimentary deposits produced by the resulting fluvial-lacustrine activity are extensive, with lithologies dominated by basaltic minerals, low-temperature alteration assemblages (e.g., smectite clays, calcite), and amorphous, poorly crystalline phases (basaltic glass, palagonite, nanophase iron oxides). This paper reviews examples of these environments, including their sedimentary deposits and microbiology, within the context of utilising these localities for future Mars analogue studies and instrument testing.

Habitability Assessment at Gale Crater: Implications from Initial Results

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Conrad, Pamela G.; Archer, D.; Atreya, S.; Blake, D.; Coll, P.; delaTorre, M.; Edgett, K.; Eigenbrode, J.; Fisk, M.; Freissent, C.;

Mission to Mars: Plans and concepts for the first manned landing

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Oberg, J. E.

The manned exploration and settlement of Mars is discussed. The topics considered include: the rationale for a manned landing; spaceships and propulsion for getting to Mars; human factors such as psychological stress, the effects of prolonged weightlessness, and radiation dangers; the return from Mars; site selection and relevant criteria; scientific problems that can be studied by landing men on Mars. Also addressed are economic resources of air and water on Mars and their relevance for transportation and mission planning; the exploration and utilization of Phobos and Deimos; cost factors; the possibilities of the Russians' going to Mars; political and social issues; colonies on Mars; and manipulation of the Martian environment to make it more habitable.

Habitable Mars Ascent Vehicle (MAV) Concept. [Mars Ascent Vehicle (MAV) Layout and Configuration: 6-Crew, Habitable, Nested Tank Concept

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Dang, Victor; Rucker, Michelle

2013-01-01

NASA's ultimate goal is the human exploration of Mars. Among the many difficult aspects of a trip to Mars is the return mission that would transport the astronauts from the Martian surface back into Mars orbit. One possible conceptual design to accomplish this task is a two-stage Mars Ascent Vehicle (MAV). In order to assess this design, a general layout and configuration for the spacecraft must be developed. The objective of my internship was to model a conceptual MAV design to support NASA's latest human Mars mission architecture trade studies, technology prioritization decisions, and mass, cost, and schedule estimates.

The Sustainability of Habitability on Terrestrial Planets: Insights, Questions, and Needed Measurements from Mars for Understanding the Evolution of Earth-Like Worlds

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Ehlmann, B. L.; Anderson, F. S.; Andrews-Hanna, J.; Catling, D. C.; Christensen, P. R.; Cohen, B. A.; Dressing, C. D.; Edwards, C. S.; Elkins-Tanton, L. T.; Farley, K. A.;

Habitable Trinity

Directory of Open Access Journals (Sweden)

James M. Dohm

2015-01-01

Full Text Available Habitable Trinity is a newly proposed concept of a habitable environment. This concept indicates that the coexistence of an atmosphere (consisting largely of C and N, an ocean (H and O, and a landmass (supplier of nutrients accompanying continuous material circulation between these three components driven by the Sun is one of the minimum requirements for life to emerge and evolve. The life body consists of C, O, H, N and other various nutrients, and therefore, the presence of water, only, is not a sufficient condition. Habitable Trinity environment must be maintained to supply necessary components for life body. Our Habitable Trinity concept can also be applied to other planets and moons such as Mars, Europa, Titan, and even exoplanets as a useful index in the quest for life-containing planetary bodies.

Natural fumarolic alteration of fluorapatite, olivine, and basaltic glass, and implications for habitable environments on Mars.

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Hausrath, Elisabeth M; Tschauner, Oliver

2013-11-01

Fumaroles represent a very important potential habitat on Mars because they contain water and nutrients. Global deposition of volcanic sulfate aerosols may also have been an important soil-forming process affecting large areas of Mars. Here we identify alteration from the Senator fumarole, northwest Nevada, USA, and in low-temperature environments near the fumarole to help interpret fumarolic and acid vapor alteration of rocks and soils on Mars. We analyzed soil samples and fluorapatite, olivine, and basaltic glass placed at and near the fumarole in in situ mineral alteration experiments designed to measure weathering under natural field conditions. Using synchrotron X-ray diffraction, we clearly observe hydroxyl-carbonate-bearing fluorapatite as a fumarolic alteration product of the original material, fluorapatite. The composition of apatites as well as secondary phosphates has been previously used to infer magmatic conditions as well as fumarolic conditions on Mars. To our knowledge, the observations reported here represent the first documented instance of formation of hydroxyl-carbonate-bearing apatite from fluorapatite in a field experiment. Retreat of olivine surfaces, as well as abundant NH4-containing minerals, was also characteristic of fumarolic alteration. In contrast, alteration in the nearby low-temperature environment resulted in formation of large pits on olivine surfaces, which were clearly distinguishable from the fumarolic alteration. Raman signatures of some fumarolically impacted surfaces are consistent with detection of the biological molecules chlorophyll and scytenomin, potentially useful biosignatures. Observations of altered minerals on Mars may therefore help identify the environment of formation and understand the aqueous history and potential habitability of that planet.

Chromatographic, Spectroscopic and Mass Spectrometric Approaches for Exploring the Habitability of Mars in 2012 and Beyond with the Curiosity Rover

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Mahaffy, Paul

2012-01-01

The Sample Analysis at Mars (SAM) suite of instruments on the Curiosity Rover of Mars Science Laboratory Mission is designed to provide chemical and isotopic analysis of organic and inorganic volatiles for both atmospheric and solid samples. The goals of the science investigation enabled by the gas chromatograph mass spectrometer and tunable laser spectrometer instruments of SAM are to work together with the other MSL investigations is to quantitatively assess habitability through a series of chemical and geological measurements. We describe the multi-column gas chromatograph system employed on SAM and the approach to extraction and analysis of organic compounds that might be preserved in ancient martian rocks.

Make Handwashing a Habit (A Minute of Health with CDC)

Centers for Disease Control (CDC) Podcasts

2016-10-13

Regular handwashing helps prevent the spread of potentially harmful germs. This podcast discusses the importance of making proper handwashing (with soap and water) a regular habit.  Created: 10/13/2016 by MMWR.   Date Released: 10/13/2016.

Indigenous Fixed Nitrogen on Mars: Implications for Habitability

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Stern, J. C.; Sutter, B.; Navarro-Gonzalez, R.; McKay, C. P.; Freissinet, C.; Archer, D., Jr.; Eigenbrode, J. L.; Mahaffy, P. R.; Conrad, P. G.

2015-12-01

Nitrate has been detected in Mars surface sediments and aeolian deposits by the Sample Analysis at Mars (SAM) instrument on the Mars Science Laboratory Curiosity rover (Stern et al., 2015). This detection is significant because fixed nitrogen is necessary for life, a requirement that drove the evolution of N-fixing metabolism in life on Earth. The question remains as to the extent to which a primitive N cycle ever developed on Mars, and whether N is currently being deposited on the martian surface at a non-negligible rate. It is also necessary to consider processes that could recycle oxidized N back into the atmosphere, and how these processes may have changed the soil inventory of N over time. The abundance of fixed nitrogen detected as NO from thermal decomposition of nitrate is consistent with both delivery of nitrate via impact generated thermal shock early in martian history and dry deposition from photochemistry of thermospheric NO, occurring in the present. Processes that could recycle N back into the atmosphere may include nitrate reduction by Fe(II) in aqueous environments on early Mars, impact decomposition, and/or UV photolysis. In order to better understand the history of nitrogen fixation on Mars, we look to cycling of N in Mars analog environments on Earth such as the Atacama Desert and the Dry Valleys of Antarctica. In particular, we examine the ratio of nitrate to perchlorate (NO3-/ClO4-) in these areas compared to those calculated from data acquired on Mars.

Habitability: Where to look for life? Halophilic habitats: Earth analogs to study Mars habitability

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Gómez, F.; Rodríguez-Manfredi, J. A.; Rodríguez, N.; Fernández-Sampedro, M.; Caballero-Castrejón, F. J.; Amils, R.

2012-08-01

Oxidative stress, high radiation doses, low temperature and pressure are parameters which made Mars's surface adverse for life. Those conditions found on Mars surface are harsh conditions for life to deal with. Life, as we know it on Earth, needs several requirements for its establishment but, the only "sine qua nom" element is water. Extremophilic microorganisms widened the window of possibilities for life to develop in the universe, and as a consequence on Mars. Recently reported results in extreme environments indicate the possibility of presence of "oasys" for life in microniches due to water deliquescence in salts deposits. The compilation of data produced by the ongoing missions (Mars Global Surveyor, Mars Odyssey, Mars Express and Mars Exploration Rover Opportunity) offers a completely different view from that reported by Viking missions: signs of an early wet Mars and rather recent volcanic activity. The discovery of important accumulations of sulfates, and the existence of iron minerals like jarosite, goethite and hematite in rocks of sedimentary origin has allowed specific terrestrial models related with this type of mineralogy to come into focus. Río Tinto (Southwestern Spain, Iberian Pyritic Belt) is an extreme acidic environment, product of the chemolithotrophic activity of microorganisms that thrive in the massive pyrite-rich deposits of the Iberian Pyritic Belt. The high concentration of ferric iron and sulfates, products of the metabolism of pyrite, generate a collection of minerals, mainly gypsum, jarosite, goethite and hematites, all of which have been detected in different regions of Mars. Some particular protective environments or elements could house organic molecules or the first bacterial life forms on Mars surface. Terrestrial analogs could help us to afford its comprehension. We are reporting here some preliminary studies about endolithic niches inside salt deposits used by phototrophs for taking advantage of sheltering particular light

Palmer Quest: A Feasible Nuclear Fission "Vision Mission" to the Mars Polar Caps

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Carsey, F. D.; Beegle, L. W.; Nakagawa, R.; Elliott, J. O.; Matthews, J. B.; Coleman, M. L.; Hecht, M. H.; Ivaniov, A. B.; Head, J. W.; Milkovich, S.

2005-01-01

We are engaged in a NASA Vision Mission study, called Palmer Quest after the American Antarctic explorer Nathaniel Palmer, to assess the presence of life and evaluate the habitability of the basal domain of the Mars polar caps. We address this goal through four objectives: 1. Determine the presence of amino acids, nutrients, and geochemical heterogeneity in the ice sheet. 2. Quantify and characterize the provenance of the amino acids in Mars ice. 3. Assess the stratification of outcropped units for indications of habitable zones. 4. Determine the accumulation of ice, mineralogic material, and amino acids in Mars ice caps over the present epoch. Because of the defined scientific goal for the vision mission, the Palmer Quest focus is astrobiological; however, the results of the study make us optimistic that aggressive multi-platform in-situ missions that address a wide range of objectives, such as climate change, can be supported by variations of the approach used on this mission. Mission Overview: The Palmer Quest baseline

Planetary Habitability

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Kasting, James F.

1997-01-01

This grant was entitled 'Planetary Habitability' and the work performed under it related to elucidating the conditions that lead to habitable, i.e. Earth-like, planets. Below are listed publications for the past two and a half years that came out of this work. The main thrusts of the research involved: (1) showing under what conditions atmospheric O2 and O3 can be considered as evidence for life on a planet's surface; (2) determining whether CH4 may have played a role in warming early Mars; (3) studying the effect of varying UV levels on Earth-like planets around different types of stars to see whether this would pose a threat to habitability; and (4) studying the effect of chaotic obliquity variations on planetary climates and determining whether planets that experienced such variations might still be habitable. Several of these topics involve ongoing research that has been carried out under a new grant number, but which continues to be funded by NASA's Exobiology program.

The Mineralogical and Chemical Case for Habitability at Yellowknife Bay, Gale Crater, Mars

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Blake, David Frederick; Vaniman, David; Grotzinger, John P.; Conrad, Pamela Gales; Ming, Douglas W.; Bish, David L.; Farmer, Jack D.; Bristow, Thomas

2013-01-01

Sediments of the Yellowknife Bay formation (Gale crater) include the Sheepbed member, a mudstone cut by light-toned veins. Two drill samples, John Klein and Cumberland, were collected and analyzed by the CheMin XRD/XRF instrument and the Sample Analysis at Mars (SAM) evolved gas and isotopic analysis suite of instruments. Drill cuttings were also analyzed by the Alpha Particle X-ray Spectrometer (APXS) for bulk composition. The CheMin XRD analysis shows that the mudstone contains basaltic minerals (Fe-forsterite, augite, pigeonite, plagioclase), as well as Fe-oxide/hydroxides, Fe-sulfides, amorphous materials, and trioctahedral phyllosilicates. SAM evolved gas analysis of higher-temperature OH matches the CheMin XRD estimate of 20% clay minerals in the mudstone. The light-toned veins contain Ca-sulfates; anhydrite and bassanite are detected by XRD but gypsum is also indicated from Mastcam spectral mapping. These sulfates appear to be almost entirely restricted to late-diagenetic veins. The sulfate content of the mudstone matrix itself is lower than other sediments analyzed on Mars. The presence of phyllosilicates indicates that the activity of water was high during their formation and/or transport and deposition (should they have been detrital). Lack of chlorite places limits on the maximum temperature of alteration (likely habitable environment: Aqueous deposition at clement conditions of P, T, pH, Eh and ionic strength, plus the availability of sources of chemical energy.

Recent Accomplishments in Mars Exploration: The Rover Perspective

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McLennan, S. M.; McSween, H. Y.

2018-04-01

Mobile rovers have revolutionized our understanding of Mars geology by identifying habitable environments and addressing critical questions related to Mars science. Both the advances and limitations of rovers set the scene for Mars Sample Return.

Moon-Mars Analogue Mission (EuroMoonMars 1 at the Mars Desert Research Station)

Science.gov (United States)

Lia Schlacht, Irene; Voute, Sara; Irwin, Stacy; Foing, Bernard H.; Stoker, Carol R.; Westenberg, Artemis

The Mars Desert Research Station (MDRS) is situated in an analogue habitat-based Martian environment, designed for missions to determine the knowledge and equipment necessary for successful future planetary exploration. For this purpose, a crew of six people worked and lived together in a closed-system environment. They performed habitability experiments within the dwelling and conducted Extra-Vehicular Activities (EVAs) for two weeks (20 Feb to 6 Mar 2010) and were guided externally by mission support, called "Earth" within the simulation. Crew 91, an international, mixed-gender, and multidisciplinary group, has completed several studies during the first mission of the EuroMoonMars campaign. The crew is composed of an Italian designer and human factors specialist, a Dutch geologist, an American physicist, and three French aerospace engineering students from Ecole de l'Air, all with ages between 21 and 31. Each crewmember worked on personal research and fulfilled a unique role within the group: commander, executive officer, engineer, health and safety officer, scientist, and journalist. The expedition focused on human factors, performance, communication, health and safety pro-tocols, and EVA procedures. The engineers' projects aimed to improve rover manoeuvrability, far-field communication, and data exchanges between the base and the rover or astronaut. The crew physicist evaluated dust control methods inside and outside the habitat. The geologist tested planetary geological sampling procedures. The crew designer investigated performance and overall habitability in the context of the Mars Habitability Experiment from the Extreme-Design group. During the mission the crew also participated in the Food Study and in the Ethospace study, managed by external groups. The poster will present crew dynamics, scientific results and daily schedule from a Human Factors perspective. Main co-sponsors and collaborators: ILEWG, ESA ESTEC, NASA Ames, Ecole de l'Air, SKOR, Extreme

Human Factors and Habitability Challenges for Mars Missions

Science.gov (United States)

Whitmore, Mihriban

2015-01-01

As NASA is planning to send humans deeper into space than ever before, adequate crew health and performance will be critical for mission success. Within the NASA Human Research Program (HRP), the Space Human Factors and Habitability (SHFH) team is responsible for characterizing the risks associated with human capabilities and limitations with respect to long-duration spaceflight, and for providing mitigations (e.g., guidelines, technologies, and tools) to promote safe, reliable and productive missions. SHFH research includes three domains: Advanced Environmental Health (AEH), Advanced Food Technology (AFT), and Space Human Factors Engineering (SHFE). The AEH portfolio focuses on understanding the risk of microbial contamination of the spacecraft and on the development of standards for exposure to potential toxins such as chemicals, bacteria, fungus, and lunar/Martian dust. The two risks that the environmental health project focuses on are adverse health effects due to changes in host-microbe interactions, and risks associated with exposure to dust in planetary surface habitats. This portfolio also proposes countermeasures to these risks by making recommendations that relate to requirements for environmental quality, foods, and crew health on spacecraft and space missions. The AFT portfolio focuses on reducing the mass, volume, and waste of the entire integrated food system to be used in exploration missions, and investigating processing methods to extend the shelf life of food items up to five years, while assuring that exploration crews will have nutritious and palatable foods. The portfolio also delivers improvements in both the food itself and the technologies for storing and preparing it. SHFE sponsors research to establish human factors and habitability standards and guidelines in five risk areas, and provides improved design concepts for advanced crew interfaces and habitability systems. These risk areas include: Incompatible vehicle/habitat design

The Human Dimension -- Habitability AustroMars 2006

Science.gov (United States)

Haeuplik, S.; Imhof, B.

2007-10-01

Whether a cellular phone, a laptop computer or a spacecraft there are always two sides to an interface: a system side and a human side, and thus two sets of goals must be defined. In spaceflight, these two set of goals are defined for the technical system and the human system within its full scope. The human dimension is vital for a human mission if the mission should be successful. As the technical system is, compared with the human system less complex. The, and the focus up to now has hence been on the technical system; more understanding has been created and more knowledge has been developed. For future long duration human missions to which we are looking ahead when planning for outposts on the Moon and Mars, the human system has to play an equal role. The environment for which space architects are planning demands an extremely economical use of time, material and resources for the astronauts on mission, as well as attempts a maximum integration of environmental conditions and user requirements in design decisions, but also the mutual influence between humans and their environment, between active and passive systems. Human needs are always the same regardless of whether we are on the planet or in outer space. And they are a very architectural topic. Architecture is the three-dimensional creation of a shelter for humans supporting their needs and expanding their culture. Factors such as habitability (which include but are not limited to colour, smell, surface material tactility, food and the human -- machine interface), socio-psychological factors (which include crew selection and training, heterogeneity versus homogeneity of the crew, coping with stress, group dynamics, cognitive strategies, cultural background of the crew and its implications), culture and thus the resulting proportion of inhabitable space and it's functionality are a few topics of the complex theme 'Human Dimension'.

Habitability in Advanced Space Mission Design. Part 2; Evaluation of Habitation Elements

Science.gov (United States)

Adams, Constance M.; McCurdy, Matthew R.

2000-01-01

Habitability is a fundamental component of any long-duration human habitat. Due to the pressures on the crew and the criticality of their performance, this is particularly true of habitats or vehicles proposed for use in any human space mission of duration over 30 days. This paper, the second of three on this subject, will focus on evaluating all the vehicles currently under consideration for the Mars Design Reference Mission through application of metrics for habitability (proposed in a previous paper, see references Adams/McCurdy 1999).

Habitability: CAMELOT 4

Science.gov (United States)

Alequin, W.; Barragan, A.; Carro, M.; Garcia, F.; Gonzalez, I.; Mercado, J. A.; Negron, N.; Lopez, D.; Rivera, L. A.; Rivera, M.

1990-01-01

During 1988 to 1989 the NASA/USRA Advanced Design Program sponsored research and design efforts aimed at developing habitability criteria and at defining a habitability concept as a useful tool in understanding and evaluating dwellings for prolonged stays in extraterrestrial space. The Circulating Auto sufficient Mars-Earth Luxurious Orbital Transport (CAMELOT) was studied as a case in which the students would try to enhance the quality of life of the inhabitants by applying architectural design methodology. The study proposed 14 habitability criteria considered necessary to fulfill the defined habitability concept, which is that state of equilibrium that results from the interaction between components of the Individual Architecture Mission Complex, which allows a person to sustain physiological homeostatis, adequate performance, and acceptable social relationships. Architecture, design development, refinements and revisions to improve the quality of life, new insights on artificial gravity, form and constitution problems, and the final design concept are covered.

A Method for Choosing the Best Samples for Mars Sample Return.

Science.gov (United States)

Gordon, Peter R; Sephton, Mark A

2018-05-01

Success of a future Mars Sample Return mission will depend on the correct choice of samples. Pyrolysis-FTIR can be employed as a triage instrument for Mars Sample Return. The technique can thermally dissociate minerals and organic matter for detection. Identification of certain mineral types can determine the habitability of the depositional environment, past or present, while detection of organic matter may suggest past or present habitation. In Mars' history, the Theiikian era represents an attractive target for life search missions and the acquisition of samples. The acidic and increasingly dry Theiikian may have been habitable and followed a lengthy neutral and wet period in Mars' history during which life could have originated and proliferated to achieve relatively abundant levels of biomass with a wide distribution. Moreover, the sulfate minerals produced in the Theiikian are also known to be good preservers of organic matter. We have used pyrolysis-FTIR and samples from a Mars analog ferrous acid stream with a thriving ecosystem to test the triage concept. Pyrolysis-FTIR identified those samples with the greatest probability of habitability and habitation. A three-tier scoring system was developed based on the detection of (i) organic signals, (ii) carbon dioxide and water, and (iii) sulfur dioxide. The presence of each component was given a score of A, B, or C depending on whether the substance had been detected, tentatively detected, or not detected, respectively. Single-step (for greatest possible sensitivity) or multistep (for more diagnostic data) pyrolysis-FTIR methods informed the assignments. The system allowed the highest-priority samples to be categorized as AAA (or A*AA if the organic signal was complex), while the lowest-priority samples could be categorized as CCC. Our methods provide a mechanism with which to rank samples and identify those that should take the highest priority for return to Earth during a Mars Sample Return mission. Key Words

Life On Mars: Past, Present and Future

Science.gov (United States)

McKay, Christopher P.; DeVincenzi, Donald L. (Technical Monitor)

2000-01-01

Mars appears to be cold dry and dead world. However there is good evidence that early in its history it had liquid water, more active volcanism, and a thicker atmosphere. Mars had this earth-like environment over three and a half billion years ago, during the same time that life appeared on Earth. The main question in the exploration of Mars then is the search for a independent origin of life on that planet. Ecosystems in cold, dry locations on Earth - such as the Antarctic - provide examples of how life on Mars might have survived and where to look for fossils. Although the Viking results may indicate that Mars has no life today, there is direct geomorphological evidence that, in the past, Mars had large amounts of liquid water on its surface - possibly due to a thicker atmosphere. From a biological perspective the existence of liquid water, by itself motivates the question of the origin of life on Mars. One of the martian meteorites dates back to this early period and may contain evidence consistent with life. From studies of the Earth's earliest biosphere we know that by 3.5 Cyr. ago, life had originated on Earth and reached a fair degree of biological sophistication. Surface activity and erosion on Earth make it difficult to trace the history of life before the 3.5 Cyr timeframe. Ecosystems in cold, dry locations on Earth - such as the Antarctic - provide examples of how life on Mars might have survived and where to look for fossils. Human exploration of Mars will probably begin with a small base manned by a temporary crew, a necessary first start. But exploration of the entire planet will require a continued presence on the Martian surface and the development of a self sustaining community in which humans can live and work for very long periods of time. A permanent Mars research base can be compared to the permanent research bases which several nations maintain in Antarctica at the South Pole, the geomagnetic pole, and elsewhere. In the long run, a continued

Habitability Assessment of International Space Station

Science.gov (United States)

Thaxton, Sherry

2015-01-01

The purpose of this study is to assess habitability during the International Space Station 1-year mission, and subsequent 6-month missions, in order to better prepare for future long-duration spaceflights to destinations such as Near Earth Asteroid (NEA) and Mars, which will require crewmembers to live and work in a confined spacecraft environment for over a year. Data collected using Space Habitability Observation Reporting Tool (iSHORT), crew-collected videos, questionnaires, and PI conferences will help characterize the current state of habitability for the ISS. These naturalistic techniques provide crewmembers with the opportunity to self-report habitability and human factors observations in near real-time, which is not systematically done during ISS missions at present.

SAM : an experiment dedicated to the Carbon Quest at Mars

Science.gov (United States)

Coll, Patrice; Mahaffy, Paul; Webster, Chris; Cabane, Michel; Tan, F.; Coscia, D.; Nolan, T.; Rahen, E.; Teinturier, S.; Goutail, J. P.; Martin, D.; Montaron, C.; Galic, A.

SAM is a suite of instruments that will be onboard the Mars Science Laboratory (MSL) rover. The SAM team consist of scientists and engineers at GSFC, U. Paris/CNRS, JPL, and Honeybee Robotics, along with many additional external partners. SAM's five science goals will address three of the most fundamental questions about the ability of Mars to support life -past, present, and future. Question 1: What does the inventory of carbon compounds near the surface of Mars tell us about its potential habitability? 1.Goal 1: Survey carbon compound sources and evaluate their possible mechanism of formation and destruction. 2.Goal 2: Search for organic compounds of biotic and prebiotic importance expecially methane. Question 2: What are the chemical and isotopic states of the lighter elements in the solids and atmosphere of Mars and what do they tell us about its potential habitability? 1.Goal 3: Reveal the chemical and isotopic state of elements (i.e., N, H, O, S and others) that are important for life as we know it. 2.Goal 4: Evaluate the habitability of Mars by studying its atmospheric chemistry and the composition of trace species that are evidence of interactions between the atmosphere and soil. Question 3: Were past habitability conditions different from today's? 1.Goal 5: Understand atmospheric and climatic evolution through measurements of noble gas and light element isotopes.

Organic molecules in the Sheepbed Mudstone, Gale Crater, Mars

NARCIS (Netherlands)

Freissinet, C.; Glavin, D. P.; Mahaffy, P. R.; Miller, K. E.; Eigenbrode, J. L.; Summons, R. E.; Brunner, A. E.; Buch, A.; Szopa, C.; Archer, P. D.; Franz, H. B.; Atreya, S. K.; Brinckerhoff, W. B.; Cabane, M.; Coll, P.; Conrad, P. G.; Des Marais, D. J.; Dworkin, J. P.; Fairén, A. G.; François, P.; Grotzinger, J. P.; Kashyap, S.; ten Kate, I. L.; Leshin, L. A.; Malespin, C. A.; Martin, M. G.; Martin-Torres, F. J.; Mcadam, A. C.; Ming, D. W.; Navarro-González, R.; Pavlov, A. A.; Prats, B. D.; Squyres, S. W.; Steele, A.; Stern, J. C.; Sumner, D. Y.; Sutter, B.; Zorzano, M. P.

The Sample Analysis at Mars (SAM) instrument on board the Mars Science Laboratory Curiosity rover is designed to conduct inorganic and organic chemical analyses of the atmosphere and the surface regolith and rocks to help evaluate the past and present habitability potential of Mars at Gale Crater.

The Present Habitability Potential of Gale Crater: What We Have Learned So Far From Mars Science Laboratory

Science.gov (United States)

Conrad, P. G.; Archer, P. D.; Domagal-Goldman, S.; Eigenbrode, J.; Fisk, M.; Gupta, S.; Hamilton, V.; Kah, L.; Kahanpaa, Henrik; Martin-Torres, J.;

Habitable periglacial landscapes in martian mid-latitudes

Science.gov (United States)

Ulrich, M.; Wagner, D.; Hauber, E.; de Vera, J.-P.; Schirrmeister, L.

2012-05-01

Subsurface permafrost environments on Mars are considered to be zones where extant life could have survived. For the identification of possible habitats it is important to understand periglacial landscape evolution and related subsurface and environmental conditions. Many landforms that are interpreted to be related to ground ice are located in the martian mid-latitudinal belts. This paper summarizes the insights gained from studies of terrestrial analogs to permafrost landforms on Mars. The potential habitability of martian mid-latitude periglacial landscapes is exemplarily deduced for one such landscape, that of Utopia Planitia, by a review and discussion of environmental conditions influencing periglacial landscape evolution. Based on recent calculations of the astronomical forcing of climate changes, specific climate periods are identified within the last 10 Ma when thaw processes and liquid water were probably important for the development of permafrost geomorphology. No periods could be identified within the last 4 Ma which met the suggested threshold criteria for liquid water and habitable conditions. Implications of past and present environmental conditions such as temperature variations, ground-ice conditions, and liquid water activity are discussed with respect to the potential survival of highly-specialized microorganisms known from terrestrial permafrost. We conclude that possible habitable subsurface niches might have been developed in close relation to specific permafrost landform morphology on Mars. These would have probably been dominated by lithoautotrophic microorganisms (i.e. methanogenic archaea).

Venus: The First Habitable World of Our Solar System?

Science.gov (United States)

Way, Michael Joseph; Del Genio, Anthony; Kiang, Nancy; Sohl, Linda; Clune, Tom; Aleinov, Igor; Kelley, Maxwell

2015-01-01

A great deal of effort in the search for life off-Earth in the past 20+ years has focused on Mars via a plethora of space and ground based missions. While there is good evidence that surface liquid water existed on Mars in substantial quantities, it is not clear how long such water existed. Most studies point to this water existing billions of years ago. However,those familiar with the Faint Young Sun hypothesis for Earth will quickly realize that this problem is even more pronounced for Mars. In this context recent simulations have been completed with the GISS 3-D GCM (1) of paleo Venus (approx. 3 billion years ago) when the sun was approx. 25 less luminous than today. A combination of a less luminous Sun and a slow rotation rate reveal that Venus could have had conditions on its surface amenable to surface liquid water. Previous work has also provided bounds on how much water Venus could have had using measured DH ratios. It is possible that less assumptions have to be made to make Venus an early habitable world than have to be made for Mars, even thoughVenus is a much tougher world on which to confirm this hypothesis.

The Lost City Hydrothermal Field: A Spectroscopic and Astrobiological Analogue for Nili Fossae, Mars.

Science.gov (United States)

Amador, Elena S; Bandfield, Joshua L; Brazelton, William J; Kelley, Deborah

2017-11-01

Low-temperature serpentinization is a critical process with respect to Earth's habitability and the Solar System. Exothermic serpentinization reactions commonly produce hydrogen as a direct by-product and typically produce short-chained organic compounds indirectly. Here, we present the spectral and mineralogical variability in rocks from the serpentine-driven Lost City Hydrothermal Field on Earth and the olivine-rich region of Nili Fossae on Mars. Near- and thermal-infrared spectral measurements were made from a suite of Lost City rocks at wavelengths similar to those for instruments collecting measurements of the martian surface. Results from Lost City show a spectrally distinguishable suite of Mg-rich serpentine, Ca carbonates, talc, and amphibole minerals. Aggregated detections of low-grade metamorphic minerals in rocks from Nili Fossae were mapped and yielded a previously undetected serpentine exposure in the region. Direct comparison of the two spectral suites indicates similar mineralogy at both Lost City and in the Noachian (4-3.7 Ga) bedrock of Nili Fossae, Mars. Based on mapping of these spectral phases, the implied mineralogical suite appears to be extensive across the region. These results suggest that serpentinization was once an active process, indicating that water and energy sources were available, as well as a means for prebiotic chemistry during a time period when life was first emerging on Earth. Although the mineralogical assemblages identified on Mars are unlikely to be directly analogous to rocks that underlie the Lost City Hydrothermal Field, related geochemical processes (and associated sources of biologically accessible energy) were once present in the subsurface, making Nili Fossae a compelling candidate for a once-habitable environment on Mars. Key Words: Mars-Habitability-Serpentinization-Analogue. Astrobiology 17, 1138-1160.

How Do Modern Extreme Hydrothermal Environments Inform the Identification of Martian Habitability? The Case of the El Tatio Geyser Field

Directory of Open Access Journals (Sweden)

Roberto Barbieri

2014-11-01

Full Text Available Despite the success in knowledge gained by the Mars missions in the last two decades, the search for traces of life on Mars is still in progress. The reconstruction of (paleo- environments on Mars have seen a dramatic increase, in particular with regard to the potentially habitable conditions, and it is now possible to recognize a significant role to subaerial hydrothermal processes. For this reason, and because the conditions of the primordial Earth—when these extreme environments had to be common—probably resembled Mars during its most suitable time to host life, research on terrestrial extreme hydrothermal habitats may assist in understanding how to recognize life on Mars. A number of geological and environmental reasons, and logistics opportunities, make the geothermal field of El Tatio, in the Chilean Andes an ideal location to study.

A Methane-Rich Early Mars: Implications for Habitability and the Emergence of Life

Science.gov (United States)

Wong, Michael L.; Friedson, Andrew James; Willacy, Karen; Shia, Run-Lie; Yung, Yuk; Russell, Michael J.

2017-10-01

We investigate the radiation and chemistry of a ~4.0 Ga, CH4-rich martian atmosphere in an effort to assess whether or not Mars was once habitable and suitable for the emergence of life. High atmospheric CH4 may be consistent with a mantle that does not reach the requisite pressure (24 GPa) and temperature (1900 K) for the silicate spinel-to-perovskite transition (Dale et al., 2012; McCammon, 1997; Wadhwa, 2001; Wood et al., 2006). Impact degassing from chondritic material can also contribute substantial amounts of CH4 to the atmosphere (Schaefer and Fegley, 2007). CH4 plays an important role in atmospheric radiation. Atmospheric models have demonstrated that a purely CO2 atmosphere, even one as massive as 7 bars, is incapable of heating Mars above an annual-mean surface temperature of 273 K (Forget et al., 2013), although recent studies show that recurring wet states could have been induced in an H2-rich atmosphere (Batalha et al., 2015, 2016). We show that CH4 alone is insufficient to warm early Mars above freezing—in fact it produces an anti-greenhouse effect—but it substantially raises middle atmospheric temperatures. We determine whether or not such high temperatures could prolong the photochemical lifetime of SO2, another potent greenhouse gas. We use RC1D, a non-gray 1-D radiative-convective equilibrium model, to calculate the atmospheric thermal structure consistent with the radiative heating and cooling associated with the composition computed at each chemical model time step. KINETICS, the Caltech/JPL chemistry transport model (e.g. Nair et al., 1994), determines the chemical makeup of the atmosphere, evaluating steady-state chemical profiles and the synthesis of astrobiologically relevant molecules. H2O is in vapor pressure equilibrium at the surface. We consider conditions forced by the faint-young Sun’s spectrum and luminosity. By coupling RC1D and KINETICS, we are able to paint a more realistic picture of Mars’s early climate, calculating the

Is Mars a habitable environment for extremophilic microorganisms from Earth?

Science.gov (United States)

Rettberg, Petra; Reitz, Guenther; Flemming, Hans-Curt; Bauermeister, Anja

In the last decades several sucessful space missions to our neighboring planet Mars have deepened our knowledge about its environmental conditions substantially. Orbiters with intruments for remote sensing and landers with sophisticated intruments for in situ investigations resulted in a better understanding of Mars’ radiation climate, atmospheric composition, geology, and mineralogy. Extensive regions of the surface of Mars are covered with sulfate- and ferric oxide-rich layered deposits. These sediments indicate the possible existence of aqueous, acidic environments on early Mars. Similar environments on Earth harbour a specialised community of microorganisms which are adapted to the local stress factors, e.g. low pH, high concentrations of heavy metal ions, oligotrophic conditions. Acidophilic iron-sulfur bacteria isolated from such habitats on Earth could be considered as model organisms for an important part of a potential extinct Martian ecosystem or an ecosystem which might even exist today in protected subsurface niches. Acidithiobacillus ferrooxidans was chosen as a model organism to study the ability of these bacteria to survive or grow under conditions resembling those on Mars. Stress conditions tested included desiccation, radiation, low temperatures, and high salinity. It was found that resistance to desiccation strongly depends on the mode of drying. Biofilms grown on membrane filters can tolerate longer periods of desiccation than planktonic cells dried without any added protectants, and drying under anaerobic conditions is more favourable to survival than drying in the presence of oxygen. Organic compounds such as trehalose and glycine betaine had a positive influence on survival after drying and freezing. A. ferrooxidans was shown to be sensitive to high salt concentrations, ionizing radiation, and UV radiation. However, the bacteria were able to utilize the iron minerals in Mars regolith mixtures as sole energy source. The survival and growth of

Modeling soluble salt assemblages on Mars: past aqueous history and present-day habitability

Science.gov (United States)

Toner, J. D.; Catling, D. C.; Light, B.

2014-12-01

Soluble salt assemblages formed through aqueous processes are widespread on Mars. These minerals are important for understanding the past aqueous history of Mars and indicate critical habitability parameters such as pH, temperature, water activity, and salinity. Equilibrium models have been used to determine solution chemistry and salt precipitation sequences from aqueous chemical data; however, current models are limited by a lack of experimental data for low-temperature perchlorates, and some model predictions are clearly anomalous. To address the need for accurate equilibrium models, we have developed a comprehensive model for low-temperature perchlorate-rich brines using (1) previously neglected literature data, (2) experimental solubilities determined in low-temperature perchlorate solutions, and (3) solubility and heat capacity results determined using Differential Scanning Calorimetry (DSC). Our resulting model is a significant improvement over existing models, such as FREZCHEM, particularly for perchlorate mixtures. We have applied our model to evaporation and freezing of a nominal Wet Chemistry Laboratory (WCL) solution measured at the Phoenix site. For a freezing WCL solution, our model indicates that ice, KClO4, hydromagnesite (3MgCO3·Mg(OH)2·3H2O), calcite (CaCO3), meridianiite (MgSO4·11H2O), MgCl2·12H2O, NaClO4·2H2O, and Mg(ClO4)2·6H2O form at the eutectic (209 K); whereas, KClO4, hydromagnesite, kieserite (MgSO4·H2O), anhydrite (CaSO4), halite (NaCl), NaClO4·H2O, and Mg(ClO4)2·6H2O form upon complete evaporation at 298 K. In general, evaporation yields more dehydrated mineral assemblages than salts produced by freezing. Hydrated phases that form during evaporation contain 0.3 wt. % water, which compares with 1.2 wt. % during freezing. Given independent evidence for the presence of calcite and minimum water contents in Martian soils of ~1.5 wt. %, salts at the Phoenix site, and possibly elsewhere, appear more likely to have formed during

Science Driven Human Exploration of Mars

Science.gov (United States)

McKay, Christopher P.

2004-01-01

Mars appears to be cold dry and dead world. However there is good evidence that early in its history it had liquid water, more active volcanism, and a thicker atmosphere. Mars had this earth-like environment over three and a half billion years ago, during the same time that life appeared on Earth. The main question in the exploration of Mars then is the search for a independent origin of life on that planet. Ecosystems in cold, dry locations on Earth - such as the Antarctic - provide examples of how life on Mars might have survived and where to look for fossils. Fossils are not enough. We will want to determine if life on Mars was a separate genesis from life on Earth. For this determination we need to access intact martian life; possibly frozen in the deep old permafrost. Human exploration of Mars will probably begin with a small base manned by a temporary crew, a necessary first start. But exploration of the entire planet will require a continued presence on the Martian surface and the development of a self sustaining community in which humans can live and work for very long periods of time. A permanent Mars research base can be compared to the permanent research bases which several nations maintain in Antarctica at the South Pole, the geomagnetic pole, and elsewhere. In the long run, a continued human presence on Mars will be the most economical way to study that planet in detail. It is possible that at some time in the future we might recreate a habitable climate on Mars, returning it to the life-bearing state it may have enjoyed early in its history. Our studies of Mars are still in a preliminary state but everything we have learned suggests that it may be possible to restore Mars to a habitable climate. Additional information is contained in the original extended abstract.

The Search for Habitable Environments in the Solar System

Science.gov (United States)

McCleese, Daniel

2005-07-01

All space faring nations devote a portion of their resources to exploring thesolar system. NASA has a forty-year history of robotic missions reaching into deep spacefor a better understanding of our origins, the evolution of our planet, and our destiny.For the past decade, NASA has placed considerable emphasis on the search for life beyondEarth. Missions to the rocky terrestrial planets and the moons of the gas giants seekanswers to the question: Are other worlds in the solar system habitable by simpleorganisms? By framing its search objective in this way, NASA motivates investigations ofthe fundamentals of what makes a planet an abode for life, and what ingredients arerequired for the origin and evolution of life. In this lecture, we focus on thestrategies and results of the search thus far. We will discuss recent scientific missionsto Mars, Europa, and Titan.Dr. Dan McCleese is the Chief Scientist for NASA's Mars ExplorationProgram at JPL. In this role he has worked with NASA and the international sciencecommunity to establish the current science strategy for exploring Mars. Dan's personalscience interests are focused on acquiring and interpreting climatological data sets forthe terrestrial planets. Specific research topics include development of the firstclimatology of cloud height for Earth, upper atmospheric cloud and thermal structure ofVenus, and, at present, the modern climate of Mars. He is the Principal Investigator forthe Mars Climate Sounder on the Mars Reconnaissance Orbiter to be launched in 2005. Inthis investigation, measurements of atmospheric water vapor, temperature and condensates,and the energy balance of the polar caps are emphasized. Dr. McCleese was a FulbrightScholar at Oxford University receiving a D.Phil. degree in Atmospheric Physics.

Shallow transient liquid water environments on present-day mars, and their implications for life

Science.gov (United States)

Jones, Eriita G.

2018-05-01

The identification and characterisation of subsurface liquid water environments on Mars are of high scientific interest. Such environments have the potential to support microbial life, and, more broadly, to develop our understanding of the habitability of planets and moons beyond Earth. Given our current state of knowledge of life on Earth, three pre-requisites are necessary for an environment to be considered 'habitable' and therefore capable of supporting terrestrial-like life: energy, biogenic elements, and liquid water with a sufficiently high water activity. The surface of Mars today is predominately cold and dry, and any liquid water exposed to the atmosphere will vaporise or freeze on timescales of hours to days. These conditions have likely persisted for much of the last 10 million years, and perhaps longer. Despite this, briny liquid water flows (Recurrent Slope Linea) have been observed in a number of locations in the present-day. This review examines evidence from the Phoenix Lander (2008) and the Mars Science Laboratory (2012-current), to assess the occurrence of habitable conditions in the shallow Martian regolith. It will be argued that shallow, transient, liquid water brines are potentially habitable by microbial life, are likely a widespread occurrence on Mars, and that future exploration aimed at finding present-day habitable conditions and potential biology should 'follow the salt'.

An origin of life on Mars.

Science.gov (United States)

McKay, Christopher P

2010-04-01

Evidence of past liquid water on the surface of Mars suggests that this world once had habitable conditions and leads to the question of life. If there was life on Mars, it would be interesting to determine if it represented a separate origin from life on Earth. To determine the biochemistry and genetics of life on Mars requires that we have access to an organism or the biological remains of one-possibly preserved in ancient permafrost. A way to determine if organic material found on Mars represents the remains of an alien biological system could be based on the observation that biological systems select certain organic molecules over others that are chemically similar (e.g., chirality in amino acids).

Human Research Program: Space Human Factors and Habitability Element

Science.gov (United States)

Russo, Dane M.

2007-01-01

The three project areas of the Space Human Factors and Habitability Element work together to achieve a working and living environment that will keep crews healthy, safe, and productive throughout all missions -- from Earth orbit to Mars expeditions. The Advanced Environmental Health (AEH) Project develops and evaluates advanced habitability systems and establishes requirements and health standards for exploration missions. The Space Human Factors Engineering (SHFE) Project s goal is to ensure a safe and productive environment for humans in space. With missions using new technologies at an ever-increasing rate, it is imperative that these advances enhance crew performance without increasing stress or risk. The ultimate goal of Advanced Food Technology (AFT) Project is to develop and deliver technologies for human centered spacecraft that will support crews on missions to the moon, Mars, and beyond.

The Mawrth Vallis region of Mars: A potential landing site for the Mars Science Laboratory (MSL) mission.

Science.gov (United States)

Michalski, Joseph R; Jean-PierreBibring; Poulet, François; Loizeau, Damien; Mangold, Nicolas; Dobrea, Eldar Noe; Bishop, Janice L; Wray, James J; McKeown, Nancy K; Parente, Mario; Hauber, Ernst; Altieri, Francesca; Carrozzo, F Giacomo; Niles, Paul B

2010-09-01

The primary objective of NASA's Mars Science Laboratory (MSL) mission, which will launch in 2011, is to characterize the habitability of a site on Mars through detailed analyses of the composition and geological context of surface materials. Within the framework of established mission goals, we have evaluated the value of a possible landing site in the Mawrth Vallis region of Mars that is targeted directly on some of the most geologically and astrobiologically enticing materials in the Solar System. The area around Mawrth Vallis contains a vast (>1 × 10⁶ km²) deposit of phyllosilicate-rich, ancient, layered rocks. A thick (>150 m) stratigraphic section that exhibits spectral evidence for nontronite, montmorillonite, amorphous silica, kaolinite, saponite, other smectite clay minerals, ferrous mica, and sulfate minerals indicates a rich geological history that may have included multiple aqueous environments. Because phyllosilicates are strong indicators of ancient aqueous activity, and the preservation potential of biosignatures within sedimentary clay deposits is high, martian phyllosilicate deposits are desirable astrobiological targets. The proposed MSL landing site at Mawrth Vallis is located directly on the largest and most phyllosilicate-rich deposit on Mars and is therefore an excellent place to explore for evidence of life or habitability.

Combining meteorites and missions to explore Mars.

Science.gov (United States)

McCoy, Timothy J; Corrigan, Catherine M; Herd, Christopher D K

2011-11-29

Laboratory studies of meteorites and robotic exploration of Mars reveal scant atmosphere, no evidence of plate tectonics, past evidence for abundant water, and a protracted igneous evolution. Despite indirect hints, direct evidence of a martian origin came with the discovery of trapped atmospheric gases in one meteorite. Since then, the study of martian meteorites and findings from missions have been linked. Although the meteorite source locations are unknown, impact ejection modeling and spectral mapping of Mars suggest derivation from small craters in terrains of Amazonian to Hesperian age. Whereas most martian meteorites are young ( 4.5 Ga and formation of enriched and depleted reservoirs. However, the history inferred from martian meteorites conflicts with results from recent Mars missions, calling into doubt whether the igneous histor y inferred from the meteorites is applicable to Mars as a whole. Allan Hills 84001 dates to 4.09 Ga and contains fluid-deposited carbonates. Accompanying debate about the mechanism and temperature of origin of the carbonates came several features suggestive of past microbial life in the carbonates. Although highly disputed, the suggestion spurred interest in habitable extreme environments on Earth and throughout the Solar System. A flotilla of subsequent spacecraft has redefined Mars from a volcanic planet to a hydrologically active planet that may have harbored life. Understanding the history and habitability of Mars depends on understanding the coupling of the atmosphere, surface, and subsurface. Sample return that brings back direct evidence from these diverse reservoirs is essential.

Mass Spectrometry on Future Mars Landers

Science.gov (United States)

Brinckerhoff, W. B.; Mahaffy, P. R.

2011-01-01

Mass spectrometry investigations on the 2011 Mars Science Laboratory (MSL) and the 2018 ExoMars missions will address core science objectives related to the potential habitability of their landing site environments and more generally the near-surface organic inventory of Mars. The analysis of complex solid samples by mass spectrometry is a well-known approach that can provide a broad and sensitive survey of organic and inorganic compounds as well as supportive data for mineralogical analysis. The science value of such compositional information is maximized when one appreciates the particular opportunities and limitations of in situ analysis with resource-constrained instrumentation in the context of a complete science payload and applied to materials found in a particular environment. The Sample Analysis at Mars (SAM) investigation on MSL and the Mars Organic Molecule Analyzer (MOMA) investigation on ExoMars will thus benefit from and inform broad-based analog field site work linked to the Mars environments where such analysis will occur.

Mars Surface Environmental Issues

Science.gov (United States)

Charles, John

2002-01-01

Planetary exploration by astronauts will require extended periods of habitation on a planet's surface, under the influence of environmental factors that are different from those of Earth and the spacecraft that delivered the crew to the planet. Human exploration of Mars, a possible near-term planetary objective, can be considered a challenging scenario. Mission scenarios currently under consideration call for surface habitation periods of from 1 to 18 months on even the earliest expeditions. Methods: Environmental issues associated with Mars exploration have been investigated by NASA and the National Space Biomedical Research Institute (NSBRI) as part of the Bioastronautics Critical Path Roadmap Project (see http ://criticalpath.jsc.nasa.gov). Results: Arrival on Mars will immediately expose the crew to gravity only 38% of that at Earth's surface in possibly the first prolonged exposure to gravity other than the 1G of Earth's surface and the zero G of weightless space flight, with yet unknown effects on crew physiology. The radiation at Mars' surface is not well documented, although the planet's bulk and even its thin atmosphere may moderate the influx of galactic cosmic radiation and energetic protons from solar flares. Secondary radiation from activated components of the soil must also be considered. Ultrafine and larger respirable and nonrespirable particles in Martian dust introduced into the habitat after surface excursions may induce pulmonary inflammation exacerbated by the additive reactive and oxidizing nature of the dust. Stringent decontamination cannot eliminate mechanical and corrosive effects of the dust on pressure suits and exposed machinery. The biohazard potential of putative indigenous Martian microorganisms may be assessed by comparison with analog environments on Earth. Even in their absence, human microorganisms, if not properly controlled, can be a threat to the crew's health. Conclusions: Mars' surface offers a substantial challenge to the

An Origin of Life on Mars

Science.gov (United States)

McKay, Christopher P.

2010-01-01

Evidence of past liquid water on the surface of Mars suggests that this world once had habitable conditions and leads to the question of life. If there was life on Mars, it would be interesting to determine if it represented a separate origin from life on Earth. To determine the biochemistry and genetics of life on Mars requires that we have access to an organism or the biological remains of one—possibly preserved in ancient permafrost. A way to determine if organic material found on Mars represents the remains of an alien biological system could be based on the observation that biological systems select certain organic molecules over others that are chemically similar (e.g., chirality in amino acids). PMID:20452949

Curiosity: the Mars Science Laboratory Project

Science.gov (United States)

Cook, Richard A.

2012-01-01

The Curiosity rover landed successfully in Gale Crater, Mars on August 5, 2012. This event was a dramatic high point in the decade long effort to design, build, test and fly the most sophisticated scientific vehicle ever sent to Mars. The real achievements of the mission have only just begun, however, as Curiosity is now searching for signs that Mars once possessed habitable environments. The Mars Science Laboratory Project has been one of the most ambitious and challenging planetary projects that NASA has undertaken. It started in the successful aftermath of the 2003 Mars Exploration Rover project and was designed to take significant steps forward in both engineering and scientific capabilities. This included a new landing system capable of emplacing a large mobile vehicle over a wide range of potential landing sites, advanced sample acquisition and handling capabilities that can retrieve samples from both rocks and soil, and a high reliability avionics suite that is designed to permit long duration surface operations. It also includes a set of ten sophisticated scientific instruments that will investigate both the geological context of the landing site plus analyze samples to understand the chemical & organic composition of rocks & soil found there. The Gale Crater site has been specifically selected as a promising location where ancient habitable environments may have existed and for which evidence may be preserved. Curiosity will spend a minimum of one Mars year (about two Earth years) looking for this evidence. This paper will report on the progress of the mission over the first few months of surface operations, plus look retrospectively at lessons learned during both the development and cruise operations phase of the mission..

Applications of Surface Penetrating Radar for Mars Exploration

Science.gov (United States)

Li, H.; Li, C.; Ran, S.; Feng, J.; Zuo, W.

2015-12-01

Surface Penetrating Radar (SPR) is a geophysical method that uses electromagnetic field probe the interior structure and lithological variations of a lossy dielectric materials, it performs quite well in dry, icy and shallow-soil environments. The first radar sounding of the subsurface of planet was carried out by Apollo Lunar Sounder Experiment (ALSE) of the Apollo 17 in 1972. ALSE provided very precise information about the moon's topography and revealed structures beneath the surface in both Mare Crisium and Mare Serenitatis. Russian Mars'92 was the first Mars exploration mission that tried to use SPR to explore martian surface, subsurface and ionosphere. Although Mars'96 launch failed in 1996, Russia(Mars'98, cancelled in 1998; Phobos-Grunt, launch failed in 2011), ESA(Mars Express, succeeded in 2003; Netlander, cancelled in 2003; ExoMars 2018) and NASA(MRO, succeeded in 2005; MARS 2020) have been making great effects to send SPR to Mars, trying to search for the existence of groundwater and life in the past 20 years. So far, no Ground Penetrating Radar(GPR) has yet provided in situ observations on the surface of Mars. In December 2013, China's CE-3 lunar rover (Yuto) equipped with a GPR made the first direct measurement of the structure and depth of the lunar soil, and investigation of the lunar crust structure along the rover path. China's Mars Exploration Program also plans to carry the orbiting radar sounder and rover GPR to characterize the nature of subsurface water or ices and the layered structure of shallow subsurface of Mars. SPR can provide diversity of applications for Mars exploration , that are: to map the distribution of solid and liquid water in the upper portions of the Mars' crust; to characterize the subsurface geologic environment; to investigate the planet's subsurface to better understand the evolution and habitability of Mars; to perform the martain ionosphere sounding. Based on SPR's history and achievements, combined with the

Mars: Periglacial Morphology and Implications for Future Landing Sites

Science.gov (United States)

Heldmann, Jennifer L.; Schurmeier, Lauren; McKay, Christopher; Davila, Alfonso; Stoker, Carol; Marinova, Margarita; Wilhelm, Mary Beth

2015-01-01

At the Mars Phoenix landing site and in much of the Martian northern plains, there is ice-cemented ground beneath a layer of dry permafrost. Unlike most permafrost on Earth, though, this ice is not liquid at any time of year. However, in past epochs at higher obliquity the surface conditions during summer may have resulted in warmer conditions and possible melting. This situation indicates that the ice-cemented ground in the north polar plains is likely to be a candidate for the most recently habitable place on Mars as near-surface ice likely provided adequate water activity approximately 5 Myr ago. The high elevation Dry Valleys of Antarctica provide the best analog on Earth of Martian ground ice. These locations are the only places on Earth where ice-cemented ground is found beneath dry permafrost. The Dry Valleys are a hyper-arid polar desert environment and in locations above 1500 m elevation, such as University Valley, air temperatures do not exceed 0 C. Thus, similarly to Mars, liquid water is largely absent here and instead the hydrologic cycle is dominated by frozen ice and vapor phase processes such as sublimation. These conditions make the high elevation Dry Valleys a key Mars analog location where periglacial processes and geomorphic features can be studied in situ. This talk will focus on studies of University Valley as a Mars analog for periglacial morphology and ice stability. We will review a landing site selection study encompassing this information gleaned from the Antarctic terrestrial analog studies plus Mars spacecraft data analysis to identify candidate landing sites for a future mission to search for life on Mars.

Habit versus choice: the process of decision-making in health-related behaviour.

Science.gov (United States)

Lindbladh, Eva; Lyttkens, Carl Hampus

2002-08-01

Social differences in the role of habits in health-related behaviour are explored within both sociology and economics, where we define habits as non-reflective, repetitive behaviour. The corresponding theoretical perspectives are the habitus theory, the theory of individualization, and habits as rational decision rules. Sixteen thematically structured interviews are analysed using qualitative methodology. Three aspects of habits emerged from the narrative: the association between habits and preferences, habits as a source of utility, and the relationship between habits and norms. We find that people in lower social positions are more inclined to rely on their habits and are accordingly less likely to change their behaviour. These differences are reinforced as not only the disposition to maintain habits but also the tendency to conceive of the habitual as something good seems to be strengthened in lower social positions. We also note that the intensified individualization that characterizes current society erodes the basis for habit-governed behaviour, which may also contribute to social differences in well-being. Finally, we find that the scientific dialogue has enriched both scientific paradigms, and suggest as a tentative hypothesis that the traditional economic rational-actor model may be relatively less applicable to those with limited resources.

Is Mars Dead and Does it Matter: The Crucial Scientific Importance of a Lifeless Mars

Science.gov (United States)

Fries, M.; Conrad, P. G.; Steele, A.

2017-12-01

The quest for signatures of ancient and/or present-day life on Mars is an important driving force in modern Mars science and exploration. The reasons for this have been spelled out in detail elsewhere, such as in the 2013-2022 Planetary Science decadal survey. We do not question the importance of the search for life, but would like to expound on the inverse case. Namely, if Mars is lifeless then it is one of the most astrobiologically important locales in the Solar System and is worthy of detailed and thorough investigation as such. At present we are aware of only one place in the universe that hosts biology, the Earth. Arguably one of the most important aspects of understanding life is the quandary of how life arose, and considerable work has been done on understanding this question. However, progress has been hampered by the fact that the conditions that facilitated the rise of life on Earth are almost completely lost; they have been overprinted by biological activity, altered by our oxygen- and water-rich modern environment, and physically destroyed by crustal recycling. None of these effects are present on a lifeless Mars. Whereas on a "living" Mars any habitable environment would be colonized and altered, a lifeless Mars should retain preserved environments - either planetary-scale or microenvironments - which preserve a record of the original physiochemical conditions suitable for the origin of life on a terrestrial planet. No other world has the same potential to preserve this record; Mercury, the Moon, Phobos and Deimos do not show signs of ever being habitable, Venus has a surface that has been mercilessly thermally altered and is difficult to access, and even the Earth itself has been extensively altered. Ceres is uncertain in this respect as that world is unlikely to ever have hosted a significant atmosphere and its potential status as an early ocean world is still debated. The irony here is that a Mars free of life is a unique and scientifically

The Role of Habitability Studies in Space Facility and Vehicle Design

Science.gov (United States)

Adams, Constance M.

1999-01-01

This document is a viewgraph presentation which reviews the role of the space architect in designing a space vehicle with habitability as a chief concern. Habitability is composed of the qualities of the environment or system which support the crew in working and living. All the impacts from habitability are interdependent; i.e., impacts to well-being can impact performance, safety or efficiency. After reviewing the issues relating to habitability the presentation discusses the application of these issues in two case studies. The first studies the Bio-Plex Hab chamber which includes designs of the living and working areas. The second case study is the ISS-TransHab which is being studied as a prototype for Mars transit.

Habitability of waterworlds: runaway greenhouses, atmospheric expansion, and multiple climate states of pure water atmospheres.

Science.gov (United States)

Goldblatt, Colin

2015-05-01

There are four different stable climate states for pure water atmospheres, as might exist on so-called "waterworlds." I map these as a function of solar constant for planets ranging in size from Mars-sized to 10 Earth-mass. The states are as follows: globally ice covered (Ts ⪅ 245 K), cold and damp (270 ⪅ Ts ⪅ 290 K), hot and moist (350 ⪅ Ts ⪅ 550 K), and very hot and dry (Tsx2A86;900 K). No stable climate exists for 290 ⪅ T s ⪅ 350 K or 550 ⪅ Ts ⪅ 900 K. The union of hot moist and cold damp climates describes the liquid water habitable zone, the width and location of which depends on planet mass. At each solar constant, two or three different climate states are stable. This is a consequence of strong nonlinearities in both thermal emission and the net absorption of sunlight. Across the range of planet sizes, I account for the atmospheres expanding to high altitudes as they warm. The emitting and absorbing surfaces (optical depth of unity) move to high altitude, making their area larger than the planet surface, so more thermal radiation is emitted and more sunlight absorbed (the former dominates). The atmospheres of small planets expand more due to weaker gravity; the effective runaway greenhouse threshold is about 35 W m(-2) higher for Mars, 10 W m(-2) higher for Earth or Venus, but only a few W m(-2) higher for a 10 Earth-mass planet. There is an underlying (expansion-neglected) trend of increasing runaway greenhouse threshold with planetary size (40 W m(-2) higher for a 10 Earth-mass planet than for Mars). Summing these opposing trends means that Venus-sized (or slightly smaller) planets are most susceptible to a runaway greenhouse. The habitable zone for pure water atmospheres is very narrow, with an insolation range of 0.07 times the solar constant. A wider habitable zone requires background gas and greenhouse gas: N2 and CO2 on Earth, which are biologically controlled. Thus, habitability depends on inhabitance.

The Development of the Chemin Mineralogy Instrument and Its Deployment on Mars (and Latest Results from the Mars Science Laboratory Rover Curiosity)

Science.gov (United States)

Blake, David F.

2014-01-01

The CheMin instrument (short for "Chemistry and Mineralogy") on the Mars Science Laboratory rover Curiosity is one of two "laboratory quality" instruments on board the Curiosity rover that is exploring Gale crater, Mars. CheMin is an X-ray diffractometer that has for the first time returned definitive and fully quantitative mineral identifications of Mars soil and drilled rock. I will describe CheMin's 23-year development from an idea to a spacecraft qualified instrument, and report on some of the discoveries that Curiosity has made since its entry, descent and landing on Aug. 6, 2012, including the discovery and characterization of the first habitable environment on Mars.

Camille Flammarion's the planet Mars as translated by Patrick Moore

CERN Document Server

2015-01-01

Camille Flammarion (1842-1925) began his career at 16 as a human computer under the great mathematician U. J. J. Le Verrier at the Paris Observatory.  He soon tired of the drudgery; he was drawn to more romantic vistas, and at 19 wrote a book on an idea that he was to make his own—the habitability of other worlds.  There followed a career as France’s greatest popularizer of astronomy, with over 60 titles to his credit.  An admirer granted him a chateau at Juvisy-sur-l’Orge, and he set up a first-rate observatory dedicated to the study of the planet Mars. Finally, in 1892, he published his masterpiece, La Planete Mars et ses conditions d’habitabilite, a comprehensive summary of three centuries’ worth of literature on Mars, much of it based on his own personal research into rare memoirs and archives.  As a history of that era, it has never been surpassed, and remains one of a handful of indispensable books on the red planet. Sir Patrick Moore (1923-2012) needs no introduction; his record of popula...

Volatile and Isotopic Imprints of Ancient Mars

Science.gov (United States)

Mahaffy, Paul R.; Conrad, Pamela G.

2015-01-01

The science investigations enabled by Curiosity rover's instruments focus on identifying and exploring the habitability of the Martian environment. Measurements of noble gases, organic and inorganic compounds, and the isotopes of light elements permit the study of the physical and chemical processes that have transformed Mars throughout its history. Samples of the atmosphere, volatiles released from soils, and rocks from the floor of Gale Crater have provided a wealth of new data and a window into conditions on ancient Mars.

Planetary Simulation Chambers bring Mars to laboratory studies

Energy Technology Data Exchange (ETDEWEB)

Mateo-Marti, E.

2016-07-01

Although space missions provide fundamental and unique knowledge for planetary exploration, they are always costly and extremely time-consuming. Due to the obvious technical and economical limitations of in-situ planetary exploration, laboratory simulations are among the most feasible research options for making advances in planetary exploration. Therefore, laboratory simulations of planetary environments are a necessary and complementary option to expensive space missions. Simulation chambers are economical, more versatile, and allow for a higher number of experiments than space missions. Laboratory-based facilities are able to mimic the conditions found in the atmospheres and on the surfaces of a majority of planetary objects. Number of relevant applications in Mars planetary exploration will be described in order to provide an understanding about the potential and flexibility of planetary simulation chambers systems: mainly, stability and presence of certain minerals on Mars surface; and microorganisms potential habitability under planetary environmental conditions would be studied. Therefore, simulation chambers will be a promising tools and necessary platform to design future planetary space mission and to validate in-situ measurements from orbital or rover observations. (Author)

A concept for NASA's Mars 2016 astrobiology field laboratory.

Science.gov (United States)

Beegle, Luther W; Wilson, Michael G; Abilleira, Fernando; Jordan, James F; Wilson, Gregory R

2007-08-01

The Mars Program Plan includes an integrated and coordinated set of future candidate missions and investigations that meet fundamental science objectives of NASA and the Mars Exploration Program (MEP). At the time this paper was written, these possible future missions are planned in a manner consistent with a projected budget profile for the Mars Program in the next decade (2007-2016). As with all future missions, the funding profile depends on a number of factors that include the exact cost of each mission as well as potential changes to the overall NASA budget. In the current version of the Mars Program Plan, the Astrobiology Field Laboratory (AFL) exists as a candidate project to determine whether there were (or are) habitable zones and life, and how the development of these zones may be related to the overall evolution of the planet. The AFL concept is a surface exploration mission equipped with a major in situ laboratory capable of making significant advancements toward the Mars Program's life-related scientific goals and the overarching Vision for Space Exploration. We have developed several concepts for the AFL that fit within known budget and engineering constraints projected for the 2016 and 2018 Mars mission launch opportunities. The AFL mission architecture proposed here assumes maximum heritage from the 2009 Mars Science Laboratory (MSL). Candidate payload elements for this concept were identified from a set of recommendations put forth by the Astrobiology Field Laboratory Science Steering Group (AFL SSG) in 2004, for the express purpose of identifying overall rover mass and power requirements for such a mission. The conceptual payload includes a Precision Sample Handling and Processing System that would replace and augment the functionality and capabilities provided by the Sample Acquisition Sample Processing and Handling system that is currently part of the 2009 MSL platform.

Developing a High Fidelity Martian Soil Simulant Based on MSL Measurements: Applications for Habitability, Exploration, and In-Situ Resource Utilization

Science.gov (United States)

Cannon, K.; Britt, D. T.; Smith, T. M.; Fritsche, R. F.; Covey, S. D.; Batcheldor, D.; Watson, B.

2017-12-01

applications include studies of habitability, toxicity, and in-situ resource utilization, among others. Through a partnership with Deep Space Industries we intend to produce industrial quantities of Mars Global from consistently maintained feedstocks, making it available to researchers, engineers, and educators.

Assessing Habitability: Lessons from the Phoenix Mission

Science.gov (United States)

Stoker, Carol R.

2013-01-01

various regions visited to date on Mars that involved computing a habitability probability, defined as the product of probabilities for the presence of liquid water (P(sub lw)), energy (P(sub e)), nutrients (P(sub ch)), and a benign environment (P(sub b)). Using this formalism, they argued that the Phoenix site was the most habitable of any site visited to date by landed missions and warranted a follow up mission to search for modern evidence of life. This paper will review that conclusion in view of more recent information from the Mars Exploration Rovers and Mars Science Lander missions.

Nitrogen and Martian Habitability: Insights from Five Years of Curiosity Measurements

Science.gov (United States)

Stern, J. C.; Sutter, B.; Navarro-Gonzalez, R.; McKay, C.; Ming, D. W.; Mahaffy, P. R.; Archer, D., Jr.; Franz, H. B.; Freissinet, C.; Jackson, W. A.; Conrad, P. G.; Glavin, D. P.; Trainer, M. G.; Malespin, C.; McAdam, A.; Eigenbrode, J. L.; Teinturier, S.; Manning, C.

2017-12-01

The detection of "fixed" N on Mars in the form of nitrate by the Sample Analysis at Mars (SAM) instrument suite on the Mars Science Laboratory (MSL) Curiosity Rover [1] has major implications for martian habitability. "Follow the nitrogen" has been proposed as a strategy in the search for both extant and extinct life on Mars [e.g., 2]. Nitrogen is so crucial to life on Earth that life developed metabolic pathways to break the triple bond of N2 and "fix" atmospheric nitrogen to more biologically available molecules for use in proteins and informational polymers. Sequestration of nitrate in regolith has long been predicted to contribute to the removal of N from the martian atmosphere [e.g., 3], and our detections confirm that nitrogen fixation was occurring on ancient Mars. Detections of fixed nitrogen, particularly within the context of the habitable environment in Yellowknife Bay characterized by the MSL payload, are an important tool to assess whether life ever could have existed on ancient Mars. We present 5 years of analyses and interpretation of nitrate in solid martian drilled and scooped samples by SAM on MSL. Nitrate abundance reported by SAM in situ measurements ranges from non-detection to 681 ± 304 mg/kg [1,4] in the samples examined to date. The measured abundances are consistent with nitrogen fixation via impact generated thermal shock on ancient Mars and/or dry deposition from photochemistry of thermospheric NO. We review the integration of SAM data with terrestrial Mars analog work in order to better understand the timing of nitrogen fixation and mobility of nitrogen on Mars, and thus its availability to putative biology. In particular, the relationship between nitrate and other soluble salts, such as perchlorate, may help reveal the timing of nitrogen fixation and post-depositional behavior of nitrate on Mars [4]. Finally, we present a comparison of isotopic composition (δ15N) of nitrate with δ15N of atmospheric nitrogen (δ15N ≈ 574‰, [5

Early Life Crises of Habitable Planets

International Nuclear Information System (INIS)

Pierrehumbert, Raymond

2006-01-01

There are a number of crises that a potentially habitable planet must avoid or surmount if its potential is to be realized. These include the runaway greenhouse, loss of atmosphere by chemical or physical processes, and long-lasting global glaciation. In this lecture I will present research on the climate dynamics governing such processes, with particular emphasis on the lessons to be learned from the cases of Early Mars and the Neoproterozoic Snowball Earth.

Subglacial hydrothermal alteration minerals in Jökulhlaup deposits of Southern Iceland, with implications for detecting past or present habitable environments on Mars.

Science.gov (United States)

Warner, Nicholas H; Farmer, Jack D

2010-06-01

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 martian floods, the Holocene sandurs of Iceland are dominated by basaltic clasts derived from the subglacial environment and deposited during jökulhlaups. Palagonite tuffs and breccias, present within the deposits, represent the primary alteration lithology. The surface abundance of palagonite on the sandurs is 1-20%. X-ray diffraction (XRD) analysis of palagonite breccias confirms a mineral assemblage of zeolites, smectites, low-quartz, and kaolinite. Oriented powder X-ray diffractograms (habitable environments for microbial life may be found.

Widen the belt of habitability!

Science.gov (United States)

Möhlmann, D

2012-06-01

Among the key-parameters to characterize habitability are presence or availability of liquid water, an appropriate temperature range, and the time scale of reference. These criteria for habitability are discussed and described from the point of view of water- and ice-physics, and it is shown that liquid water may exist in the sub-surfaces of planetary bodies like Mars, and possibly of inner asteroids and internally heated ice-moons. Water can remain fluid there also at temperatures far below the "canonical" 0 °C. This behaviour is made possible as a consequence of the freezing point depression due to salty solutes in water or "brines", as they can be expected to exist in nature more frequently than pure liquid water. On the other hand, low temperatures cause a slowing down of chemical processes, as can be described by Arrhenius's relation. The resulting smaller reaction rates probably will have the consequence to complicate the detection of low-temperature life processes, if they exist. Furthermore, the adaptation potential of life is to be mentioned in this context as a yet partially unknown process. Resulting recommendations are given to improve the use of criteria to characterize habitable conditions.

MAVEN Observations of Atmospheric Loss at Mars

Science.gov (United States)

Curry, Shannon; Luhmann, Janet; Jakosky, Bruce M.; Brain, David; LeBlanc, Francis; Modolo, Ronan; Halekas, Jasper S.; Schneider, Nicholas M.; Deighan, Justin; McFadden, James; Espley, Jared R.; Mitchell, David L.; Connerney, J. E. P.; Dong, Yaxue; Dong, Chuanfei; Ma, Yingjuan; Cohen, Ofer; Fränz, Markus; Holmström, Mats; Ramstad, Robin; Hara, Takuya; Lillis, Robert J.

2016-06-01

The Mars Atmosphere and Volatile EvolutioN (MAVEN) mission has been making observations of the Martian upper atmosphere and its escape to space since November 2014. The subject of atmospheric loss at terrestrial planets is a subject of intense interest not only because of the implications for past and present water reservoirs, but also for its impacts on the habitability of a planet. Atmospheric escape may have been especially effective at Mars, relative to Earth or Venus, due to its smaller size as well as the lack of a global dynamo magnetic field. Not only is the atmosphere less gravitationally bound, but also the lack of global magnetic field allows the impinging solar wind to interact directly with the Martian atmosphere. When the upper atmosphere is exposed to the solar wind, planetary neutrals can be ionized and 'picked up' by the solar wind and swept away.Both neutral and ion escape have played significant roles the long term climate change of Mars, and the MAVEN mission was designed to directly measure both escaping planetary neutrals and ions with high energy, mass, and time resolution. We will present 1.5 years of observations of atmospheric loss at Mars over a variety of solar and solar wind conditions, including extreme space weather events. We will report the average ion escape rate and the spatial distribution of escaping ions as measured by MAVEN and place them in context both with previous measurements of ion loss by other spacecraft (e.g. Phobos 2 and Mars Express) and with estimates of neutral escape rates by MAVEN. We will then report on the measured variability in ion escape rates with different drivers (e.g. solar EUV, solar wind pressure, etc.) and the implications for the total ion escape from Mars over time. Additionally, we will also discuss the implications for atmospheric escape at exoplanets, particularly weakly magnetized planetary bodies orbiting M-dwarfs, and the dominant escape mechanisms that may drive atmospheric erosion in other

Mars 2020 Rover SHERLOC Calibration Target

Science.gov (United States)

Graff, Trevor; Fries, Marc; Burton, Aaron; Ross, Amy; Larson, Kristine; Garrison, Dan; Calaway, Mike; Tran, Vinh; Bhartia, Roh; Beegle, Luther

2016-01-01

The Scanning Habitable Environments with Raman & Luminescence for Organics & Chemicals (SHERLOC) instrument is a deep ultraviolet (UV) Raman Fluorescence instrument selected as part of the Mars 2020 rover instrument suite. SHERLOC will be mounted on the rover arm and its primary role is to identify carbonaceous species in martian samples. The SHERLOC instrument requires a calibration target which is being designed and fabricated at JSC as part of our continued science participation in Mars robotic missions. The SHERLOC calibration target will address a wide range of NASA goals to include basic science of interest to both the Science Mission Directorate and Human Exploration and Operations Mission Directorate.

Utilization of a terrestrial cyanobacterium, Nostoc sp. HK-01, for space habitation

Science.gov (United States)

Kimura, Shunta; Tomita-Yokotani, Kaori; Arai, Mayumi; Yamashita, Masamichi; Katoh, Hiroshi; Ajioka, Reiko; Inoue, Kotomi

2016-07-01

A terrestrial cyanobacterium, Nostoc sp. HK-01 (hereafter HK-01), has several useful abilities for space habitation; photosynthesis, nitrogen fixation, and space environmental tolerances to vacuum, UV, gamma-ray, heavy particle beam, low and high temperature. Space environmental tolerances are important for transportation to Mars. HK-01 can grow on Martian regolith simulant (MRS) in vitro. Furthermore, HK-01 is useful as food. HK-01 may be utilized as oxygen supply, soil formation and food material for bio-chemical circulation in closed bio-ecosystems, including space habitation such as Mars. HK-01 was adopted as a biological material for the "TANPOPO" mission (JAXA et al.,), because of their high environmental tolerances. The "TANPOPO" mission is performing the space exposure experiments on the Japan Experimental Module (JEM) of the International Space Station (ISS). The results of these experiments will show the ability of HK-01 to survive in space.

MAGNETIC SHIELDING OF EXOMOONS BEYOND THE CIRCUMPLANETARY HABITABLE EDGE

International Nuclear Information System (INIS)

Heller, René; Zuluaga, Jorge I.

2013-01-01

With most planets and planetary candidates detected in the stellar habitable zone (HZ) being super-Earths and gas giants rather than Earth-like planets, we naturally wonder if their moons could be habitable. The first detection of such an exomoon has now become feasible, and due to observational biases it will be at least twice as massive as Mars. However, formation models predict that moons can hardly be as massive as Earth. Hence, a giant planet's magnetosphere could be the only possibility for such a moon to be shielded from cosmic and stellar high-energy radiation. Yet, the planetary radiation belt could also have detrimental effects on exomoon habitability. Here we synthesize models for the evolution of the magnetic environment of giant planets with thresholds from the runaway greenhouse (RG) effect to assess the habitability of exomoons. For modest eccentricities, we find that satellites around Neptune-sized planets in the center of the HZ around K dwarf stars will either be in an RG state and not be habitable, or they will be in wide orbits where they will not be affected by the planetary magnetosphere. Saturn-like planets have stronger fields, and Jupiter-like planets could coat close-in habitable moons soon after formation. Moons at distances between about 5 and 20 planetary radii from a giant planet can be habitable from an illumination and tidal heating point of view, but still the planetary magnetosphere would critically influence their habitability

MAGNETIC SHIELDING OF EXOMOONS BEYOND THE CIRCUMPLANETARY HABITABLE EDGE

Energy Technology Data Exchange (ETDEWEB)

Heller, René [McMaster University, Department of Physics and Astronomy, Hamilton, ON L8S 4M1 (Canada); Zuluaga, Jorge I., E-mail: rheller@physics.mcmaster.ca, E-mail: jzuluaga@fisica.udea.edu.co [FACom - Instituto de Física - FCEN, Universidad de Antioquia, Calle 70 No. 52-21, Medellín (Colombia)

2013-10-20

With most planets and planetary candidates detected in the stellar habitable zone (HZ) being super-Earths and gas giants rather than Earth-like planets, we naturally wonder if their moons could be habitable. The first detection of such an exomoon has now become feasible, and due to observational biases it will be at least twice as massive as Mars. However, formation models predict that moons can hardly be as massive as Earth. Hence, a giant planet's magnetosphere could be the only possibility for such a moon to be shielded from cosmic and stellar high-energy radiation. Yet, the planetary radiation belt could also have detrimental effects on exomoon habitability. Here we synthesize models for the evolution of the magnetic environment of giant planets with thresholds from the runaway greenhouse (RG) effect to assess the habitability of exomoons. For modest eccentricities, we find that satellites around Neptune-sized planets in the center of the HZ around K dwarf stars will either be in an RG state and not be habitable, or they will be in wide orbits where they will not be affected by the planetary magnetosphere. Saturn-like planets have stronger fields, and Jupiter-like planets could coat close-in habitable moons soon after formation. Moons at distances between about 5 and 20 planetary radii from a giant planet can be habitable from an illumination and tidal heating point of view, but still the planetary magnetosphere would critically influence their habitability.

Nanophase Carbonates on Mars: Implications for Carbonate Formation and Habitability

Science.gov (United States)

Archer, P. Douglas, Jr.; Lauer, H. Vern; Ming, Douglas W.; Niles, Paul B.; Morris, Richard V.; Rampe, Elizabeth B.; Sutter, Brad

2014-01-01

Despite having an atmosphere composed primarily of CO2 and evidence for abundant water in the past, carbonate minerals have only been discovered in small amounts in martian dust [1], in outcrops of very limited extent [2, 3], in soils in the Northern Plains (the landing site of the 2007 Phoenix Mars Scout Mission) [4] and may have recently been detected in aeolian material and drilled and powdered sedimentary rock in Gale Crater (the Mars Science Laboratory [MSL] landing site) [5]. Thermal analysis of martian soils by instruments on Phoenix and MSL has demonstrated a release of CO2 at temperatures as low as 250-300 degC, much lower than the traditional decomposition temperatures of calcium or magnesium carbonates. Thermal decomposition temperature can depend on a number of factors such as instrument pressure and ramp rate, and sample particle size [6]. However, if the CO2 released at low temperatures is from carbonates, small particle size is the only effect that could have such a large impact on decomposition temperature, implying the presence of extremely fine-grained (i.e., "nanophase" or clay-sized) carbonates. We hypothesize that this lower temperature release is the signature of small particle-sized (clay-sized) carbonates formed by the weathering of primary minerals in dust or soils through interactions with atmospheric water and carbon dioxide and that this process may persist under current martian conditions. Preliminary work has shown that clay-sized carbonate grains can decompose at much lower temperatures than previously thought. The first work took carbonate, decomposed it to CaO, then flowed CO2 over these samples held at temperatures >100 degC to reform carbonates. Thermal analysis confirmed that carbonates were indeed formed and transmission electron microsopy was used to determine crystal sized were on the order of 10 nm. The next step used minerals such as diopside and wollastonite that were sealed in a glass tube with a CO2 and H2O source. After

Past, present, and future life on Mars

Science.gov (United States)

McKay, C. P.

1998-01-01

Although the Viking results indicated that the surface of Mars is dry and lifeless, there is direct geomorphological evidence that Mars had large amounts of liquid water on its surface in the past. From a biological perspective the existence of liquid water, by itself, motivates the question of the origin of life on Mars. One of the martian meteorites dates back to this early period and may contain evidence consistent with life. The Mars environment 3.5 to 4.0 Gyr ago was comparable to that on the Earth at this time in that both contained liquid water. Life had originated on Earth and reached a fair degree of biological sophistication by 3.5 Gyr ago. To determine if life similarly arose on Mars may require extensive robotic exploration and ultimately human exploration. Intensive exploration of Mars will require a continued presence on the Martian surface and the development of a self sustaining community in which humans can live and work for very long periods of time. A permanent Mars research station can obtain its life support requirements directly from the martian environment enabling a high degree of self-sufficiency. In the longer term, it is possible that in the future we might restore a habitable climate on Mars, returning it to the life-bearing state it may have enjoyed early in its history.

Development of Life on Early Mars

Science.gov (United States)

Gibson, Everett K.; McKay, David S.; Thomas-Keprta, Kathie L.; Clemett, Simon J.; Wentworth, Susan J.

2009-01-01

Exploration of Mars has begun to unveil the history of the planet. Combinations of remote sensing, in situ compositional measurements and photographic observations have shown Mars had a dynamic and active geologic evolution. Mars geologic evolution encompassed conditions that were suitable for supporting life. A habitable planet must have water, carbon and energy sources along with a dynamic geologic past. Mars meets all of these requirements. The first 600 My of Martian history were ripe for life to develop because of the abundance of (i) Water- as shown by carved canyons and oceans or lakes with the early presence of near surface water shown by precipitated carbonates in ALH84001, well-dated at 3.9 Gy, (ii) Energy from the original accretional processes, a molten core which generated a strong magnetic field leaving a permanent record in the early crust, active volcanism continuing throughout Martian history, and continuing impact processes, (iii) Carbon, water and a likely thicker atmosphere from extensive volcanic outgassing (i.e. H20, CO2, CH4, CO, O2, N2, H2S, SO2, etc.) and (iv) crustal tectonics as revealed by faulting and possible plate movement reflected by the magnetic pattern in the crust [1]. The question arises: "Why would life not develop from these favorable conditions on Mars in its first 600 My?" During this period, environmental near-surface conditions on Mars were more favorable to life than at any later time. Standing bodies of water, precipitation and flowing surface water, and possibly abundant hydrothermal energy would favor the formation of early life. (Even if life developed elsewhere on Earth, Venus, or on other bodies-it was transported to Mars where surface conditions were suitable for life to evolve). The commonly stated requirement that life would need hundreds of millions of year to get started is only an assumption; we know of no evidence that requires such a long interval for the development of life, if the proper habitable

The challenges of co-developing a behaviour change app that aimed to make physical activity a habit

Directory of Open Access Journals (Sweden)

Alice S Forster

2016-01-01

Developers of behaviour change apps must balance the demands of users that will make using the app a habit, while retaining the ingredients necessary for the app to achieve its purpose. Mixed methods provide a rich data set with which to base app development and greater confidence that the app will meet the needs of users in terms of social networking and privacy.

Biosignatures on Mars: What, Where, and How? Implications for the Search for Martian Life.

Science.gov (United States)

Westall, Frances; Foucher, Frédéric; Bost, Nicolas; Bertrand, Marylène; Loizeau, Damien; Vago, Jorge L; Kminek, Gerhard; Gaboyer, Frédéric; Campbell, Kathleen A; Bréhéret, Jean-Gabriel; Gautret, Pascale; Cockell, Charles S

2015-11-01

The search for traces of life is one of the principal objectives of Mars exploration. Central to this objective is the concept of habitability, the set of conditions that allows the appearance of life and successful establishment of microorganisms in any one location. While environmental conditions may have been conducive to the appearance of life early in martian history, habitable conditions were always heterogeneous on a spatial scale and in a geological time frame. This "punctuated" scenario of habitability would have had important consequences for the evolution of martian life, as well as for the presence and preservation of traces of life at a specific landing site. We hypothesize that, given the lack of long-term, continuous habitability, if martian life developed, it was (and may still be) chemotrophic and anaerobic. Obtaining nutrition from the same kinds of sources as early terrestrial chemotrophic life and living in the same kinds of environments, the fossilized traces of the latter serve as useful proxies for understanding the potential distribution of martian chemotrophs and their fossilized traces. Thus, comparison with analog, anaerobic, volcanic terrestrial environments (Early Archean >3.5-3.33 Ga) shows that the fossil remains of chemotrophs in such environments were common, although sparsely distributed, except in the vicinity of hydrothermal activity where nutrients were readily available. Moreover, the traces of these kinds of microorganisms can be well preserved, provided that they are rapidly mineralized and that the sediments in which they occur are rapidly cemented. We evaluate the biogenicity of these signatures by comparing them to possible abiotic features. Finally, we discuss the implications of different scenarios for life on Mars for detection by in situ exploration, ranging from its non-appearance, through preserved traces of life, to the presence of living microorganisms. Mars-Early Earth-Anaerobic chemotrophs

Assessment of MARS for Direct Contact Condensation in the Core Make-up Tank

International Nuclear Information System (INIS)

Park, Keun Tae; Park, Ik Kyu; Lee, Seung Wook

2013-01-01

In order to improve safety features under loss of coolant accident (LOCA) conditions, in many advanced light water reactors, gravity driven passive safety injection systems (PSISs) replace active pump driven emergency core cooling systems. Among various PSISs, the core make-up tank (CMT) with the pressure balancing line (PBL) and the coolant injection line (IL) represents an effective means of providing core cooling. Because the fluid is always sensing the reactor coolant system (RCS) through the PBL connecting the inlet of the CMT to the pressurizer in the case of CP1300 or to the cold legs in the case of AP600/1000, the CMT can provide cold water at any RCS pressure by gravity force. However, after the initiation of LOCAs, if the injection (or isolation) valve is opened, and the steam from the RCS is jetting into the highly subcooled liquid in the CMT and the enhanced interfacial area results in rapid condensation, which in turn, causes a rapid pressure drop in the CMT. As a result, the CMT pressure becomes less than the RCS pressure, and the injection of the CMT can be delayed until the CMT pressure builds up due to greatly reduced condensation in the CMT by the thermal stratification. In order to identify the parameters having significant effects on the gravity-driven injection and the major condensation modes, Lee and No (1998) conducted the separated effect tests of CMT with a small-scale facility. MARS has been developed as a multi-dimensional thermal-hydraulic (TH) system analysis code for the realistic simulation of two-phase TH transients for pressurized water reactor plants. As the backbones for the MARS code, the RELAP5/MOD3.2 and the COB-RA-TF codes were adopted. Recently, Chun et al. (2013) evaluated performance of the SMART passive safety system for SBLOCA using MARS code. However, it is not clarified that MARS can simulate properly the direct contact condensation in the CMT. Thus, in this study, we assess the analysis capability of the MARS code for

Person autonomy and voluntariness as important factors in motivation, decision making, and astronaut safety: First results from the Mars500 LODGEAD study

Science.gov (United States)

Baarsen, Bernadette van

2013-06-01

The present study aims to explore the influence of person autonomy and voluntariness on the level and orientation of motivation and decision making of crew members who live and work in extreme isolated conditions such as during long-term space flights. Motivation has been related to positive behavioural (e.g., goal-orientation), cognitive (e.g., attention), and psychological (e.g., well-being) outcomes and is likely to be relevant for safe and favourable extraterrestrial life- and working-conditions. The study has been carried out within the scope of the Mars500 study which includes a Mars mission simulation of 105 (pilot study) and 520 (main study) days and involves a multi-national crew of 6 men who lived and worked in hermetically sealed modules in the IBMP facilities in Moscow. Data have been collected by the use of questionnaires that evaluate the Mars experiment in terms of, e.g. information received (e.g., "My experiences here are in line with what I was told during the selection and instruction procedure"), perceived social pressure (e.g., "I don't feel free to make my own decisions"), and personal challenge (e.g., "I think that joining the first Mars mission would be a major challenge for me"). It is hypothesised that stronger (1) perceived information consistency, (2) personal expectation consistency, (3) perceived voluntariness, and (4) experienced freedom of choice will be indicative of higher motivation levels. The results will be interpreted in the light of communication, decision making processes, and mission safety. Also, moral expectations and ethical considerations regarding future participation in long duration Human missions such as Mars will be discussed. We will make use of descriptive, longitudinal pattern analyses and correlations.

Astrobiology in the Field: Studying Mars by Analogue Expeditions on Earth

Science.gov (United States)

Conrad, Pamela G.

2011-01-01

We will present a strategy for how one prepares to engage in fieldwork on another planets by practicing in analogous environments on the Earth, including at Mono Lake. As an example, we will address the problem of how to study the habitability of an environment when you have no idea what kind of life might be there to exploit it. This will all be related to the upcoming launch of the Mars Science Laboratory to Mars in late November this year.

Evolved Gas Analysis of Mars Analog Samples from the Arctic Mars Analog Svalbard Expedition: Implications for Analyses by the Mars Science Laboratory

Science.gov (United States)

McAdam, A.; Stern, J. C.; Mahaffy, P. R.; Blake, D. F.; Bristow, T.; Steele, A.; Amundsen, H. E. F.

2012-01-01

The 2011 Arctic Mars Analog Svalbard Expedition (AMASE) investigated several geologic settings on Svalbard, using methodologies and techniques being developed or considered for future Mars missions, such as the Mars Science Laboratory (MSL). The Sample Analysis at Mars (SAM) instrument suite on MSL consists of a quadrupole mass spectrometer (QMS), a gas chromatograph (GC), and a tunable laser spectrometer (TLS), which analyze gases created by pyrolysis of samples. During AMASE, a Hiden Evolved Gas Analysis-Mass Spectrometer (EGA-MS) system represented the EGA-QMS capability of SAM. Another MSL instrument, CheMin, will use x-ray diffraction (XRD) and x-ray fluorescence (XRF) to perform quantitative mineralogical characterization of samples. Field-portable versions of CheMin were used during AMASE. AMASE 2011 sites spanned a range of environments relevant to understanding martian surface materials, processes and habitability. They included the basaltic Sverrefjell volcano, which hosts carbonate globules, cements and coatings, carbonate and sulfate units at Colletth0gda, Devonian sandstone redbeds in Bockfjorden, altered basaltic lava delta deposits at Mt. Scott Keltie, and altered dolerites and volcanics at Botniahalvoya. Here we focus on SAM-like EGA-MS of a subset of the samples, with mineralogy comparisons to CheMin team results. The results allow insight into sample organic content as well as some constraints on sample mineralogy.

Studies of Young Hawai'ian Lava Tubes: Implications for Planetary Habitability and Human Exploration

Science.gov (United States)

McAdam, Amy; Bleacher, Jacob; Young, Kelsey; Johnson, Sarah Stewart; Needham, Debra; Schmerr, Nicholas; Shiro, Brian; Garry, Brent; Whelley, Patrick; Knudson, Christine;

Hydrated Minerals and Evaporites as Key Targets for a Mars Sample Return Mission

Science.gov (United States)

Adeli, S.; Hauber, E.; Jaumann, R.

2018-04-01

Here we focus on hydrated minerals and evaporites as paleo-environment indicators with preservation capacity. Thus, samples from these materials would increase our knowledge about the past aqueous activities of Mars and its habitability potentials.

Mars' surface radiation environment measured with the Mars science laboratory's curiosity rover

NARCIS (Netherlands)

Hassler, D.M.; Zeitlin, C.; Wimmer-Schweingruber, R.F.; Ehresmann, B.; Rafkin, S.; Eigenbrode, J.L.; Brinza, D.E.; Weigle, G.; Böttcher, S.; Böhm, E.; Burmeister, S.; Guo, J.; Köhler, J.; Martin, C.; Reitz, G.; Cucinotta, F.A.; Kim, M.-H.; Grinspoon, D.; Bullock, M.A.; Posner, A.; Gómez-Elvira, J.; Vasavada, A.; Grotzinger, J.P.; MSL Science Team, the|info:eu-repo/dai/nl/292012217

2014-01-01

The Radiation Assessment Detector (RAD) on the Mars Science Laboratory’s Curiosity rover began making detailed measurements of the cosmic ray and energetic particle radiation environment on the surface of Mars on 7 August 2012. We report and discuss measurements of the absorbed dose and dose

GLIESE 581D IS THE FIRST DISCOVERED TERRESTRIAL-MASS EXOPLANET IN THE HABITABLE ZONE

International Nuclear Information System (INIS)

Wordsworth, Robin D.; Forget, Francois; Millour, Ehouarn; Charnay, Benjamin; Madeleine, Jean-Baptiste; Selsis, Franck

2011-01-01

It has been suggested that the recently discovered exoplanet GJ581d might be able to support liquid water due to its relatively low mass and orbital distance. However, GJ581d receives 35% less stellar energy than Mars and is probably locked in tidal resonance, with extremely low insolation at the poles and possibly a permanent night side. Under such conditions, it is unknown whether any habitable climate on the planet would be able to withstand global glaciation and/or atmospheric collapse. Here we present three-dimensional climate simulations which demonstrate that GJ581d will have a stable atmosphere and surface liquid water for a wide range of plausible cases, making it the first confirmed super-Earth (exoplanet of 2-10 Earth masses) in the habitable zone. We find that atmospheres with over 10 bar CO 2 and varying amounts of background gas (e.g., N 2 ) yield global mean temperatures above 0 0 C for both land and ocean-covered surfaces. Based on the emitted IR radiation calculated by the model, we propose observational tests that will allow these cases to be distinguished from other possible scenarios in the future.

Shape Your Family's Habits: Helping Kids Make Healthy Choices

Science.gov (United States)

... kids to be active. When it comes to food and physical activity, what you say and do around your children can have a lasting effect. Work ... Choices Help Kids Form Healthy Habits Be a role model. Eat healthy family meals together. Walk or ride ...

Camelot 3: Habitability criteria space research and design studio

Science.gov (United States)

Arroyo, F.; Budet, O.; Garcia, A.; Lee, J.; Lopez, R.; Lugo, R.; Mateo, A.; Mellado, R.; Mendez, H.; Ortiz, N.

1989-01-01

Acknowledging the importance of human beings on a mission to Mars, the University of Puerto Rico studied both psychological and physiological aspects. Different conditions necessary for human health and well-being were considered. As a result, habitability criteria were developed. The criteria are as follows: personal identification; social interaction; unpredictable conditions; contact with nature; mental landscapes; privacy; equalitarian conditions; variety; functionality; sensory stimulation; music and environmental sound; stability and security; comfort; and sense of orientation.

Searching for brine on Mars using Raman spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Fischer, E.

2016-07-01

In the last few years, water ice and perchlorate salts capable of melting this ice and producing liquid solutions have been discovered at the surface and shallow subsurface of Mars. In addition to via melting of ice, perchlorate salts may also form liquid solutions by absorbing water vapor when the relative humidity is above a certain threshold in a process known as deliquescence. Formed either by melting or deliquescence, liquid solutions (brine) are the most likely way of liquid water activity on the Martian surface and in the shallow subsurface and are therefore important to understand the habitability of Mars. Using Raman spectroscopy, we provide reference spectra of various mixing states of liquid water, water ice and calcium perchlorate, all of which can occur during brine formation. We focus on the perchlorate symmetric stretching band and the O-H stretching vibrational band to distinguish brine from crystalline salt and water ice. We show that perchlorate brines can be identified by analyzing the peaks and their widths in the decomposed Raman spectra of the investigated samples. This serves as an important reference for future in-situ Raman spectrometers on Mars, such as those on the ExoMars and Mars 2020 rovers and can aid in the detection of brine formation on Mars. (Author)

Astrobiology Results from ILEWG EuroMoonMars Analogue Field Research

Science.gov (United States)

Foing, Bernard H.

We give an update on the astrobiology results from a series of field research campaigns (ILEWG EuroMoonMars) in the extreme environment of the Utah desert. These are relevant to prepare future lunar landers and polar sample return missions, interpret Moon-Mars data (eg SMART1, LRO, Mars Express, MRO, MER, MSL), study habitability and astrobiology in Moon-Mars environments, or to test human-robotic surface EVA or base operations. In the frame of ILEWG EuroMoonMars campaigns (2009 to 2013) we deployed at Mars Desert Research station near Hanksville Utah, a suite of instruments and techniques [0, 1, 2, 9-11] including sample collection, context imaging from re-mote to local and microscale, drilling, spectrometers and life sensors. We analyzed how geological and geo-chemical evolution affected local parameters (mineralogy, organics content, environment variations) and the habitability and signature of organics and biota. Results: Among the important findings are the diversity in the composition of soil samples even when collected in close proximity, the low abundances of detectable PAHs and amino acids and the presence of biota of all three domains of life with significant heterogeneity. An extraordinary variety of putative extremophiles was observed [3,4,9]. A dominant factor seems to be soil porosity and lower clay-sized particle content [6-8]. A protocol was developed for sterile sampling, contamination issues, and the diagnostics of biodiversity via PCR and DGGE analysis in soils and rocks samples [10, 11]. We compare the 2009 campaign results [0-9] to new measurements from 2010-2013 campaigns relevant to: comparison between remote sensing and in-situ measurements; the study of minerals; the detection of organics and signs of life. We acknowledge team members and supporting institutes: B.H. Foing (1, 2, 6), C. Stoker (3), P. Ehrenfreund (4, 5), I. Rammos (2), L. Rodrigues (2), A. Svendsen (2), D. Oltheten (2), I. Schlacht (2), K. Nebergall (6), M. Battler (6, 7), H

Mars Aqueous Processing System

Science.gov (United States)

Berggren, Mark; Wilson, Cherie; Carrera, Stacy; Rose, Heather; Muscatello, Anthony; Kilgore, James; Zubrin, Robert

2012-01-01

The goal of the Mars Aqueous Processing System (MAPS) is to establish a flexible process that generates multiple products that are useful for human habitation. Selectively extracting useful components into an aqueous solution, and then sequentially recovering individual constituents, can obtain a suite of refined or semi-refined products. Similarities in the bulk composition (although not necessarily of the mineralogy) of Martian and Lunar soils potentially make MAPS widely applicable. Similar process steps can be conducted on both Mars and Lunar soils while tailoring the reaction extents and recoveries to the specifics of each location. The MAPS closed-loop process selectively extracts, and then recovers, constituents from soils using acids and bases. The emphasis on Mars involves the production of useful materials such as iron, silica, alumina, magnesia, and concrete with recovery of oxygen as a byproduct. On the Moon, similar chemistry is applied with emphasis on oxygen production. This innovation has been demonstrated to produce high-grade materials, such as metallic iron, aluminum oxide, magnesium oxide, and calcium oxide, from lunar and Martian soil simulants. Most of the target products exhibited purities of 80 to 90 percent or more, allowing direct use for many potential applications. Up to one-fourth of the feed soil mass was converted to metal, metal oxide, and oxygen products. The soil residue contained elevated silica content, allowing for potential additional refining and extraction for recovery of materials needed for photovoltaic, semiconductor, and glass applications. A high-grade iron oxide concentrate derived from lunar soil simulant was used to produce a metallic iron component using a novel, combined hydrogen reduction/metal sintering technique. The part was subsequently machined and found to be structurally sound. The behavior of the lunar-simulant-derived iron product was very similar to that produced using the same methods on a Michigan iron

NASA Mars 2020 Rover Mission: New Frontiers in Science

Science.gov (United States)

Calle, Carlos I.

2014-01-01

The Mars 2020 rover mission is the next step in NASAs robotic exploration of the red planet. The rover, based on the Mars Science Laboratory Curiosity rover now on Mars, will address key questions about the potential for life on Mars. The mission would also provide opportunities to gather knowledge and demonstrate technologies that address the challenges of future human expeditions to Mars.Like the Mars Science Laboratory rover, which has been exploring Mars since 2012, the Mars 2020 spacecraft will use a guided entry, descent, and landing system which includes a parachute, descent vehicle, and, during the provides the ability to land a very large, heavy rover on the surface of Mars in a more precise landing area. The Mars 2020 mission is designed to accomplish several high-priority planetary science goals and will be an important step toward meeting NASAs challenge to send humans to Mars in the 2030s. The mission will conduct geological assessments of the rover's landing site, determine the habitability of the environment, search for signs of ancient Martian life, and assess natural resources and hazards for future human explorers. The science instruments aboard the rover also will enable scientists to identify and select a collection of rock and soil samples that will be stored for potential return to Earth in the future. The rover also may help designers of a human expedition understand the hazards posed by Martian dust and demonstrate how to collect carbon dioxide from the atmosphere, which could be a valuable resource for producing oxygen and rocket fuel.

Volatiles and Isotopes and the Exploration of Ancient and Modern Martian Habitability with the Curiosity Rover

Science.gov (United States)

Mhaffy, P. R.

2015-01-01

The Mars Science Laboratory Mission was designed to pave the way for the study of life beyond Earth through a search for a habitable environment in a carefully selected landing site on Mars. Its ongoing exploration of Gale Crater with the Curiosity Rover has provided a rich data set that revealed such an environment in an ancient lakebed [1]. Volatile and isotope measurements of both the atmosphere and solids contribute to our growing understanding of both modern and ancient environments.

Biological Characterization of Microenvironments in a Hypersaline Cold Spring Mars Analog

Directory of Open Access Journals (Sweden)

Haley M. Sapers

2017-12-01

Full Text Available While many habitable niches on Earth are characterized by permanently cold conditions, little is known about the spatial structure of seasonal communities and the importance of substrate-cell associations in terrestrial cyroenvironments. Here we use the 16S rRNA gene as a marker for genetic diversity to compare two visually distinct but spatially integrated surface microbial mats on Axel Heiberg Island, Canadian high arctic, proximal to a perennial saline spring. This is the first study to describe the bacterial diversity in microbial mats on Axel Heiberg Island. The hypersaline springs on Axel Heiberg represent a unique analog to putative subsurface aquifers on Mars. The Martian subsurface represents the longest-lived potentially habitable environment on Mars and a better understanding of the microbial communities on Earth that thrive in analog conditions will help direct future life detection missions. The microbial mats sampled on Axel Heiberg are only visible during the summer months in seasonal flood plains formed by melt water and run-off from the proximal spring. Targeted-amplicon sequencing revealed that not only does the bacterial composition of the two mat communities differ substantially from the sediment community of the proximal cold spring, but that the mat communities are distinct from any other microbial community in proximity to the Arctic springs studied to date. All samples are dominated by Gammaproteobacteria: Thiotichales is dominant within the spring samples while Alteromonadales comprises a significant component of the mat communities. The two mat samples differ in their Thiotichales:Alteromonadales ratio and contribution of Bacteroidetes to overall diversity. The red mats have a greater proportion of Alteromonadales and Bacteroidetes reads. The distinct bacterial composition of the mat bacterial communities suggests that the spring communities are not sourced from the surface, and that seasonal melt events create

Solar-Electrochemical Power System for a Mars Mission

Science.gov (United States)

Withrow, Colleen A.; Morales, Nelson

1994-01-01

This report documents a sizing study of a variety of solar electrochemical power systems for the intercenter NASA study known as 'Mars Exploration Reference Mission'. Power systems are characterized for a variety of rovers, habitation modules, and space transport vehicles based on requirements derived from the reference mission. The mission features a six-person crew living on Mars for 500 days. Mission power requirements range from 4 kWe to 120 kWe. Primary hydrogen and oxygen fuel cells, regenerative hydrogen and oxygen fuel cells, sodium sulfur batteries advanced photovoltaic solar arrays of gallium arsenide on germanium with tracking and nontracking mechanisms, and tent solar arrays of gallium arsenide on germanium are evaluated and compared.

X-Ray Diffraction on Mars: Scientific Discoveries Made by the CheMin Instrument

Science.gov (United States)

Rampe, E. B.; Blake, D. F.; Ming, D. W.; Bristow, T. F.

2017-01-01

The Mars Science Laboratory Curiosity landed in Gale crater in August 2012 with the goal to identify and characterize habitable environments on Mars. Curiosity has been studying a series of sedimentary rocks primarily deposited in fluviolacustrine environments approximately 3.5 Ga. Minerals in the rocks and soils on Mars can help place further constraints on these ancient aqueous environments, including pH, salinity, and relative duration of liquid water. The Chemistry and Mineralogy (CheMin) X-ray diffraction and X-ray fluorescence instrument on Curiosity uses a Co X-ray source and charge-coupled device detector in transmission geometry to collect 2D Debye-Scherrer ring patterns of the less than 150 micron size fraction of drilled rock powders or scooped sediments. With an angular range of approximately 2.52deg 20 and a 20 resolution of approximately 0.3deg, mineral abundances can be quantified with a detection limit of approximately 1-2 wt. %. CheMin has returned quantitative mineral abundances from 16 mudstone, sandstone, and aeolian sand samples so far. The mineralogy of these samples is incredibly diverse, suggesting a variety of depositional and diagenetic environments and different source regions for the sediments. Results from CheMin have been essential for reconstructing the geologic history of Gale crater and addressing the question of habitability on ancient Mars.

Habitability and the Multiverse

Science.gov (United States)

Sandora, M. E.

2017-11-01

Are the laws of physics set to maximize the habitability of the universe? We study how plate tectonics, core and mantle composition, homochirality, photosynthesis, and planet size depend on physics, and make predictions for where life will be found.

Similarity of Mars and Mercury for terraforming and settling of people

Science.gov (United States)

Steklov, A. F.; Vidmachenko, A. P.

2018-05-01

We compared the main characteristics of the planets Mars and Mercury in the form normalized on the parameters of the planet Earth. Both planets turned out to be similar and close in terms of terraforming techniques, and conditions of comfortable human habitation in long term endo-planetary stations under the surface of a particular planetoid. Mars and Mercury also turned out to be similar on the vital activity of some other representatives of the Earth's biosphere. Our detailed analysis of the temperature distribution both over the entire surface of these planets, and in the conditions of their diurnal and annual variations on different latitudes and on Mars and on Mercury - showed that each of these planets has its advantages for the first terraforming.

Life on Mars

Science.gov (United States)

McKay, Christopher P.; Cuzzi, Jeffrey (Technical Monitor)

1996-01-01

Although the Viking results may indicate that Mars has no life today, the possibility exists that Mars may hold the best record of the events that led to the origin of life. There is direct geomorphological evidence that in the past Mars had large amounts of liquid water on its surface. Atmospheric models would suggest that this early period of hydrological activity was due to the presence of a thick atmosphere and the resulting warmer temperatures. From a biological perspective the existence of liquid water, by itself motivates the question of the origin of life on Mars. From studies of the Earth's earliest biosphere we know that by 3.5 Gyr. ago, life had originated on Earth and reached a fair degree of biological sophistication. Surface activity and erosion on Earth make it difficult to trace the history of life before the 3.5 Gyr timeframe. If Mars did maintain a clement environment for longer than it took for life to originate on Earth, then the question of the origin of life on Mars follows naturally.

An energy balance concept for habitability.

Science.gov (United States)

Hoehler, Tori M

2007-12-01

Habitability can be formulated as a balance between the biological demand for energy and the corresponding potential for meeting that demand by transduction of energy from the environment into biological process. The biological demand for energy is manifest in two requirements, analogous to the voltage and power requirements of an electrical device, which must both be met if life is to be supported. These requirements exhibit discrete (non-zero) minima whose magnitude is set by the biochemistry in question, and they are increased in quantifiable fashion by (i) deviations from biochemically optimal physical and chemical conditions and (ii) energy-expending solutions to problems of resource limitation. The possible rate of energy transduction is constrained by (i) the availability of usable free energy sources in the environment, (ii) limitations on transport of those sources into the cell, (iii) upper limits on the rate at which energy can be stored, transported, and subsequently liberated by biochemical mechanisms (e.g., enzyme saturation effects), and (iv) upper limits imposed by an inability to use "power" and "voltage" at levels that cause material breakdown. A system is habitable when the realized rate of energy transduction equals or exceeds the biological demand for energy. For systems in which water availability is considered a key aspect of habitability (e.g., Mars), the energy balance construct imposes additional, quantitative constraints that may help to prioritize targets in search-for-life missions. Because the biological need for energy is universal, the energy balance construct also helps to constrain habitability in systems (e.g., those envisioned to use solvents other than water) for which little constraint currently exists.

The CheMin XRD on the Mars Science Laboratory Rover Curiosity: Construction, Operation, and Quantitative Mineralogical Results from the Surface of Mars

Science.gov (United States)

Blake, David F.

2015-01-01

The Mars Science Laboratory mission was launched from Cape Canaveral, Florida on Nov. 26, 2011 and landed in Gale crater, Mars on Aug. 6, 2012. MSL's mission is to identify and characterize ancient "habitable" environments on Mars. MSL's precision landing system placed the Curiosity rover within 2 km of the center of its 20 X 6 km landing ellipse, next to Gale's central mound, a 5,000 meter high pile of laminated sediment which may contain 1 billion years of Mars history. Curiosity carries with it a full suite of analytical instruments, including the CheMin X-ray diffractometer, the first XRD flown in space. CheMin is essentially a transmission X-ray pinhole camera. A fine-focus Co source and collimator transmits a 50µm beam through a powdered sample held between X-ray transparent plastic windows. The sample holder is shaken by a piezoelectric actuator such that the powder flows like a liquid, each grain passing in random orientation through the beam over time. Forward-diffracted and fluoresced X-ray photons from the sample are detected by an X-ray sensitive Charge Coupled Device (CCD) operated in single photon counting mode. When operated in this way, both the x,y position and the energy of each photon are detected. The resulting energy-selected Co Kalpha Debye-Scherrer pattern is used to determine the identities and amounts of minerals present via Rietveld refinement, and a histogram of all X-ray events constitutes an X-ray fluorescence analysis of the sample.The key role that definitive mineralogy plays in understanding the Martian surface is a consequence of the fact that minerals are thermodynamic phases, having known and specific ranges of temperature, pressure and composition within which they are stable. More than simple compositional analysis, definitive mineralogical analysis can provide information about pressure/temperature conditions of formation, past climate, water activity and the like. Definitive mineralogical analyses are necessary to establish

Ancient aliens on mars

CERN Document Server

Bara, Mike

2013-01-01

Best-selling author and Secret Space Program researcher Bara brings us this lavishly illustrated volume on alien structures on Mars. Was there once a vast, technologically advanced civilization on Mars, and did it leave evidence of its existence behind for humans to find eons later? Did these advanced extraterrestrial visitors vanish in a solar system wide cataclysm of their own making, only to make their way to Earth and start anew? Was Mars once as lush and green as the Earth, and teeming with life? Did Mars once orbit a missing member of the solar system, a "Super Earth” that vanished in a disaster that devastated life on Earth and Venus and left us only the asteroid belt as evidence of its once grand existence? Did the survivors of this catastrophe leave monuments and temples behind, arranged in a mathematical precision designed to teach us the Secret of a new physics that could lift us back to the stars? Does the planet have an automated defense shield that swallows up robotic probes if they wander int...

The Last Possible Outposts for Life on Mars.

Science.gov (United States)

Davila, Alfonso F; Schulze-Makuch, Dirk

2016-02-01

The evolution of habitable conditions on Mars is often tied to the existence of aquatic habitats and largely constrained to the first billion years of the planet. Here, we propose an alternate, lasting evolutionary trajectory that assumes the colonization of land habitats before the end of the Hesperian period (ca. 3 billion years ago) at a pace similar to life on Earth. Based on the ecological adaptations to increasing dryness observed in dryland ecosystems on Earth, we reconstruct the most likely sequence of events leading to a late extinction of land communities on Mars. We propose a trend of ecological change with increasing dryness from widespread edaphic communities to localized lithic communities and finally to communities exclusively found in hygroscopic substrates, reflecting the need for organisms to maximize access to atmospheric sources of water. If our thought process is correct, it implies the possibility of life on Mars until relatively recent times, perhaps even the present.

The Sample Analysis at Mars Investigation and Instrument Suite

Science.gov (United States)

Mahaffy, Paul; Webster, Christopher R.; Conrad, Pamela G.; Arvey, Robert; Bleacher, Lora; Brinckerhoff, William B.; Eigenbrode, Jennifer L.; Chalmers, Robert A.; Dworkin, Jason P.; Errigo, Therese;

Science applications of a multispectral microscopic imager for the astrobiological exploration of Mars.

Science.gov (United States)

Núñez, Jorge I; Farmer, Jack D; Sellar, R Glenn; Swayze, Gregg A; Blaney, Diana L

2014-02-01

Future astrobiological missions to Mars are likely to emphasize the use of rovers with in situ petrologic capabilities for selecting the best samples at a site for in situ analysis with onboard lab instruments or for caching for potential return to Earth. Such observations are central to an understanding of the potential for past habitable conditions at a site and for identifying samples most likely to harbor fossil biosignatures. The Multispectral Microscopic Imager (MMI) provides multispectral reflectance images of geological samples at the microscale, where each image pixel is composed of a visible/shortwave infrared spectrum ranging from 0.46 to 1.73 μm. This spectral range enables the discrimination of a wide variety of rock-forming minerals, especially Fe-bearing phases, and the detection of hydrated minerals. The MMI advances beyond the capabilities of current microimagers on Mars by extending the spectral range into the infrared and increasing the number of spectral bands. The design employs multispectral light-emitting diodes and an uncooled indium gallium arsenide focal plane array to achieve a very low mass and high reliability. To better understand and demonstrate the capabilities of the MMI for future surface missions to Mars, we analyzed samples from Mars-relevant analog environments with the MMI. Results indicate that the MMI images faithfully resolve the fine-scale microtextural features of samples and provide important information to help constrain mineral composition. The use of spectral endmember mapping reveals the distribution of Fe-bearing minerals (including silicates and oxides) with high fidelity, along with the presence of hydrated minerals. MMI-based petrogenetic interpretations compare favorably with laboratory-based analyses, revealing the value of the MMI for future in situ rover-mediated astrobiological exploration of Mars. Mars-Microscopic imager-Multispectral imaging-Spectroscopy-Habitability-Arm instrument.

The Force of Habit: Creating and Sustaining a Wellness Lifestyle.

Science.gov (United States)

Nemec, Patricia B; Swarbrick, Margaret A; Merlo, David M

2015-09-01

Regardless of an individual's mental health status, habits are difficult to establish and/or eliminate. Given the importance of good habits to overall health and wellness, nurses and other mental health service providers need to understand the force of habits (positive and negative), factors that make habit change difficult, and approaches that are likely to facilitate building and maintaining good habits. The current article provides a cursory overview of several factors (i.e., motivation, will-power, and rewards) that impact habit formation. Relevant theories and research are presented. Habit formation can be fostered through a careful analysis of current behaviors, specific and measurable short-term goals or objectives, and a detailed action plan. Copyright 2015, SLACK Incorporated.

The early thermal evolution of Mars

Science.gov (United States)

Bhatia, G. K.; Sahijpal, S.

2016-01-01

Hf-W isotopic systematics of Martian meteorites have provided evidence for the early accretion and rapid core formation of Mars. We present the results of numerical simulations performed to study the early thermal evolution and planetary scale differentiation of Mars. The simulations are confined to the initial 50 Myr (Ma) of the formation of solar system. The accretion energy produced during the growth of Mars and the decay energy due to the short-lived radio-nuclides 26Al, 60Fe, and the long-lived nuclides, 40K, 235U, 238U, and 232Th are incorporated as the heat sources for the thermal evolution of Mars. During the core-mantle differentiation of Mars, the molten metallic blobs were numerically moved using Stoke's law toward the center with descent velocity that depends on the local acceleration due to gravity. Apart from the accretion and the radioactive heat energies, the gravitational energy produced during the differentiation of Mars and the associated heat transfer is also parametrically incorporated in the present work to make an assessment of its contribution to the early thermal evolution of Mars. We conclude that the accretion energy alone cannot produce widespread melting and differentiation of Mars even with an efficient consumption of the accretion energy. This makes 26Al the prime source for the heating and planetary scale differentiation of Mars. We demonstrate a rapid accretion and core-mantle differentiation of Mars within the initial ~1.5 Myr. This is consistent with the chronological records of Martian meteorites.

Space agriculture for habitation on Mars with hyper-thermophilic aerobic composting bacteria

Science.gov (United States)

Space Agriculture Task Force; Ishikawa, Y.; Tomita-Yokotani, K.; Hashimoto, H.; Kitaya, Y.; Yamashita, M.; Nagatomo, M.; Oshima, T.; Wada, H.

Manned Mars exploration, especially for extended periods of time, will require recycle of materials to support human life. Here, a conceptual design is developed for a Martian agricultural system driven by biologically regenerative functions. One of the core biotechnologies function is the use of hyper-thermophilic aerobic composting bacterial ecology. These thermophilic bacteria can play an important role in increasing the effectiveness of the processing of human metabolic waste and inedible biomass and of converting them to fertilizer for the cultivation of plants. This microbial technology has been already well established for the purpose of processing sewage and waste materials for small local communities in Japan. One of the characteristics of the technology is that the metabolic heat release that occurs during bacterial fermentation raises the processing temperature sufficiently high at 80 100 °C to support hyper-thermophilic bacteria. Such a hyper-thermophilic system is found to have great capability of decomposing wastes including even their normally recalcitrant components, in a reasonably short period of time and of providing a better quality of fertilizer as an end-product. High quality compost has been shown to be a key element in creating a healthy regenerative food production system. In ground-based studies, the soil microbial ecology after the addition of high quality compost was shown to improve plant growth and promote a healthy symbiosis of arbuscular mycorrhizal fungi. Another advantage of such high processing temperature is the ability to sterilize the pathogenic organisms through the fermentation process and thus to secure the hygienic safety of the system. Plant cultivation is one of the other major systems. It should fully utilize solar energy received on the Martian surface for supplying energy for photosynthesis. Subsurface water and atmospheric carbon dioxide mined on Mars should be also used in the plant cultivation system. Oxygen and

Subsurface water and clay mineral formation during the early history of Mars.

Science.gov (United States)

Ehlmann, Bethany L; Mustard, John F; Murchie, Scott L; Bibring, Jean-Pierre; Meunier, Alain; Fraeman, Abigail A; Langevin, Yves

2011-11-02

Clay minerals, recently discovered to be widespread in Mars's Noachian terrains, indicate long-duration interaction between water and rock over 3.7 billion years ago. Analysis of how they formed should indicate what environmental conditions prevailed on early Mars. If clays formed near the surface by weathering, as is common on Earth, their presence would indicate past surface conditions warmer and wetter than at present. However, available data instead indicate substantial Martian clay formation by hydrothermal groundwater circulation and a Noachian rock record dominated by evidence of subsurface waters. Cold, arid conditions with only transient surface water may have characterized Mars's surface for over 4 billion years, since the early-Noachian period, and the longest-duration aqueous, potentially habitable environments may have been in the subsurface.

Life Support and Habitation and Planetary Protection Workshop

Science.gov (United States)

Hogan, John A. (Editor); Race, Margaret S. (Editor); Fisher, John W. (Editor); Joshi, Jitendra A. (Editor); Rummel, John D. (Editor)

2006-01-01

A workshop entitled "Life Support and Habitation and Planetary Protection Workshop" was held in Houston, Texas on April 27-29, 2005 to facilitate the development of planetary protection guidelines for future human Mars exploration missions and to identify the potential effects of these guidelines on the design and selection of related human life support, extravehicular activity and monitoring and control systems. This report provides a summary of the workshop organization, starting assumptions, working group results and recommendations. Specific result topics include the identification of research and technology development gaps, potential forward and back contaminants and pathways, mitigation alternatives, and planetary protection requirements definition needs. Participants concluded that planetary protection and science-based requirements potentially affect system design, technology trade options, development costs and mission architecture. Therefore early and regular coordination between the planetary protection, scientific, planning, engineering, operations and medical communities is needed to develop workable and effective designs for human exploration of Mars.

Mars Surface Systems Common Capabilities and Challenges for Human Missions

Science.gov (United States)

Toups, Larry; Hoffman, Stephen J.

2016-01-01

This paper describes the current status of common systems and operations as they are applied to actual locations on Mars that are representative of Exploration Zones (EZ) - NASA's term for candidate locations where humans could land, live and work on the Martian surface. Given NASA's current concepts for human missions to Mars, an EZ is a collection of Regions of Interest (ROIs) located within approximately 100 kilometers of a centralized landing site. ROIs are areas that are relevant for scientific investigation and/or development/maturation of capabilities and resources necessary for a sustainable human presence. An EZ also contains a habitation site that will be used by multiple human crews during missions to explore and utilize the ROIs within the EZ. The Evolvable Mars Campaign (EMC), a description of NASA's current approach to these human Mars missions, assumes that a single EZ will be identified within which NASA will establish a substantial and durable surface infrastructure that will be used by multiple human crews. The process of identifying and eventually selecting this single EZ will likely take many years to finalized. Because of this extended EZ selection process it becomes important to evaluate the current suite of surface systems and operations being evaluated for the EMC as they are likely to perform at a variety of proposed EZ locations and for the types of operations - both scientific and development - that are proposed for these candidate EZs. It is also important to evaluate proposed EZs for their suitability to be explored or developed given the range of capabilities and constraints for the types of surface systems and operations being considered within the EMC. Four locations identified in the Mars Exploration Program Analysis Group (MEPAG)'s Human Exploration of Mars Science Analysis Group (HEM-SAG) report are used in this paper as representative of candidate EZs that will emerge from the selection process that NASA has initiated. A field

Searching for Life on Mars Before It Is Too Late.

Science.gov (United States)

Fairén, Alberto G; Parro, Victor; Schulze-Makuch, Dirk; Whyte, Lyle

2017-10-01

Decades of robotic exploration have confirmed that in the distant past, Mars was warmer and wetter and its surface was habitable. However, none of the spacecraft missions to Mars have included among their scientific objectives the exploration of Special Regions, those places on the planet that could be inhabited by extant martian life or where terrestrial microorganisms might replicate. A major reason for this is because of Planetary Protection constraints, which are implemented to protect Mars from terrestrial biological contamination. At the same time, plans are being drafted to send humans to Mars during the 2030 decade, both from international space agencies and the private sector. We argue here that these two parallel strategies for the exploration of Mars (i.e., delaying any efforts for the biological reconnaissance of Mars during the next two or three decades and then directly sending human missions to the planet) demand reconsideration because once an astronaut sets foot on Mars, Planetary Protection policies as we conceive them today will no longer be valid as human arrival will inevitably increase the introduction of terrestrial and organic contaminants and that could jeopardize the identification of indigenous martian life. In this study, we advocate for reassessment over the relationships between robotic searches, paying increased attention to proactive astrobiological investigation and sampling of areas more likely to host indigenous life, and fundamentally doing this in advance of manned missions. Key Words: Contamination-Earth Mars-Planetary Protection-Search for life (biosignatures). Astrobiology 17, 962-970.

Ma_MISS on ExoMars: Mineralogical Characterization of the Martian Subsurface

Science.gov (United States)

De Sanctis, Maria Cristina; Altieri, Francesca; Ammannito, Eleonora; Biondi, David; De Angelis, Simone; Meini, Marco; Mondello, Giuseppe; Novi, Samuele; Paolinetti, Riccardo; Soldani, Massimo; Mugnuolo, Raffaele; Pirrotta, Simone; Vago, Jorge L.; Ma_MISS Team

2017-07-01

The Ma_MISS (Mars Multispectral Imager for Subsurface Studies) experiment is the visible and near infrared (VNIR) miniaturized spectrometer hosted by the drill system of the ExoMars 2020 rover. Ma_MISS will perform IR spectral reflectance investigations in the 0.4-2.2 μm range to characterize the mineralogy of excavated borehole walls at different depths (between 0 and 2 m). The spectral sampling is about 20 nm, whereas the spatial resolution over the target is 120 μm. Making use of the drill's movement, the instrument slit can scan a ring and build up hyperspectral images of a borehole. The main goal of the Ma_MISS instrument is to study the martian subsurface environment. Access to the martian subsurface is crucial to our ability to constrain the nature, timing, and duration of alteration and sedimentation processes on Mars, as well as habitability conditions. Subsurface deposits likely host and preserve H2O ice and hydrated materials that will contribute to our understanding of the H2O geochemical environment (both in the liquid and in the solid state) at the ExoMars 2020 landing site. The Ma_MISS spectral range and sampling capabilities have been carefully selected to allow the study of minerals and ices in situ before the collection of samples. Ma_MISS will be implemented to accomplish the following scientific objectives: (1) determine the composition of subsurface materials, (2) map the distribution of subsurface H2O and volatiles, (3) characterize important optical and physical properties of materials (e.g., grain size), and (4) produce a stratigraphic column that will inform with regard to subsurface geological processes. The Ma_MISS findings will help to refine essential criteria that will aid in our selection of the most interesting subsurface formations from which to collect samples.

COMPARATIVE HABITABILITY OF TRANSITING EXOPLANETS

Energy Technology Data Exchange (ETDEWEB)

Barnes, Rory; Meadows, Victoria S.; Evans, Nicole, E-mail: rory@astro.washington.edu [Astronomy Department, University of Washington, Box 951580, Seattle, WA 98195 (United States)

2015-12-01

Exoplanet habitability is traditionally assessed by comparing a planet’s semimajor axis to the location of its host star’s “habitable zone,” the shell around a star for which Earth-like planets can possess liquid surface water. The Kepler space telescope has discovered numerous planet candidates near the habitable zone, and many more are expected from missions such as K2, TESS, and PLATO. These candidates often require significant follow-up observations for validation, so prioritizing planets for habitability from transit data has become an important aspect of the search for life in the universe. We propose a method to compare transiting planets for their potential to support life based on transit data, stellar properties and previously reported limits on planetary emitted flux. For a planet in radiative equilibrium, the emitted flux increases with eccentricity, but decreases with albedo. As these parameters are often unconstrained, there is an “eccentricity-albedo degeneracy” for the habitability of transiting exoplanets. Our method mitigates this degeneracy, includes a penalty for large-radius planets, uses terrestrial mass–radius relationships, and, when available, constraints on eccentricity to compute a number we call the “habitability index for transiting exoplanets” that represents the relative probability that an exoplanet could support liquid surface water. We calculate it for Kepler objects of interest and find that planets that receive between 60% and 90% of the Earth’s incident radiation, assuming circular orbits, are most likely to be habitable. Finally, we make predictions for the upcoming TESS and James Webb Space Telescope missions.

COMPARATIVE HABITABILITY OF TRANSITING EXOPLANETS

International Nuclear Information System (INIS)

Barnes, Rory; Meadows, Victoria S.; Evans, Nicole

2015-01-01

Exoplanet habitability is traditionally assessed by comparing a planet’s semimajor axis to the location of its host star’s “habitable zone,” the shell around a star for which Earth-like planets can possess liquid surface water. The Kepler space telescope has discovered numerous planet candidates near the habitable zone, and many more are expected from missions such as K2, TESS, and PLATO. These candidates often require significant follow-up observations for validation, so prioritizing planets for habitability from transit data has become an important aspect of the search for life in the universe. We propose a method to compare transiting planets for their potential to support life based on transit data, stellar properties and previously reported limits on planetary emitted flux. For a planet in radiative equilibrium, the emitted flux increases with eccentricity, but decreases with albedo. As these parameters are often unconstrained, there is an “eccentricity-albedo degeneracy” for the habitability of transiting exoplanets. Our method mitigates this degeneracy, includes a penalty for large-radius planets, uses terrestrial mass–radius relationships, and, when available, constraints on eccentricity to compute a number we call the “habitability index for transiting exoplanets” that represents the relative probability that an exoplanet could support liquid surface water. We calculate it for Kepler objects of interest and find that planets that receive between 60% and 90% of the Earth’s incident radiation, assuming circular orbits, are most likely to be habitable. Finally, we make predictions for the upcoming TESS and James Webb Space Telescope missions

In-Space Transportation for NASA's Evolvable Mars Campaign

Science.gov (United States)

Percy, Thomas K.; McGuire, Melissa; Polsgrove, Tara

2015-01-01

As the nation embarks on a new and bold journey to Mars, significant work is being done to determine what that mission and those architectural elements will look like. The Evolvable Mars Campaign, or EMC, is being evaluated as a potential approach to getting humans to Mars. Built on the premise of leveraging current technology investments and maximizing element commonality to reduce cost and development schedule, the EMC transportation architecture is focused on developing the elements required to move crew and equipment to Mars as efficiently and effectively as possible both from a performance and a programmatic standpoint. Over the last 18 months the team has been evaluating potential options for those transportation elements. One of the key aspects of the EMC is leveraging investments being made today in missions like the Asteroid Redirect Mission (ARM) mission using derived versions of the Solar Electric Propulsion (SEP) propulsion systems and coupling them with other chemical propulsion elements that maximize commonality across the architecture between both transportation and Mars operations elements. This paper outlines the broad trade space being evaluated including the different technologies being assessed for transportation elements and how those elements are assembled into an architecture. Impacts to potential operational scenarios at Mars are also investigated. Trades are being made on the size and power level of the SEP vehicle for delivering cargo as well as the size of the chemical propulsion systems and various mission aspects including Inspace assembly and sequencing. Maximizing payload delivery to Mars with the SEP vehicle will better support the operational scenarios at Mars by enabling the delivery of landers and habitation elements that are appropriately sized for the mission. The purpose of this investigation is not to find the solution but rather a suite of solutions with potential application to the challenge of sending cargo and crew to Mars

A Risk-Constrained Multi-Stage Decision Making Approach to the Architectural Analysis of Mars Missions

Science.gov (United States)

Kuwata, Yoshiaki; Pavone, Marco; Balaram, J. (Bob)

2012-01-01

This paper presents a novel risk-constrained multi-stage decision making approach to the architectural analysis of planetary rover missions. In particular, focusing on a 2018 Mars rover concept, which was considered as part of a potential Mars Sample Return campaign, we model the entry, descent, and landing (EDL) phase and the rover traverse phase as four sequential decision-making stages. The problem is to find a sequence of divert and driving maneuvers so that the rover drive is minimized and the probability of a mission failure (e.g., due to a failed landing) is below a user specified bound. By solving this problem for several different values of the model parameters (e.g., divert authority), this approach enables rigorous, accurate and systematic trade-offs for the EDL system vs. the mobility system, and, more in general, cross-domain trade-offs for the different phases of a space mission. The overall optimization problem can be seen as a chance-constrained dynamic programming problem, with the additional complexity that 1) in some stages the disturbances do not have any probabilistic characterization, and 2) the state space is extremely large (i.e, hundreds of millions of states for trade-offs with high-resolution Martian maps). To this purpose, we solve the problem by performing an unconventional combination of average and minimax cost analysis and by leveraging high efficient computation tools from the image processing community. Preliminary trade-off results are presented.

Progressive Climate Change on Titan: Implications for Habitability

Science.gov (United States)

Moore, J. M.; A. D. Howard

2014-01-01

Titan's landscape is profoundly shaped by its atmosphere and comparable in magnitude perhaps with only the Earth and Mars amongst the worlds of the Solar System. Like the Earth, climate dictates the intensity and relative roles of fluvial and aeolian activity from place to place and over geologic time. Thus Titan's landscape is the record of climate change. We have investigated three broad classes of Titan climate evolution hypotheses (Steady State, Progressive, and Cyclic), regulated by the role, sources, and availability of methane. We favor the Progressive hypotheses, which we will outline here, then discuss their implication for habitability.

Exploring Mars

Science.gov (United States)

Breuil, Stéphanie

2016-04-01

Mars is our neighbour planet and has always fascinated humans as it has been seen as a potential abode for life. Knowledge about Mars is huge and was constructed step by step through numerous missions. It could be difficult to describe these missions, the associated technology, the results, the questions they raise, that's why an activity is proposed, that directly interests students. Their production is presented in the poster. Step 1: The main Mars feature and the first Mars explorations using telescope are presented to students. It should be really interesting to present "Mars Canals" from Percival Lowell as it should also warn students against flawed interpretation. Moreover, this study has raised the big question about extra-terrestrial life on Mars for the first time. Using Google Mars is then a good way to show the huge knowledge we have on the planet and to introduce modern missions. Step 2: Students have to choose and describe one of the Mars mission from ESA and NASA. They should work in pairs. Web sites from ESA and NASA are available and the teacher makes sure the main missions will be studied. Step 3: Students have to collect different pieces of information about the mission - When? Which technology? What were the main results? What type of questions does it raise? They prepare an oral presentation in the form they want (role play, academic presentation, using a poster, PowerPoint). They also have to produce playing cards about the mission that could be put on a timeline. Step 4: As a conclusion, the different cards concerning different missions are mixed. Groups of students receive cards and they have to put them on a timeline as fast as possible. It is also possible to play the game "timeline".

Reaching Mars: multi-criteria R&D portfolio selection for Mars exploration technology planning

Science.gov (United States)

Smith, J. H.; Dolgin, B. P.; Weisbin, C. R.

2003-01-01

The exploration of Mars has been the focus of increasing scientific interest about the planet and its relationship to Earth. A multi-criteria decision-making approach was developed to address the question, Given a Mars program composed of mission concepts dependent on a variety of alternative technology development programs, which combination of technologies would enable missions to maximize science return under a constrained budget?.

The Fate of Lipid Biosignatures in a Mars-Analogue Sulfur Stream.

Science.gov (United States)

Tan, Jonathan; Lewis, James M T; Sephton, Mark A

2018-05-15

Past life on Mars will have generated organic remains that may be preserved in present day Mars rocks. The most recent period in the history of Mars that retained widespread surface waters was the late Noachian and early Hesperian and thus possessed the potential to sustain the most evolved and widely distributed martian life. Guidance for investigating late Noachian and early Hesperian rocks is provided by studies of analogous acidic and sulfur-rich environments on Earth. Here we report organic responses for an acid stream containing acidophilic organisms whose post-mortem remains are entombed in iron sulphates and iron oxides. We find that, if life was present in the Hesperian, martian organic records will comprise microbial lipids. Lipids are a potential sizeable reservoir of fossil carbon on Mars, and can be used to distinguish between different domains of life. Concentrations of lipids, and particularly alkanoic or "fatty" acids, are highest in goethite layers that reflect high water-to-rock ratios and thus a greater potential for habitability. Goethite can dehydrate to hematite, which is widespread on Mars. Mars missions should seek to detect fatty acids or their diagenetic products in the oxides and hydroxides of iron associated with sulphur-rich environments.

Mineralogical Results from the Mars Science Laboratory Rover Curiosity

Science.gov (United States)

Blake, David Frederick.

2017-01-01

NASA's CheMin instrument, the first X-ray Diffractometer flown in space, has been operating on Mars for nearly five years. CheMin was first to establish the quantitative mineralogy of the Mars global soil (1). The instrument was next used to determine the mineralogy of a 3.7 billion year old lacustrine mudstone, a result that, together with findings from other instruments on the MSL Curiosity rover, documented the first habitable environment found on another planet (2). The mineralogy of this mudstone from an ancient playa lake was also used to derive the maximum concentration of CO2 in the early Mars atmosphere, a surprisingly low value that calls into question the current theory that CO2 greenhouse warming was responsible for the warm and wet environment of early Mars. CheMin later identified the mineral tridymite, indicative of silica-rich volcanism, in mudstones of the Murray formation on Mt. Sharp. This discovery challenges the paradigm of Mars as a basaltic planet and ushers in a new chapter of comparative terrestrial planetology (3). CheMin is now being used to systematically sample the sedimentary layers that comprise the lower strata of Mt. Sharp, a 5,000 meter sequence of sedimentary rock laid down in what was once a crater lake, characterizing isochemical sediments that through their changing mineralogy, document the oxidation and drying out of the Mars in early Hesperian time.

Electrical power systems for Mars

Science.gov (United States)

Giudici, Robert J.

1986-01-01

Electrical power system options for Mars Manned Modules and Mars Surface Bases were evaluated for both near-term and advanced performance potential. The power system options investigated for the Mission Modules include photovoltaics, solar thermal, nuclear reactor, and isotope power systems. Options discussed for Mars Bases include the above options with the addition of a brief discussion of open loop energy conversion of Mars resources, including utilization of wind, subsurface thermal gradients, and super oxides. Electrical power requirements for Mission Modules were estimated for three basic approaches: as a function of crew size; as a function of electric propulsion; and as a function of transmission of power from an orbiter to the surface of Mars via laser or radio frequency. Mars Base power requirements were assumed to be determined by production facilities that make resources available for follow-on missions leading to the establishment of a permanently manned Base. Requirements include the production of buffer gas and propellant production plants.

Methods and decision making on a Mars rover for identification of fossils

Science.gov (United States)

Eberlein, Susan; Yates, Gigi

1989-01-01

A system for automated fusion and interpretation of image data from multiple sensors, including multispectral data from an imaging spectrometer is being developed. Classical artificial intelligence techniques and artificial neural networks are employed to make real time decision based on current input and known scientific goals. Emphasis is placed on identifying minerals which could indicate past life activity or an environment supportive of life. Multispectral data can be used for geological analysis because different minerals have characteristic spectral reflectance in the visible and near infrared range. Classification of each spectrum into a broad class, based on overall spectral shape and locations of absorption bands is possible in real time using artificial neural networks. The goal of the system is twofold: multisensor and multispectral data must be interpreted in real time so that potentially interesting sites can be flagged and investigated in more detail while the rover is near those sites; and the sensed data must be reduced to the most compact form possible without loss of crucial information. Autonomous decision making will allow a rover to achieve maximum scientific benefit from a mission. Both a classical rule based approach and a decision neural network for making real time choices are being considered. Neural nets may work well for adaptive decision making. A neural net can be trained to work in two steps. First, the actual input state is mapped to the closest of a number of memorized states. After weighing the importance of various input parameters, the net produces an output decision based on the matched memory state. Real time, autonomous image data analysis and decision making capabilities are required for achieving maximum scientific benefit from a rover mission. The system under development will enhance the chances of identifying fossils or environments capable of supporting life on Mars

Preparing for Mars: The Evolvable Mars Campaign 'Proving Ground' Approach

Science.gov (United States)

Bobskill, Marianne R.; Lupisella, Mark L.; Mueller, Rob P.; Sibille, Laurent; Vangen, Scott; Williams-Byrd, Julie

2015-01-01

provide the foundation required to enable a variety of possible destinations and missions consistent with the Evolvable Mars Campaign.. The International Space Station will be used to the greatest extent possible for exploration capability and technology development. Beyond this, NASA is evaluating a number of options for Proving Ground missions. An "Asteroid Redirect Mission" will demonstrate needed capabilities (e.g., Solar Electric Propulsion) and transportation systems for the crew (i.e., Space Launch System and Orion) and for cargo (i.e., Asteroid Redirect Vehicle). The Mars 2020 mission and follow-on robotic precursor missions will gather Mars surface environment information and will mature technologies. NASA is considering emplacing a small pressurized module in cis-lunar space to support crewed operations of increasing duration and to serve as a platform for critical exploration capabilities testing (e.g., radiation mitigation; extended duration deep space habitation). In addition, "opportunistic mission operations" could demonstrate capabilities not on the Mars critical path that may, nonetheless, enhance exploration operations (e.g., teleoperations, crew assisted Mars sample return). The Proving Ground may also include "pathfinder" missions to test and demonstrate specific capabilities at Mars (e.g., entry, descent, and landing). This paper describes the (1) process used to conduct an architecture-driven technology development assessment, (2) exploration mission critical and supporting capabilities, and (3) approach for addressing test and demonstration opportunities encompassing the spectrum of flight elements and destinations consistent with the Evolvable Mars Campaign.

Human Mars Landing Site and Impacts on Mars Surface Operations

Science.gov (United States)

Hoffman, Stephen J.; Bussey, Ben

2016-01-01

This paper describes NASA's initial steps for identifying and evaluating candidate Exploration Zones (EZs) and Regions of Interests (ROIs) for the first human crews that will explore the surface of Mars. NASA's current effort to define the exploration of this planet by human crews, known as the Evolvable Mars Campaign (EMC), provides the context in which these EZs and ROIs are being considered. The EMC spans all aspects of a human Mars mission including launch from Earth, transit to and from Mars, and operations on the surface of Mars. An EZ is a collection of ROIs located within approximately 100 kilometers of a centralized landing site. ROIs are areas relevant for scientific investigation and/or development/maturation of capabilities and resources necessary for a sustainable human presence. The EZ also contains one or more landing sites and a habitation site that will be used by multiple human crews during missions to explore and utilize the ROIs within the EZ. With the EMC as a conceptual basis, the EZ model has been refined to a point where specific site selection criteria for scientific exploration and in situ resource utilization can be defined. In 2015 these criteria were distributed to the planetary sciences community and the in situ resource utilization and civil engineering communities as part of a call for EZ proposals. The resulting "First Landing Site/Exploration Zone Workshop for Human Missions to the Surface of Mars" was held in October 2015 during which 47 proposals for EZs and ROIs were presented and discussed. Proposed locations spanned all longitudes and all allowable latitudes (+/- 50 degrees). Proposed justification for selecting one of these EZs also spanned a significant portion of the scientific and resource criteria provided to the community. Several important findings resulted from this Workshop including: (a) a strong consensus that, at a scale of 100 km (radius), multiple places on Mars exist that have both sufficient scientific interest

Mesoscale modeling of the water vapor cycle at Mawrth Vallis: a Mars2020 and ExoMars exploration rovers high-priority landing site

Science.gov (United States)

Pla-García, Jorge

2017-04-01

. During this transition, there is surface convergence into the rising branch (similar to the inter-tropical convergence zone on Earth), and dual Hadley cells with one circulation in each hemisphere. At this time, the mean surface winds flow from the high latitudes to equator in both hemispheres, providing the possibility for a direct vapor connection [5, 6]. It is likely that transient waves (e.g., storm systems) as well as boundary currents associated with planetary-scale stationary waves could advect and mix water equatorward, along the surface, in opposition to the Hadley Cell. Conclusion: We are studying whether moist air in northern spring/summer makes it to the surface of Mawrth at Ls 90, Ls 140 and Ls 180, three periods with high column abundance of water vapor at mid/high latitudes. The objective is to determine if the circulation (mean or regional) is favorable for the transport of water vapor from the north polar cap to MV where it might activate hygroscopic salts and/or chlorides [7]. Relative humidity at those different seasons is estimated to test for consistency with column abundances derived from orbit observations. If moist air makes it to MV during Ls90, 140 and/or 180, it should be a go-to site due to enhanced habitability implications. References: [1] Pla-García, J., & Rafkin, S. C., 2015: Meteorological predictions for Mars 2020 Exploration Rov-er high-priority landing sites throug MRAMS Mesoscale Modeling. In EGU General Assembly Conference Abstracts (Vol. 17, p. 12605). [2] Rafkin, S. C. R., Haberle, R. M., and T. I. Michaels, 2001: The Mars Regional Atmospheric Modeling System (MRAMS): Model description and selected simulations. Icarus, 151, 228-256. [3] Rafkin, S. C. R., M. R. V. Sta. Maria, and T. I. Michaels, 2002: Simulation of the atmospheric thermal circulation of a martian volcano using a mesoscale numerical model. Nature, 419, 697-699. [4] Jakosky, B.M., and C.B. Farmer, 1982: The seasonal and global behavior of water vapor in the Mars

Early Mars: A Warm Wet Niche for Life

Science.gov (United States)

Gibson, Everett K.; McKay, David S.; Thomas-Keprta, Kathie L.; Clemett, Simon J.

2010-01-01

Exploration of Mars has begun to unveil the history of the planet. Combinations of remote sensing, in situ compositional measurements and photographic observations have shown Mars had a dynamic and active geologic evolution. Mars geologic evolution had conditions that were suitable for supporting life. A habitable planet must have water, carbon and energy sources along with a dynamic geologic past. Mars meets all of these requirements. The first 600 Ma of Martian history were ripe for life to develop because of the abundance of: (i) Water-as shown by carved canyons and oceans or lakes with the early presence of near surface water shown by precipitated carbonates in ALH84001, well-dated at approx.3.9 Ga, (ii) Energy from the original accretional processes, a molten core which generated a strong magnetic field leaving a permanent record in the early crust, active volcanism continuing throughout Martian history, and continuing impact processes, (iii) Carbon, water and a likely thicker atmosphere from extensive volcanic outgassing (i.e. H2O, CO2, CH4, CO, O2, N2, H2S, SO2, etc.) and (iv) crustal tectonics as revealed by faulting and possible plate movement reflected by the magnetic patterns in the crust [1]. The question arises: "Why would life not develop from these favorable conditions on Mars in its first 600 Ma?" During this period, environmental near-surface conditions on Mars were more favorable to life than at any later time. Standing bodies of water, precipitation and flowing surface water, and possibly abundant hydrothermal energy would favor the formation of early life. (Even if life developed elsewhere on Earth, Venus, or on other bodies-it was transported to Mars where surface conditions were suitable for life to evolve)

Ultraviolet Testing of Space Suit Materials for Mars

Science.gov (United States)

Larson, Kristine; Fries, Marc

2017-01-01

Human missions to Mars may require radical changes in the approach to extra-vehicular (EVA) suit design. A major challenge is the balance of building a suit robust enough to complete multiple EVAs under intense ultraviolet (UV) light exposure without losing mechanical strength or compromising the suit's mobility. To study how the materials degrade on Mars in-situ, the Jet Propulsion Laboratory (JPL) invited the Advanced Space Suit team at NASA's Johnson Space Center (JSC) to place space suit materials on the Scanning Habitable Environments with Raman & Luminescence for Organics and Chemicals (SHERLOC) instrument's calibration target of the Mars 2020 rover. In order to select materials for the rover and understand the effects from Mars equivalent UV exposure, JSC conducted ground testing on both current and new space suit materials when exposed to 2500 hours of Mars mission equivalent UV. To complete this testing, JSC partnered with NASA's Marshall Space Flight Center to utilize their UV vacuum chambers. Materials tested were Orthofabric, polycarbonate, Teflon, Dacron, Vectran, spectra, bladder, nGimat coated Teflon, and nGimat coated Orthofabric. All samples were measured for mass, tensile strength, and chemical composition before and after radiation. Mass loss was insignificant (less than 0.5%) among the materials. Most materials loss tensile strength after radiation and became more brittle with a loss of elongation. Changes in chemical composition were seen in all radiated materials through Spectral Analysis. Results from this testing helped select the materials that will fly on the Mars 2020 rover. In addition, JSC can use this data to create a correlation to the chemical changes after radiation-which is what the rover will send back while on Mars-to the mechanical changes, such as tensile strength.

PAYING FOR PERFORMANCE: THE POWER OF INCENTIVES OVER HABITS

Science.gov (United States)

Sindelar, Jody L.

2010-01-01

New evidence suggests that individuals do not always make rational decisions, especially with regard to health habits. Smoking, misuse of alcohol, overeating and illicit drug use are leading causes of morbidity and mortality. Thus, influencing health habits is critical for improving overall health and well-being. This editorial argues that economists should take a more active role in shaping individuals’ health habits. Two recent innovations in economic theory pave the way. One change is that some economists now view rationality as bounded and willpower in short supply. Another, related to the first, is a more accepting perspective on paternalism, authorizing economists to help individuals make better choices when the neoclassical model breaks down. Findings from psychology offer incentive-based approaches; specifically, contingency management (CM). Economists could use this approach as a basis for developing public and private policies. PMID:18348117

Mars' Surface Radiation Environment Measured with the Mars Science Laboratory's Curiosity Rover

Science.gov (United States)

Hassler, Donald M.; Zeitlin, Cary; Wimmer-Schweingruber, Robert F.; Ehresmann, Bent; Rafkin, Scot; Eigenbrode, Jennifer L.; Brinza, David E.; Weigle, Gerald; Böttcher, Stephan; Böhm, Eckart; Burmeister, Soenke; Guo, Jingnan; Köhler, Jan; Martin, Cesar; Reitz, Guenther; Cucinotta, Francis A.; Kim, Myung-Hee; Grinspoon, David; Bullock, Mark A.; Posner, Arik; Gómez-Elvira, Javier; Vasavada, Ashwin; Grotzinger, John P.; MSL Science Team; Kemppinen, Osku; Cremers, David; Bell, James F.; Edgar, Lauren; Farmer, Jack; Godber, Austin; Wadhwa, Meenakshi; Wellington, Danika; McEwan, Ian; Newman, Claire; Richardson, Mark; Charpentier, Antoine; Peret, Laurent; King, Penelope; Blank, Jennifer; Schmidt, Mariek; Li, Shuai; Milliken, Ralph; Robertson, Kevin; Sun, Vivian; Baker, Michael; Edwards, Christopher; Ehlmann, Bethany; Farley, Kenneth; Griffes, Jennifer; Miller, Hayden; Newcombe, Megan; Pilorget, Cedric; Rice, Melissa; Siebach, Kirsten; Stack, Katie; Stolper, Edward; Brunet, Claude; Hipkin, Victoria; Léveillé, Richard; Marchand, Geneviève; Sánchez, Pablo Sobrón; Favot, Laurent; Cody, George; Steele, Andrew; Flückiger, Lorenzo; Lees, David; Nefian, Ara; Martin, Mildred; Gailhanou, Marc; Westall, Frances; Israël, Guy; Agard, Christophe; Baroukh, Julien; Donny, Christophe; Gaboriaud, Alain; Guillemot, Philippe; Lafaille, Vivian; Lorigny, Eric; Paillet, Alexis; Pérez, René; Saccoccio, Muriel; Yana, Charles; Armiens-Aparicio, Carlos; Rodríguez, Javier Caride; Blázquez, Isaías Carrasco; Gómez, Felipe Gómez; Hettrich, Sebastian; Malvitte, Alain Lepinette; Jiménez, Mercedes Marín; Martínez-Frías, Jesús; Martín-Soler, Javier; Martín-Torres, F. Javier; Jurado, Antonio Molina; Mora-Sotomayor, Luis; Caro, Guillermo Muñoz; López, Sara Navarro; Peinado-González, Verónica; Pla-García, Jorge; Manfredi, José Antonio Rodriguez; Romeral-Planelló, Julio José; Fuentes, Sara Alejandra Sans; Martinez, Eduardo Sebastian; Redondo, Josefina Torres; Urqui-O'Callaghan, Roser; Mier, María-Paz Zorzano; Chipera, Steve; Lacour, Jean-Luc; Mauchien, Patrick; Sirven, Jean-Baptiste; Manning, Heidi; Fairén, Alberto; Hayes, Alexander; Joseph, Jonathan; Squyres, Steven; Sullivan, Robert; Thomas, Peter; Dupont, Audrey; Lundberg, Angela; Melikechi, Noureddine; Mezzacappa, Alissa; Berger, Thomas; Matthia, Daniel; Prats, Benito; Atlaskin, Evgeny; Genzer, Maria; Harri, Ari-Matti; Haukka, Harri; Kahanpää, Henrik; Kauhanen, Janne; Kemppinen, Osku; Paton, Mark; Polkko, Jouni; Schmidt, Walter; Siili, Tero; Fabre, Cécile; Wray, James; Wilhelm, Mary Beth; Poitrasson, Franck; Patel, Kiran; Gorevan, Stephen; Indyk, Stephen; Paulsen, Gale; Gupta, Sanjeev; Bish, David; Schieber, Juergen; Gondet, Brigitte; Langevin, Yves; Geffroy, Claude; Baratoux, David; Berger, Gilles; Cros, Alain; d'Uston, Claude; Forni, Olivier; Gasnault, Olivier; Lasue, Jérémie; Lee, Qiu-Mei; Maurice, Sylvestre; Meslin, Pierre-Yves; Pallier, Etienne; Parot, Yann; Pinet, Patrick; Schröder, Susanne; Toplis, Mike; Lewin, Éric; Brunner, Will; Heydari, Ezat; Achilles, Cherie; Oehler, Dorothy; Sutter, Brad; Cabane, Michel; Coscia, David; Israël, Guy; Szopa, Cyril; Dromart, Gilles; Robert, François; Sautter, Violaine; Le Mouélic, Stéphane; Mangold, Nicolas; Nachon, Marion; Buch, Arnaud; Stalport, Fabien; Coll, Patrice; François, Pascaline; Raulin, François; Teinturier, Samuel; Cameron, James; Clegg, Sam; Cousin, Agnès; DeLapp, Dorothea; Dingler, Robert; Jackson, Ryan Steele; Johnstone, Stephen; Lanza, Nina; Little, Cynthia; Nelson, Tony; Wiens, Roger C.; Williams, Richard B.; Jones, Andrea; Kirkland, Laurel; Treiman, Allan; Baker, Burt; Cantor, Bruce; Caplinger, Michael; Davis, Scott; Duston, Brian; Edgett, Kenneth; Fay, Donald; Hardgrove, Craig; Harker, David; Herrera, Paul; Jensen, Elsa; Kennedy, Megan R.; Krezoski, Gillian; Krysak, Daniel; Lipkaman, Leslie; Malin, Michael; McCartney, Elaina; McNair, Sean; Nixon, Brian; Posiolova, Liliya; Ravine, Michael; Salamon, Andrew; Saper, Lee; Stoiber, Kevin; Supulver, Kimberley; Van Beek, Jason; Van Beek, Tessa; Zimdar, Robert; French, Katherine Louise; Iagnemma, Karl; Miller, Kristen; Summons, Roger; Goesmann, Fred; Goetz, Walter; Hviid, Stubbe; Johnson, Micah; Lefavor, Matthew; Lyness, Eric; Breves, Elly; Dyar, M. Darby; Fassett, Caleb; Blake, David F.; Bristow, Thomas; DesMarais, David; Edwards, Laurence; Haberle, Robert; Hoehler, Tori; Hollingsworth, Jeff; Kahre, Melinda; Keely, Leslie; McKay, Christopher; Wilhelm, Mary Beth; Bleacher, Lora; Brinckerhoff, William; Choi, David; Conrad, Pamela; Dworkin, Jason P.; Floyd, Melissa; Freissinet, Caroline; Garvin, James; Glavin, Daniel; Harpold, Daniel; Jones, Andrea; Mahaffy, Paul; Martin, David K.; McAdam, Amy; Pavlov, Alexander; Raaen, Eric; Smith, Michael D.; Stern, Jennifer; Tan, Florence; Trainer, Melissa; Meyer, Michael; Voytek, Mary; Anderson, Robert C.; Aubrey, Andrew; Beegle, Luther W.; Behar, Alberto; Blaney, Diana; Calef, Fred; Christensen, Lance; Crisp, Joy A.; DeFlores, Lauren; Ehlmann, Bethany; Feldman, Jason; Feldman, Sabrina; Flesch, Gregory; Hurowitz, Joel; Jun, Insoo; Keymeulen, Didier; Maki, Justin; Mischna, Michael; Morookian, John Michael; Parker, Timothy; Pavri, Betina; Schoppers, Marcel; Sengstacken, Aaron; Simmonds, John J.; Spanovich, Nicole; Juarez, Manuel de la Torre; Webster, Christopher R.; Yen, Albert; Archer, Paul Douglas; Jones, John H.; Ming, Douglas; Morris, Richard V.; Niles, Paul; Rampe, Elizabeth; Nolan, Thomas; Fisk, Martin; Radziemski, Leon; Barraclough, Bruce; Bender, Steve; Berman, Daniel; Dobrea, Eldar Noe; Tokar, Robert; Vaniman, David; Williams, Rebecca M. E.; Yingst, Aileen; Lewis, Kevin; Leshin, Laurie; Cleghorn, Timothy; Huntress, Wesley; Manhès, Gérard; Hudgins, Judy; Olson, Timothy; Stewart, Noel; Sarrazin, Philippe; Grant, John; Vicenzi, Edward; Wilson, Sharon A.; Hamilton, Victoria; Peterson, Joseph; Fedosov, Fedor; Golovin, Dmitry; Karpushkina, Natalya; Kozyrev, Alexander; Litvak, Maxim; Malakhov, Alexey; Mitrofanov, Igor; Mokrousov, Maxim; Nikiforov, Sergey; Prokhorov, Vasily; Sanin, Anton; Tretyakov, Vladislav; Varenikov, Alexey; Vostrukhin, Andrey; Kuzmin, Ruslan; Clark, Benton; Wolff, Michael; McLennan, Scott; Botta, Oliver; Drake, Darrell; Bean, Keri; Lemmon, Mark; Schwenzer, Susanne P.; Anderson, Ryan B.; Herkenhoff, Kenneth; Lee, Ella Mae; Sucharski, Robert; Hernández, Miguel Ángel de Pablo; Ávalos, Juan José Blanco; Ramos, Miguel; Malespin, Charles; Plante, Ianik; Muller, Jan-Peter; Navarro-González, Rafael; Ewing, Ryan; Boynton, William; Downs, Robert; Fitzgibbon, Mike; Harshman, Karl; Morrison, Shaunna; Dietrich, William; Kortmann, Onno; Palucis, Marisa; Sumner, Dawn Y.; Williams, Amy; Lugmair, Günter; Wilson, Michael A.; Rubin, David; Jakosky, Bruce; Balic-Zunic, Tonci; Frydenvang, Jens; Jensen, Jaqueline Kløvgaard; Kinch, Kjartan; Koefoed, Asmus; Madsen, Morten Bo; Stipp, Susan Louise Svane; Boyd, Nick; Campbell, John L.; Gellert, Ralf; Perrett, Glynis; Pradler, Irina; VanBommel, Scott; Jacob, Samantha; Owen, Tobias; Rowland, Scott; Atlaskin, Evgeny; Savijärvi, Hannu; García, César Martín; Mueller-Mellin, Reinhold; Bridges, John C.; McConnochie, Timothy; Benna, Mehdi; Franz, Heather; Bower, Hannah; Brunner, Anna; Blau, Hannah; Boucher, Thomas; Carmosino, Marco; Atreya, Sushil; Elliott, Harvey; Halleaux, Douglas; Rennó, Nilton; Wong, Michael; Pepin, Robert; Elliott, Beverley; Spray, John; Thompson, Lucy; Gordon, Suzanne; Newsom, Horton; Ollila, Ann; Williams, Joshua; Vasconcelos, Paulo; Bentz, Jennifer; Nealson, Kenneth; Popa, Radu; Kah, Linda C.; Moersch, Jeffrey; Tate, Christopher; Day, Mackenzie; Kocurek, Gary; Hallet, Bernard; Sletten, Ronald; Francis, Raymond; McCullough, Emily; Cloutis, Ed; ten Kate, Inge Loes; Kuzmin, Ruslan; Arvidson, Raymond; Fraeman, Abigail; Scholes, Daniel; Slavney, Susan; Stein, Thomas; Ward, Jennifer; Berger, Jeffrey; Moores, John E.

2014-01-01

The Radiation Assessment Detector (RAD) on the Mars Science Laboratory's Curiosity rover began making detailed measurements of the cosmic ray and energetic particle radiation environment on the surface of Mars on 7 August 2012. We report and discuss measurements of the absorbed dose and dose equivalent from galactic cosmic rays and solar energetic particles on the martian surface for ~300 days of observations during the current solar maximum. These measurements provide insight into the radiation hazards associated with a human mission to the surface of Mars and provide an anchor point with which to model the subsurface radiation environment, with implications for microbial survival times of any possible extant or past life, as well as for the preservation of potential organic biosignatures of the ancient martian environment.

Mars' surface radiation environment measured with the Mars Science Laboratory's Curiosity rover.

Science.gov (United States)

Hassler, Donald M; Zeitlin, Cary; Wimmer-Schweingruber, Robert F; Ehresmann, Bent; Rafkin, Scot; Eigenbrode, Jennifer L; Brinza, David E; Weigle, Gerald; Böttcher, Stephan; Böhm, Eckart; Burmeister, Soenke; Guo, Jingnan; Köhler, Jan; Martin, Cesar; Reitz, Guenther; Cucinotta, Francis A; Kim, Myung-Hee; Grinspoon, David; Bullock, Mark A; Posner, Arik; Gómez-Elvira, Javier; Vasavada, Ashwin; Grotzinger, John P

2014-01-24

The Radiation Assessment Detector (RAD) on the Mars Science Laboratory's Curiosity rover began making detailed measurements of the cosmic ray and energetic particle radiation environment on the surface of Mars on 7 August 2012. We report and discuss measurements of the absorbed dose and dose equivalent from galactic cosmic rays and solar energetic particles on the martian surface for ~300 days of observations during the current solar maximum. These measurements provide insight into the radiation hazards associated with a human mission to the surface of Mars and provide an anchor point with which to model the subsurface radiation environment, with implications for microbial survival times of any possible extant or past life, as well as for the preservation of potential organic biosignatures of the ancient martian environment.

Habits.

Science.gov (United States)

Robbins, T W; Costa, Rui M

2017-11-20

What is a habit? One problem with the concept of habit has been that virtually everyone has their own ideas of what is meant by such a term. Whilst not eschewing folk psychology, it is useful to re-examine dictionary definitions of 'habit'. The Oxford Dictionary of English defines habit as "a settled or regular tendency or practice, especially one that is hard to give up" and also "an automatic reaction to a specific situation". The latter, reassuringly, is not too far from what has come to be known as stimulus-response theory. Copyright © 2017 Elsevier Ltd. All rights reserved.

Challenges to Life on Mars --- Ecological Perspective

Science.gov (United States)

Sun, H.; McKay, C.; Friedmann, I.; McDonald, G.

2003-12-01

This talk will address the habitability of Mars by considering major environmental challenges against the tolerance limits of microorganisms from extreme terrestrial environments including the Antarctic desert and permafrost. At the planet surface, the combination of low atmospheric pressure (below the triple point of water), high fluxes of ultraviolet radiation, and one or more powerful oxidants are likely to create sterilizing conditions that will be a barrier to the colonization and dispersal of microorganisms. In the subsurface below, long-term survival is dependent upon the frequency and duration of warm, metabolically active periods that are needed to repair cellular damages. Low temperature itself does little harm to microorganisms, but a long dormant period will accrue lethal dosages of ionizing radiation and amino acid racemization. It is probable that within the depth range of current sampling technologies, there are no conditions for extant life, leaving organic or inorganic fossils as the only legitimate target in the search for life on Mars.

Photosynthesis within Mars' volcanic craters?: Insights from Cerro Negro Volcano, Nicaragua

Science.gov (United States)

Rogers, K. L.; Hynek, B. M.; McCollom, T. M.

2011-12-01

Discrete locales of sulfate-rich bedrocks exist on Mars and in many cases represent the products of acid-sulfate alteration of martian basalt. In some places, the products have been attributed to hydrothermal processes from local volcanism. In order to evaluate the habitability of such an environment, we are investigating the geochemical and biological composition of active fumaroles at Cerro Negro Volcano, Nicaragua, where fresh basaltic cinders similar in composition to martian basalts are altered by acidic, sulfur-bearing gases. Temperatures at active fumaroles can reach as high as 400°C and the pH of the steam ranges from Cyanobacteria and Ktedonobacteria, however Actinobacteria, alpha-Proteobacteria and Acidobacteria were also identified. Many of the cyanobacterial sequences were similar to those of the eukaryotic Cyanidiales, red algae that inhabit acidic, geothermal environments. Many of sequences related to Ktedonobacteria and Actinobacteria have also been found in acid mine drainage environments. The Archaeal community was far less diverse, with sequences matching those of unclassified Desulfurococcales and unclassified Thermoprotei. These sequences were more distant from isolated species than the bacterial sequences. Similar bacterial and archaeal communities have been found in hot spring environments in Yellowstone National Park, Greenland, Iceland, New Zealand and Costa Rica. Some of Mars' volcanoes were active for billions of years and by analogy to Cerro Negro, may have hosted photosynthetic organisms that could have been preserved in alteration mineral assemblages. Even on a generally cold and dry Mars, volcanic craters likely provided long-lived warm and wet conditions and should be a key target for future exploration assessing habitability.

"Some curious drawings". Mars through Giovanni Schiaparelli's eyes: between science and fiction.

Science.gov (United States)

Canadelli, Elena

2009-01-01

From the second half of the 19th century up to the first part of the 20th century the drawings of Mars by the Italian astronomer Giovanni Schiaparelli became the centre of an international controversy concerning the existence of canals and the hypothetical habitability of the red planet. These images also generated a full impact on the popular culture of the time. This essays follows the scientific representations of Mars by Schiaparelli (drawings of discs and maps) from their birth in the hands of the astronomy community up to their growing old in the hands of scientific popularizers such as Camille Flammarion and science fiction writers such as Herbert George Wells. With its seas and canyons Mars turned into the ideal background for scientific and exotic romanticism, offering a suitable setting for novels and tales. The core question crossed paths with the contemporary early 20th century debate raging on about the evolutionary theory. The study of Mars moved from astronomy to extraterrestrial physiology, biology, meteorology and geography: astronomical images then became imaginary portraits of Martians and artificial Martian landscapes.

Mars Atmosphere Resource Verification INsitu (MARVIN) - In Situ Resource Demonstration for the Mars 2020 Mission

Science.gov (United States)

Sanders, Gerald B.; Araghi, Koorosh; Ess, Kim M.; Valencia, Lisa M.; Muscatello, Anthony C.; Calle, Carlos I.; Clark, Larry; Iacomini, Christie

2014-01-01

The making of oxygen from resources in the Martian atmosphere, known as In Situ Resource Utilization (ISRU), has the potential to provide substantial benefits for future robotic and human exploration. In particular, the ability to produce oxygen on Mars for use in propulsion, life support, and power systems can provide significant mission benefits such as a reducing launch mass, lander size, and mission and crew risk. To advance ISRU for possible incorporation into future human missions to Mars, NASA proposed including an ISRU instrument on the Mars 2020 rover mission, through an announcement of opportunity (AO). The purpose of the the Mars Atmosphere Resource Verification INsitu or (MARVIN) instrument is to provide the first demonstration on Mars of oxygen production from acquired and stored Martian atmospheric carbon dioxide, as well as take measurements of atmospheric pressure and temperature, and of suspended dust particle sizes and amounts entrained in collected atmosphere gases at different times of the Mars day and year. The hardware performance and environmental data obtained will be critical for future ISRU systems that will reduce the mass of propellants and other consumables launched from Earth for robotic and human exploration, for better understanding of Mars dust and mitigation techniques to improve crew safety, and to help further define Mars global circulation models and better understand the regional atmospheric dynamics on Mars. The technologies selected for MARVIN are also scalable for future robotic sample return and human missions to Mars using ISRU.

Habit formation.

Science.gov (United States)

Smith, Kyle S; Graybiel, Ann M

2016-03-01

Habits, both good ones and bad ones, are pervasive in animal behavior. Important frameworks have been developed to understand habits through psychological and neurobiological studies. This work has given us a rich understanding of brain networks that promote habits, and has also helped us to understand what constitutes a habitual behavior as opposed to a behavior that is more flexible and prospective. Mounting evidence from studies using neural recording methods suggests that habit formation is not a simple process. We review this evidence and take the position that habits could be sculpted from multiple dissociable changes in neural activity. These changes occur across multiple brain regions and even within single brain regions. This strategy of classifying components of a habit based on different brain signals provides a potentially useful new way to conceive of disorders that involve overly fixed behaviors as arising from different potential dysfunctions within the brain's habit network.

A Mission Concept: Re-Entry Hopper-Aero-Space-Craft System on-Mars (REARM-Mars)

Science.gov (United States)

Davoodi, Faranak

2013-01-01

Future missions to Mars that would need a sophisticated lander, hopper, or rover could benefit from the REARM Architecture. The mission concept REARM Architecture is designed to provide unprecedented capabilities for future Mars exploration missions, including human exploration and possible sample-return missions, as a reusable lander, ascend/descend vehicle, refuelable hopper, multiple-location sample-return collector, laboratory, and a cargo system for assets and humans. These could all be possible by adding just a single customized Re-Entry-Hopper-Aero-Space-Craft System, called REARM-spacecraft, and a docking station at the Martian orbit, called REARM-dock. REARM could dramatically decrease the time and the expense required to launch new exploratory missions on Mars by making them less dependent on Earth and by reusing the assets already designed, built, and sent to Mars. REARM would introduce a new class of Mars exploration missions, which could explore much larger expanses of Mars in a much faster fashion and with much more sophisticated lab instruments. The proposed REARM architecture consists of the following subsystems: REARM-dock, REARM-spacecraft, sky-crane, secure-attached-compartment, sample-return container, agile rover, scalable orbital lab, and on-the-road robotic handymen.

A Habitable Fluvio-Lacustrine Environment at Yellowknife Bay, Gale Crater, Mars

Science.gov (United States)

Grotzinger, J. P.; Sumner, D. Y.; Kah, L. C.; Stack, K.; Gupta, S.; Edgar, L.; Rubin, D.; Lewis, K.; Schieber, J.; Mangold, N.; Milliken, R.; Conrad, P. G.; DesMarais, D.; Farmer, J.; Siebach, K.; Calef, F.; Hurowitz, J.; McLennan, S. M.; Ming, D.; Vaniman, D.; Crisp, J.; Vasavada, A.; Edgett, K. S.; Malin, M.; Blake, D.; Gellert, R.; Mahaffy, P.; Wiens, R. C.; Maurice, S.; Grant, J. A.; Wilson, S.; Anderson, R. C.; Beegle, L.; Arvidson, R.; Hallet, B.; Sletten, R. S.; Rice, M.; Bell, J.; Griffes, J.; Ehlmann, B.; Anderson, R. B.; Bristow, T. F.; Dietrich, W. E.; Dromart, G.; Eigenbrode, J.; Fraeman, A.; Hardgrove, C.; Herkenhoff, K.; Jandura, L.; Kocurek, G.; Lee, S.; Leshin, L. A.; Leveille, R.; Limonadi, D.; Maki, J.; McCloskey, S.; Meyer, M.; Minitti, M.; Newsom, H.; Oehler, D.; Okon, A.; Palucis, M.; Parker, T.; Rowland, S.; Schmidt, M.; Squyres, S.; Steele, A.; Stolper, E.; Summons, R.; Treiman, A.; Williams, R.; Yingst, A.; MSL Science Team; Kemppinen, Osku; Bridges, Nathan; Johnson, Jeffrey R.; Cremers, David; Godber, Austin; Wadhwa, Meenakshi; Wellington, Danika; McEwan, Ian; Newman, Claire; Richardson, Mark; Charpentier, Antoine; Peret, Laurent; King, Penelope; Blank, Jennifer; Weigle, Gerald; Li, Shuai; Robertson, Kevin; Sun, Vivian; Baker, Michael; Edwards, Christopher; Farley, Kenneth; Miller, Hayden; Newcombe, Megan; Pilorget, Cedric; Brunet, Claude; Hipkin, Victoria; Léveillé, Richard; Marchand, Geneviève; Sánchez, Pablo Sobrón; Favot, Laurent; Cody, George; Flückiger, Lorenzo; Lees, David; Nefian, Ara; Martin, Mildred; Gailhanou, Marc; Westall, Frances; Israël, Guy; Agard, Christophe; Baroukh, Julien; Donny, Christophe; Gaboriaud, Alain; Guillemot, Philippe; Lafaille, Vivian; Lorigny, Eric; Paillet, Alexis; Pérez, René; Saccoccio, Muriel; Yana, Charles; Armiens-Aparicio, Carlos; Rodríguez, Javier Caride; Blázquez, Isaías Carrasco; Gómez, Felipe Gómez; Gómez-Elvira, Javier; Hettrich, Sebastian; Malvitte, Alain Lepinette; Jiménez, Mercedes Marín; Martínez-Frías, Jesús; Martín-Soler, Javier; Martín-Torres, F. Javier; Jurado, Antonio Molina; Mora-Sotomayor, Luis; Caro, Guillermo Muñoz; López, Sara Navarro; Peinado-González, Verónica; Pla-García, Jorge; Manfredi, José Antonio Rodriguez; Romeral-Planelló, Julio José; Fuentes, Sara Alejandra Sans; Martinez, Eduardo Sebastian; Redondo, Josefina Torres; Urqui-O'Callaghan, Roser; Mier, María-Paz Zorzano; Chipera, Steve; Lacour, Jean-Luc; Mauchien, Patrick; Sirven, Jean-Baptiste; Manning, Heidi; Fairén, Alberto; Hayes, Alexander; Joseph, Jonathan; Sullivan, Robert; Thomas, Peter; Dupont, Audrey; Lundberg, Angela; Melikechi, Noureddine; Mezzacappa, Alissa; DeMarines, Julia; Grinspoon, David; Reitz, Günther; Prats, Benito; Atlaskin, Evgeny; Genzer, Maria; Harri, Ari-Matti; Haukka, Harri; Kahanpää, Henrik; Kauhanen, Janne; Paton, Mark; Polkko, Jouni; Schmidt, Walter; Siili, Tero; Fabre, Cécile; Wray, James; Wilhelm, Mary Beth; Poitrasson, Franck; Patel, Kiran; Gorevan, Stephen; Indyk, Stephen; Paulsen, Gale; Bish, David; Gondet, Brigitte; Langevin, Yves; Geffroy, Claude; Baratoux, David; Berger, Gilles; Cros, Alain; d'Uston, Claude; Forni, Olivier; Gasnault, Olivier; Lasue, Jérémie; Lee, Qiu-Mei; Meslin, Pierre-Yves; Pallier, Etienne; Parot, Yann; Pinet, Patrick; Schröder, Susanne; Toplis, Mike; Lewin, Éric; Brunner, Will; Heydari, Ezat; Achilles, Cherie; Sutter, Brad; Cabane, Michel; Coscia, David; Szopa, Cyril; Robert, François; Sautter, Violaine; Le Mouélic, Stéphane; Nachon, Marion; Buch, Arnaud; Stalport, Fabien; Coll, Patrice; François, Pascaline; Raulin, François; Teinturier, Samuel; Cameron, James; Clegg, Sam; Cousin, Agnès; DeLapp, Dorothea; Dingler, Robert; Jackson, Ryan Steele; Johnstone, Stephen; Lanza, Nina; Little, Cynthia; Nelson, Tony; Williams, Richard B.; Jones, Andrea; Kirkland, Laurel; Baker, Burt; Cantor, Bruce; Caplinger, Michael; Davis, Scott; Duston, Brian; Fay, Donald; Harker, David; Herrera, Paul; Jensen, Elsa; Kennedy, Megan R.; Krezoski, Gillian; Krysak, Daniel; Lipkaman, Leslie; McCartney, Elaina; McNair, Sean; Nixon, Brian; Posiolova, Liliya; Ravine, Michael; Salamon, Andrew; Saper, Lee; Stoiber, Kevin; Supulver, Kimberley; Van Beek, Jason; Van Beek, Tessa; Zimdar, Robert; French, Katherine Louise; Iagnemma, Karl; Miller, Kristen; Goesmann, Fred; Goetz, Walter; Hviid, Stubbe; Johnson, Micah; Lefavor, Matthew; Lyness, Eric; Breves, Elly; Dyar, M. Darby; Fassett, Caleb; Edwards, Laurence; Haberle, Robert; Hoehler, Tori; Hollingsworth, Jeff; Kahre, Melinda; Keely, Leslie; McKay, Christopher; Bleacher, Lora; Brinckerhoff, William; Choi, David; Dworkin, Jason P.; Floyd, Melissa; Freissinet, Caroline; Garvin, James; Glavin, Daniel; Harpold, Daniel; Martin, David K.; McAdam, Amy; Pavlov, Alexander; Raaen, Eric; Smith, Michael D.; Stern, Jennifer; Tan, Florence; Trainer, Melissa; Posner, Arik; Voytek, Mary; Aubrey, Andrew; Behar, Alberto; Blaney, Diana; Brinza, David; Christensen, Lance; DeFlores, Lauren; Feldman, Jason; Feldman, Sabrina; Flesch, Gregory; Jun, Insoo; Keymeulen, Didier; Mischna, Michael; Morookian, John Michael; Pavri, Betina; Schoppers, Marcel; Sengstacken, Aaron; Simmonds, John J.; Spanovich, Nicole; Juarez, Manuel de la Torre; Webster, Christopher R.; Yen, Albert; Archer, Paul Douglas; Cucinotta, Francis; Jones, John H.; Morris, Richard V.; Niles, Paul; Rampe, Elizabeth; Nolan, Thomas; Fisk, Martin; Radziemski, Leon; Barraclough, Bruce; Bender, Steve; Berman, Daniel; Dobrea, Eldar Noe; Tokar, Robert; Cleghorn, Timothy; Huntress, Wesley; Manhès, Gérard; Hudgins, Judy; Olson, Timothy; Stewart, Noel; Sarrazin, Philippe; Vicenzi, Edward; Bullock, Mark; Ehresmann, Bent; Hamilton, Victoria; Hassler, Donald; Peterson, Joseph; Rafkin, Scot; Zeitlin, Cary; Fedosov, Fedor; Golovin, Dmitry; Karpushkina, Natalya; Kozyrev, Alexander; Litvak, Maxim; Malakhov, Alexey; Mitrofanov, Igor; Mokrousov, Maxim; Nikiforov, Sergey; Prokhorov, Vasily; Sanin, Anton; Tretyakov, Vladislav; Varenikov, Alexey; Vostrukhin, Andrey; Kuzmin, Ruslan; Clark, Benton; Wolff, Michael; Botta, Oliver; Drake, Darrell; Bean, Keri; Lemmon, Mark; Schwenzer, Susanne P.; Lee, Ella Mae; Sucharski, Robert; Hernández, Miguel Ángel de Pablo; Ávalos, Juan José Blanco; Ramos, Miguel; Kim, Myung-Hee; Malespin, Charles; Plante, Ianik; Muller, Jan-Peter; Navarro-González, Rafael; Ewing, Ryan; Boynton, William; Downs, Robert; Fitzgibbon, Mike; Harshman, Karl; Morrison, Shaunna; Kortmann, Onno; Williams, Amy; Lugmair, Günter; Wilson, Michael A.; Jakosky, Bruce; Balic-Zunic, Tonci; Frydenvang, Jens; Jensen, Jaqueline Kløvgaard; Kinch, Kjartan; Koefoed, Asmus; Madsen, Morten Bo; Stipp, Susan Louise Svane; Boyd, Nick; Campbell, John L.; Perrett, Glynis; Pradler, Irina; VanBommel, Scott; Jacob, Samantha; Owen, Tobias; Savijärvi, Hannu; Boehm, Eckart; Böttcher, Stephan; Burmeister, Sönke; Guo, Jingnan; Köhler, Jan; García, César Martín; Mueller-Mellin, Reinhold; Wimmer-Schweingruber, Robert; Bridges, John C.; McConnochie, Timothy; Benna, Mehdi; Franz, Heather; Bower, Hannah; Brunner, Anna; Blau, Hannah; Boucher, Thomas; Carmosino, Marco; Atreya, Sushil; Elliott, Harvey; Halleaux, Douglas; Rennó, Nilton; Wong, Michael; Pepin, Robert; Elliott, Beverley; Spray, John; Thompson, Lucy; Gordon, Suzanne; Ollila, Ann; Williams, Joshua; Vasconcelos, Paulo; Bentz, Jennifer; Nealson, Kenneth; Popa, Radu; Moersch, Jeffrey; Tate, Christopher; Day, Mackenzie; Francis, Raymond; McCullough, Emily; Cloutis, Ed; ten Kate, Inge Loes; Scholes, Daniel; Slavney, Susan; Stein, Thomas; Ward, Jennifer; Berger, Jeffrey; Moores, John E.

2014-01-01

The Curiosity rover discovered fine-grained sedimentary rocks, which are inferred to represent an ancient lake and preserve evidence of an environment that would have been suited to support a martian biosphere founded on chemolithoautotrophy. This aqueous environment was characterized by neutral pH, low salinity, and variable redox states of both iron and sulfur species. Carbon, hydrogen, oxygen, sulfur, nitrogen, and phosphorus were measured directly as key biogenic elements; by inference, phosphorus is assumed to have been available. The environment probably had a minimum duration of hundreds to tens of thousands of years. These results highlight the biological viability of fluvial-lacustrine environments in the post-Noachian history of Mars.

Selection of the Mars Science Laboratory landing site

Science.gov (United States)

Golombek, M.; Grant, J.; Kipp, D.; Vasavada, A.; Kirk, Randolph L.; Fergason, Robin L.; Bellutta, P.; Calef, F.; Larsen, K.; Katayama, Y.; Huertas, A.; Beyer, R.; Chen, A.; Parker, T.; Pollard, B.; Lee, S.; Hoover, R.; Sladek, H.; Grotzinger, J.; Welch, R.; Dobrea, E. Noe; Michalski, J.; Watkins, M.

2012-01-01

The selection of Gale crater as the Mars Science Laboratory landing site took over five years, involved broad participation of the science community via five open workshops, and narrowed an initial >50 sites (25 by 20 km) to four finalists (Eberswalde, Gale, Holden and Mawrth) based on science and safety. Engineering constraints important to the selection included: (1) latitude (±30°) for thermal management of the rover and instruments, (2) elevation (surface that is safe for landing and roving and not dominated by fine-grained dust. Science criteria important for the selection include the ability to assess past habitable environments, which include diversity, context, and biosignature (including organics) preservation. Sites were evaluated in detail using targeted data from instruments on all active orbiters, and especially Mars Reconnaissance Orbiter. All of the final four sites have layered sedimentary rocks with spectral evidence for phyllosilicates that clearly address the science objectives of the mission. Sophisticated entry, descent and landing simulations that include detailed information on all of the engineering constraints indicate all of the final four sites are safe for landing. Evaluation of the traversabilty of the landing sites and target “go to” areas outside of the ellipse using slope and material properties information indicates that all are trafficable and “go to” sites can be accessed within the lifetime of the mission. In the final selection, Gale crater was favored over Eberswalde based on its greater diversity and potential habitability.

Mars Science Laboratory: Mission, Landing Site, and Initial Results

Science.gov (United States)

Grotzinger, John; Blake, D.; Crisp, J.; Edgett, K.; Gellert, R.; Gomez-Elvira, J.; Hassler, D.; Mahaffy, P.; Malin, M.; Meyer, M.; Mitrofanov, I.; Vasavada, A.; Wiens, R.

2012-10-01

Scheduled to land on August 5, 2012, the Mars Science Laboratory rover, Curiosity, will conduct an investigation of modern and ancient environments. Recent mission results will be discussed. Curiosity has a lifetime of at least one Mars year ( 23 months), and drive capability of at least 20 km. The MSL science payload was specifically assembled to assess habitability and includes a gas chromatograph-mass spectrometer and gas analyzer that will search for organic carbon in rocks, regolith fines, and the atmosphere; an x-ray diffractometer that will determine mineralogical diversity; focusable cameras that can image landscapes and rock/regolith textures in natural color; an alpha-particle x-ray spectrometer for in situ determination of rock and soil chemistry; a laser-induced breakdown spectrometer to remotely sense the chemical composition of rocks and minerals; an active neutron spectrometer designed to search for water in rocks/regolith; a weather station to measure modern-day environmental variables; and a sensor designed for continuous monitoring of background solar and cosmic radiation. The 155-km diameter Gale Crater was chosen as Curiosity’s field site based on several attributes: an interior mound of ancient flat-lying strata extending almost 5 km above the elevation of the landing site; the lower few hundred meters of the mound show a progression with relative age from clay-bearing to sulfate-bearing strata, separated by an unconformity from overlying likely anhydrous strata; the landing ellipse is characterized by a mixture of alluvial fan and high thermal inertia/high albedo stratified deposits; and a number of stratigraphically/geomorphically distinct fluvial features. Gale’s regional context and strong evidence for a progression through multiple potentially habitable environments, represented by a stratigraphic record of extraordinary extent, insure preservation of a rich record of the environmental history of early Mars.

The Icebreaker Mission to Search for Life on Mars

Science.gov (United States)

Stoker, C.; Mckay, C.; Brinckerhoff, W.; Davila, A.; Parro, V.; Quinn, R.

2015-01-01

The search for evidence of life on Mars is the ultimate motivation for its scientific exploration. The results from the Phoenix mission indicate that the high N. latitude ice-rich regolith at low elevations is likely to be a recently habitable place on Mars [Stoker et al., 2010]. The near-surface ice likely provided adequate water activity during periods of high obliquity, 3 to 10 Myr ago. Carbon dioxide and nitrogen are present in the atmosphere, and nitrates may be present in the soil. Together with iron in basaltic rocks and perchlorate in the soil they provide carbon and energy sources, and oxidative power to drive metabolism. Furthermore, the presence of organics is possible, as thermally reactive perchlorate would have prevented their detection by Viking and Phoenix. The Mars Icebreaker Life mission [McKay et al., 2013] focuses on the following science goals: (1) Search for biomolecular evidence of life; (2) Search for organic matter from either exogeneous or endogeneous sources using methods that are not effected by the presence of perchlorate; (3) Characterize oxidative species that produced reactivity of soils seen by Viking; and 4) Assess the habitability of the ice bearing soils. The Icebreaker Life payload (Figure 1) includes a 1-m rotary percussive drill that brings cuttings samples to the surface where they are delivered to three instruments (Fig. 1), the Signs of Life Detector (SOLID) [Parro et al., 2011] for biomolecular analysis, Laser Desorption Mass Spectrometer (LDMS) [??? 2015]) for broad spectrum organic analysis, and Wet Chemistry Laboratory (WCL) [Hecht et al., 2009] for detecting soluble species of nutrients and reactive oxidants. The Icebreaker payload fits on the Phoenix spacecraft and can land at the well-characterized Phoe-nix landing site in 2020 in a Discovery-class mission.

Landscapes of Mars A Visual Tour

CERN Document Server

Vogt, Gregory L

2008-01-01

Landscapes of Mars is essentially a picture book that provides a visual tour of Mars. All the major regions and topographical features will be shown and supplemented with chapter introductions and extended captions. In a way, think of it as a visual tourist guide. Other topics covered are Martian uplands on the order of the elevation of Mt. Everest, Giant volcanoes and a rift system, the Grand Canyon of Mars, craters and the absence of craters over large regions (erosion), and wind shadows around craters, sand dunes, and dust devils. The book includes discussions on the search for water (braided channels, seepage, sedimentary layering, etc.) as well as on the Viking mission search for life, Mars meteorite fossil bacteria controversy, and planetary protection in future missions. The book concludes with an exciting gallery of the best 3D images of Mars making the book a perfect tool for understanding Mars and its place in the solar system.

A Review of Habit Reversal with Childhood Habit Disorders.

Science.gov (United States)

Woods, Douglas W.; Miltenberger, Raymond G.

1996-01-01

This paper first reviews four classes of habit disorders in children: motor and vocal tics, nervous habits, stuttering, and Tourette's disorder. It then describes the habit reversal procedure and reviews the literature on its use and variations to treat each of the four classes of habit disorders. Emphasis is on simplified versions of the original…

Habit formation

Science.gov (United States)

Smith, Kyle S.; Graybiel, Ann M.

2016-01-01

Habits, both good ones and bad ones, are pervasive in animal behavior. Important frameworks have been developed to understand habits through psychological and neurobiological studies. This work has given us a rich understanding of brain networks that promote habits, and has also helped us to understand what constitutes a habitual behavior as opposed to a behavior that is more flexible and prospective. Mounting evidence from studies using neural recording methods suggests that habit formation is not a simple process. We review this evidence and take the position that habits could be sculpted from multiple dissociable changes in neural activity. These changes occur across multiple brain regions and even within single brain regions. This strategy of classifying components of a habit based on different brain signals provides a potentially useful new way to conceive of disorders that involve overly fixed behaviors as arising from different potential dysfunctions within the brain's habit network. PMID:27069378

Computer codes for evaluation of control room habitability (HABIT)

International Nuclear Information System (INIS)

Stage, S.A.

1996-06-01

This report describes the Computer Codes for Evaluation of Control Room Habitability (HABIT). HABIT is a package of computer codes designed to be used for the evaluation of control room habitability in the event of an accidental release of toxic chemicals or radioactive materials. Given information about the design of a nuclear power plant, a scenario for the release of toxic chemicals or radionuclides, and information about the air flows and protection systems of the control room, HABIT can be used to estimate the chemical exposure or radiological dose to control room personnel. HABIT is an integrated package of several programs that previously needed to be run separately and required considerable user intervention. This report discusses the theoretical basis and physical assumptions made by each of the modules in HABIT and gives detailed information about the data entry windows. Sample runs are given for each of the modules. A brief section of programming notes is included. A set of computer disks will accompany this report if the report is ordered from the Energy Science and Technology Software Center. The disks contain the files needed to run HABIT on a personal computer running DOS. Source codes for the various HABIT routines are on the disks. Also included are input and output files for three demonstration runs

Microbial Habitability in Gale Crater: Sample Analysis at Mars (SAM) Instrument Detection of Microbial Essential Carbon and Nitrogen

Science.gov (United States)

Sutter, B.; Ming, D. W.; Eigenbrode, J. E.; Steele, A.; Stern, J. C.; Gonzalez, R. N.; McAdam, A. C.; Mahaffy, P. R.

2016-01-01

Chemical analyses of Mars soils and sediments from previous landed missions have demonstrated that Mars surface materials possessed major (e.g., P, K, Ca, Mg, S) and minor (e.g., Fe, Mn, Zn, Ni, Cl) elements essential to support microbial life. However, the detection of microbial essential organic-carbon (C) and nitrate have been more elusive until the Mars Science Laboratory (MSL) rover mission. Nitrate and organic-C in Gale Crater, Mars have been detected by the Sample Analysis at Mars (SAM) instrument onboard the MSL Curiosity rover. Eolian fines and drilled sedimentary rock samples were heated in the SAM oven from approximately 30 to 860 degrees Centigrade where evolved gases (e.g., nitrous oxide (NO) and CO2) were released and analyzed by SAM’s quadrupole mass spectrometer (MS). The temperatures of evolved NO was assigned to nitrate while evolved CO2 was assigned to organic-C and carbonate. The CO2 releases in several samples occurred below 450 degrees Centigrade suggesting organic-C dominated in those samples. As much as 7 micromoles NO3-N per gram and 200 micromoles CO2-C per gram have been detected in the Gale Crater materials. These N and C levels coupled with assumed microbial biomass (9 x 10 (sup -7) micrograms per cell) C (0.5 micrograms C per micrograms cell) and N (0.14 micrograms N per micrograms cell) requirements, suggests that less than 1 percent and less than 10 percent of Gale Crater C and N, respectively, would be required if available, to accommodate biomass requirements of 1 by 10 (sup 5) cells per gram sediment. While nitrogen is the limiting nutrient, the potential exists that sufficient N and organic-C were present to support limited heterotrophic microbial populations that may have existed on ancient Mars.

Mars Science Laboratory Mission and Science Investigation

Science.gov (United States)

Grotzinger, John P.; Crisp, Joy; Vasavada, Ashwin R.; Anderson, Robert C.; Baker, Charles J.; Barry, Robert; Blake, David F.; Conrad, Pamela; Edgett, Kenneth S.; Ferdowski, Bobak; Gellert, Ralf; Gilbert, John B.; Golombek, Matt; Gómez-Elvira, Javier; Hassler, Donald M.; Jandura, Louise; Litvak, Maxim; Mahaffy, Paul; Maki, Justin; Meyer, Michael; Malin, Michael C.; Mitrofanov, Igor; Simmonds, John J.; Vaniman, David; Welch, Richard V.; Wiens, Roger C.

2012-09-01

Scheduled to land in August of 2012, the Mars Science Laboratory (MSL) Mission was initiated to explore the habitability of Mars. This includes both modern environments as well as ancient environments recorded by the stratigraphic rock record preserved at the Gale crater landing site. The Curiosity rover has a designed lifetime of at least one Mars year (˜23 months), and drive capability of at least 20 km. Curiosity's science payload was specifically assembled to assess habitability and includes a gas chromatograph-mass spectrometer and gas analyzer that will search for organic carbon in rocks, regolith fines, and the atmosphere (SAM instrument); an x-ray diffractometer that will determine mineralogical diversity (CheMin instrument); focusable cameras that can image landscapes and rock/regolith textures in natural color (MAHLI, MARDI, and Mastcam instruments); an alpha-particle x-ray spectrometer for in situ determination of rock and soil chemistry (APXS instrument); a laser-induced breakdown spectrometer to remotely sense the chemical composition of rocks and minerals (ChemCam instrument); an active neutron spectrometer designed to search for water in rocks/regolith (DAN instrument); a weather station to measure modern-day environmental variables (REMS instrument); and a sensor designed for continuous monitoring of background solar and cosmic radiation (RAD instrument). The various payload elements will work together to detect and study potential sampling targets with remote and in situ measurements; to acquire samples of rock, soil, and atmosphere and analyze them in onboard analytical instruments; and to observe the environment around the rover. The 155-km diameter Gale crater was chosen as Curiosity's field site based on several attributes: an interior mountain of ancient flat-lying strata extending almost 5 km above the elevation of the landing site; the lower few hundred meters of the mountain show a progression with relative age from clay-bearing to sulfate

Candidate cave entrances on Mars

Science.gov (United States)

Cushing, Glen E.

2012-01-01

This paper presents newly discovered candidate cave entrances into Martian near-surface lava tubes, volcano-tectonic fracture systems, and pit craters and describes their characteristics and exploration possibilities. These candidates are all collapse features that occur either intermittently along laterally continuous trench-like depressions or in the floors of sheer-walled atypical pit craters. As viewed from orbit, locations of most candidates are visibly consistent with known terrestrial features such as tube-fed lava flows, volcano-tectonic fractures, and pit craters, each of which forms by mechanisms that can produce caves. Although we cannot determine subsurface extents of the Martian features discussed here, some may continue unimpeded for many kilometers if terrestrial examples are indeed analogous. The features presented here were identified in images acquired by the Mars Odyssey's Thermal Emission Imaging System visible-wavelength camera, and by the Mars Reconnaissance Orbiter's Context Camera. Select candidates have since been targeted by the High-Resolution Imaging Science Experiment. Martian caves are promising potential sites for future human habitation and astrobiology investigations; understanding their characteristics is critical for long-term mission planning and for developing the necessary exploration technologies.

Space agriculture for habitation on Mars with hyper-thermophilic aerobic composting bacteria

Science.gov (United States)

Kanazawa, S.; Ishikawa, Y.; Tomita-Yokotani, K.; Hashimoto, H.; Kitaya, Y.; Yamashita, M.; Nagatomo, M.; Oshima, T.; Wada, H.; Space Agriculture Task Force, J.

Manned Mars exploration requires recycle of materials to support human life A conceptual design is developed for space agriculture which is driven by the biologically regenerative function Hyper-thermophilic aerobic composting bacterial ecology is the core of materials recycling system to process human metabolic waste and inedible biomass and convert them to fertilizer for plants cultivation A photosynthetic reaction of plants will be driven by solar energy Water will be recycled by cultivation of plants and passing it through plant bodies Sub-surface water and atmospheric carbon dioxide are the natural resource available on Mars and these resources will be converted to oxygen and foods We envision that the agricultural system will be scaled up by importing materials from Martian environment Excess oxygen will be obtained from growing trees for structural and other components Minor elements including N P K and other traces will be introduced as fertilizers or nutrients into the agricultural materials circulation Nitrogen will be collected from Martian atmosphere We will assess biological fixation of nitrogen using micro-organisms responsible in Earth biosphere Hyper-thermophilic aerobic bacterial ecology is effective to convert waste materials into useful forms to plants This microbial technology has been well established on ground for processing sewage and waste materials For instance the hyper-thermophilic bacterial system is applied to a composting machine in a size of a trash box in home kitchen Since such a home electronics

Science in Exploration: From the Moon to Mars and Back Home to Earth

Science.gov (United States)

Garvin, James B.

2007-01-01

NASA is embarking on a grand journey of exploration that naturally integrates the past successes of the Apollo missions to the Moon, as well as robotic science missions to Mars, to Planet Earth, and to the broader Universe. The US Vision for Space Exporation (VSE) boldly lays out a plan for human and robotic reconnaissance of the accessible Universe, starting with the surface of the Moon, and later embracing the surface of Mars. Sustained human and robotic access to the Moon and Mars will enable a new era of scientific investigation of our planetary neighbors, tied to driving scientific questions that pertain to the evolution and destiny of our home planet, but which also can be related to the search habitable worlds across the nearby Universe. The Apollo missions provide a vital legacy for what can be learned from the Moon, and NASA is now poised to recapture the lunar frontier starting with the flight of the Lunar Reconnaissance Orbiter (LRO) in late 2008. LRO will provide a new scientific context from which joint human and robotic exploration will ensue, guided by objectives some of which are focused on the grandest scientific challenges imaginable : Where did we come from? Are we alone? and Where are we going? The Moon will serve as an essential stepping stone for sustained human access and exploration of deep space and as a training ground while robotic missions with ever increasing complexity probe the wonders of Mars. As we speak, an armada of spacecraft are actively investigating the red planet both from orbit (NASA's Mars Reconnaissance Orbiter and Mars Odyssey Orbiter, plus ESA's Mars Express) and from the surface (NASA's twin Mars Exploration Rovers, and in 2008 NASA's Phoenix polar lander). The dramatically changing views of Mars as a potentially habitable world, with its own flavor of global climate change and unique climate records, provides a new vantage point from which to observe and question the workings of our own planet Earth. By 2010 NASA will

A two-tiered approach to assessing the habitability of exoplanets.

Science.gov (United States)

Schulze-Makuch, Dirk; Méndez, Abel; Fairén, Alberto G; von Paris, Philip; Turse, Carol; Boyer, Grayson; Davila, Alfonso F; António, Marina Resendes de Sousa; Catling, David; Irwin, Louis N

2011-12-01

In the next few years, the number of catalogued exoplanets will be counted in the thousands. This will vastly expand the number of potentially habitable worlds and lead to a systematic assessment of their astrobiological potential. Here, we suggest a two-tiered classification scheme of exoplanet habitability. The first tier consists of an Earth Similarity Index (ESI), which allows worlds to be screened with regard to their similarity to Earth, the only known inhabited planet at this time. The ESI is based on data available or potentially available for most exoplanets such as mass, radius, and temperature. For the second tier of the classification scheme we propose a Planetary Habitability Index (PHI) based on the presence of a stable substrate, available energy, appropriate chemistry, and the potential for holding a liquid solvent. The PHI has been designed to minimize the biased search for life as we know it and to take into account life that might exist under more exotic conditions. As such, the PHI requires more detailed knowledge than is available for any exoplanet at this time. However, future missions such as the Terrestrial Planet Finder will collect this information and advance the PHI. Both indices are formulated in a way that enables their values to be updated as technology and our knowledge about habitable planets, moons, and life advances. Applying the proposed metrics to bodies within our Solar System for comparison reveals two planets in the Gliese 581 system, GJ 581 c and d, with an ESI comparable to that of Mars and a PHI between that of Europa and Enceladus.

The Icebreaker Life Mission to Mars: A Search for Biomolecular Evidence for Life

Science.gov (United States)

Mckay, Christopher P.; Stoker, Carol R.; Glass, Brian J.; Dave, Arwen I.; Davila, Alfonso F.; Heldmann, Jennifer L.; Marinova, Margarita M.; Fairen, Alberto G; Quinn, Richard C; Zacny, Kris A.;

Quantitative habitability.

Science.gov (United States)

Shock, Everett L; Holland, Melanie E

2007-12-01

A framework is proposed for a quantitative approach to studying habitability. Considerations of environmental supply and organismal demand of energy lead to the conclusions that power units are most appropriate and that the units for habitability become watts per organism. Extreme and plush environments are revealed to be on a habitability continuum, and extreme environments can be quantified as those where power supply only barely exceeds demand. Strategies for laboratory and field experiments are outlined that would quantify power supplies, power demands, and habitability. An example involving a comparison of various metabolisms pursued by halophiles is shown to be well on the way to a quantitative habitability analysis.

Some Ecological Mechanisms to Generate Habitability in Planetary Subsurface Areas by Chemolithotrophic Communities: The Ro Tinto Subsurface Ecosystem as a Model System

Science.gov (United States)

Fernández-Remolar, David C.; Gómez, Felipe; Prieto-Ballesteros, Olga; Schelble, Rachel T.; Rodríguez, Nuria; Amiols, Ricardo

2008-02-01

Chemolithotrophic communities that colonize subsurface habitats have great relevance for the astrobiological exploration of our Solar System. We hypothesize that the chemical and thermal stabilization of an environment through microbial activity could make a given planetary region habitable. The MARTE project ground-truth drilling campaigns that sampled cryptic subsurface microbial communities in the basement of the Ro Tinto headwaters have shown that acidic surficial habitats are the result of the microbial oxidation of pyritic ores. The oxidation process is exothermic and releases heat under both aerobic and anaerobic conditions. These microbial communities can maintain the subsurface habitat temperature through storage heat if the subsurface temperature does not exceed their maximum growth temperature. In the acidic solutions of the Ro Tinto, ferric iron acts as an effective buffer for controlling water pH. Under anaerobic conditions, ferric iron is the oxidant used by microbes to decompose pyrite through the production of sulfate, ferrous iron, and protons. The integration between the physical and chemical processes mediated by microorganisms with those driven by the local geology and hydrology have led us to hypothesize that thermal and chemical regulation mechanisms exist in this environment and that these homeostatic mechanisms could play an essential role in creating habitable areas for other types of microorganisms. Therefore, searching for the physicochemical expression of extinct and extant homeostatic mechanisms through physical and chemical anomalies in the Mars crust (i.e., local thermal gradient or high concentration of unusual products such as ferric sulfates precipitated out from acidic solutions produced by hypothetical microbial communities) could be a first step in the search for biological traces of a putative extant or extinct Mars biosphere.

Land of Addicts? An Empirical Investigation of Habit-Based Asset Pricing Models

OpenAIRE

Sydney Ludvigson; Xiaohong Chen

2004-01-01

A leading explanation of aggregate stock market behavior suggests that assets are priced as if there were a representative investor whose utility is a power function of the difference between aggregate consumption and a "habit" level, where the habit is some function of lagged and (possibly) contemporaneous consumption. But theory does not provide precise guidelines about the parametric functional relationship between the habit and aggregate consumption. This makes formal estimation and testi...

On the Habitability of Desert Varnish: A Combined Study by Micro-Raman Spectroscopy, X-ray Diffraction, and Methylated Pyrolysis-Gas Chromatography-Mass Spectrometry.

Science.gov (United States)

Malherbe, C; Hutchinson, I B; Ingley, R; Boom, A; Carr, A S; Edwards, H; Vertruyen, B; Gilbert, B; Eppe, G

2017-11-01

In 2020, the ESA ExoMars and NASA Mars 2020 missions will be launched to Mars to search for evidence of past and present life. In preparation for these missions, terrestrial analog samples of rock formations on Mars are studied in detail in order to optimize the scientific information that the analytical instrumentation will return. Desert varnishes are thin mineral coatings found on rocks in arid and semi-arid environments on Earth that are recognized as analog samples. During the formation of desert varnishes (which takes many hundreds of years), organic matter is incorporated, and microorganisms may also play an active role in the formation process. During this study, four complementary analytical techniques proposed for Mars missions (X-ray diffraction [XRD], Raman spectroscopy, elemental analysis, and pyrolysis-gas chromatography-mass spectrometry [Py-GC-MS]) were used to interrogate samples of desert varnish and describe their capacity to sustain life under extreme scenarios. For the first time, both the geochemistry and the organic compounds associated with desert varnish are described with the use of identical sets of samples. XRD and Raman spectroscopy measurements were used to nondestructively interrogate the mineralogy of the samples. In addition, the use of Raman spectroscopy instruments enabled the detection of β-carotene, a highly Raman-active biomarker. The content and the nature of the organic material in the samples were further investigated with elemental analysis and methylated Py-GC-MS, and a bacterial origin was determined to be likely. In the context of planetary exploration, we describe the habitable nature of desert varnish based on the biogeochemical composition of the samples. Possible interference of the geological substrate on the detectability of pyrolysis products is also suggested. Key Words: Desert varnish-Habitability-Raman spectroscopy-Py-GC-MS-XRD-ExoMars-Planetary science. Astrobiology 17, 1123-1137.

Low Biotoxicity of Mars Analog Soils Suggests that the Surface of Mars May be Habitable for Terrestrial Microorganisms

Science.gov (United States)

Schuerger, A. C.; Ming, Douglas W.; Golden, D. C.

2012-01-01

Recent studies on the interactive effects of hypobaria, low temperatures, and CO2-enriched anoxic atmospheres on the growth of 37 species of mesophilic bacteria identified 14 potential biocidal agents that might affect microbial survival and growth on the martian surface. Biocidal or inhibitory factors include (not in priority): (1) solar UV irradiation, (2) low pressure, (3) extreme desiccating conditions, (4) extreme diurnal temperature fluctuations, (5) solar particle events, (6) galactic cosmic rays, (7) UV-glow discharge from blowing dust, (8) solar UV-induced volatile oxidants [e.g., O2(-), O(-), H2O2, O3], (9) globally distributed oxidizing soils, (10) extremely high salts levels [e.g., MgCl2, NaCl, FeSO4, and MgSO4] in surficial soils at some sites on Mars, (11) high concentrations of heavy metals in martian soils, (12) likely acidic conditions in martian fines, (13) high CO2 concentrations in the global atmosphere, and (14) perchlorate-rich soils. Despite these extreme conditions several studies have demonstrated that dormant spores or vegetative cells of terrestrial microorganisms can survive simulated martian conditions as long as they are protected from UV irradiation. What has not been explored in depth are the effects of potential biotoxic geochemical components of the martian regolith on the survival and growth of microorganisms. The primary objectives of the research included: (1) prepare and characterize Mars analog soils amended with potential biotoxic levels of sulfates, salts, acidifying minerals, etc.; and (2) use the simulants to conduct biotoxicity assays to determine if terrestrial microorganisms from spacecraft can survive direct exposure to the analog soils.

CONSTRAINING THE RADIATION AND PLASMA ENVIRONMENT OF THE KEPLER CIRCUMBINARY HABITABLE-ZONE PLANETS

Energy Technology Data Exchange (ETDEWEB)

Zuluaga, Jorge I. [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States); Mason, Paul A. [New Mexico State University—DACC, Las Cruces, NM 88003 (United States); Cuartas-Restrepo, Pablo A. [FACom—Instituto de Física—FCEN, Universidad de Antioquia, Calle 70 No. 52-21, Medellín (Colombia)

2016-02-20

The discovery of many planets using the Kepler telescope includes 10 planets orbiting eight binary stars. Three binaries, Kepler-16, Kepler-47, and Kepler-453, have at least one planet in the circumbinary habitable zone (BHZ). We constrain the level of high-energy radiation and the plasma environment in the BHZ of these systems. With this aim, BHZ limits in these Kepler binaries are calculated as a function of time, and the habitability lifetimes are estimated for hypothetical terrestrial planets and/or moons within the BHZ. With the time-dependent BHZ limits established, a self-consistent model is developed describing the evolution of stellar activity and radiation properties as proxies for stellar aggression toward planetary atmospheres. Modeling binary stellar rotation evolution, including the effect of tidal interaction between stars in binaries, is key to establishing the environment around these systems. We find that Kepler-16 and its binary analogs provide a plasma environment favorable for the survival of atmospheres of putative Mars-sized planets and exomoons. Tides have modified the rotation of the stars in Kepler-47, making its radiation environment less harsh in comparison to the solar system. This is a good example of the mechanism first proposed by Mason et al. Kepler-453 has an environment similar to that of the solar system with slightly better than Earth radiation conditions at the inner edge of the BHZ. These results can be reproduced and even reparameterized as stellar evolution and binary tidal models progress, using our online tool http://bhmcalc.net.

CONSTRAINING THE RADIATION AND PLASMA ENVIRONMENT OF THE KEPLER CIRCUMBINARY HABITABLE-ZONE PLANETS

International Nuclear Information System (INIS)

Zuluaga, Jorge I.; Mason, Paul A.; Cuartas-Restrepo, Pablo A.

2016-01-01

The discovery of many planets using the Kepler telescope includes 10 planets orbiting eight binary stars. Three binaries, Kepler-16, Kepler-47, and Kepler-453, have at least one planet in the circumbinary habitable zone (BHZ). We constrain the level of high-energy radiation and the plasma environment in the BHZ of these systems. With this aim, BHZ limits in these Kepler binaries are calculated as a function of time, and the habitability lifetimes are estimated for hypothetical terrestrial planets and/or moons within the BHZ. With the time-dependent BHZ limits established, a self-consistent model is developed describing the evolution of stellar activity and radiation properties as proxies for stellar aggression toward planetary atmospheres. Modeling binary stellar rotation evolution, including the effect of tidal interaction between stars in binaries, is key to establishing the environment around these systems. We find that Kepler-16 and its binary analogs provide a plasma environment favorable for the survival of atmospheres of putative Mars-sized planets and exomoons. Tides have modified the rotation of the stars in Kepler-47, making its radiation environment less harsh in comparison to the solar system. This is a good example of the mechanism first proposed by Mason et al. Kepler-453 has an environment similar to that of the solar system with slightly better than Earth radiation conditions at the inner edge of the BHZ. These results can be reproduced and even reparameterized as stellar evolution and binary tidal models progress, using our online tool http://bhmcalc.net

In situ detection of boron by ChemCam on Mars

Science.gov (United States)

Gasda, Patrick J.; Haldeman, Ethan B.; Wiens, Roger C.; Rapin, William; Bristow, Thomas F.; Bridges, John C.; Schwenzer, Susanne P.; Clark, Benton; Herkenhoff, Kenneth; Frydenvang, Jens; Lanza, Nina L.; Maurice, Sylvestre; Clegg, Samuel; Delapp, Dorothea M.; Sanford, Veronica L.; Bodine, Madeleine R.; McInroy, Rhonda

2017-09-01

We report the first in situ detection of boron on Mars. Boron has been detected in Gale crater at levels Curiosity rover ChemCam instrument in calcium-sulfate-filled fractures, which formed in a late-stage groundwater circulating mainly in phyllosilicate-rich bedrock interpreted as lacustrine in origin. We consider two main groundwater-driven hypotheses to explain the presence of boron in the veins: leaching of borates out of bedrock or the redistribution of borate by dissolution of borate-bearing evaporite deposits. Our results suggest that an evaporation mechanism is most likely, implying that Gale groundwaters were mildly alkaline. On Earth, boron may be a necessary component for the origin of life; on Mars, its presence suggests that subsurface groundwater conditions could have supported prebiotic chemical reactions if organics were also present and provides additional support for the past habitability of Gale crater.

Silicates Eroded under Simulated Martian Conditions Effectively Kill Bacteria-A Challenge for Life on Mars.

Science.gov (United States)

Bak, Ebbe N; Larsen, Michael G; Moeller, Ralf; Nissen, Silas B; Jensen, Lasse R; Nørnberg, Per; Jensen, Svend J K; Finster, Kai

2017-01-01

The habitability of Mars is determined by the physical and chemical environment. The effect of low water availability, temperature, low atmospheric pressure and strong UV radiation has been extensively studied in relation to the survival of microorganisms. In addition to these stress factors, it was recently found that silicates exposed to simulated saltation in a Mars-like atmosphere can lead to a production of reactive oxygen species. Here, we have investigated the stress effect induced by quartz and basalt abraded in Mars-like atmospheres by examining the survivability of the three microbial model organisms Pseudomonas putida, Bacillus subtilis , and Deinococcus radiodurans upon exposure to the abraded silicates. We found that abraded basalt that had not been in contact with oxygen after abrasion killed more than 99% of the vegetative cells while endospores were largely unaffected. Exposure of the basalt samples to oxygen after abrasion led to a significant reduction in the stress effect. Abraded quartz was generally less toxic than abraded basalt. We suggest that the stress effect of abraded silicates may be caused by a production of reactive oxygen species and enhanced by transition metal ions in the basalt leading to hydroxyl radicals through Fenton-like reactions. The low survivability of the usually highly resistant D. radiodurans indicates that the effect of abraded silicates, as is ubiquitous on the Martian surface, would limit the habitability of Mars as well as the risk of forward contamination. Furthermore, the reactivity of abraded silicates could have implications for future manned missions, although the lower effect of abraded silicates exposed to oxygen suggests that the effects would be reduced in human habitats.

Silicates Eroded under Simulated Martian Conditions Effectively Kill Bacteria—A Challenge for Life on Mars

Directory of Open Access Journals (Sweden)

Ebbe N. Bak

2017-09-01

Full Text Available The habitability of Mars is determined by the physical and chemical environment. The effect of low water availability, temperature, low atmospheric pressure and strong UV radiation has been extensively studied in relation to the survival of microorganisms. In addition to these stress factors, it was recently found that silicates exposed to simulated saltation in a Mars-like atmosphere can lead to a production of reactive oxygen species. Here, we have investigated the stress effect induced by quartz and basalt abraded in Mars-like atmospheres by examining the survivability of the three microbial model organisms Pseudomonas putida, Bacillus subtilis, and Deinococcus radiodurans upon exposure to the abraded silicates. We found that abraded basalt that had not been in contact with oxygen after abrasion killed more than 99% of the vegetative cells while endospores were largely unaffected. Exposure of the basalt samples to oxygen after abrasion led to a significant reduction in the stress effect. Abraded quartz was generally less toxic than abraded basalt. We suggest that the stress effect of abraded silicates may be caused by a production of reactive oxygen species and enhanced by transition metal ions in the basalt leading to hydroxyl radicals through Fenton-like reactions. The low survivability of the usually highly resistant D. radiodurans indicates that the effect of abraded silicates, as is ubiquitous on the Martian surface, would limit the habitability of Mars as well as the risk of forward contamination. Furthermore, the reactivity of abraded silicates could have implications for future manned missions, although the lower effect of abraded silicates exposed to oxygen suggests that the effects would be reduced in human habitats.

Flashline Mars Arctic Research Station (FMARS) 2009 Expedition Crew Perspectives

Science.gov (United States)

Cusack, Stacy; Ferrone, Kristine; Garvin, Christy; Kramer, W. Vernon; Palaia, Joseph, IV; Shiro, Brian

2009-01-01

The Flashline Mars Arctic Research Station (FMARS), located on the rim of the Haughton Crater on Devon Island in the Canadian Arctic, is a simulated Mars habitat that provides operational constraints similar to those which will be faced by future human explorers on Mars. In July 2009, a six-member crew inhabited the isolated habitation module and conducted the twelfth FMARS mission. The crew members conducted frequent EVA operations wearing mock space suits to conduct field experiments under realistic Mars-like conditions. Their scientific campaign spanned a wide range of disciplines and included many firsts for Mars analog research. Among these are the first use of a Class IV medical laser during a Mars simulation, helping to relieve crew stress injuries during the mission. Also employed for the first time in a Mars simulation at FMARS, a UAV (Unmanned Aerial Vehicle) was used by the space-suited explorers, aiding them in their search for mineral resources. Sites identified by the UAV were then visited by geologists who conducted physical geologic sampling. For the first time, explorers in spacesuits deployed passive seismic equipment to monitor earthquake activity and characterize the planet's interior. They also conducted the first geophysical electromagnetic survey as analog Mars pioneers to search for water and characterize geological features under the surface. The crew collected hydrated minerals and attempted to produce drinkable water from the rocks. A variety of equipment was field tested as well, including new cameras that automatically geotag photos, data-recording GPS units, a tele-presence rover (operated from Florida), as well as MIT-developed mission planning software. As plans develop to return to the Moon and go on to Mars, analog facilities like FMARS can provide significant benefit to NASA and other organizations as they prepare for robust human space exploration. The authors will present preliminary results from these studies as well as their

Habitability: A Review.

Science.gov (United States)

Cockell, C S; Bush, T; Bryce, C; Direito, S; Fox-Powell, M; Harrison, J P; Lammer, H; Landenmark, H; Martin-Torres, J; Nicholson, N; Noack, L; O'Malley-James, J; Payler, S J; Rushby, A; Samuels, T; Schwendner, P; Wadsworth, J; Zorzano, M P

2016-01-01

Habitability is a widely used word in the geoscience, planetary science, and astrobiology literature, but what does it mean? In this review on habitability, we define it as the ability of an environment to support the activity of at least one known organism. We adopt a binary definition of "habitability" and a "habitable environment." An environment either can or cannot sustain a given organism. However, environments such as entire planets might be capable of supporting more or less species diversity or biomass compared with that of Earth. A clarity in understanding habitability can be obtained by defining instantaneous habitability as the conditions at any given time in a given environment required to sustain the activity of at least one known organism, and continuous planetary habitability as the capacity of a planetary body to sustain habitable conditions on some areas of its surface or within its interior over geological timescales. We also distinguish between surface liquid water worlds (such as Earth) that can sustain liquid water on their surfaces and interior liquid water worlds, such as icy moons and terrestrial-type rocky planets with liquid water only in their interiors. This distinction is important since, while the former can potentially sustain habitable conditions for oxygenic photosynthesis that leads to the rise of atmospheric oxygen and potentially complex multicellularity and intelligence over geological timescales, the latter are unlikely to. Habitable environments do not need to contain life. Although the decoupling of habitability and the presence of life may be rare on Earth, it may be important for understanding the habitability of other planetary bodies.

The key to Mars, Titan and beyond?

International Nuclear Information System (INIS)

Zubrin, R.M.

1990-01-01

This paper discusses the use of nuclear rockets using indigenous Mars propellants for future missions to Mars and Titan, which would drastically reduce the mass and cost of the mission while increasing its capability. Special attention is given to the CO2-powered nuclear rocket using indigenous Martian fuel (NIMF) vehicle for hopping around on Mars. If water is available on Mars, it could make a NIMF propellant yielding an exhaust velocity of 3.4 km/sec, good enough to allow a piloted NIMF spacecraft to ascent from the surface of Mars and propel itself directly to LEO; if water is available on Phobos, a NIMF spacecraft could travel to earth orbit and then back to Phobos or Mars without any additional propellant from earth. One of the many exciting missions beyond Mars that will be made possible by NIMF technology is the exploration of Saturn's moon Titan. A small automated NIMF Titan explorer, with foldout wings and a NERVA (Nuclear Engine for Rocket Vehicle Applications) engine, is proposed

Astrobiological aspects of Mars and human presence: pros and cons.

Science.gov (United States)

Horneck, G

2008-08-01

After the realization of the International Space Station, human exploratory missions to Moon or Mars, i.e. beyond low Earth orbit, are widely considered as the next logical step of peaceful cooperation in space on a global scale. Besides the human desire to extend the window of habitability, human exploratory missions are driven by several aspects of science, technology, culture and economy. Mars is currently considered as a major target in the search for life beyond the Earth. Understanding the history of water on Mars appears to be one of the clues to the puzzle on the probability of life on Mars. On Earth microorganisms have flourished for more than 3.5 Ga and have developed strategies to cope with so-called extreme conditions (e.g., hot vents, permafrost, subsurface regions, rocks or salt crystals). Therefore, in search for life on Mars, microorganisms are the most likely candidates for a putative biota on Mars and the search for morphological or chemical signatures of life or its relics is one of the primary and most exciting goals of Mars exploration. The presence of humans on the surface of Mars will substantially increase this research potential, e.g., by supporting deep subsurface drilling and by allowing intellectual collection and sophisticated in situ analysis of samples of astrobiological interest. On the other hand, such long-duration missions beyond LEO will add a new dimension to human space flight, concerning the distance of travel, the radiation environment, the gravity levels, the duration of the mission, and the level of confinement and isolation the crew will be exposed to. This will raise the significance of several health issues, above all radiation protection, gravity related effects as well as psychological issues. Furthermore, the import of internal and external microorganisms inevitably accompanying any human mission to Mars, or brought purposely to Mars as part of a bioregenerative life support system needs careful consideration with

Potential Applications of Modularity to Enable a Deep Space Habitation Capability for Future Human Exploration Beyond Low-Earth Orbit

Science.gov (United States)

Simon, Matthew A.; Toups, Larry; Smitherman, David

2012-01-01

Evaluating preliminary concepts of a Deep Space Habitat (DSH) enabling long duration crewed exploration of asteroids, the Moon, and Mars is a technically challenging problem. Sufficient habitat volumes and equipment, necessary to ensure crew health and functionality, increase propellant requirements and decrease launch flexibility to deliver multiple elements on a single launch vehicle; both of which increase overall mission cost. Applying modularity in the design of the habitat structures and subsystems can alleviate these difficulties by spreading the build-up of the overall habitation capability across several smaller parts. This allows for a more flexible habitation approach that accommodates various crew mission durations and levels of functionality. This paper provides a technical analysis of how various modular habitation approaches can impact the parametric design of a DSH with potential benefits in mass, packaging volume, and architectural flexibility. This includes a description of the desired long duration habitation capability, the definition of a baseline model for comparison, a small trade study to investigate alternatives, and commentary on potentially advantageous configurations to enable different levels of habitability. The approaches investigated include modular pressure vessel strategies, modular subsystems, and modular manufacturing approaches to habitat structure. The paper also comments upon the possibility of an integrated habitation strategy using modular components to create all short and long duration habitation elements required in the current exploration architectures.

Some ecological mechanisms to generate habitability in planetary subsurface areas by chemolithotrophic communities: the Río Tinto subsurface ecosystem as a model system.

Science.gov (United States)

Fernández-Remolar, David C; Gómez, Felipe; Prieto-Ballesteros, Olga; Schelble, Rachel T; Rodríguez, Nuria; Amils, Ricardo

2008-02-01

Chemolithotrophic communities that colonize subsurface habitats have great relevance for the astrobiological exploration of our Solar System. We hypothesize that the chemical and thermal stabilization of an environment through microbial activity could make a given planetary region habitable. The MARTE project ground-truth drilling campaigns that sampled cryptic subsurface microbial communities in the basement of the Río Tinto headwaters have shown that acidic surficial habitats are the result of the microbial oxidation of pyritic ores. The oxidation process is exothermic and releases heat under both aerobic and anaerobic conditions. These microbial communities can maintain the subsurface habitat temperature through storage heat if the subsurface temperature does not exceed their maximum growth temperature. In the acidic solutions of the Río Tinto, ferric iron acts as an effective buffer for controlling water pH. Under anaerobic conditions, ferric iron is the oxidant used by microbes to decompose pyrite through the production of sulfate, ferrous iron, and protons. The integration between the physical and chemical processes mediated by microorganisms with those driven by the local geology and hydrology have led us to hypothesize that thermal and chemical regulation mechanisms exist in this environment and that these homeostatic mechanisms could play an essential role in creating habitable areas for other types of microorganisms. Therefore, searching for the physicochemical expression of extinct and extant homeostatic mechanisms through physical and chemical anomalies in the Mars crust (i.e., local thermal gradient or high concentration of unusual products such as ferric sulfates precipitated out from acidic solutions produced by hypothetical microbial communities) could be a first step in the search for biological traces of a putative extant or extinct Mars biosphere.

HEAT OF MARS IS LOVE OF LIFE?! TWO WAYS TO LOOK AT MARS

Directory of Open Access Journals (Sweden)

S. K. Alavipanah

2013-09-01

Full Text Available Earth and Mars travel in neighboring orbits around the sun. Both are rocky planets, but only the earth has the conditions to support life on. Is such a great difference due to their surface temperatures? It is obvious that the surface temperatures of these planets are governed by two factors of: (a the amount of energy they receive from the sun and, (b the composition of their atmospheres. If it is true, we must focus more on the Thermal Remote Sensing on Mars. Since heat is an important factor in any physical, chemical and biological study, it can be said that the heat in the form of love and psychological processes is effective for these studies. In study about life on another planet, not only the thermal characteristics are essential but love or passion in Scientists' efforts that are related to inner heat should also be considered. Therefore, in this paper we review the studies on Mars with the emphasis on the temperature. We consider science, art, literature, and technology as well as any things related to the heat including ice melting, volcanology, soil, morphology, and geothermal. As we believe that it must be bridged between mental and science gaps, shouldn't we make both the art and the science convergent? Therefore, we have used different scientific and art resources to make the role of heat in the Mars clear. We are seeking to answer the question whether the heat can be as a common factor in the researches.

Heat of Mars is Love of LIFE?! Two Ways to Look at Mars

Science.gov (United States)

Alavipanah, S. K.; Van Gasselt, S.; Mulder, N. J.; Nezammahalleh, M. A.

2013-09-01

Earth and Mars travel in neighboring orbits around the sun. Both are rocky planets, but only the earth has the conditions to support life on. Is such a great difference due to their surface temperatures? It is obvious that the surface temperatures of these planets are governed by two factors of: (a) the amount of energy they receive from the sun and, (b) the composition of their atmospheres. If it is true, we must focus more on the Thermal Remote Sensing on Mars. Since heat is an important factor in any physical, chemical and biological study, it can be said that the heat in the form of love and psychological processes is effective for these studies. In study about life on another planet, not only the thermal characteristics are essential but love or passion in Scientists' efforts that are related to inner heat should also be considered. Therefore, in this paper we review the studies on Mars with the emphasis on the temperature. We consider science, art, literature, and technology as well as any things related to the heat including ice melting, volcanology, soil, morphology, and geothermal. As we believe that it must be bridged between mental and science gaps, shouldn't we make both the art and the science convergent? Therefore, we have used different scientific and art resources to make the role of heat in the Mars clear. We are seeking to answer the question whether the heat can be as a common factor in the researches.

Liquid interfacial water and brines in the upper surface of Mars

Science.gov (United States)

Moehlmann, Diedrich

2013-04-01

Liquid interfacial water and brines in the upper surface of Mars Diedrich T.F. Möhlmann DLR Institut für Planetenforschung, Rutherfordstr. 2, D - 12489 Berlin, Germany dirk.moehlmann@dlr.de Interfacial water films and numerous brines are known to remain liquid at temperatures far below 0° C. The physical processes behind are described in some detail. Deliquescence, i.e. the liquefaction of hygroscopic salts at the threshold of a specific "Deliquescence Relative Humidity", is shown to be that process, which on present Mars supports the formation of stable interfacial water and bulk liquids in form of temporary brines on and in a salty upper surface of present Mars in a diurnally temporary and repetitive process. Temperature and relative humidity are the governing conditions for deliquescence (and the counterpart "efflorescence") to evolve. The current thermo-dynamical conditions on Mars support these processes to evolve on present Mars. The deliquescence-driven presence of liquid brines in the soil of the upper surface of Mars can expected to be followed by physical and chemical processes like "surface cementation", down-slope flows, and physical and chemical weathering processes. A remarkable and possibly also biologically relevant evolution towards internally interfacial water bearing structures of dendritic capillaries is related to their freezing - thawing driven formation. The internal walls of these network-pores or -tubes can be covered by films of interfacial water, providing that way possibly habitable crack-systems in soil and rock. These evolutionary processes of networks, driven by their tip-growth, can expected to be ongoing also at present.

Water and Life on Mars

Science.gov (United States)

McKay, Christopher P.; DeVincenzi, Donald (Technical Monitor)

2000-01-01

Mars appears to be cold dry and dead world. However there is good evidence that early in its history it had liquid water, more active volcanism, and a thicker atmosphere. Mars had this earth-like environment over three and a half billion years ago, during the same time that life appeared on Earth. The main question in the exploration of Mars then is the search for a independent origin of life on that planet. Ecosystems in cold, dry locations on Earth - such as the Antarctic - provide examples of how life on Mars might have survived and where to look for fossils. Although the Viking results may indicate that Mars has no life today, there is direct geomorphological evidence that, in the past, Mars had large amounts of liquid water on its surface - possibly due to a thicker atmosphere. From a biological perspective the existence of liquid water, by itself motivates the question of the origin of life on Mars. One of the martian meteorites dates back to this early period and may contain evidence consistent with life. From studies of the Earth's earliest biosphere we know that by 3.5 Gyr. ago, life had originated on Earth and reached a fair degree of biological sophistication. Surface activity and erosion on Earth make it difficult to trace the history of life before the 3.5 Gyr timeframe. Ecosystems in cold, dry locations on Earth - such as the Antarctic - provide examples of how life on Mars might have survived and where to look for fossils.

PHYSICAL ACTIVITY AND EATING HABITS IN UNIVERSITY PROFESSORS: LITERATURE REVIEW

Directory of Open Access Journals (Sweden)

Hector Luiz Rodrigues Munaro

2015-01-01

Full Text Available Increasingly, university professors engage in academic tasks often stressful and sedentary behaviors, making the practice of physical activity and healthier eating habits. The aim of this study was to review the literature Brazilian studies on physical activity and eating habits of university professors .The search was conducted between March and May 2013, in electronic databases. For the delimitation of the study, was used as descriptors: Physical Activity, University Teachers and Eating Habits. At the end of the article selection process, remaining 06 studies that have been described and discussed in the text. And all of a descriptive nature, with small samples with some robust and consistent methodology. The selected studies, regardless of their qualities, point to the need of this population to engage in more physical activity and healthy eating habits programs

PHYSICAL ACTIVITY AND EATING HABITS IN UNIVERSITY PROFESSORS: LITERATURE REVIEW

Directory of Open Access Journals (Sweden)

Hector Luiz Rodrigues Munaro

2015-03-01

Full Text Available Increasingly, university professors engage in academic tasks often stressful and sedentary behaviors, making the practice of physical activity and healthier eating habits. The aim of this study was to review the literature Brazilian studies on physical activity and eating habits of university professors .The search was conducted between March and May 2013, in electronic databases. For the delimitation of the study, was used as descriptors: Physical Activity, University Teachers and Eating Habits. At the end of the article selection process, remaining 06 studies that have been described and discussed in the text. And all of a descriptive nature, with small samples with some robust and consistent methodology. The selected studies, regardless of their qualities, point to the need of this population to engage in more physical activity and healthy eating habits programs.

Anaerobic Nitrogen Fixers on Mars

Science.gov (United States)

Lewis, B. G.

2000-07-01

The conversion of atmospheric nitrogen gas to the protein of living systems is an amazing process of nature. The first step in the process is biological nitrogen fixation, the transformation of N2 to NH3. The phenomenon is crucial for feeding the billions of our species on Earth. On Mars, the same process may allow us to discover how life can adapt to a hostile environment, and render it habitable. Hostile environments also exist on Earth. For example, nothing grows in coal refuse piles due to the oxidation of pyrite and marcasite to sulfuric acid. Yet, when the acidity is neutralized, alfalfa and soybean plants develop root nodules typical of symbiotic nitrogen fixation with Rhizobium species possibly living in the pyritic material. When split open, these nodules exhibited the pinkish color of leghemoglobin, a protein in the nodule protecting the active nitrogen-fixing enzyme nitrogenase against the toxic effects of oxygen. Although we have not yet obtained direct evidence of nitrogenase activity in these nodules (reduction of acetylene to ethylene, for example), these findings suggested the possibility that nitrogen fixation was taking place in this hostile, non-soil material. This immediately raises the possibility that freeliving anaerobic bacteria which fix atmospheric nitrogen on Earth, could do the same on Mars.

EquiMar

DEFF Research Database (Denmark)

Johnstone, C. M.; McCombes, T.; Bahaj, A. S.

2011-01-01

the performance evaluation of such systems in order to address this deficiency. This paper reports the development of a set of ‘Best Practices’ within the ECFPVII EquiMar project to be adopted for the performance quantification of wave and tidal energy converters as they evolve from an engineering concept......At the present time there are no approved standards or recognised best practices being implemented for the performance appraisal and benchmarking of wave and tidal energy converters. As such, this develops considerable misunderstanding between device developers, testing centres, investors....../ financiers etc when attempting to quantify the performance of a device since it makes it very difficult to reference and benchmark the performance of a marine energy converter. The EC Framework Programme VII EquiMar project has set out to develop a suite of Best Practices to be adopted when undertaking...

Bringing a Chemical Laboratory Named Sam to Mars on the 2011 Curiosity Rover

Science.gov (United States)

Mahaffy, P. R.; Bleacher, L.; Jones, A.; Conrad, P. G.; Cabane, M.; Webster, C. R.; Atreya, S. A.; Manning, H.

2010-01-01

An important goal of upcoming missions to Mars is to understand if life could have developed there. The task of the Sample Analysis at Mars (SAM) suite of instruments [1] and the other Curiosity investigations [2] is to move us steadily toward that goal with an assessment of the habitability of our neighboring planet through a series of chemical and geological measurements. SAM is designed to search for organic compounds and inorganic volatiles and measure isotope ratios. Other instruments on Curiosity will provide elemental analysis and identify minerals. SAM will analyze both atmospheric samples and gases evolved from powdered rocks that may have formed billions of years ago with Curiosity providing access to interesting sites scouted by orbiting cameras and spectrometers.

Mars Orbiter Camera Views the 'Face on Mars' - Best View from Viking

Science.gov (United States)

1998-01-01

Shortly after midnight Sunday morning (5 April 1998 12:39 AM PST), the Mars Orbiter Camera (MOC) on the Mars Global Surveyor (MGS) spacecraft successfully acquired a high resolution image of the 'Face on Mars' feature in the Cydonia region. The image was transmitted to Earth on Sunday, and retrieved from the mission computer data base Monday morning (6 April 1998). The image was processed at the Malin Space Science Systems (MSSS) facility 9:15 AM and the raw image immediately transferred to the Jet Propulsion Laboratory (JPL) for release to the Internet. The images shown here were subsequently processed at MSSS.The picture was acquired 375 seconds after the spacecraft's 220th close approach to Mars. At that time, the 'Face', located at approximately 40.8o N, 9.6o W, was 275 miles (444 km) from the spacecraft. The 'morning' sun was 25o above the horizon. The picture has a resolution of 14.1 feet (4.3 meters) per pixel, making it ten times higher resolution than the best previous image of the feature, which was taken by the Viking Mission in the mid-1970's. The full image covers an area 2.7 miles (4.4 km) wide and 25.7 miles (41.5 km) long.This Viking Orbiter image is one of the best Viking pictures of the area Cydonia where the 'Face' is located. Marked on the image are the 'footprint' of the high resolution (narrow angle) Mars Orbiter Camera image and the area seen in enlarged views (dashed box). See PIA01440-1442 for these images in raw and processed form.Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

PDS4 vs PDS3 - A Comparison of PDS Data for Two Mars Rovers - Existing Mars Curiosity Mission Mass Spectrometer (SAM) PDS3 Data vs Future ExoMars Rover Mass Spectrometer (MOMA) PDS4 Data

Science.gov (United States)

Lyness, E.; Franz, H. B.; Prats, B.

2017-12-01

The Sample Analysis at Mars (SAM) instrument is a suite of instruments on Mars aboard the Mars Science Laboratory rover. Centered on a mass spectrometer, SAM delivers its data to the PDS Atmosphere's node in PDS3 format. Over five years on Mars the process of operating SAM has evolved and extended significantly from the plan in place at the time the PDS3 delivery specification was written. For instance, SAM commonly receives double or even triple sample aliquots from the rover's drill. SAM also stores samples in spare cups for long periods of time for future analysis. These unanticipated operational changes mean that the PDS data deliveries are absent some valuable metadata without which the data can be confusing. The Mars Organic Molecule Analyzer (MOMA) instrument is another suite of instruments centered on a mass spectrometer bound for Mars. MOMA is part of the European ExoMars rover mission schedule to arrive on Mars in 2021. While SAM and MOMA differ in some important scientific ways - MOMA uses an linear ion trap compared to the SAM quadropole mass spectrometer and MOMA has a laser desorption experiment that SAM lacks - the data content from the PDS point of view is comparable. Both instruments produce data containing mass spectra acquired from solid samples collected on the surface of Mars. The MOMA PDS delivery will make use of PDS4 improvements to provide a metadata context to the data. The MOMA PDS4 specification makes few assumptions of the operational processes. Instead it provides a means for the MOMA operators to provide the important contextual metadata that was unanticipated during specification development. Further, the software tools being developed for instrument operators will provide a means for the operators to add this crucial metadata at the time it is best know - during operations.

SGTR assessment using MARS

International Nuclear Information System (INIS)

Raines, J.C.; Dawson, S.M.; Deitke, B.; Henry, R.E.

1996-01-01

During the course of a plant accident, a consistent understanding of the plant response is vital to support an accident manager's decision making process. One tool that can provide assistance to the plant staff in assessing conditions in the plant during accident conditions is the MAAP Accident Response System (MARS) software. During an accident, MARS utilizes the on-line data from the plant instrumentation to initialize the Modular Accident Analysis Program (MAAP) code. Once initialized, MARS tracks and characterizes the plant behavior through the use of integrated logic modules. These logic modules provide the user with important information about the status of systems and the possible cause of the accident. The MARS logic modules evaluate relevant available plant instrumentation and the observations of the operating staff using fuzzy logic. The fuzzy logic is applied to provide a transition between areas where one is absolutely sure that a situation has not occurred to a condition where one is absolutely certain that a situation has occurred. One example of the use of logic modules in MARS is illustrated by that used to assess if a steam generator tube rupture (SGTR) event has occurred. Each piece of relevant plant data is evaluated to determine if it is consistent with the symptoms of a SGTR. Each of the evaluations for the individual plant instruments and the operating staff observations are assembled to determine an overall confidence which characterizes the likelihood that a SGTR is occurring. Additional MARS logic modules are used to determine confidence levels for other types of accident events. The conclusions arrived at by each individual logic module are expressed as confidence levels. The logic module confidence levels can be graphically displayed using the MARS Graphical Users Interface (GUI), to indicate the confidence level MARS has assessed for each accident type. The GUI shows the identification of the possible accident types, but is not limited

Why, from a Life Sciences Perspective, This Mission to Mars?

Science.gov (United States)

McKay, Christopher P.; DeVincenzi, Donald (Technical Monitor)

2002-01-01

Mars may have had water and life early in its history and this make it a key target for robotic and human exploration. Extensive human exploration of Mars will of necessity depend on life support systems that rely on agricultural plants. If current concept for recreating, a biosphere on Mars are implemented this would involve widespread use of plants, particularly species from Arctic and alpine environments.

The Sample at Mars Analysis (SAM) Detections of CO2 and CO in Sedimentary Material from Gale Crater, Mars: Implications for the Presence of Organic Carbon and Microbial Habitability on Mars

Science.gov (United States)

Sutter, Brad; Eigenbrode, Jennifer L.; Steele, Andrew; Ming, Douglas W.

2016-01-01

Sedimentary rock samples heated to 860 degrees Centigrade in the SAM (Sample at Mars) instrument evolved CO2 and CO indicating the presence of organic-carbon(C) in Gale Crater materials. Martian or exogenous (meteoritic, interplanetary dust) CO2 and CO could be derived from combustion of simple organics (less than 300 degrees Centigrade), complex refractory organics/amorphous carbon (300-600 degrees Centigrade), and/or magmatic carbon (greater than 600 degrees Centigrade) as result of thermal decomposition of Gale Crater perchlorates, and sulfates present that produce O2. Oxidized organic compounds could also evolve CO2 and CO over broad temperature range (150 to 800 degrees Centigrade) and such organics are expected on Mars via exogenous sources. Alternatively, organic-C could also have been oxidized to carboxylic acids [e.g, mellitic acid (RCOOH), acetate (CH3CO2-), and oxalates (C2O42-)] by oxidative radiolytic weathering, or other oxidation processes. The presence of oxidized organics is consistent with the limited detection of reduced organic-C phases by the SAM-gas chromatography. Organic-C content as determined by CO2 and CO contents could range between 800 and 2400 parts per million C indicating that substantial organic-C component is present in Gale Crater. There are contributions from SAM background however, even in worst-case scenarios, this would only account for as much as half of the detected CO2 and CO. Nevertheless, if organic-C levels were assumed to have existed in a reduced form on ancient Mars and this was bioavailable C, then less than 1 percent of C in Gale Crater sediments could have supported an exclusively heterotrophic microbial population of 1 by 10 (sup 5) cells per gram sediment (assumes 9 by 10 (sup -7) microgram per cell and 0.5 micrograms C per microgram cell). While other essential nutrients (e.g., S and P) could be limiting, organic-C contents, may have been sufficient to support limited heterotrophic microbial populations on

Silicates Eroded under Simulated Martian Conditions Effectively Kill Bacteria—A Challenge for Life on Mars

DEFF Research Database (Denmark)

Bak, Ebbe Norskov; Larsen, Michael G.; Moeller, Ralf

2017-01-01

The habitability of Mars is determined by the physical and chemical environment. The effect of low water availability, temperature, low atmospheric pressure and strong UV radiation has been extensively studied in relation to the survival of microorganisms. In addition to these stress factors......, it was recently found that silicates exposed to simulated saltation in a Mars-like atmosphere can lead to a production of reactive oxygen species. Here, we have investigated the stress effect induced by quartz and basalt abraded in Mars-like atmospheres by examining the survivability of the three microbial model...... of the basalt samples to oxygen after abrasion led to a significant reduction in the stress effect. Abraded quartz was generally less toxic than abraded basalt. We suggest that the stress effect of abraded silicates may be caused by a production of reactive oxygen species and enhanced by transition metal ions...

The Icebreaker Life Mission to Mars: a search for biomolecular evidence for life.

Science.gov (United States)

McKay, Christopher P; Stoker, Carol R; Glass, Brian J; Davé, Arwen I; Davila, Alfonso F; Heldmann, Jennifer L; Marinova, Margarita M; Fairen, Alberto G; Quinn, Richard C; Zacny, Kris A; Paulsen, Gale; Smith, Peter H; Parro, Victor; Andersen, Dale T; Hecht, Michael H; Lacelle, Denis; Pollard, Wayne H

2013-04-01

The search for evidence of life on Mars is the primary motivation for the exploration of that planet. The results from previous missions, and the Phoenix mission in particular, indicate that the ice-cemented ground in the north polar plains is likely to be the most recently habitable place that is currently known on Mars. The near-surface ice likely provided adequate water activity during periods of high obliquity, ≈ 5 Myr ago. Carbon dioxide and nitrogen are present in the atmosphere, and nitrates may be present in the soil. Perchlorate in the soil together with iron in basaltic rock provides a possible energy source for life. Furthermore, the presence of organics must once again be considered, as the results of the Viking GCMS are now suspect given the discovery of the thermally reactive perchlorate. Ground ice may provide a way to preserve organic molecules for extended periods of time, especially organic biomarkers. The Mars Icebreaker Life mission focuses on the following science goals: (1) Search for specific biomolecules that would be conclusive evidence of life. (2) Perform a general search for organic molecules in the ground ice. (3) Determine the processes of ground ice formation and the role of liquid water. (4) Understand the mechanical properties of the martian polar ice-cemented soil. (5) Assess the recent habitability of the environment with respect to required elements to support life, energy sources, and possible toxic elements. (6) Compare the elemental composition of the northern plains with midlatitude sites. The Icebreaker Life payload has been designed around the Phoenix spacecraft and is targeted to a site near the Phoenix landing site. However, the Icebreaker payload could be supported on other Mars landing systems. Preliminary studies of the SpaceX Dragon lander show that it could support the Icebreaker payload for a landing either at the Phoenix site or at midlatitudes. Duplicate samples could be cached as a target for possible return by

Nuclear Radiation Fields on the Mars Surface: Risk Analysis for Long-term Living Environment

Science.gov (United States)

Anderson, Brooke M.; Clowdsley, Martha S.; Qualls, Garry D.; Nealy, John E.

2005-01-01

Mars, our nearest planet outward from the sun, has been targeted for several decades as a prospective site for expanded human habitation. Background space radiation exposures on Mars are expected to be orders of magnitude higher than on Earth. Recent risk analysis procedures based on detailed dosimetric techniques applicable to sensitive human organs have been developed along with experimental data regarding cell mutation rates resulting from exposures to a broad range of particle types and energy spectra. In this context, simulated exposure and subsequent risk for humans in residence on Mars are examined. A conceptual habitat structure, CAD-modeled with duly considered inherent shielding properties, has been implemented. Body self-shielding is evaluated using NASA standard computerized male and female models. The background environment is taken to consist not only of exposure from incident cosmic ray ions and their secondaries, but also include the contribution from secondary neutron fields produced in the tenuous atmosphere and the underlying regolith.

Numerical quantification of habitability in serpentinizing systems

Science.gov (United States)

Som, S.; Alperin, M. J.; Hoehler, T. M.

2012-12-01

The likely presence of liquid water in contact with olivine-bearing rocks on Mars, the detection of serpentine minerals and of methane emissions possibly consistent with serpentinization, and the observation of serpentine-associated methane-cycling communities on Earth have all led to excitement over the potential of such systems to host life on Mars, even into the present day. However, the habitability of subsurface serpentinizing systems on Mars does not necessarily follow from these qualitative observations. In particular, while the production of H2 during serpentinization could provide methanogens with a needed substrate, the alkaline conditions and corresponding potential for carbon limitation that arise in concert are negatives against which H2 supply must be balanced. We considered this balance via a coupled geochemical-bioenergetic model that weighs the outputs of serpentinization against the metabolic requirements of methanogenesis, in an energetic frame of reference. Serpentinization is modeled using the "Geochemist's Workbench" (GWB) whereby ultramafic harzburgite rocks are reacted with oxygen and sulfate depleted seawater. Reaction kinetics are not explicitly considered, but comparable effects of partial reaction are approximated by assuming post-reaction dilution of equilibrated fluids. The output of GWB serves as the input to the bioenergetic model, which calculates methanogenic energy yields based on spherically-symmetrical diffusion of substrates to a cell followed by reaction at the diffusion-limited rate. Membrane selectivity for substrate transport is explicitly considered. Results will be report updates for two scenarios: (i) High temperature serpentinization followed by cooling and transport of equilibrated fluid to a lower temperature regime accessible to biology; (ii) Serpentinization within the biologically-tolerated range of temperatures. Such coupled models demonstrate that environmental variability with respect to both water-rock reaction

In situ NIR reflectance and LIBS measurements in lava tubes in preparation for future Mars missions

Science.gov (United States)

Leveille, R.; Sobron, P.

2017-12-01

The ATiLT (Astrobiology Training in Lava Tubes) program addresses Mars astrobiology exploration objectives by performing field work and instrumental analyses in lava tubes as high fidelity analog environments to putative lava tubes on Mars. The main field location for ATiLT is the Lava Beds National Monument (LABE) in Northern California. LABE is situated on the lower north flank of the Medicine Lake Volcano of the Cascade arc. This location features hundreds of caves, most of which are relatively shallow, typically well above the water table, reaching 20-45m below land surface at their maximum depth. Some LABE caves feature `cold sinks' where cold air sinks and becomes trapped in deeper cave passages, thus allowing perennial ice to accumulate despite above freezing surface temperatures. Several lava tube caves in LABE also contain seasonal or perennial ice accumulations, which makes them excellent analogs to Mars lava tubes where the presence of ice has been predicted. While lava tubes are very attractive systems to test hypotheses related to habitability and the possibility for life on Mars, at present there are no comprehensive in-situ instrument-driven characterizations of the mineralogy and geochemistry of lava tubes. ATiLT fills this gap by providing detailed, in-situ investigations with scientific instruments relevant to Mars exploration. Our aim is to help constrain future exploration targets on Mars and define future mission operations and requirements. For this purpose, in May 2017 we carried out a field campaign in several lava tubes at LABE. We deployed two miniature spectroscopic sensors suitable for dark, humid, cave conditions: NIR reflectance (1-5 μm) and LIBS (300-900 nm). The advantages of combining NIR reflectance and LIBS are evident: LIBS can reveal the relative concentration of major (and often trace) elements present in a bulk sample, whereas NIR reflectance yields information on the individual mineral species and their chemical and

The Aristotelian conception of habit and its contribution to human neuroscience

Directory of Open Access Journals (Sweden)

Javier eBernacer

2014-11-01

Full Text Available The notion of habit used in neuroscience is an inheritance from a particular theoretical origin, whose main source is William James. Thus, habits have been characterized as rigid, automatic, unconscious, and opposed to goal-directed actions. This analysis leaves unexplained several aspects of human behavior and cognition where habits are of great importance. We intend to demonstrate the utility that another philosophical conception of habit, the Aristotelian, may have for neuroscientific research. We first summarize the current notion of habit in neuroscience, its philosophical inspiration and the problems that arise from it, mostly centered on the sharp distinction between goal-directed actions and habitual behavior. We then introduce the Aristotelian view and we compare it with that of William James. For Aristotle, a habit is an acquired disposition to perform certain types of action. If this disposition involves an enhanced cognitive control of actions, it can be considered a habit-as-learning. The current view of habit in neuroscience, which lacks cognitive control and we term habit-as-routine, is also covered by the Aristotelian conception. He classifies habits into three categories: 1 theoretical, or the retention of learning understood as knowing that x is so; 2 behavioral, through which the agent achieves a rational control of emotion-permeated behavior (knowing how to behave; and 3 technical or learned skills (knowing how to make or to do. Finally, we propose new areas of research where this novel conception of habit could serve as a framework concept, from the cognitive enrichment of actions to the role of habits in pathological conditions. In all, this contribution may shed light on the understanding of habits as an important feature of human action. Habits, viewed as cognitively controlled behaviors that in turn improve cognitive control of behavior, are a crucial resource for enhancing human learning and behavioral plasticity.

Architectural and Behavioral Systems Design Methodology and Analysis for Optimal Habitation in a Volume-Limited Spacecraft for Long Duration Flights

Science.gov (United States)

Kennedy, Kriss J.; Lewis, Ruthan; Toups, Larry; Howard, Robert; Whitmire, Alexandra; Smitherman, David; Howe, Scott

2016-01-01

As our human spaceflight missions change as we reach towards Mars, the risk of an adverse behavioral outcome increases, and requirements for crew health, safety, and performance, and the internal architecture, will need to change to accommodate unprecedented mission demands. Evidence shows that architectural arrangement and habitability elements impact behavior. Net habitable volume is the volume available to the crew after accounting for elements that decrease the functional volume of the spacecraft. Determination of minimum acceptable net habitable volume and associated architectural design elements, as mission duration and environment varies, is key to enabling, maintaining, andor enhancing human performance and psychological and behavioral health. Current NASA efforts to derive minimum acceptable net habitable volumes and study the interaction of covariates and stressors, such as sensory stimulation, communication, autonomy, and privacy, and application to internal architecture design layouts, attributes, and use of advanced accommodations will be presented. Furthermore, implications of crew adaptation to available volume as they transfer from Earth accommodations, to deep space travel, to planetary surface habitats, and return, will be discussed.

Europe is going to Mars

Science.gov (United States)

1999-06-01

The Agency's Science Programme Committee (SPC) approved Mars Express after ESA's Council, meeting at ministerial level in Brussels on 11 and 12 May, had agreed the level of the science budget for the next 4 years, just enough to make the mission affordable. "Mars Express is a mission of opportunity and we felt we just had to jump in and do it. We are convinced it will produce first-rate science", says Hans Balsiger, SPC chairman. As well as being a first for Europe in Mars exploration, Mars Express will pioneer new, cheaper ways of doing space science missions. "With a total cost of just 150 million euros, Mars Express will be the cheapest Mars mission ever undertaken", says Roger Bonnet, ESA's Director of Science. Mars Express will be launched in June 2003. When it arrives at the red planet six months later, it will begin to search for water and life. Seven instruments, provided by space research institutes throughout Europe, will make observations from the main spacecraft as it orbits the planet. Just before the spacecraft arrives, it will release a small lander, provided by research institutes in the UK, that will journey on to the surface to look for signs of life. The lander is called Beagle 2 after the ship in which Charles Darwin sailed round the world in search of evidence supporting his theory of evolution. But just as Darwin had to raise the money for his trip, so the search is on for public and private finance for Beagle 2. "Beagle 2 is an extremely important element of the mission", says Bonnet. Europe's space scientists have envisaged a mission to Mars for over fifteen years. But limited funding has prevented previous proposals from going ahead. The positioning of the planets in 2003, however, offers a particularly favourable passage to the red planet - an opportunity not to be missed. Mars Express will be joined by an international flotilla of spacecraft that will also be using this opportunity to work together on scientific questions and pave the way

Are "Habitable" Exoplanets Really Habitable? -A perspective from atmospheric loss

Science.gov (United States)

Dong, C.; Huang, Z.; Jin, M.; Lingam, M.; Ma, Y. J.; Toth, G.; van der Holst, B.; Airapetian, V.; Cohen, O.; Gombosi, T. I.

2017-12-01

In the last two decades, the field of exoplanets has witnessed a tremendous creative surge. Research in exoplanets now encompasses a wide range of fields ranging from astrophysics to heliophysics and atmospheric science. One of the primary objectives of studying exoplanets is to determine the criteria for habitability, and whether certain exoplanets meet these requirements. The classical definition of the Habitable Zone (HZ) is the region around a star where liquid water can exist on the planetary surface given sufficient atmospheric pressure. However, this definition largely ignores the impact of the stellar wind and stellar magnetic activity on the erosion of an exoplanet's atmosphere. Amongst the many factors that determine habitability, understanding the mechanisms of atmospheric loss is of paramount importance. We will discuss the impact of exoplanetary space weather on climate and habitability, which offers fresh insights concerning the habitability of exoplanets, especially those orbiting M-dwarfs, such as Proxima b and the TRAPPIST-1 system. For each case, we will demonstrate the importance of the exoplanetary space weather on atmospheric ion loss and habitability.

Hydrogen escape from Mars enhanced by deep convection in dust storms

Science.gov (United States)

Heavens, Nicholas G.; Kleinböhl, Armin; Chaffin, Michael S.; Halekas, Jasper S.; Kass, David M.; Hayne, Paul O.; McCleese, Daniel J.; Piqueux, Sylvain; Shirley, James H.; Schofield, John T.

2018-02-01

Present-day water loss from Mars provides insight into Mars's past habitability1-3. Its main mechanism is thought to be Jeans escape of a steady hydrogen reservoir sourced from odd-oxygen reactions with near-surface water vapour2, 4,5. The observed escape rate, however, is strongly variable and correlates poorly with solar extreme-ultraviolet radiation flux6-8, which was predicted to modulate escape9. This variability has recently been attributed to hydrogen sourced from photolysed middle atmospheric water vapour10, whose vertical and seasonal distribution is only partly characterized and understood11-13. Here, we report multi-annual observational estimates of water content and dust and water transport to the middle atmosphere from Mars Climate Sounder data. We provide strong evidence that the transport of water vapour and ice to the middle atmosphere by deep convection in Martian dust storms can enhance hydrogen escape. Planet-encircling dust storms can raise the effective hygropause (where water content rapidly decreases to effectively zero) from 50 to 80 km above the areoid (the reference equipotential surface). Smaller dust storms contribute to an annual mode in water content at 40-50 km that may explain seasonal variability in escape. Our results imply that Martian atmospheric chemistry and evolution can be strongly affected by the meteorology of the lower and middle atmosphere of Mars.

Mushroom bodies regulate habit formation in Drosophila.

Science.gov (United States)

Brembs, Björn

2009-08-25

To make good decisions, we evaluate past choices to guide later decisions. In most situations, we have the opportunity to simultaneously learn about both the consequences of our choice (i.e., operantly) and the stimuli associated with correct or incorrect choices (i.e., classically). Interestingly, in many species, including humans, these learning processes occasionally lead to irrational decisions. An extreme case is the habitual drug user consistently administering the drug despite the negative consequences, but we all have experience with our own, less severe habits. The standard animal model employs a combination of operant and classical learning components to bring about habit formation in rodents. After extended training, these animals will press a lever even if the outcome associated with lever-pressing is no longer desired. In this study, experiments with wild-type and transgenic flies revealed that a prominent insect neuropil, the mushroom bodies (MBs), regulates habit formation in flies by inhibiting the operant learning system when a predictive stimulus is present. This inhibition enables generalization of the classical memory and prevents premature habit formation. Extended training in wild-type flies produced a phenocopy of MB-impaired flies, such that generalization was abolished and goal-directed actions were transformed into habitual responses.

The crucial role of habits in energy consumption: an evolutionary approach on changing current patterns

Energy Technology Data Exchange (ETDEWEB)

Marechal, Kevin (Centre for Economic and Social Studies on the Environment (CESSE), Univ. Libre de Bruxelles, Univ. d' Europe (Belgium)). e-mail: kevin.marechal@ulb.ac.be

2009-07-01

A substantial body of literature has shown that our behaviour is often guided by habits. The existence of habits - not fully conscious forms of behaviour - is important as it contradicts rational choice theory. Their presence thus calls for the setting of new instruments as they make it unlikely that consumers be capable of exercising control over their energy consumption in reaction to given incentives. This is further increased in the evolutionary perspective where the current carbon-based Socio-Technical System constraints and shapes consumers' choices through structural forces. Habits being potentially 'counterintentional', they may explain the 'efficiency paradox' in energy as well as the continued increase of energy consumption despite the rising environmental awareness among the population. Policies aiming at reducing energy consumption should thus specifically address the performance context of habits. For instance, targeting new residents has proven to be more effective given that their preceding habits have been disturbed. The results of our empirical analysis confirm this idea by showing how a change of context makes people more receptive to a proposed measure. Our analysis of the role played by habits also suggests that individuals do not consider the need to change existing habits as an obstacle even though this is contradicted implicitly in the answers they provided to open questions. This 'unconsciousness' is one of the most delicate features of habits and it should thus be accounted for when designing measures. Given the other characteristics of habits, the joint use of feedbacks and commitment strategies appears promising.

Thermal-orbital coupled tidal heating and habitability of Martian-sized extrasolar planets around M stars

International Nuclear Information System (INIS)

Shoji, D.; Kurita, K.

2014-01-01

M-type stars are good targets in the search for habitable extrasolar planets. Due to their low effective temperatures, the habitable zone of M stars is very close to the stars themselves. For planets that are close to their stars, tidal heating plays an important role in thermal and orbital evolutions, especially when the planet's orbit has a relatively large eccentricity. Although tidal heating interacts with the thermal state and the orbit of the planet, such coupled calculations for extrasolar planets around M stars have not been conducted. We perform coupled calculations using simple structural and orbital models and analyze the thermal state and habitability of a terrestrial planet. Considering this planet to be Martian-sized, the tide heats up and partially melts the mantle, maintaining an equilibrium state if the mass of the star is less than 0.2 times the mass of the Sun and the initial eccentricity of the orbit is more than 0.2. The reduction of heat dissipation due to the melted mantle allows the planet to stay in the habitable zone for more than 10 Gyr even though the orbital distance is small. The surface heat flux at the equilibrium state is between that of Mars and Io. The thermal state of the planet mainly depends on the initial value of the eccentricity and the mass of the star.

Thermal-orbital coupled tidal heating and habitability of Martian-sized extrasolar planets around M stars

Energy Technology Data Exchange (ETDEWEB)

Shoji, D.; Kurita, K. [Earthquake Research Institute, University of Tokyo, Tokyo (Japan)

2014-07-01

M-type stars are good targets in the search for habitable extrasolar planets. Due to their low effective temperatures, the habitable zone of M stars is very close to the stars themselves. For planets that are close to their stars, tidal heating plays an important role in thermal and orbital evolutions, especially when the planet's orbit has a relatively large eccentricity. Although tidal heating interacts with the thermal state and the orbit of the planet, such coupled calculations for extrasolar planets around M stars have not been conducted. We perform coupled calculations using simple structural and orbital models and analyze the thermal state and habitability of a terrestrial planet. Considering this planet to be Martian-sized, the tide heats up and partially melts the mantle, maintaining an equilibrium state if the mass of the star is less than 0.2 times the mass of the Sun and the initial eccentricity of the orbit is more than 0.2. The reduction of heat dissipation due to the melted mantle allows the planet to stay in the habitable zone for more than 10 Gyr even though the orbital distance is small. The surface heat flux at the equilibrium state is between that of Mars and Io. The thermal state of the planet mainly depends on the initial value of the eccentricity and the mass of the star.

Observations of Crew Dynamics During Mars Analog Simulations

Science.gov (United States)

Cusack, Stacy L.

2009-01-01

Crewmembers on Mars missions will face new and unique challenges compared to those in close communications proximity to Mission Control centers. Crews on Mars will likely become more autonomous and responsible for their day-to-day planning. These explorers will need to make frequent real time decisions without the assistance of large ground support teams. Ground-centric control will no longer be an option due to the communications delays. As a result of the new decision making model, crew dynamics and leadership styles of future astronauts may become significantly different from the demands of today. As a volunteer for the Mars Society on two Mars analog missions, this presenter will discuss observations made during isolated, surface exploration simulations. The need for careful crew selections, not just based on individual skill sets, but on overall team interactions becomes apparent very quickly when the crew is planning their own days and deciding their own priorities. Even more important is the selection of a Mission Commander who can lead a team of highly skilled individuals with strong and varied opinions in a way that promotes crew consensus, maintains fairness, and prevents unnecessary crew fatigue.

Large wind ripples on Mars: A record of atmospheric evolution

OpenAIRE

Lapotre, M. G. A.; Ewing, R. C.; Lamb, M. P.; Fischer, W. W.; Grotzinger, J. P.; Rubin, D. M.; Lewis, K. W.; Ballard, M. J.; Daybell, M.; Gupta, S.; Banham, S. G.; Bridges, N. T.; Des Marais, D. J.; Fraeman, A. A.; Grant, J. A.

2016-01-01

Wind blowing over sand on Earth produces decimeter-wavelength ripples and hundred-meter– to kilometer-wavelength dunes: bedforms of two distinct size modes. Observations from the Mars Science Laboratory Curiosity rover and the Mars Reconnaissance Orbiter reveal that Mars hosts a third stable wind-driven bedform, with meter-scale wavelengths. These bedforms are spatially uniform in size and typically have asymmetric profiles with angle-of-repose lee slopes and sinuous crest lines, making them ...

The Coevolution of Life and Environment on Mars: An Ecosystem Perspective on the Robotic Exploration of Biosignatures

Science.gov (United States)

Cabrol, Nathalie A.

2018-01-01

Earth's biological and environmental evolution are intertwined and inseparable. This coevolution has become a fundamental concept in astrobiology and is key to the search for life beyond our planet. In the case of Mars, whether a coevolution took place is unknown, but analyzing the factors at play shows the uniqueness of each planetary experiment regardless of similarities. Early Earth and early Mars shared traits. However, biological processes on Mars, if any, would have had to proceed within the distinctive context of an irreversible atmospheric collapse, greater climate variability, and specific planetary characteristics. In that, Mars is an important test bed for comparing the effects of a unique set of spatiotemporal changes on an Earth-like, yet different, planet. Many questions remain unanswered about Mars' early environment. Nevertheless, existing data sets provide a foundation for an intellectual framework where notional coevolution models can be explored. In this framework, the focus is shifted from planetary-scale habitability to the prospect of habitats, microbial ecotones, pathways to biological dispersal, biomass repositories, and their meaning for exploration. Critically, as we search for biosignatures, this focus demonstrates the importance of starting to think of early Mars as a biosphere and vigorously integrating an ecosystem approach to landing site selection and exploration.

The Coevolution of Life and Environment on Mars: An Ecosystem Perspective on the Robotic Exploration of Biosignatures

Science.gov (United States)

2018-01-01

Abstract Earth's biological and environmental evolution are intertwined and inseparable. This coevolution has become a fundamental concept in astrobiology and is key to the search for life beyond our planet. In the case of Mars, whether a coevolution took place is unknown, but analyzing the factors at play shows the uniqueness of each planetary experiment regardless of similarities. Early Earth and early Mars shared traits. However, biological processes on Mars, if any, would have had to proceed within the distinctive context of an irreversible atmospheric collapse, greater climate variability, and specific planetary characteristics. In that, Mars is an important test bed for comparing the effects of a unique set of spatiotemporal changes on an Earth-like, yet different, planet. Many questions remain unanswered about Mars' early environment. Nevertheless, existing data sets provide a foundation for an intellectual framework where notional coevolution models can be explored. In this framework, the focus is shifted from planetary-scale habitability to the prospect of habitats, microbial ecotones, pathways to biological dispersal, biomass repositories, and their meaning for exploration. Critically, as we search for biosignatures, this focus demonstrates the importance of starting to think of early Mars as a biosphere and vigorously integrating an ecosystem approach to landing site selection and exploration. Key Words: Astrobiology—Biosignatures—Coevolution of Earth and life—Mars. Astrobiology 18, 1–27. PMID:29252008

The Coevolution of Life and Environment on Mars: An Ecosystem Perspective on the Robotic Exploration of Biosignatures.

Science.gov (United States)

Cabrol, Nathalie A

2018-01-01

Earth's biological and environmental evolution are intertwined and inseparable. This coevolution has become a fundamental concept in astrobiology and is key to the search for life beyond our planet. In the case of Mars, whether a coevolution took place is unknown, but analyzing the factors at play shows the uniqueness of each planetary experiment regardless of similarities. Early Earth and early Mars shared traits. However, biological processes on Mars, if any, would have had to proceed within the distinctive context of an irreversible atmospheric collapse, greater climate variability, and specific planetary characteristics. In that, Mars is an important test bed for comparing the effects of a unique set of spatiotemporal changes on an Earth-like, yet different, planet. Many questions remain unanswered about Mars' early environment. Nevertheless, existing data sets provide a foundation for an intellectual framework where notional coevolution models can be explored. In this framework, the focus is shifted from planetary-scale habitability to the prospect of habitats, microbial ecotones, pathways to biological dispersal, biomass repositories, and their meaning for exploration. Critically, as we search for biosignatures, this focus demonstrates the importance of starting to think of early Mars as a biosphere and vigorously integrating an ecosystem approach to landing site selection and exploration. Key Words: Astrobiology-Biosignatures-Coevolution of Earth and life-Mars. Astrobiology 18, 1-27.

What and how can affect the exploration of Mars

Science.gov (United States)

Vidmachenko, A. P.; Morozhenko, A. V.

2017-05-01

Going to Mars, astronauts are deprived of the protection of the magnetic field. And for 15 months of flight to Mars and back astronaut will receive maximum permissible for his entire career, a dose of radiation of 1 sievert. And when powerful flash can occur on the sun, the dose of radiation will grow by an order of magnitude and can even kill the crew. The radiation background in the orbit of Mars is more than 2.2 times higher than the radiation background at the Earth's orbital station. The smallest toxic dust on Mars is also can interfere with the colonization of Mars. This dust contains a large number of toxic compounds such as perchlorates, minerals of gypsum, compounds of chromium, fine-grained salts of silicic acid, etc. The listed above factors make forced to think seriously about the possibility of organizing a Mars mission, even in the distant future.

Car-use habits

DEFF Research Database (Denmark)

Møller, Berit Thorup; Thøgersen, John

2008-01-01

It is often claimed that many drivers use their private car rather habitually. The claim gains credibility from the fact that travelling to many everyday destinations fulfils all the prerequisites for habit formation: it is recurring, performed under stable circumstances and produces rewarding...... consequences. Since the decision is made quite automatically and only one choice alternative is considered (the habitually chosen one), behaviour guided by habit is difficult to change. The implications of car use habits for converting drivers to commuters using public transportation is analysed based...... to do so, car use habit, and the interaction between the two, confirms the theory-derived hypothesis that car use habits act as an obstacle to the transformation of intentions to commute by public transportation into action....

Mars Pathfinder and Mars Global Surveyor Outreach Compilation

Science.gov (United States)

1999-09-01

This videotape is a compilation of the best NASA JPL (Jet Propulsion Laboratory) videos of the Mars Pathfinder and Mars Global Surveyor missions. The mission is described using animation and narration as well as some actual footage of the entire sequence of mission events. Included within these animations are the spacecraft orbit insertion; descent to the Mars surface; deployment of the airbags and instruments; and exploration by Sojourner, the Mars rover. JPL activities at spacecraft control during significant mission events are also included at the end. The spacecraft cameras pan the surrounding Mars terrain and film Sojourner traversing the surface and inspecting rocks. A single, brief, processed image of the Cydonia region (Mars face) at an oblique angle from the Mars Global Surveyor is presented. A description of the Mars Pathfinder mission, instruments, landing and deployment process, Mars approach, spacecraft orbit insertion, rover operation are all described using computer animation. Actual color footage of Sojourner as well as a 360 deg pan of the Mars terrain surrounding the spacecraft is provided. Lower quality black and white photography depicting Sojourner traversing the Mars surface and inspecting Martian rocks also is included.

Planning to break unwanted habits: habit strength moderates implementation intention effects on behaviour change.

Science.gov (United States)

Webb, Thomas L; Sheeran, Paschal; Luszczynska, Aleksandra

2009-09-01

Implementation intention formation promotes effective goal striving and goal attainment. However, little research has investigated whether implementation intentions promote behaviour change when people possess strong antagonistic habits. Experiment 1 developed relatively habitual responses that, after a task switch, had a detrimental impact on task performance. Forming an if-then plan reduced the negative impact of habit on performance. However, the effect of forming implementation intentions was smaller among participants who possessed strong habits as compared to participants who had weaker habits. Experiment 2 provided a field test of the role of habit strength in moderating the relationship between implementation intentions and behaviour in the context of smoking. Implementation intentions reduced smoking among participants with weak or moderate smoking habits, but not among participants with strong smoking habits. In summary, habit strength moderates the effectiveness of if-then plan formation in breaking unwanted habits.

SHERLOC: An investigation for Mars 2020

Science.gov (United States)

Beegle, Luther; Bhartia, Rohit

2016-04-01

SHERLOC is a Deep UV (DUV) native fluorescence and resonance Raman spectrometer that was selected as part of the Mars 2020 payload. It is a robotic arm mounted instrument that utilizes a DUV laser to generate characteristic Raman and fluorescence photons from a targeted spot. The DUV laser is co-boresighted to a context imager and integrated into an autofocusing/scanning optical system that allows us to correlate spectral signatures to surface textures, morphology and visible features. Additionally, it has recently been augmented with an imaging system that is a built-to-print version of the MArs Hand Lens Imager (MAHLI) instrument on the Mars Science Laboratory (MSL). Through the use of an internal scanning mirror, autofocusing lens, and a depth of focus of ±500 μm, the 100 μm laser spot can be systematically scanned over a 7x7 mm area with a fine-scale spatial resolution on natural or abraded surfaces and boreholes to a depth of at least 13 mm, without further arm movement. Through the use of the context imager, SHERLOC's data products can be combined with observations made by other instruments on the Mars 2020 payload. By bringing to bear multiple scientific instruments on a single sample, our ability to assess the habitability of ancient environments and search for potential biosignatures preserved within the geologic record will be greatly enhanced, making possible the selection of high-priority samples for caching. The SHERLOC investigation combines two spectral phenomena, fluorescence and pre-resonance/resonance DUV Raman scattering. These spectral features are resolvable when a high-radiance, narrow line-width, laser source illuminates a sample. In fluorescence, the incident photons are absorbed and re-emitted at a longer wavelength. The difference between the excitation and emission wavelength is the difference between the excitation frequency and the lowest electronic state frequency that increases with increasing aromatic structure (i.e., number of

DECISION MAKING STYLES AND STUDY ORIENTATION

OpenAIRE

Govind, K.; Amalor, D.

2016-01-01

The present study is an attempt to study the relationship of Study Orientation (Study Habits and Attitudes) with decision making styles among higher secondary students. Survey of Study Habits and Attitudes (SSHA) developed by Brown and Holtzman (1967) and Flinders Decision Making Questionnaires I and II (DMQ-I and DMQ-II) developed by Mann (1982) were used to collect data. As large as 148 Higher Secondary Students pursuing the first year study of Higher Secondary Course (HSC) participated in ...

Teaching originality? Common habits behind creative production in science and arts

Directory of Open Access Journals (Sweden)

Marten Scheffer

2017-06-01

Full Text Available Originality is a prerequisite for world-changing science and arts alike, but it cannot be taught. Or can it? Here, we show that a set of habits that are - surprisingly - shared among successful artists and scientists may catalyze creative output. We reveal three groups of such habits, each corresponding to a cluster of personality traits, shown to be shared by creative artists and scientists. The first habit group "embrace the unexpected" corresponds to the character trait "openness to new experiences" and encompasses tendencies to go ahead without a plan, collect diverse experiences, and take risks. The second group "create conditions for creation" links to the personality trait "autonomous" and encompasses simple habits such as making empty time and carrying a notebook. The third class of habits "break away from dogma" links to the shared personality trait "norm doubting" and stands for a strong drive to escape from established systems and also occasionally destroy part of one's own work to break tunnel vision and start anew. Although personality traits are hard to change, the habits we found hint at techniques or skills that may be taught.

A Subjective Assessment of Alternative Mission Architecture Operations Concepts for the Human Exploration of Mars at NASA Using a Three-Dimensional Multi-Criteria Decision Making Model

Science.gov (United States)

Tavana, Madjid

2003-01-01

The primary driver for developing missions to send humans to other planets is to generate significant scientific return. NASA plans human planetary explorations with an acceptable level of risk consistent with other manned operations. Space exploration risks can not be completely eliminated. Therefore, an acceptable level of cost, technical, safety, schedule, and political risks and benefits must be established for exploratory missions. This study uses a three-dimensional multi-criteria decision making model to identify the risks and benefits associated with three alternative mission architecture operations concepts for the human exploration of Mars identified by the Mission Operations Directorate at Johnson Space Center. The three alternatives considered in this study include split, combo lander, and dual scenarios. The model considers the seven phases of the mission including: 1) Earth Vicinity/Departure; 2) Mars Transfer; 3) Mars Arrival; 4) Planetary Surface; 5) Mars Vicinity/Departure; 6) Earth Transfer; and 7) Earth Arrival. Analytic Hierarchy Process (AHP) and subjective probability estimation are used to captures the experts belief concerning the risks and benefits of the three alternative scenarios through a series of sequential, rational, and analytical processes.

Robotics and automation in Mars exploration

Science.gov (United States)

Bourke, Roger D.; Sturms, Francis M., Jr.; Golombek, Matthew P.; Gamber, R. T.

1992-01-01

A new approach to the exploration of Mars is examined which relies on the use of smaller and simpler vehicles. The new strategy involves the following principles: limiting science objectives to retrieval of rock samples from several different but geologically homogeneous areas; making use of emerging microspacecraft technologies to significantly reduce the mass of hardware elements; simplifying missions to the absolutely essential elements; and managing risk through the employment of many identical independent pieces some of which may fail. The emerging technologies and their applications to robotic Mars missions are discussed.

Conventional and Bimodal Nuclear Thermal Rocket (NTR) Artificial Gravity Mars Transfer Vehicle Concepts

Science.gov (United States)

Borowski, Stanley K.; McCurdy, David R.; Packard, Thomas W.

2016-01-01

A variety of countermeasures have been developed to address the debilitating physiological effects of zero-gravity (0-g) experienced by cosmonauts and astronauts during their approximately 0.5 to 1.2 year long stays in low Earth orbit (LEO). Longer interplanetary flights, combined with possible prolonged stays in Mars orbit, could subject crewmembers to up to approximately 2.5 years of weightlessness. In view of known and recently diagnosed problems associated with 0-g, an artificial gravity (AG) spacecraft offers many advantages and may indeed be an enabling technology for human flights to Mars. A number of important human factors must be taken into account in selecting the rotation radius, rotation rate, and orientation of the habitation module or modules. These factors include the gravity gradient effect, radial and tangential Coriolis forces, along with cross-coupled acceleration effects. Artificial gravity Mars transfer vehicle (MTV) concepts are presented that utilize both conventional NTR, as well as, enhanced bimodal nuclear thermal rocket (BNTR) propulsion. The NTR is a proven technology that generates high thrust and has a specific impulse (Isp) capability of approximately 900 s-twice that of today's best chemical rockets. The AG/MTV concepts using conventional Nuclear Thermal Propulsion (NTP) carry twin cylindrical International Space Station (ISS)- type habitation modules with their long axes oriented either perpendicular or parallel to the longitudinal spin axis of the MTV and utilize photovoltaic arrays (PVAs) for spacecraft power. The twin habitat modules are connected to a central operations hub located at the front of the MTV via two pressurized tunnels that provide the rotation radius for the habitat modules. For the BNTR AG/MTV option, each engine has its own closed secondary helium(He)-xenon (Xe) gas loop and Brayton Rotating Unit (BRU) that can generate 10s of kilowatts (kWe) of spacecraft electrical power during the mission coast phase

Water activity and the challenge for life on early Mars.

Science.gov (United States)

Tosca, Nicholas J; Knoll, Andrew H; McLennan, Scott M

2008-05-30

In situ and orbital exploration of the martian surface has shown that acidic, saline liquid water was intermittently available on ancient Mars. The habitability of these waters depends critically on water activity (aH2O), a thermodynamic measure of salinity, which, for terrestrial organisms, has sharply defined limits. Using constraints on fluid chemistry and saline mineralogy based on martian data, we calculated the maximum aH2O for Meridiani Planum and other environments where salts precipitated from martian brines. Our calculations indicate that the salinity of well-documented surface waters often exceeded levels tolerated by known terrestrial organisms.

Artificial Intelligence Support for Landing Site Selection on Mars

Science.gov (United States)

Rongier, G.; Pankratius, V.

2017-12-01

Mars is a key target for planetary exploration; a better understanding of its evolution and habitability requires roving in situ. Landing site selection is becoming more challenging for scientists as new instruments generate higher data volumes. The involved engineering and scientific constraints make site selection and the anticipation of possible onsite actions into a complex optimization problem: there may be multiple acceptable solutions depending on various goals and assumptions. Solutions must also account for missing data, errors, and potential biases. To address these problems, we propose an AI-informed decision support system that allows scientists, mission designers, engineers, and committees to explore alternative site selection choices based on data. In particular, we demonstrate first results of an exploratory case study using fuzzy logic and a simulation of a rover's mobility map based on the fast marching algorithm. Our system computes favorability maps of the entire planet to facilitate landing site selection and allows a definition of different configurations for rovers, science target priorities, landing ellipses, and other constraints. For a rover similar to NASA's Mars 2020 rover, we present results in form of a site favorability map as well as four derived exploration scenarios that depend on different prioritized scientific targets, all visualizing inherent tradeoffs. Our method uses the NASA PDS Geosciences Node and the NASA/ICA Integrated Database of Planetary Features. Under common assumptions, the data products reveal Eastern Margaritifer Terra and Meridiani Planum to be the most favorable sites due to a high concentration of scientific targets and a flat, easily navigable surface. Our method also allows mission designers to investigate which constraints have the highest impact on the mission exploration potential and to change parameter ranges. Increasing the elevation limit for landing, for example, provides access to many additional

Wet Mars, Dry Mars

Science.gov (United States)

Fillingim, M. O.; Brain, D. A.; Peticolas, L. M.; Yan, D.; Fricke, K. W.; Thrall, L.

2012-12-01

The magnetic fields of the large terrestrial planets, Venus, Earth, and Mars, are all vastly different from each other. These differences can tell us a lot about the interior structure, interior history, and even give us clues to the atmospheric history of these planets. This poster highlights the third in a series of presentations that target school-age audiences with the overall goal of helping the audience visualize planetary magnetic field and understand how they can impact the climatic evolution of a planet. Our first presentation, "Goldilocks and the Three Planets," targeted to elementary school age audiences, focuses on the differences in the atmospheres of Venus, Earth, and Mars and the causes of the differences. The second presentation, "Lost on Mars (and Venus)," geared toward a middle school age audience, highlights the differences in the magnetic fields of these planets and what we can learn from these differences. Finally, in the third presentation, "Wet Mars, Dry Mars," targeted to high school age audiences and the focus of this poster, the emphasis is on the long term climatic affects of the presence or absence of a magnetic field using the contrasts between Earth and Mars. These presentations are given using visually engaging spherical displays in conjunction with hands-on activities and scientifically accurate 3D models of planetary magnetic fields. We will summarize the content of our presentations, discuss our lessons learned from evaluations, and show (pictures of) our hands-on activities and 3D models.

Evidence for indigenous nitrogen in sedimentary and aeolian deposits from the Curiosity rover investigations at Gale crater, Mars

Science.gov (United States)

Stern, Jennifer C.; Sutter, Brad; Freissinet, Caroline; Navarro-González, Rafael; McKay, Christopher P.; Archer, P. Douglas; Buch, Arnaud; Brunner, Anna E.; Coll, Patrice; Eigenbrode, Jennifer L.; Fairen, Alberto G.; Franz, Heather B.; Glavin, Daniel P.; Kashyap, Srishti; McAdam, Amy C.; Ming, Douglas W.; Steele, Andrew; Szopa, Cyril; Wray, James J.; Martín-Torres, F. Javier; Zorzano, Maria-Paz; Conrad, Pamela G.; Mahaffy, Paul R.; Kemppinen, Osku; Bridges, Nathan; Johnson, Jeffrey R.; Minitti, Michelle; Cremers, David; Bell, James F.; Edgar, Lauren; Farmer, Jack; Godber, Austin; Wadhwa, Meenakshi; Wellington, Danika; McEwan, Ian; Newman, Claire; Richardson, Mark; Charpentier, Antoine; Peret, Laurent; King, Penelope; Blank, Jennifer; Weigle, Gerald; Schmidt, Mariek; Li, Shuai; Milliken, Ralph; Robertson, Kevin; Sun, Vivian; Baker, Michael; Edwards, Christopher; Ehlmann, Bethany; Farley, Kenneth; Griffes, Jennifer; Grotzinger, John; Miller, Hayden; Newcombe, Megan; Pilorget, Cedric; Rice, Melissa; Siebach, Kirsten; Stack, Katie; Stolper, Edward; Brunet, Claude; Hipkin, Victoria; Léveillé, Richard; Marchand, Geneviève; Sánchez, Pablo Sobrón; Favot, Laurent; Cody, George; Steele, Andrew; Flückiger, Lorenzo; Lees, David; Nefian, Ara; Martin, Mildred; Gailhanou, Marc; Westall, Frances; Israël, Guy; Agard, Christophe; Baroukh, Julien; Donny, Christophe; Gaboriaud, Alain; Guillemot, Philippe; Lafaille, Vivian; Lorigny, Eric; Paillet, Alexis; Pérez, René; Saccoccio, Muriel; Yana, Charles; Armiens-Aparicio, Carlos; Rodríguez, Javier Caride; Blázquez, Isaías Carrasco; Gómez, Felipe Gómez; Gómez-Elvira, Javier; Hettrich, Sebastian; Malvitte, Alain Lepinette; Jiménez, Mercedes Marín; Martínez-Frías, Jesús; Martín-Soler, Javier; - Torres, F. Javier Martín; Jurado, Antonio Molina; Mora-Sotomayor, Luis; Caro, Guillermo Muñoz; López, Sara Navarro; Peinado-González, Verónica; Pla-García, Jorge; Manfredi, José Antonio Rodriguez; Romeral-Planelló, Julio José; Fuentes, Sara Alejandra Sans; Martinez, Eduardo Sebastian; Redondo, Josefina Torres; Urqui-O'Callaghan, Roser; Mier, María-Paz Zorzano; Chipera, Steve; Lacour, Jean-Luc; Mauchien, Patrick; Sirven, Jean-Baptiste; Manning, Heidi; Fairén, Alberto; Hayes, Alexander; Joseph, Jonathan; Squyres, Steven; Sullivan, Robert; Thomas, Peter; Dupont, Audrey; Lundberg, Angela; Melikechi, Noureddine; Mezzacappa, Alissa; DeMarines, Julia; Grinspoon, David; Reitz, Günther; Prats, Benito; Atlaskin, Evgeny; Genzer, Maria; Harri, Ari-Matti; Haukka, Harri; Kahanpää, Henrik; Kauhanen, Janne; Kemppinen, Osku; Paton, Mark; Polkko, Jouni; Schmidt, Walter; Siili, Tero; Fabre, Cécile; Wray, James; Wilhelm, Mary Beth; Poitrasson, Franck; Patel, Kiran; Gorevan, Stephen; Indyk, Stephen; Paulsen, Gale; Gupta, Sanjeev; Bish, David; Schieber, Juergen; Gondet, Brigitte; Langevin, Yves; Geffroy, Claude; Baratoux, David; Berger, Gilles; Cros, Alain; d’Uston, Claude; Forni, Olivier; Gasnault, Olivier; Lasue, Jérémie; Lee, Qiu-Mei; Maurice, Sylvestre; Meslin, Pierre-Yves; Pallier, Etienne; Parot, Yann; Pinet, Patrick; Schröder, Susanne; Toplis, Mike; Lewin, Éric; Brunner, Will; Heydari, Ezat; Achilles, Cherie; Oehler, Dorothy; Sutter, Brad; Cabane, Michel; Coscia, David; Israël, Guy; Szopa, Cyril; Dromart, Gilles; Robert, François; Sautter, Violaine; Le Mouélic, Stéphane; Mangold, Nicolas; Nachon, Marion; Buch, Arnaud; Stalport, Fabien; Coll, Patrice; François, Pascaline; Raulin, François; Teinturier, Samuel; Cameron, James; Clegg, Sam; Cousin, Agnès; DeLapp, Dorothea; Dingler, Robert; Jackson, Ryan Steele; Johnstone, Stephen; Lanza, Nina; Little, Cynthia; Nelson, Tony; Wiens, Roger C.; Williams, Richard B.; Jones, Andrea; Kirkland, Laurel; Treiman, Allan; Baker, Burt; Cantor, Bruce; Caplinger, Michael; Davis, Scott; Duston, Brian; Edgett, Kenneth; Fay, Donald; Hardgrove, Craig; Harker, David; Herrera, Paul; Jensen, Elsa; Kennedy, Megan R.; Krezoski, Gillian; Krysak, Daniel; Lipkaman, Leslie; Malin, Michael; McCartney, Elaina; McNair, Sean; Nixon, Brian; Posiolova, Liliya; Ravine, Michael; Salamon, Andrew; Saper, Lee; Stoiber, Kevin; Supulver, Kimberley; Van Beek, Jason; Van Beek, Tessa; Zimdar, Robert; French, Katherine Louise; Iagnemma, Karl; Miller, Kristen; Summons, Roger; Goesmann, Fred; Goetz, Walter; Hviid, Stubbe; Johnson, Micah; Lefavor, Matthew; Lyness, Eric; Breves, Elly; Dyar, M. Darby; Fassett, Caleb; Blake, David F.; Bristow, Thomas; DesMarais, David; Edwards, Laurence; Haberle, Robert; Hoehler, Tori; Hollingsworth, Jeff; Kahre, Melinda; Keely, Leslie; McKay, Christopher; Wilhelm, Mary Beth; Bleacher, Lora; Brinckerhoff, William; Choi, David; Conrad, Pamela; Dworkin, Jason P.; Eigenbrode, Jennifer; Floyd, Melissa; Freissinet, Caroline; Garvin, James; Glavin, Daniel; Harpold, Daniel; Jones, Andrea; Mahaffy, Paul; Martin, David K.; McAdam, Amy; Pavlov, Alexander; Raaen, Eric; Smith, Michael D.; Stern, Jennifer; Tan, Florence; Trainer, Melissa; Meyer, Michael; Posner, Arik; Voytek, Mary; Anderson, Robert C; Aubrey, Andrew; Beegle, Luther W.; Behar, Alberto; Blaney, Diana; Brinza, David; Calef, Fred; Christensen, Lance; Crisp, Joy A.; DeFlores, Lauren; Ehlmann, Bethany; Feldman, Jason; Feldman, Sabrina; Flesch, Gregory; Hurowitz, Joel; Jun, Insoo; Keymeulen, Didier; Maki, Justin; Mischna, Michael; Morookian, John Michael; Parker, Timothy; Pavri, Betina; Schoppers, Marcel; Sengstacken, Aaron; Simmonds, John J.; Spanovich, Nicole; Juarez, Manuel de la Torre; Vasavada, Ashwin R.; Webster, Christopher R.; Yen, Albert; Archer, Paul Douglas; Cucinotta, Francis; Jones, John H.; Ming, Douglas; Morris, Richard V.; Niles, Paul; Rampe, Elizabeth; Nolan, Thomas; Fisk, Martin; Radziemski, Leon; Barraclough, Bruce; Bender, Steve; Berman, Daniel; Dobrea, Eldar Noe; Tokar, Robert; Vaniman, David; Williams, Rebecca M. E.; Yingst, Aileen; Lewis, Kevin; Leshin, Laurie; Cleghorn, Timothy; Huntress, Wesley; Manhès, Gérard; Hudgins, Judy; Olson, Timothy; Stewart, Noel; Sarrazin, Philippe; Grant, John; Vicenzi, Edward; Wilson, Sharon A.; Bullock, Mark; Ehresmann, Bent; Hamilton, Victoria; Hassler, Donald; Peterson, Joseph; Rafkin, Scot; Zeitlin, Cary; Fedosov, Fedor; Golovin, Dmitry; Karpushkina, Natalya; Kozyrev, Alexander; Litvak, Maxim; Malakhov, Alexey; Mitrofanov, Igor; Mokrousov, Maxim; Nikiforov, Sergey; Prokhorov, Vasily; Sanin, Anton; Tretyakov, Vladislav; Varenikov, Alexey; Vostrukhin, Andrey; Kuzmin, Ruslan; Clark, Benton; Wolff, Michael; McLennan, Scott; Botta, Oliver; Drake, Darrell; Bean, Keri; Lemmon, Mark; Schwenzer, Susanne P.; Anderson, Ryan B.; Herkenhoff, Kenneth; Lee, Ella Mae; Sucharski, Robert; Hernández, Miguel Ángel de Pablo; Ávalos, Juan José Blanco; Ramos, Miguel; Kim, Myung-Hee; Malespin, Charles; Plante, Ianik; Muller, Jan-Peter; Navarro-González, Rafael; Ewing, Ryan; Boynton, William; Downs, Robert; Fitzgibbon, Mike; Harshman, Karl; Morrison, Shaunna; Dietrich, William; Kortmann, Onno; Palucis, Marisa; Sumner, Dawn Y.; Williams, Amy; Lugmair, Günter; Wilson, Michael A.; Rubin, David; Jakosky, Bruce; Balic-Zunic, Tonci; Frydenvang, Jens; Jensen, Jaqueline Kløvgaard; Kinch, Kjartan; Koefoed, Asmus; Madsen, Morten Bo; Stipp, Susan Louise Svane; Boyd, Nick; Campbell, John L.; Gellert, Ralf; Perrett, Glynis; Pradler, Irina; VanBommel, Scott; Jacob, Samantha; Owen, Tobias; Rowland, Scott; Atlaskin, Evgeny; Savijärvi, Hannu; Boehm, Eckart; Böttcher, Stephan; Burmeister, Sönke; Guo, Jingnan; Köhler, Jan; García, César Martín; Mueller-Mellin, Reinhold; Wimmer-Schweingruber, Robert; Bridges, John C.; McConnochie, Timothy; Benna, Mehdi; Franz, Heather; Bower, Hannah; Brunner, Anna; Blau, Hannah; Boucher, Thomas; Carmosino, Marco; Atreya, Sushil; Elliott, Harvey; Halleaux, Douglas; Rennó, Nilton; Wong, Michael; Pepin, Robert; Elliott, Beverley; Spray, John; Thompson, Lucy; Gordon, Suzanne; Newsom, Horton; Ollila, Ann; Williams, Joshua; Vasconcelos, Paulo; Bentz, Jennifer; Nealson, Kenneth; Popa, Radu; Kah, Linda C.; Moersch, Jeffrey; Tate, Christopher; Day, Mackenzie; Kocurek, Gary; Hallet, Bernard; Sletten, Ronald; Francis, Raymond; McCullough, Emily; Cloutis, Ed; ten Kate, Inge Loes; Kuzmin, Ruslan; Arvidson, Raymond; Fraeman, Abigail; Scholes, Daniel; Slavney, Susan; Stein, Thomas; Ward, Jennifer; Berger, Jeffrey; Moores, John E.

2015-01-01

The Sample Analysis at Mars (SAM) investigation on the Mars Science Laboratory (MSL) Curiosity rover has detected oxidized nitrogen-bearing compounds during pyrolysis of scooped aeolian sediments and drilled sedimentary deposits within Gale crater. Total N concentrations ranged from 20 to 250 nmol N per sample. After subtraction of known N sources in SAM, our results support the equivalent of 110–300 ppm of nitrate in the Rocknest (RN) aeolian samples, and 70–260 and 330–1,100 ppm nitrate in John Klein (JK) and Cumberland (CB) mudstone deposits, respectively. Discovery of indigenous martian nitrogen in Mars surface materials has important implications for habitability and, specifically, for the potential evolution of a nitrogen cycle at some point in martian history. The detection of nitrate in both wind-drifted fines (RN) and in mudstone (JK, CB) is likely a result of N2 fixation to nitrate generated by thermal shock from impact or volcanic plume lightning on ancient Mars. Fixed nitrogen could have facilitated the development of a primitive nitrogen cycle on the surface of ancient Mars, potentially providing a biochemically accessible source of nitrogen. PMID:25831544

Evidence for indigenous nitrogen in sedimentary and aeolian deposits from the Curiosity rover investigations at Gale crater, Mars.

Science.gov (United States)

Stern, Jennifer C; Sutter, Brad; Freissinet, Caroline; Navarro-González, Rafael; McKay, Christopher P; Archer, P Douglas; Buch, Arnaud; Brunner, Anna E; Coll, Patrice; Eigenbrode, Jennifer L; Fairen, Alberto G; Franz, Heather B; Glavin, Daniel P; Kashyap, Srishti; McAdam, Amy C; Ming, Douglas W; Steele, Andrew; Szopa, Cyril; Wray, James J; Martín-Torres, F Javier; Zorzano, Maria-Paz; Conrad, Pamela G; Mahaffy, Paul R

2015-04-07

The Sample Analysis at Mars (SAM) investigation on the Mars Science Laboratory (MSL) Curiosity rover has detected oxidized nitrogen-bearing compounds during pyrolysis of scooped aeolian sediments and drilled sedimentary deposits within Gale crater. Total N concentrations ranged from 20 to 250 nmol N per sample. After subtraction of known N sources in SAM, our results support the equivalent of 110-300 ppm of nitrate in the Rocknest (RN) aeolian samples, and 70-260 and 330-1,100 ppm nitrate in John Klein (JK) and Cumberland (CB) mudstone deposits, respectively. Discovery of indigenous martian nitrogen in Mars surface materials has important implications for habitability and, specifically, for the potential evolution of a nitrogen cycle at some point in martian history. The detection of nitrate in both wind-drifted fines (RN) and in mudstone (JK, CB) is likely a result of N2 fixation to nitrate generated by thermal shock from impact or volcanic plume lightning on ancient Mars. Fixed nitrogen could have facilitated the development of a primitive nitrogen cycle on the surface of ancient Mars, potentially providing a biochemically accessible source of nitrogen.

Plume Mitigation for Mars Terminal Landing: Soil Stabilization Project

Science.gov (United States)

Hintze, Paul E.

2014-01-01

Kennedy Space Center (KSC) has led the efforts for lunar and Martian landing site preparation, including excavation, soil stabilization, and plume damage prediction. There has been much discussion of sintering but until our team recently demonstrated it for the lunar case there was little understanding of the serious challenges. Simplistic sintering creates a crumbly, brittle, weak surface unsuitable for a rocket exhaust plume. The goal of this project is to solve those problems and make it possible to land a human class lander on Mars, making terminal landing of humans on Mars possible for the first time.

The power of habits: unhealthy snacking behaviour is primarily predicted by habit strength.

Science.gov (United States)

Verhoeven, Aukje A C; Adriaanse, Marieke A; Evers, Catharine; de Ridder, Denise T D

2012-11-01

Although increasing evidence shows the importance of habits in explaining health behaviour, many studies still rely solely on predictors that emphasize the role of conscious intentions. The present study was designed to test the importance of habit strength in explaining unhealthy snacking behaviour in a large representative community sample (N= 1,103). To test our hypothesis that habits are crucial when explaining unhealthy snacking behaviour, their role was compared to the 'Power of Food', a related construct that addresses sensitivity to food cues in the environment. Moreover, the relation between Power of Food and unhealthy snacking habits was assessed. A prospective design was used to determine the impact of habits in relation to intention, Power of Food and a number of demographic variables. One month after filling out the questionnaire, including measures of habit strength and Power of Food, participants reported their unhealthy snacking behaviour by means of a 7-day snack diary. Results showed that habit strength was the most important predictor, outperforming all other variables in explaining unhealthy snack intake. The findings demonstrate that snacking habits provide a unique contribution in explaining unhealthy snacking behaviour, stressing the importance of addressing habit strength in further research and interventions concerning unhealthy snacking behaviour. ©2012 The British Psychological Society.

Austere Human Missions to Mars

Science.gov (United States)

Price, Hoppy; Hawkins, Alisa M.; Tadcliffe, Torrey O.

2009-01-01

preposition a habitat, supplies, and exploration equipment. The next opportunity, two years later, would send to Mars orbit 1) a lander with a Mars Ascent Vehicle (MAV) and 2) a crewed Mars Transit Habitat with an Orion CEV for Earth return. The following opportunity, two years after the first crew, would go back to cargo-only launches. This alternation of cargo and crew opportunities results in a sustainable launch rate of six Ares V launches every two years. It is notable that four of the six launches per Mars opportunity are identical, build-to-print, Tran-Mars Injection stages. This type of production rate could lend itself well to a COTStype service provider, and would make it feasible to have a live spare in place in the event of a single launch failure.

Bringing a Chemical Laboratory Named Sam to Mars on the 2011 Curiosity Rover

Science.gov (United States)

Mahaffy, P. R.; Bleacher, L.; Jones, A.; Atreya, S. K.; Manning, H. L.; Cabane, M.; Webster, C. R.; Sam Team

2010-12-01

Introduction: An important goal of upcoming missions to Mars is to understand if life could have developed there. The task of the Sample Analysis at Mars (SAM) suite of instruments [1] and the other Curiosity investigations [2] is to move us steadily toward that goal with an assessment of the habitability of our neighboring planet through a series of chemical and geological measurements. SAM is designed to search for organic compounds and inorganic volatiles and measure isotope ratios. Other instruments on Curiosity will provide elemental analysis and identify minerals. SAM will analyze both atmospheric samples and gases evolved from powdered rocks that may have formed billions of years ago with Curiosity providing access to interesting sites scouted by orbiting cameras and spectrometers. SAM Instrument Suite: SAM’s instruments are a Quadrupole Mass Spectrometer (QMS), a 6-column Gas Chromatograph (GC), and a 2-channel Tunable Laser Spectrometer (TLS). SAM can identify organic compounds in Mars rocks to sub-ppb sensitivity and secure precise isotope ratios for C, H, and O in carbon dioxide and water and measure trace levels of methane and its carbon 13 isotope. The SAM gas processing system consists of valves, heaters, pressure sensors, gas scrubbers and getters, traps, and gas tanks used for calibration or combustion experiments [2]. A variety of calibrant compounds interior and exterior to SAM will allow the science and engineering teams to assess SAM’s performance. SAM has been calibrated and tested in a Mars-like environment. Keeping Educators and the Public Informed: The Education and Public Outreach (EPO) goals of the SAM team are to make this complex chemical laboratory and its data widely available to educators, students, and the public. Formal education activities include developing templates for professional development workshops for educators to teach them about SAM and Curiosity, incorporating data into Mars Student Data Teams, and writing articles

Habitable Zones in the Universe

OpenAIRE

Gonzalez, G.

2005-01-01

Habitability varies dramatically with location and time in the universe. This was recognized centuries ago, but it was only in the last few decades that astronomers began to systematize the study of habitability. The introduction of the concept of the habitable zone was key to progress in this area. The habitable zone concept was first applied to the space around a star, now called the Circumstellar Habitable Zone. Recently, other, vastly broader, habitable zones have been proposed. We review...

NASA Mars Conference

International Nuclear Information System (INIS)

Reiber, D.B.

1988-01-01

Papers about Mars and Mars exploration are presented, covering topics such as Martian history, geology, volcanism, channels, moons, atmosphere, meteorology, water on the planet, and the possibility of life. The unmanned exploration of Mars is discussed, including the Phobos Mission, the Mars Observer, the Mars Aeronomy Observer, the seismic network, Mars sample return missions, and the Mars Ball, an inflatable-sectored-tire rover concept. Issues dealing with manned exploration of Mars are examined, such as the reasons for exploring Mars, mission scenarios, a transportation system for routine visits, technologies for Mars expeditions, the human factors for Mars missions, life support systems, living and working on Mars, and the report of the National Commission on Space

Investigation of Correlation between Personality Traits and Dietary Habits in Female Students

Directory of Open Access Journals (Sweden)

Najmeh Golestanbagh

2016-06-01

Full Text Available Background and Objectives: Proper nutrition has a significant role in prevention of chronic disease and health promotion. Psychological factors play an important role in making food choices and subsequently dietary habits and in this context, personality is considered as a key factor. The present study was performed with the purpose of determining the correlation between personality traits and dietary habits in female students. Methods: The present research was conducted as a descriptive-correlational study on 224 female students aged 18-30 years in Ahvaz Jundishapur University of Medical Sciences (2013-2014. Personality traits (neuroticism, extraversion, openness to experience, agreeableness, and conscientiousness were assessed using NEO Five-Factor Inventory and dietary habits were were assessed by a dietary habits questionnaire containing 20 questions about dietary habits. Data were analyzed using Pearson's correlation coefficient and stepwise regression test. The significance level was considered to be p<0.05. Results: In this study, high neuroticism and openness were correlated with low score of dietary habits (p<0.01. Higher level of conscientiousness was significantly correlated with high score of dietary habits (p<0.01. Based on the stepwise regression analysis, personality traits can predict the score of dietary habits (p<0.01. Conclusion: The results of this study revealed that neuroticism and openness are correlated with unhealthy dietary habits, and conscientiousness is correlated with healthy dietary habits. Therefore, appropriate nutritional educations based on the personality traits of students are recommended to modify dietary patterns and prevent chronic diseases.

On the Habitability of Aquaplanets

OpenAIRE

Rolando Cardenas; Noel Perez; Jesus Martinez-Frias; Osmel Martin

2014-01-01

An Aquatic Habitability Index is proposed, based on Quantitative Habitability Theory, and considering a very general model for life. It is a primary habitability index, measuring habitability for phytoplankton in the first place. The index is applied to some case studies, such as the habitability changes in Earth due to environmental perturbations caused by asteroid impacts.

On the Habitability of Aquaplanets

Directory of Open Access Journals (Sweden)

Rolando Cardenas

2014-08-01

Full Text Available An Aquatic Habitability Index is proposed, based on Quantitative Habitability Theory, and considering a very general model for life. It is a primary habitability index, measuring habitability for phytoplankton in the first place. The index is applied to some case studies, such as the habitability changes in Earth due to environmental perturbations caused by asteroid impacts.

The Topography of Mars: Understanding the Surface of Mars Through the Mars Orbiter Laser Altimeter

Science.gov (United States)

Derby, C. A.; Neumann, G. A.; Sakimoto, S. E.

2001-12-01

The Mars Orbiter Laser Altimeter has been orbiting Mars since 1997 and has measured the topography of Mars with a meter of vertical accuracy. This new information has improved our understanding of both the surface and the interior of Mars. The topographic globe and the labeled topographic map of Mars illustrate these new data in a format that can be used in a classroom setting. The map is color shaded to show differences in elevation on Mars, presenting Mars with a different perspective than traditional geological and geographic maps. Through the differences in color, students can see Mars as a three-dimensional surface and will be able to recognize features that are invisible in imagery. The accompanying lesson plans are designed for middle school science students and can be used both to teach information about Mars as a planet and Mars in comparison to Earth, fitting both the solar system unit and the Earth science unit in a middle school curriculum. The lessons are referenced to the National Benchmark standards for students in grades 6-8 and cover topics such as Mars exploration, the Mars Orbiter Laser Altimeter, resolution and powers of 10, gravity, craters, seismic waves and the interior structure of a planet, isostasy, and volcanoes. Each lesson is written in the 5 E format and includes a student content activity and an extension showing current applications of Mars and MOLA data. These activities can be found at http://ltpwww.gsfc.nasa.gov/education/resources.html. Funding for this project was provided by the Maryland Space Grant Consortium and the MOLA Science Team, Goddard Space Flight Center.

Planetary Habitability and Rapid Environmental Change: The Biological Perspective

Science.gov (United States)

Schulze-Makuch, D.; Fairen, A.; Irwin, L.

2012-12-01

Environmental conditions can change drastically and rapidly during the natural history of a planetary body. We have detailed evidence of these dramatic events from Venus, Earth, Mars, and Titan. Most of these occurrences seem to be triggered by astronomical events such as asteroid impacts or supernova explosions; others are triggered by the planet or moon itself (e.g., supervolcano eruptions). The associated question is always how these events affect the habitability of a planet, particularly the origin and presence of life. Under what conditions would such a drastic event be so catastrophic that it would prohibit the origin of life or be so devastating to existing organisms, that life would not be able to recover and be all but extinguished from a planet? Under what conditions would such an event be positive for the evolution of life, for example spurring life via mass extinctions and associated vacant habitats to the invention of new body plans and higher complexity? Here, we provide insights of what we can learn from the natural history of our own planet, which experienced many environmental disasters and abrupt climate changes, from the impact event that created the Moon to the extinction of the dinosaurs. We apply these insights to other planetary bodies and the question about the presence of life. One example is Mars, which underwent drastic environmental changes at the end of the Noachian period. Assuming that microbial life became established on Mars, could it have survived, perhaps by retreating to environmental niches? Life just starting out would have certainly been more vulnerable to extinction. But how far would it have to have evolved to be more resistant to potential extinction events? Would it have to be global in distribution to survive? Another example is Venus. Should Venus be seen as an example where life, which possibly arose in the first few hundred million years when the planet was still in the habitable zone, would have had no chance to

Investigation of Correlation between Personality Traits and Dietary Habits in Female Students

OpenAIRE

Najmeh Golestanbagh; Reza Amani; Sorour Neamatpour; Mohammad Hossein Haghighizadeh

2016-01-01

Background and Objectives: Proper nutrition has a significant role in prevention of chronic disease and health promotion. Psychological factors play an important role in making food choices and subsequently dietary habits and in this context, personality is considered as a key factor. The present study was performed with the purpose of determining the correlation between personality traits and dietary habits in female students. Methods: The present research was conducted as a descriptiv...

Mars Surveyor Program '01 Mars Environmental Compatibility Assessment wet chemistry lab: a sensor array for chemical analysis of the Martian soil

Science.gov (United States)

Kounaves, Samuel P.; Lukow, Stefan R.; Comeau, Brian P.; Hecht, Michael H.; Grannan-Feldman, Sabrina M.; Manatt, Ken; West, Steven J.; Wen, Xiaowen; Frant, Martin; Gillette, Tim

2003-01-01

The Mars Environmental Compatibility Assessment (MECA) instrument was designed, built, and flight qualified for the now canceled MSP (Mars Surveyor Program) '01 Lander. The MECA package consisted of a microscope, electrometer, material patch plates, and a wet chemistry laboratory (WCL). The primary goal of MECA was to analyze the Martian soil (regolith) for possible hazards to future astronauts and to provide a better understanding of Martian regolith geochemistry. The purpose of the WCL was to analyze for a range of soluble ionic chemical species and electrochemical parameters. The heart of the WCL was a sensor array of electrochemically based ion-selective electrodes (ISE). After 20 months storage at -23 degrees C and subsequent extended freeze/thawing cycles, WCL sensors were evaluated to determine both their physical durability and analytical responses. A fractional factorial calibration of the sensors was used to obtain slope, intercept, and all necessary selectivity coefficients simultaneously for selected ISEs. This calibration was used to model five cation and three anion sensors. These data were subsequently used to determine concentrations of several ions in two soil leachate simulants (based on terrestrial seawater and hypothesized Mars brine) and four actual soil samples. The WCL results were compared to simulant and soil samples using ion chromatography and inductively coupled plasma optical emission spectroscopy. The results showed that flight qualification and prolonged low-temperature storage conditions had minimal effects on the sensors. In addition, the analytical optimization method provided quantitative and qualitative data that could be used to accurately identify the chemical composition of the simulants and soils. The WCL has the ability to provide data that can be used to "read" the chemical, geological, and climatic history of Mars, as well as the potential habitability of its regolith.

Assessment of reading habits of national open university of Nigeria ...

African Journals Online (AJOL)

Assessment of reading habits of national open university of Nigeria students in Abuja. ... A general recommendation was made to the ministry of education in Nigeria to make reading a subject of its own which ... AJOL African Journals Online.

Effects of Mars Regolith Analogs, UVC radiation, Temperature, Pressure, and pH on the Growth and Survivability of Methanogenic Archaea and Stable Carbon Isotope Fractionation: Implications for Surface and Subsurface Life on Mars

Science.gov (United States)

Sinha, Navita

Mars is one of the suitable bodies in our solar system that can accommodate extraterrestrial life. The detection of plumes of methane in the Martian atmosphere, geochemical evidence, indication of flow of intermittent liquid water on the Martian surface, and geomorphologies of Mars have bolstered the plausibility of finding extant or evidence of extinct life on its surface and/or subsurface. However, contemporary Mars has been considered as an inhospitable planet for several reasons, such as low atmospheric surface pressure, low surface temperature, and intense DNA damaging radiation. Despite the hostile conditions of Mars, a few strains of methanogenic archaea have shown survivability in limited surface and subsurface conditions of Mars. Methanogens, which are chemolithoautotrophic non-photosynthetic anaerobic archaea, have been considered ideal models for possible Martian life forms for a long time. The search for biosignatures in the Martian atmosphere and possibility of life on the Martian surface under UVC radiation and deep subsurface under high pressure, temperature, and various pHs are the motivations of this research. Analogous to Earth, Martian atmospheric methane could be biological in origin. Chapter 1 provides relevant information about Mars' habitability, methane on Mars, and different strains of methanogens used in this study. Chapter 2 describes the interpretation of the carbon isotopic data of biogenic methane produced by methanogens grown on various Mars analogs and the results provide clues to determine ambiguous sources of methane on Mars. Chapter 3 illustrates the sensitivity of hydrated and desiccated cultures of halophilic and non-halophilic methanogens to DNA-damaging ultraviolet radiations, and the results imply that UVC radiation may not be an enormous constraint for methanogenic life forms on the surface of Mars. Chapters 4, 5, and 6 discuss the data for the survivability, growth, and morphology of methanogens in presumed deep subsurface

Aeolian sedimentary processes at the Bagnold Dunes, Mars: Implications for modern dune dynamics and sedimentary structures in the aeolian stratigraphic record of Mars

Science.gov (United States)

Ewing, Ryan C.; Bridges, Nathan T.; Sullivan, Rob; Lapotre, Mathieu G. A.; Fischer, Woodward W.; Lamb, Mike P.; Rubin, David M.; Lewis, Kevin W.; Gupta, Sanjeev

2016-04-01

Wind-blown sand dunes are ubiquitous on the surface of Mars and are a recognized component of the martian stratigraphic record. Our current knowledge of the aeolian sedimentary processes that determine dune morphology, drive dune dynamics, and create aeolian cross-stratification are based upon orbital studies of ripple and dune morphodynamics, rover observations of stratification on Mars, Earth analogs, and experimental and theoretical studies of sand movement under Martian conditions. In-situ observations of sand dunes (informally called the Bagnold Dunes) by Curiosity Rover in Gale Crater, Mars provide the first opportunity to make observations of dunes from the grain-to-dune scale thereby filling the gap in knowledge between theory and orbital observations and refining our understanding of the martian aeolian stratigraphic record. We use the suite of cameras on Curiosity, including Navigation Camera (Navcam), Mast Camera (Mastcam) and Mars Hand Lens Imager (MAHLI), to make observations of the Bagnold Dunes. Measurements of sedimentary structures are made where stereo images are available. Observations indicate that structures generated by gravity-driven processes on the dune lee slopes, such as grainflow and grainfall, are similar to the suite of aeolian sedimentary structures observed on Earth and should be present and recognizable in Mars' aeolian stratigraphic record. Structures formed by traction-driven processes deviate significantly from those found on Earth. The dune hosts centimeter-scale wind ripples and large, meter-scale ripples, which are not found on Earth. The large ripples migrate across the depositional, lee slopes of the dune, which implies that these structures should be present in Mars' stratigraphic record and may appear similar to compound-dune stratification.The Mars Science Laboratory Curiosity Rover Team is acknowledged for their support of this work.

Cellular Responses of the Lichen Circinaria gyrosa in Mars-Like Conditions

Directory of Open Access Journals (Sweden)

Rosa de la Torre Noetzel

2018-03-01

differences could be detected and used as markers of the UV-induced damage to the lichen membranes. Based on its viability responses after rehydration, our study shows that the test lichen survived the 30-day incubation in the Mars chamber particularly under niche conditions. However, the photobiont was not able to photosynthesize under the Mars-like conditions, which indicates that the surface of Mars is not a habitable place for C. gyrosa.

Cellular Responses of the Lichen Circinaria gyrosa in Mars-Like Conditions.

Science.gov (United States)

de la Torre Noetzel, Rosa; Miller, Ana Z; de la Rosa, José M; Pacelli, Claudia; Onofri, Silvano; García Sancho, Leopoldo; Cubero, Beatriz; Lorek, Andreas; Wolter, David; de Vera, Jean P

2018-01-01

detected and used as markers of the UV-induced damage to the lichen membranes. Based on its viability responses after rehydration, our study shows that the test lichen survived the 30-day incubation in the Mars chamber particularly under niche conditions. However, the photobiont was not able to photosynthesize under the Mars-like conditions, which indicates that the surface of Mars is not a habitable place for C . gyrosa .

Advanced Communication and Networking Technologies for Mars Exploration

Science.gov (United States)

Bhasin, Kul; Hayden, Jeff; Agre, Jonathan R.; Clare, Loren P.; Yan, Tsun-Yee

2001-01-01

Next-generation Mars communications networks will provide communications and navigation services to a wide variety of Mars science vehicles including: spacecraft that are arriving at Mars, spacecraft that are entering and descending in the Mars atmosphere, scientific orbiter spacecraft, spacecraft that return Mars samples to Earth, landers, rovers, aerobots, airplanes, and sensing pods. In the current architecture plans, the communication services will be provided using capabilities deployed on the science vehicles as well as dedicated communication satellites that will together make up the Mars network. This network will evolve as additional vehicles arrive, depart or end their useful missions. Cost savings and increased reliability will result from the ability to share communication services between missions. This paper discusses the basic architecture that is needed to support the Mars Communications Network part of NASA's Space Science Enterprise (SSE) communications architecture. The network may use various networking technologies such as those employed in the terrestrial Internet, as well as special purpose deep-space protocols to move data and commands autonomously between vehicles, at disparate Mars vicinity sites (on the surface or in near-Mars space) and between Mars vehicles and earthbound users. The architecture of the spacecraft on-board local communications is being reconsidered in light of these new networking requirements. The trend towards increasingly autonomous operation of the spacecraft is aimed at reducing the dependence on resource scheduling provided by Earth-based operators and increasing system fault tolerance. However, these benefits will result in increased communication and software development requirements. As a result, the envisioned Mars communications infrastructure requires both hardware and protocol technology advancements. This paper will describe a number of the critical technology needs and some of the ongoing research

A Blur track on Mars: how do you top that?

CERN Multimedia

Cooke, Rachel

2003-01-01

"On the eve of the landing of the Beagle 2 space probe on Mars, one of its instigators, Blur bassist Alex James, talks exclusively about his new-found passion for space 'Talking with scientists makes me feel giddy with excitement. Life on Mars, I mean, come on! How dead do you have to be not to find that interesting?' (1 page).

Healthy Sleep Habits

Science.gov (United States)

... Sleep Apnea Testing CPAP Healthy Sleep Habits Healthy Sleep Habits Your behaviors during the day, and especially ... team at an AASM accredited sleep center . Quick Sleep Tips Follow these tips to establish healthy sleep ...

A synthesis of Martian aqueous mineralogy after 1 Mars year of observations from the Mars Reconnaissance Orbiter

Science.gov (United States)

Murchie, S.L.; Mustard, J.F.; Ehlmann, B.L.; Milliken, R.E.; Bishop, J.L.; McKeown, N.K.; Noe Dobrea, E.Z.; Seelos, F.P.; Buczkowski, D.L.; Wiseman, S.M.; Arvidson, R. E.; Wray, J.J.; Swayze, G.; Clark, R.N.; Des Marais, D.J.; McEwen, A.S.; Bibring, J.-P.

2009-01-01

Martian aqueous mineral deposits have been examined and characterized using data acquired during Mars Reconnaissance Orbiter's (MRO) primary science phase, including Compact Reconnaissance Imaging Spectrometer for Mars hyperspectral images covering the 0.4-3.9 ??m wavelength range, coordinated with higher-spatial resolution HiRISE and Context Imager images. MRO's new high-resolution measurements, combined with earlier data from Thermal Emission Spectrometer; Thermal Emission Imaging System; and Observatoire pour la Min??ralogie, L'Eau, les Glaces et l'Activiti?? on Mars Express, indicate that aqueous minerals are both diverse and widespread on the Martian surface. The aqueous minerals occur in 9-10 classes of deposits characterized by distinct mineral assemblages, morphologies, and geologic settings. Phyllosilicates occur in several settings: in compositionally layered blankets hundreds of meters thick, superposed on eroded Noachian terrains; in lower layers of intracrater depositional fans; in layers with potential chlorides in sediments on intercrater plains; and as thousands of deep exposures in craters and escarpments. Carbonate-bearing rocks form a thin unit surrounding the Isidis basin. Hydrated silica occurs with hydrated sulfates in thin stratified deposits surrounding Valles Marineris. Hydrated sulfates also occur together with crystalline ferric minerals in thick, layered deposits in Terra Meridiani and in Valles Marineris and together with kaolinite in deposits that partially infill some highland craters. In this paper we describe each of the classes of deposits, review hypotheses for their origins, identify new questions posed by existing measurements, and consider their implications for ancient habitable environments. On the basis of current data, two to five classes of Noachian-aged deposits containing phyllosilicates and carbonates may have formed in aqueous environments with pH and water activities suitable for life. Copyright 2009 by the American

A reappraisal of the habitability of planets around M dwarf stars.

Science.gov (United States)

Tarter, Jill C; Backus, Peter R; Mancinelli, Rocco L; Aurnou, Jonathan M; Backman, Dana E; Basri, Gibor S; Boss, Alan P; Clarke, Andrew; Deming, Drake; Doyle, Laurance R; Feigelson, Eric D; Freund, Friedmann; Grinspoon, David H; Haberle, Robert M; Hauck, Steven A; Heath, Martin J; Henry, Todd J; Hollingsworth, Jeffery L; Joshi, Manoj M; Kilston, Steven; Liu, Michael C; Meikle, Eric; Reid, I Neill; Rothschild, Lynn J; Scalo, John; Segura, Antigona; Tang, Carol M; Tiedje, James M; Turnbull, Margaret C; Walkowicz, Lucianne M; Weber, Arthur L; Young, Richard E

2007-02-01

Stable, hydrogen-burning, M dwarf stars make up about 75% of all stars in the Galaxy. They are extremely long-lived, and because they are much smaller in mass than the Sun (between 0.5 and 0.08 M(Sun)), their temperature and stellar luminosity are low and peaked in the red. We have re-examined what is known at present about the potential for a terrestrial planet forming within, or migrating into, the classic liquid-surface-water habitable zone close to an M dwarf star. Observations of protoplanetary disks suggest that planet-building materials are common around M dwarfs, but N-body simulations differ in their estimations of the likelihood of potentially habitable, wet planets that reside within their habitable zones, which are only about one-fifth to 1/50th of the width of that for a G star. Particularly in light of the claimed detection of the planets with masses as small as 5.5 and 7.5 M(Earth) orbiting M stars, there seems no reason to exclude the possibility of terrestrial planets. Tidally locked synchronous rotation within the narrow habitable zone does not necessarily lead to atmospheric collapse, and active stellar flaring may not be as much of an evolutionarily disadvantageous factor as has previously been supposed. We conclude that M dwarf stars may indeed be viable hosts for planets on which the origin and evolution of life can occur. A number of planetary processes such as cessation of geothermal activity or thermal and nonthermal atmospheric loss processes may limit the duration of planetary habitability to periods far shorter than the extreme lifetime of the M dwarf star. Nevertheless, it makes sense to include M dwarf stars in programs that seek to find habitable worlds and evidence of life. This paper presents the summary conclusions of an interdisciplinary workshop (http://mstars.seti.org) sponsored by the NASA Astrobiology Institute and convened at the SETI Institute.

Drilling Automation Tests At A Lunar/Mars Analog Site

Science.gov (United States)

Glass, B.; Cannon, H.; Hanagud, S.; Lee, P.; Paulsen, G.

2006-01-01

Future in-situ lunar/martian resource utilization and characterization, as well as the scientific search for life on Mars, will require access to the subsurface and hence drilling. Drilling on Earth is hard - an art form more than an engineering discipline. The limited mass, energy and manpower in planetary drilling situations makes application of terrestrial drilling techniques problematic. The Drilling Automation for Mars Exploration (DAME) project is developing drilling automation and robotics for projected use in missions to the Moon and Mars in the 2011-15 period. This has been tested recently, drilling in permafrost at a lunar/martian analog site (Haughton Crater, Devon Island, Canada).

Voice Habits and Behaviors: Voice Care Among Flamenco Singers.

Science.gov (United States)

Garzón García, Marina; Muñoz López, Juana; Y Mendoza Lara, Elvira

2017-03-01

The purpose of this study is to analyze the vocal behavior of flamenco singers, as compared with classical music singers, to establish a differential vocal profile of voice habits and behaviors in flamenco music. Bibliographic review was conducted, and the Singer's Vocal Habits Questionnaire, an experimental tool designed by the authors to gather data regarding hygiene behavior, drinking and smoking habits, type of practice, voice care, and symptomatology perceived in both the singing and the speaking voice, was administered. We interviewed 94 singers, divided into two groups: the flamenco experimental group (FEG, n = 48) and the classical control group (CCG, n = 46). Frequency analysis, a Likert scale, and discriminant and exploratory factor analysis were used to obtain a differential profile for each group. The FEG scored higher than the CCG in speaking voice symptomatology. The FEG scored significantly higher than the CCG in use of "inadequate vocal technique" when singing. Regarding voice habits, the FEG scored higher in "lack of practice and warm-up" and "environmental habits." A total of 92.6% of the subjects classified themselves correctly in each group. The Singer's Vocal Habits Questionnaire has proven effective in differentiating flamenco and classical singers. Flamenco singers are exposed to numerous vocal risk factors that make them more prone to vocal fatigue, mucosa dehydration, phonotrauma, and muscle stiffness than classical singers. Further research is needed in voice training in flamenco music, as a means to strengthen the voice and enable it to meet the requirements of this musical genre. Copyright © 2017 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

CANDIDATE PLANETS IN THE HABITABLE ZONES OF KEPLER STARS

International Nuclear Information System (INIS)

Gaidos, Eric

2013-01-01

A key goal of the Kepler mission is the discovery of Earth-size transiting planets in ''habitable zones'' where stellar irradiance maintains a temperate climate on an Earth-like planet. Robust estimates of planet radius and irradiance require accurate stellar parameters, but most Kepler systems are faint, making spectroscopy difficult and prioritization of targets desirable. The parameters of 2035 host stars were estimated by Bayesian analysis and the probabilities p HZ that 2738 candidate or confirmed planets orbit in the habitable zone were calculated. Dartmouth Stellar Evolution Program models were compared to photometry from the Kepler Input Catalog, priors for stellar mass, age, metallicity and distance, and planet transit duration. The analysis yielded probability density functions for calculating confidence intervals of planet radius and stellar irradiance, as well as p HZ . Sixty-two planets have p HZ > 0.5 and a most probable stellar irradiance within habitable zone limits. Fourteen of these have radii less than twice the Earth; the objects most resembling Earth in terms of radius and irradiance are KOIs 2626.01 and 3010.01, which orbit late K/M-type dwarf stars. The fraction of Kepler dwarf stars with Earth-size planets in the habitable zone (η ⊕ ) is 0.46, with a 95% confidence interval of 0.31-0.64. Parallaxes from the Gaia mission will reduce uncertainties by more than a factor of five and permit definitive assignments of transiting planets to the habitable zones of Kepler stars.

Advantages of a Modular Mars Surface Habitat Approach

Science.gov (United States)

Rucker, Michelle A.; Hoffman, Stephan J.; Andrews, Alida; Watts, Kevin

2018-01-01

Early crewed Mars mission concepts developed by the National Aeronautics and Space Administration (NASA) assumed a single, large habitat would house six crew members for a 500-day Mars surface stay. At the end of the first mission, all surface equipment, including the habitat, -would be abandoned and the process would be repeated at a different Martian landing site. This work was documented in a series of NASA publications culminating with the Mars Design Reference Mission 5.0 (NASA-SP-2009-566). The Evolvable Mars Campaign (EMC) explored whether re-using surface equipment at a single landing site could be more affordable than the Apollo-style explore-abandon-repeat mission cadence. Initial EMC assumptions preserved the single, monolithic habitat, the only difference being a new requirement to reuse the surface habitat for multiple expedition crews. A trade study comparing a single large habitat versus smaller, modular habitats leaned towards the monolithic approach as more mass-efficient. More recent work has focused on the operational aspects of building up Mars surface infrastructure over multiple missions, and has identified compelling advantages of the modular approach that should be considered before making a final decision. This paper explores Mars surface mission operational concepts and integrated system analysis, and presents an argument for the modular habitat approach.

Construction of Power Receiving Rectenna Using Mars- In-Situ Materials; A Low Energy Materials Processing Approach

Science.gov (United States)

Curreri, Peter A.; Rose, M. Franklin (Technical Monitor)

2001-01-01

It is highly desirable to have a non-nuclear power rich option for the human exploration of Mars. Utilizing a Solar Electric Propulsion, SEP, / Power Beaming architecture for a non-nuclear power option for a human Mars base potentially avoids the weather and dust sensitivities of the surface photovoltaic option. Further from Mars areosynchronous orbit near year round power can be provided. Mission analysis, however, concludes that ultra high (245 GHz) frequencies or laser transmission technologies are required for Mars landed mass competitiveness with the surface photovoltaic option if the receiving rectifying antenna "rectenna" is transported from Earth. It is suggested in this paper that producing rectenna in situ on Mars surface might make a more conventional 5.8 GHz system competitive with surface PV. The premium of a competitive, robust, continuous base power might make the development of a 10 plus MWe class SEP for human Mars mission a more attractive non-nuclear option.

Processing OMEGA/Mars Express hyperspectral imagery from radiance-at-sensor to surface reflectance

NARCIS (Netherlands)

Bakker, W.H.; Ruitenbeek, F.J.A. van; Werff, H.M.A. van der; Zegers, T.E.; Oosthoek, J.H.P.; Marsh, S.H.; Meer, F.D. van der

2014-01-01

OMEGA/Mars Express hyperspectral imagery is an excellent source of data for exploring the surface composition of the planet Mars. Compared to terrestrial hyperspectral imagery, the data are challenging to work with; scene-specific transmission models are lacking, spectral features are shallow making

Coupling the severe accident code SCDAP with the system thermal hydraulic code MARS

Energy Technology Data Exchange (ETDEWEB)

Lee, Young Jin; Chung, Bub Dong [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

2004-07-01

MARS is a best-estimate system thermal hydraulics code with multi-dimensional modeling capability. One of the aims in MARS code development is to make it a multi-functional code system with the analysis capability to cover the entire accident spectrum. For this purpose, MARS code has been coupled with a number of other specialized codes such as CONTEMPT for containment analysis, and MASTER for 3-dimensional kinetics. And in this study, the SCDAP code has been coupled with MARS to endow the MARS code system with severe accident analysis capability. With the SCDAP, MARS code system now has acquired the capability to simulate such severe accident related phenomena as cladding oxidation, melting and slumping of fuel and reactor structures.

Coupling the severe accident code SCDAP with the system thermal hydraulic code MARS

International Nuclear Information System (INIS)

Lee, Young Jin; Chung, Bub Dong

2004-01-01

MARS is a best-estimate system thermal hydraulics code with multi-dimensional modeling capability. One of the aims in MARS code development is to make it a multi-functional code system with the analysis capability to cover the entire accident spectrum. For this purpose, MARS code has been coupled with a number of other specialized codes such as CONTEMPT for containment analysis, and MASTER for 3-dimensional kinetics. And in this study, the SCDAP code has been coupled with MARS to endow the MARS code system with severe accident analysis capability. With the SCDAP, MARS code system now has acquired the capability to simulate such severe accident related phenomena as cladding oxidation, melting and slumping of fuel and reactor structures

The automatic component of habit in health behavior: habit as cue-contingent automaticity.

Science.gov (United States)

Orbell, Sheina; Verplanken, Bas

2010-07-01

Habit might be usefully characterized as a form of automaticity that involves the association of a cue and a response. Three studies examined habitual automaticity in regard to different aspects of the cue-response relationship characteristic of unhealthy and healthy habits. In each study, habitual automaticity was assessed by the Self-Report Habit Index (SRHI). In Study 1 SRHI scores correlated with attentional bias to smoking cues in a Stroop task. Study 2 examined the ability of a habit cue to elicit an unwanted habit response. In a prospective field study, habitual automaticity in relation to smoking when drinking alcohol in a licensed public house (pub) predicted the likelihood of cigarette-related action slips 2 months later after smoking in pubs had become illegal. In Study 3 experimental group participants formed an implementation intention to floss in response to a specified situational cue. Habitual automaticity of dental flossing was rapidly enhanced compared to controls. The studies provided three different demonstrations of the importance of cues in the automatic operation of habits. Habitual automaticity assessed by the SRHI captured aspects of a habit that go beyond mere frequency or consistency of the behavior. PsycINFO Database Record (c) 2010 APA, all rights reserved.

Rearing a reading habit

OpenAIRE

Sridhar, M. S.

2009-01-01

Discusses the importance and ways of inculcating reading habit in children at the right age, describes the five reading phases in children along with interest and the material to satiate the need, explains how four deterministic factors affect the reading habit of children, enlists motivations that are behind the reading process with tips to improve reading habit of children.

Scientific Payload Of The Emirates Mars Mission: Emirates Mars Infrared Spectrometer (Emirs) Overview.

Science.gov (United States)

Altunaiji, E. S.; Edwards, C. S.; Christensen, P. R.; Smith, M. D.; Badri, K. M., Sr.

2017-12-01

The Emirates Mars Mission (EMM) will launch in 2020 to explore the dynamics in the atmosphere of Mars on a global scale. EMM has three scientific instruments to an improved understanding of circulation and weather in the Martian lower and middle atmosphere. Two of the EMM's instruments, which are the Emirates eXploration Imager (EXI) and Emirates Mars Infrared Spectrometer (EMIRS) will focus on the lower atmosphere observing dust, ice clouds, water vapor and ozone. On the other hand, the third instrument Emirates Mars Ultraviolet Spectrometer (EMUS) will focus on both the thermosphere of the planet and its exosphere. The EMIRS instrument, shown in Figure 1, is an interferometric thermal infrared spectrometer that is jointly developed by Arizona State University (ASU) and Mohammed Bin Rashid Space Centre (MBRSC). It builds on a long heritage of thermal infrared spectrometers designed, built, and managed, by ASU's Mars Space Flight Facility, including the Thermal Emission Spectrometer (TES), Miniature Thermal Emission Spectrometer (Mini-TES), and the OSIRIS-REx Thermal Emission Spectrometer (OTES). EMIRS operates in the 6-40+ µm range with 5 cm-1 spectral sampling, enabled by a Chemical Vapor-Deposited (CVD) diamond beamsplitter and state of the art electronics. This instrument utilizes a 3×3 detector array and a scan mirror to make high-precision infrared radiance measurements over most of a Martian hemisphere. The EMIRS instrument is optimized to capture the integrated, lower-middle atmosphere dynamics over a Martian hemisphere and will capture 60 global images per week ( 20 images per orbit) at a resolution of 100-300 km/pixel. After processing through an atmospheric retrieval algorithm, EMIRS will determine the vertical temperature profiles to 50km altitude and measure the column integrated global distribution and abundances of key atmospheric parameters (e.g. dust, water ice (clouds) and water vapor) over the Martian day, seasons and year.

A wide variety of putative extremophiles and large beta-diversity at the Mars Desert Research Station.

NARCIS (Netherlands)

Oliveira Lebre Direito, M.S.; Ehrenfreund, P.; Marees, A.; Staats, M.; Roling, W.F.M.

2011-01-01

Humankind's innate curiosity makes us wonder whether life is or was present on other planetary bodies such as Mars. The EuroGeoMars 2009 campaign was organized at the Mars Desert Research Station (MDRS) to perform multidisciplinary astrobiology research. MDRS in southeast Utah is situated in a cold

Fatty Acid Detection in Mars-Analogous Rock Samples with the TMAH Wet Chemistry Experiment on the Sample Analysis at Mars (SAM) Instrument

Science.gov (United States)

Williams, A. J.; Eigenbrode, J. L.; Wilhelm, M. B.; Johnson, S. S.; Craft, K.; O'Reilly, S.; Lewis, J. M. T.; Williams, R.; Summons, R. E.; Benison, K. C.; Mahaffy, P. R.

2017-12-01

The Curiosity rover is exploring sedimentary rock sequences in Gale Crater for evidence of habitability and searching for organic compounds using the Sample Analysis at Mars (SAM) instrument suite. SAM includes a gas chromatograph mass spectrometer (GC-MS) and pyrolysis ovens. SAM has the ability to perform wet chemistry experiments, one of which uses tetramethylammonium hydroxide (TMAH) thermochemolysis to liberate bound lipids, making them sufficiently volatile for detection by GC-MS. To determine the effectiveness of the SAM-like TMAH experiment on fatty acid methyl ester (FAME) biomarker identification, rock and sediment samples were collected from a variety of Mars analog environments including iron oxides from a modern mineral precipitate and older surface gossan at Iron Mountain, CA, as well as modern acid salt and neutral lake sediments with mixed iron oxides and clays from Western Australia; siliceous sinter from recently inactive and modern near-vent Icelandic hot springs deposits; modern carbonate ooids from The Bahamas, and organic-rich shale from Germany. Samples underwent pyrolysis with TMAH. Fatty acids were analyzed by pyro-GC-MS using a SAM-like heating ramp (35°C/min) as well as a 500°C flash on a Frontier pyrolyzer and Agilent GC-MS instrument. Results reveal that FAMEs were detectable with the TMAH experiment in nearly all samples. Low molecular weight (MW) C6:0-C10:0 FAMEs were present in all samples, medium MW C11:0-C18:2 FAMEs were present in select samples, and high MW (HMW) C20:0-C30:0 FAMEs were present in the shale sample. Many of these samples exhibited an even-over-odd carbon number preference, indicating biological production. These experiments demonstrate that TMAH thermochemolysis with SAM-like pyro-GC-MS is effective in fatty acid analysis from natural Mars-analog samples that vary in mineralogy, age, and microbial community input. HMW FAMEs are not detected in iron-dominated samples, and may not be detectable at low

Space Station Habitability Research

Science.gov (United States)

Clearwater, Yvonne A.

1988-01-01

The purpose and scope of the Habitability Research Group within the Space Human Factors Office at the NASA/Ames Research Center is described. Both near-term and long-term research objectives in the space human factors program pertaining to the U.S. manned Space Station are introduced. The concept of habitability and its relevancy to the U.S. space program is defined within a historical context. The relationship of habitability research to the optimization of environmental and operational determinants of productivity is discussed. Ongoing habitability research efforts pertaining to living and working on the Space Station are described.

Eating Habits and Body Weight Control Behaviors of High School Students

Directory of Open Access Journals (Sweden)

Aynur CETINKAYA

2007-04-01

Full Text Available The nutritional needs increase in puberty due to rapid growth and changes in body composition. Because of that healthy eating is vital for teen’s health. The aim of this study was to determine eating habits and weight control behaviors of high school students. A cross-sectional study was performed involving all (6 public and 3 private tenth-grade high schools in Manisa city. Two thousand one hundred forty six students completed a questionnaire which consists of 26 items and was designed by researchers. Among all students surveyed, 34.0% reported that they don’t have a habit to eat breakfast regularly, 38.3% reported that they don’t have a habit to eat lunch regularly, 6.5% reported that they don’t have a habit to eat dinner regularly, 36.7% reported that they were afraid getting fat, 6.5% reported that they were dieting, 39.4% reported that they don’t make sport regularly and 59.1% reported that they were snacking frequently. In this study it has seen that skipping meals is a common eating habit in high school students and many of them fail to eat three regular meals per day. On the other hand it has seen that students don’t have regular exercise habits. The results of this study have suggested that there is a need to encourage teens a healthy lifestyle that incorporates eating habits and regular exercise. [TAF Prev Med Bull. 2007; 6(2: 98-105

Eating Habits and Body Weight Control Behaviors of High School Students

Directory of Open Access Journals (Sweden)

Dilek OZMEN

2007-04-01

Full Text Available The nutritional needs increase in puberty due to rapid growth and changes in body composition. Because of that healthy eating is vital for teen’s health. The aim of this study was to determine eating habits and weight control behaviors of high school students. A cross-sectional study was performed involving all (6 public and 3 private tenth-grade high schools in Manisa city. Two thousand one hundred forty six students completed a questionnaire which consists of 26 items and was designed by researchers. Among all students surveyed, 34.0% reported that they don’t have a habit to eat breakfast regularly, 38.3% reported that they don’t have a habit to eat lunch regularly, 6.5% reported that they don’t have a habit to eat dinner regularly, 36.7% reported that they were afraid getting fat, 6.5% reported that they were dieting, 39.4% reported that they don’t make sport regularly and 59.1% reported that they were snacking frequently. In this study it has seen that skipping meals is a common eating habit in high school students and many of them fail to eat three regular meals per day. On the other hand it has seen that students don’t have regular exercise habits. The results of this study have suggested that there is a need to encourage teens a healthy lifestyle that incorporates eating habits and regular exercise. [TAF Prev Med Bull 2007; 6(2.000: 98-105

Russian contribution to the ExoMars project

Science.gov (United States)

Zelenyi, L.; Korablev, O.; Rodionov, D.; Khartov, V.; Martynov, M.; Lukyanchikov, A.

2014-04-01

The ExoMars ESA-led mission is dedicated to study of Mars and in particular its habitability. It consists of two launches, one planned in 2016 to deliver to Mars a telecommunication and science orbiter Trace Gas Orbiter (TGO) and a demonstrator of entry into the atmosphere and landing on the Mars surface, Entry, Descent and Landing Demonstrator Module (EDM). In 2018 a rover with drilling capability will be delivered to the surface of Mars. Since 2012 this mission, previously planned in cooperation with NASA is being developed in cooperation with Roscosmos. Both launches are planned with Proton-Breeze. In 2016 Russia contributes a significant part of the TGO science payload. In 2018 the landing will be provided by a joint effort capitalizing on the EDM technology. Russia contributes few science instruments for the rover, and leads the development of a long-living geophysical platform on the surface of Mars. Russian science instruments for TGO, the Atmospheric Chemistry Suite (ACS) and the Fine Resolution Epithermal Neutrons Detector (FREND) constituent a half of its scientific payload, European instrument being NOMAD for mapping and detection of trace species, and CASSIS camera for high-resolution mapping of target areas. The ACS package consists of three spectrometers covering spectral range from 0.7 to 17 μm with spectral resolving power reaching 50000. It is dedicated to studies of the composition of the Martian atmosphere and the Martian climate. FREND is a neutron detector with a collimation module, which significantly narrows the field of view of the instrument, allowing to create higher resolution maps of hydrogen-abundant regions on Mars. The spatial resolution of FREND will be ~40 km from the 400- km TGO orbit that is ~10 times better than HEND on Mars-Odyssey. Additionally, FREND includes a dosimeter module for monitoring radiation levels in orbit around Mars. In the 2018 mission, Russia takes the major responsibility of the descent module. The primary

The Astrobiology Habitable Environments Database (AHED)

Science.gov (United States)

Lafuente, B.; Stone, N.; Downs, R. T.; Blake, D. F.; Bristow, T.; Fonda, M.; Pires, A.

2015-12-01

The Astrobiology Habitable Environments Database (AHED) is a central, high quality, long-term searchable repository for archiving and collaborative sharing of astrobiologically relevant data, including, morphological, textural and contextural images, chemical, biochemical, isotopic, sequencing, and mineralogical information. The aim of AHED is to foster long-term innovative research by supporting integration and analysis of diverse datasets in order to: 1) help understand and interpret planetary geology; 2) identify and characterize habitable environments and pre-biotic/biotic processes; 3) interpret returned data from present and past missions; 4) provide a citable database of NASA-funded published and unpublished data (after an agreed-upon embargo period). AHED uses the online open-source software "The Open Data Repository's Data Publisher" (ODR - http://www.opendatarepository.org) [1], which provides a user-friendly interface that research teams or individual scientists can use to design, populate and manage their own database according to the characteristics of their data and the need to share data with collaborators or the broader scientific community. This platform can be also used as a laboratory notebook. The database will have the capability to import and export in a variety of standard formats. Advanced graphics will be implemented including 3D graphing, multi-axis graphs, error bars, and similar scientific data functions together with advanced online tools for data analysis (e. g. the statistical package, R). A permissions system will be put in place so that as data are being actively collected and interpreted, they will remain proprietary. A citation system will allow research data to be used and appropriately referenced by other researchers after the data are made public. This project is supported by the Science-Enabling Research Activity (SERA) and NASA NNX11AP82A, Mars Science Laboratory Investigations. [1] Nate et al. (2015) AGU, submitted.

Habit in Personality and Social Psychology.

Science.gov (United States)

Wood, Wendy

2017-11-01

Habits are largely absent from modern social and personality psychology. This is due to outdated perspectives that placed habits in conflict with goals. In modern theorizing, habits are represented in memory as implicit context-response associations, and they guide responding in conjunction with goals. Habits thus have important implications for our field. Emerging research shows that habits are an important mechanism by which people self-regulate and achieve long-term goals. Also, habits change through specific interventions, such as changes in context cues. I speculate that understanding of habits also holds promise for reducing intergroup discrimination and for understanding lay theories of the causes for action. In short, by recognizing habit, the field gains understanding of a central mechanism by which actions persist in daily life.

Telecommunications and navigation systems design for manned Mars exploration missions

Science.gov (United States)

Hall, Justin R.; Hastrup, Rolf C.

1989-06-01

This paper discusses typical manned Mars exploration needs for telecommunications, including preliminary navigation support functions. It is a brief progress report on an ongoing study program within the current NASA JPL Deep Space Network (DSN) activities. A typical Mars exploration case is defined, and support approaches comparing microwave and optical frequency performance for both local in situ and Mars-earth links are described. Optical telecommunication and navigation technology development opportunities in a Mars exploration program are also identified. A local Mars system telecommunication relay and navigation capability for service support of all Mars missions has been proposed as part of an overall solar system communications network. The effects of light-time delay and occultations on real-time mission decision-making are discussed; the availability of increased local mass data storage may be more important than increasing peak data rates to earth. The long-term frequency use plan will most likely include a mix of microwave, millimeter-wave and optical link capabilities to meet a variety of deep space mission needs.

MARS CODE MANUAL VOLUME III - Programmer's Manual

International Nuclear Information System (INIS)

Chung, Bub Dong; Hwang, Moon Kyu; Jeong, Jae Jun; Kim, Kyung Doo; Bae, Sung Won; Lee, Young Jin; Lee, Won Jae

2010-02-01

Korea Advanced Energy Research Institute (KAERI) conceived and started the development of MARS code with the main objective of producing a state-of-the-art realistic thermal hydraulic systems analysis code with multi-dimensional analysis capability. MARS achieves this objective by very tightly integrating the one dimensional RELAP5/MOD3 with the multi-dimensional COBRA-TF codes. The method of integration of the two codes is based on the dynamic link library techniques, and the system pressure equation matrices of both codes are implicitly integrated and solved simultaneously. In addition, the Equation-Of-State (EOS) for the light water was unified by replacing the EOS of COBRA-TF by that of the RELAP5. This programmer's manual provides a complete list of overall information of code structure and input/output function of MARS. In addition, brief descriptions for each subroutine and major variables used in MARS are also included in this report, so that this report would be very useful for the code maintenance. The overall structure of the manual is modeled on the structure of the RELAP5 and as such the layout of the manual is very similar to that of the RELAP. This similitude to RELAP5 input is intentional as this input scheme will allow minimum modification between the inputs of RELAP5 and MARS3.1. MARS3.1 development team would like to express its appreciation to the RELAP5 Development Team and the USNRC for making this manual possible

The Search for Hesperian Organic Matter on Mars: Pyrolysis Studies of Sediments Rich in Sulfur and Iron.

Science.gov (United States)

Lewis, James M T; Najorka, Jens; Watson, Jonathan S; Sephton, Mark A

2018-04-01

Jarosite on Mars is of significant geological and astrobiological interest, as it forms in acidic aqueous conditions that are potentially habitable for acidophilic organisms. Jarosite can provide environmental context and may host organic matter. The most common extraction technique used to search for organic compounds on the surface of Mars is pyrolysis. However, thermal decomposition of jarosite releases oxygen into pyrolysis ovens, which degrades organic signals. Jarosite has a close association with the iron oxyhydroxide goethite in many depositional/diagenetic environments. Hematite can form by dehydration of goethite or directly from jarosite under certain aqueous conditions. Goethite and hematite are significantly more amenable than jarosite for pyrolysis experiments employed to search for organic matter. Analysis of the mineralogy and organic chemistry of samples from a natural acidic stream revealed a diverse response for organic compounds during pyrolysis of goethite-rich layers but a poor response for jarosite-rich or mixed jarosite-goethite samples. Goethite units that are associated with jarosite, but do not contain jarosite themselves, should be targeted for organic detection pyrolysis experiments on Mars. These findings are extremely timely, as exploration targets for Mars Science Laboratory include Vera Rubin Ridge (formerly known as "Hematite Ridge"), which may have formed from goethite precursors. Key Words: Mars-Pyrolysis-Jarosite-Goethite-Hematite-Biosignatures. Astrobiology 18, 454-464.

BASALT A: Basaltic Terrains in Idaho and Hawaii as Planetary Analogs for Mars Geology and Astrobiology

Science.gov (United States)

Hughes, Scott S.; Haberle, Christopher W.; Nawotniak, Shannon E. Kobs; Sehlke, Alexander; Garry, W. Brent; Elphic, Richard C.; Payler, Sam J.; Stevens, Adam H.; Cockell, Charles S.; Brady, Allyson L.;

Recasting the Understanding of Habits for Behaviour-Oriented Policies in Transportation

Directory of Open Access Journals (Sweden)

Kevin Marechal

2018-03-01

Full Text Available The role of habits in influencing transportation behaviour is acknowledged in many studies. However, most of these analyses draw on a narrow perspective of habits. In this paper, we adopt a reversed perspective regarding the interplay between habits and rationality. The insightfulness of this perspective is illustrated with the findings of two empirical studies on urban transportation. This paper shows that the underlying structure (i.e., the “genotype” behind the phenotypic manifestation of a habit is essential to grasp for getting a better understanding of the role played by habits in explaining car use. The framework of habitual practices is then put forward in discussing the results. Its rationale is to provide a characterisation of the interconnected elements that make and shape the transportation practices, together with important aspects regarding how they are formed and sustained over time. Adequately picturing both constituent elements as well as dynamic aspects is crucial for explaining the strength of habitual practices and thus car dependence. In doing so, the framework of habitual practices could thus well be of help for policy-makers in reflecting on the design of efficient and innovative interventions for the transition towards more sustainable transportation behaviours.

MISSION PROFILE AND DESIGN CHALLENGES FOR MARS LANDING EXPLORATION

OpenAIRE

J. Dong; Z. Sun; W. Rao; Y. Jia; L. Meng; C. Wang; B. Chen

2017-01-01

An orbiter and a descent module will be delivered to Mars in the Chinese first Mars exploration mission. The descent module is composed of a landing platform and a rover. The module will be released into the atmosphere by the orbiter and make a controlled landing on Martian surface. After landing, the rover will egress from the platform to start its science mission. The rover payloads mainly include the subsurface radar, terrain camera, multispectral camera, magnetometer, anemometer to achiev...

Conditions on Early Mars Might Have Fostered Rapid and Early Development of Life

Science.gov (United States)

Gibson, Everett K.; McKay, David S.; Thomas-Keprta, Kathie L.; Clemett, Simon J.; Wentworth, Susan J.

2007-01-01

The exploration of Mars during the past decades has begun to unveil the history of the planet. The combinations of remote sensing, in situ geochemical compositional measurements and photographic observations from both above and on the surface have shown Mars to have a dynamic and active geologic evolution. Mars geologic evolution clearly had conditions that were suitable for supporting life. For a planet to be able to be habitable, it must have water, carbon sources, energy sources and a dynamic geologic past. Mars meets all of these requirements. The first 600 My of Martian history were ripe for life to develop because of the abundance of (i) Water-carved canyons and oceans or lakes with the early presence of near surface water shown by precipitated carbonates in ALH84001 well-dated at approx.3.9 Gy., (ii) Energy from the original accretional processes, a molten core which generated a strong magnetic field leaving a permanent record in the early crust, early active volcanism continuing throughout Martian history, and, and continuing impact processes, (iii) Carbon and water from possibly extensive volcanic outgassing (i.e. H2O, CO2, CH4, CO, O2, N2, H2S, SO2, etc.) and (iv) some crustal tectonics as revealed by faulting and possible plate movement reflected by the magnetic pattern in the crust. The question arises: "Why would life not evolve from these favorable conditions on early Mars in its first 600 My?" During this period, it seems likely that environmental near-surface conditions on Mars were more favorable to life than at any later time. Standing bodies of water, precipitation and flowing surface water, and possibly abundant hydrothermal energy would all favor the formation of early life. Even if life developed elsewhere (on Earth, Venus, or on other solar systems) and was transported to Mars, the surface conditions were likely very hospitable for that introduced life to multiply and evolve.

Dietary habits among persons hired on shift work.

Science.gov (United States)

Strzemecka, Joanna; Bojar, Iwona; Strzemecka, Ewa; Owoc, Alfred

2014-01-01

Shift-work determinates irregular nutrition habits. The quality as well as the quantity of meals consumed by shift-workers can significantly affects their health. The aim of this study was to evaluate the dietary habits of people performing shift work in the Bogdanka mine. The study was carried out in the Bogdanka mine in Leczna. The questionnaire, which was designed by the author of this dissertation, was conducted among 700 shift-workers, working underground. The results were subjected to statistical analysis based on STATISTICA v. 7.1 (StatSoft, Poland) software. Nearly half of respondents reported regular consumption of meals (40.0%) Interviewees admitted having warm meals during the day (81.4%). The most frequently consumed meal during the day was the hot one (50.9%), three meals and more were consumed the least frequently (8.1%). Almost half of respondents considered their eating habits as inappropriate (46.3%). Among those, nearly half (68.2%) stated that shift - work is the reason for their nutrition habits. More than half of respondents (66.0%) admitted that shift work hampers regular consumption of meals. Shift work makes nourishment and regular consumption difficult. It contributes to the limited amount of warm meals eaten during the day. In order to maintain preventive health care and the improvement of quality of life, shift workers should be provided with an easier access to meals (including warm one) at specified times of the day.

Habitability from Tidally Induced Tectonics

Science.gov (United States)

Valencia, Diana; Tan, Vivian Yun Yan; Zajac, Zachary

2018-04-01

The stability of Earth’s climate on geological timescales is enabled by the carbon–silicate cycle that acts as a negative feedback mechanism stabilizing surface temperatures via the intake and outgassing of atmospheric carbon. On Earth, this thermostat is enabled by plate tectonics that sequesters outgassed CO2 back into the mantle via weathering and subduction at convergent margins. Here we propose a separate tectonic mechanism—vertical recycling—that can serve as the vehicle for CO2 outgassing and sequestration over long timescales. The mechanism requires continuous tidal heating, which makes it particularly relevant to planets in the habitable zone of M stars. Dynamical models of this vertical recycling scenario and stability analysis show that temperate climates stable over timescales of billions of years are realized for a variety of initial conditions, even as the M star dims over time. The magnitude of equilibrium surface temperatures depends on the interplay of sea weathering and outgassing, which in turn depends on planetary carbon content, so that planets with lower carbon budgets are favored for temperate conditions. The habitability of planets such as found in the Trappist-1 system may be rooted in tidally driven tectonics.

Your Child's Habits

Science.gov (United States)

... older. For those who don't, simple behavior modification can help them break the habit. However, for those who start hair pulling as ... in your mirror. Do you bite your nails? Studies suggest that nail biting may ... kids engage in habits to attract attention or to manipulate their parents. ...

Mars bevares

DEFF Research Database (Denmark)

Hendricks, Vincent Fella; Hendricks, Elbert

2009-01-01

2009 er femåret for Mission Mars. I den anledning opridser de to kronikører, far og søn, hvorfor man bør lade planer om en bemandet tur til Mars forblive i skrivebordsskuffen......2009 er femåret for Mission Mars. I den anledning opridser de to kronikører, far og søn, hvorfor man bør lade planer om en bemandet tur til Mars forblive i skrivebordsskuffen...

A review and analysis of the use of 'habit' in understanding, predicting and influencing health-related behaviour.

Science.gov (United States)

Gardner, Benjamin

2015-01-01

The term 'habit' is widely used to predict and explain behaviour. This paper examines use of the term in the context of health-related behaviour, and explores how the concept might be made more useful. A narrative review is presented, drawing on a scoping review of 136 empirical studies and 8 literature reviews undertaken to document usage of the term 'habit', and methods to measure it. A coherent definition of 'habit', and proposals for improved methods for studying it, were derived from findings. Definitions of 'habit' have varied in ways that are often implicit and not coherently linked with an underlying theory. A definition is proposed whereby habit is a process by which a stimulus generates an impulse to act as a result of a learned stimulus-response association. Habit-generated impulses may compete or combine with impulses and inhibitions arising from other sources, including conscious decision-making, to influence responses, and need not generate behaviour. Most research on habit is based on correlational studies using self-report measures. Adopting a coherent definition of 'habit', and a wider range of paradigms, designs and measures to study it, may accelerate progress in habit theory and application.

Solar and wind exergy potentials for Mars

International Nuclear Information System (INIS)

Delgado-Bonal, Alfonso; Martín-Torres, F. Javier; Vázquez-Martín, Sandra; Zorzano, María-Paz

2016-01-01

The energy requirements of the planetary exploration spacecrafts constrain the lifetime of the missions, their mobility and capabilities, and the number of instruments onboard. They are limiting factors in planetary exploration. Several missions to the surface of Mars have proven the feasibility and success of solar panels as energy source. The analysis of the exergy efficiency of the solar radiation has been carried out successfully on Earth, however, to date, there is not an extensive research regarding the thermodynamic exergy efficiency of in-situ renewable energy sources on Mars. In this paper, we analyse the obtainable energy (exergy) from solar radiation under Martian conditions. For this analysis we have used the surface environmental variables on Mars measured in-situ by the Rover Environmental Monitoring Station onboard the Curiosity rover and from satellite by the Thermal Emission Spectrometer instrument onboard the Mars Global Surveyor satellite mission. We evaluate the exergy efficiency from solar radiation on a global spatial scale using orbital data for a Martian year; and in a one single location in Mars (the Gale crater) but with an appreciable temporal resolution (1 h). Also, we analyse the wind energy as an alternative source of energy for Mars exploration and compare the results with those obtained on Earth. We study the viability of solar and wind energy station for the future exploration of Mars, showing that a small square solar cell of 0.30 m length could maintain a meteorological station on Mars. We conclude that the low density of the atmosphere of Mars is responsible of the low thermal exergy efficiency of solar panels. It also makes the use of wind energy uneffective. Finally, we provide insights for the development of new solar cells on Mars. - Highlights: • We analyse the exergy of solar radiation under Martian environment • Real data from in-situ instruments is used to determine the maximum efficiency of radiation • Wind

A genealogical map of the concept of habit.

Science.gov (United States)

Barandiaran, Xabier E; Di Paolo, Ezequiel A

2014-01-01

The notion of information processing has dominated the study of the mind for over six decades. However, before the advent of cognitivism, one of the most prominent theoretical ideas was that of Habit. This is a concept with a rich and complex history, which is again starting to awaken interest, following recent embodied, enactive critiques of computationalist frameworks. We offer here a very brief history of the concept of habit in the form of a genealogical network-map. This serves to provide an overview of the richness of this notion and as a guide for further re-appraisal. We identify 77 thinkers and their influences, and group them into seven schools of thought. Two major trends can be distinguished. One is the associationist trend, starting with the work of Locke and Hume, developed by Hartley, Bain, and Mill to be later absorbed into behaviorism through pioneering animal psychologists (Morgan and Thorndike). This tradition conceived of habits atomistically and as automatisms (a conception later debunked by cognitivism). Another historical trend we have called organicism inherits the legacy of Aristotle and develops along German idealism, French spiritualism, pragmatism, and phenomenology. It feeds into the work of continental psychologists in the early 20th century, influencing important figures such as Merleau-Ponty, Piaget, and Gibson. But it has not yet been taken up by mainstream cognitive neuroscience and psychology. Habits, in this tradition, are seen as ecological, self-organizing structures that relate to a web of predispositions and plastic dependencies both in the agent and in the environment. In addition, they are not conceptualized in opposition to rational, volitional processes, but as transversing a continuum from reflective to embodied intentionality. These are properties that make habit a particularly attractive idea for embodied, enactive perspectives, which can now re-evaluate it in light of dynamical systems theory and complexity research.

A genealogical map of the concept of habit

Directory of Open Access Journals (Sweden)

Xabier E Barandiaran

2014-07-01

Full Text Available The notion of information processing has dominated the study of the mind for over six decades. However, before the advent of cognitivism, one of the most prominent theoretical ideas was that of Habit. This is a concept with a rich and complex history, which is again starting to awaken interest, following recent embodied, enactive critiques of computationalist frameworks. We offer here a very brief history of the concept of habit in the form of a genealogical network-map. This serves to provide an overview of the richness of this notion and as a guide for further re-appraisal. We identify 77 thinkers and their influences, and group them into seven schools of thought. Two major trends can be distinguished. One is the associationist trend, starting with the work of Locke and Hume, developed by Hartley, Bain and Mill to be later absorbed into behaviourism through pioneering animal psychologists (Morgan and Thorndike. This tradition conceived of habits atomistically and as automatisms (a conception later debunked by cognitivism. Another historical trend we have called organicism inherits the legacy of Aristotle and develops along German idealism, French spiritualism, pragmatism, and phenomenology. It feeds into the work of continental psychologists in the early 20th century, influencing important figures such as Merleau-Ponty, Piaget, and Gibson. But it has not yet been taken up by mainstream cognitive neuroscience and psychology. Habits, in this tradition, are seen as ecological, self-organizing structures that relate to a web of predispositions and plastic dependencies both in the agent and in the environment. In addition, they are not conceptualized in opposition to rational, volitional processes, but as transversing a continuum from reflective to embodied intentionality. These are properties that make habit a particularly attractive idea for embodied, enactive perspectives, which can now re-evaluate it in light of dynamical systems theory and

Ancient Martian aeolian processes and palaeomorphology reconstructed from the Stimson formation on the lower slope of Aeolis Mons, Gale crater, Mars

OpenAIRE

Banham, Steven G.; Gupta, Sanjeev; Rubin, David M.; Watkins, Jessica A.; Sumner, Dawn Y.; Edgett, Kenneth S.; Grotzinger, John P.; Lewis, Kevin W.; Edgar, Lauren A.; Stack-Morgan, Kathryn M.; Barnes, Robert; Bell, James F., III; Day, Mackenzie D.; Ewing, Ryan C.; Lapotre, Mathieu G. A.

2018-01-01

Reconstruction of the palaeoenvironmental context of Martian sedimentary rocks is central to studies of ancient Martian habitability and regional palaeoclimate history. This paper reports the analysis of a distinct aeolian deposit preserved in Gale crater, Mars, and evaluates its palaeomorphology, the processes responsible for its deposition, and its implications for Gale crater geological history and regional palaeoclimate. Whilst exploring the sedimentary succession cropping out on the nort...

Writing the History of Space Missions: Rosetta and Mars Express

Science.gov (United States)

Coradini, M.; Russo, A.

2011-10-01

Mars Express is the first planetary mission accomplished by the European Space Agency (ESA). Launched in early June 2003, the spacecraft entered Mars's orbit on Christmas day of that year, demonstrating the new European commitment to planetary exploration. Following a failed attempt in the mid-­-1980s, two valid proposals for a European mission to Mars were submitted to ESA's decision-­-making bodies in the early 1990s, in step with renewed international interest in Mars exploration. Both were rejected, however, in the competitive selection process for the agency's Science Programme. Eventually, the Mars Express proposal emerged during a severe budgetary crisis in the mid-­-1990s as an exemplar of a "flexible mission" that could reduce project costs and development time. Its successful maneuvering through financial difficulties and conflicting scientific interests was due to the new management approach as well as to the public appeal of Mars exploration. In addition to providing a case study in the functioning of the ESA's Science Programme, the story of Mars Express discussed in this paper provides a case study in the functioning of the European Space Agency's Science Programme and suggests some general considerations on the peculiar position of space research in the general field of the history of science and technology.

Mars Technologies Spawn Durable Wind Turbines

Science.gov (United States)

Bubenheim, David L.

2013-01-01

Sometimes referred to as regenerative life support systems, the concept includes an enclosed self-sufficient habitat that can independently support life for years on end. Such a system aims not only to produce its own food and water but to purify air and convert waste into useful byproducts. In the early 1990s, NASA was planning for an extended stay on Mars, and Bubenheim and his Ames colleagues were concentrating efforts on creating a complete ecological system to sustain human crewmembers during their time on the Red Planet. The main barrier to developing such a system, he says, is energy. Mars has no power plants, and a regenerative system requires equipment that runs on electricity to do everything from regulating humidity in the atmosphere to monitoring the quality of recycled water. The Ames group started looking at how to best make power on a planet that is millions of miles away from Earth and turned to a hybrid concept combining wind and solar power technologies. The reason was that Mars experiences frequent dust storms that can block nearly all sunlight. When theres a dust storm and the wind is blowing, the wind system could be the dominant power source. When the wind is not blowing and the sun is out, photovoltaics could be the dominant source, says Bubenheim.To develop and test the wind power technology, Ames turned to a remote, harsh environment here on Earth: the South Pole. The South Pole was a really good analog for Mars, says Bubenheim. The technology features for going to Mars were the same technology features needed to make something work at the South Pole.Around the same time that NASA started investigating energy technologies for the Red Planet, the National Science Foundation (NSF) was working on a redesign of their station at the South Pole. To power its operations, NSF used fuel that it flew to the remote location, but the Foundation recognized the benefits of also using onsite renewable energy technologies. In the winter they have small

Large wind ripples on Mars: A record of atmospheric evolution

Science.gov (United States)

Lapotre, M G; Ewing, R C; Lamb, M P; Fischer, W W; Grotzinger, J P; Rubin, D M; Lewis, K W; Ballard, M; Day, Mitch D.; Gupta, S.; Banham, S G; Bridges, N T; Des Marais, D J; Fraeman, A A; Grant, J A; Herkenhoff, Kenneth E.; Ming, D W; Mischna, M A; Rice, M S; Sumner, D A; Vasavada, A R; Yingst, R A

2016-01-01

Wind blowing over sand on Earth produces decimeter-wavelength ripples and hundred-meter– to kilometer-wavelength dunes: bedforms of two distinct size modes. Observations from the Mars Science Laboratory Curiosity rover and the Mars Reconnaissance Orbiter reveal that Mars hosts a third stable wind-driven bedform, with meter-scale wavelengths. These bedforms are spatially uniform in size and typically have asymmetric profiles with angle-of-repose lee slopes and sinuous crest lines, making them unlike terrestrial wind ripples. Rather, these structures resemble fluid-drag ripples, which on Earth include water-worked current ripples, but on Mars instead form by wind because of the higher kinematic viscosity of the low-density atmosphere. A reevaluation of the wind-deposited strata in the Burns formation (about 3.7 billion years old or younger) identifies potential wind-drag ripple stratification formed under a thin atmosphere.

Large wind ripples on Mars: A record of atmospheric evolution

Science.gov (United States)

Lapotre, M. G. A.; Ewing, R. C.; Lamb, M. P.; Fischer, W. W.; Grotzinger, J. P.; Rubin, D. M.; Lewis, K. W.; Ballard, M. J.; Day, M.; Gupta, S.; Banham, S. G.; Bridges, N. T.; Des Marais, D. J.; Fraeman, A. A.; Grant, J. A.; Herkenhoff, K. E.; Ming, D. W.; Mischna, M. A.; Rice, M. S.; Sumner, D. A.; Vasavada, A. R.; Yingst, R. A.

2016-07-01

Wind blowing over sand on Earth produces decimeter-wavelength ripples and hundred-meter- to kilometer-wavelength dunes: bedforms of two distinct size modes. Observations from the Mars Science Laboratory Curiosity rover and the Mars Reconnaissance Orbiter reveal that Mars hosts a third stable wind-driven bedform, with meter-scale wavelengths. These bedforms are spatially uniform in size and typically have asymmetric profiles with angle-of-repose lee slopes and sinuous crest lines, making them unlike terrestrial wind ripples. Rather, these structures resemble fluid-drag ripples, which on Earth include water-worked current ripples, but on Mars instead form by wind because of the higher kinematic viscosity of the low-density atmosphere. A reevaluation of the wind-deposited strata in the Burns formation (about 3.7 billion years old or younger) identifies potential wind-drag ripple stratification formed under a thin atmosphere.

Mars Surface System Common Capabilities and Challenges for Human Missions

Science.gov (United States)

Hoffman, Stephen J.; Toups, Larry

2016-01-01

NASA has begun a process to identify and evaluate candidate locations where humans could land, live and work on the martian surface. These locations are referred to as Exploration Zones (EZs). Given current mission concepts, an EZ is a collection of Regions of Interest (ROIs) that are located within approximately 100 kilometers of a centralized landing site. ROIs are areas that are relevant for scientific investigation and/or development/maturation of capabilities and resources necessary for a sustainable human presence. The EZ also contains a landing site and a habitation site that will be used by multiple human crews during missions to explore and utilize the ROIs within the EZ. In parallel with this process, NASA continues to make progress on the Evolvable Mars Campaign examining alternatives that can pioneer an extended human presence on Mars that is Earth independent. This involves ongoing assessments of surface systems and operations to enable a permanent, sustainable human presence. Because of the difficulty in getting equipment and supplies to the surface of Mars, part of these assessments involve identifying those systems and processes that can perform in multiple, sometimes completely unrelated, situations. These assessments have been performed in a very generic surface mission carried out at a very generic surface location. As specific candidate EZs are identified it becomes important to evaluate the current suite of surface systems and operations as they are likely to perform for the specific locations and for the types of operations - both scientific and development - that are proposed for these EZs. It is also important to evaluate the proposed EZs for their suitability to be explored or developed given the range of capabilities and constraints for the types of surface systems and operations being considered within the EMC. This means looking at setting up and operating a field station at a central location within the EZ as well as traversing to and

Unmanned systems to support the human exploration of Mars

Science.gov (United States)

Gage, Douglas W.

2010-04-01

Robots and other unmanned systems will play many critical roles in support of a human presence on Mars, including surveying candidate landing sites, locating ice and mineral resources, establishing power and other infrastructure, performing construction tasks, and transporting equipment and supplies. Many of these systems will require much more strength and power than exploration rovers. The presence of humans on Mars will permit proactive maintenance and repair, and allow teleoperation and operator intervention, supporting multiple dynamic levels of autonomy, so the critical challenges to the use of unmanned systems will occur before humans arrive on Mars. Nevertheless, installed communications and navigation infrastructure should be able to support structured and/or repetitive operations (such as excavation, drilling, or construction) within a "familiar" area with an acceptable level of remote operator intervention. This paper discusses some of the factors involved in developing and deploying unmanned systems to make humans' time on Mars safer and more productive, efficient, and enjoyable.

Anglophone Cameroon literature 1959–90: A brief overview

African Journals Online (AJOL)

2016-03-28

Mar 28, 2016 ... not the people's worry; nevertheless, they found that fact alone unbearable. The ... will make it fit for human habitation, what do they do? ... of Western influence. Again, in ... were attracted and made friends with them […] ...

Automatic Contextual Text Correction Using The Linguistic Habits Graph Lhg

Directory of Open Access Journals (Sweden)

Marcin Gadamer

2009-01-01

Full Text Available Automatic text correction is an essential problem of today text processors and editors. Thispaper introduces a novel algorithm for automation of contextual text correction using a LinguisticHabit Graph (LHG also introduced in this paper. A specialist internet crawler hasbeen constructed for searching through web sites in order to build a Linguistic Habit Graphafter text corpuses gathered in polish web sites. The achieved correction results on a basis ofthis algorithm using this LHG were compared with commercial programs which also enableto make text correction: Microsoft Word 2007, Open Office Writer 3.0 and search engineGoogle. The achieved results of text correction were much better than correction made bythese commercial tools.

Seemingly irrational driving behavior model: The effect of habit strength and anticipated affective reactions.

Science.gov (United States)

Chung, Yi-Shih

2015-09-01

An increasing amount of evidence suggests that aberrant driving behaviors are not entirely rational. On the basis of the dual-process theory, this study postulates that drivers may learn to perform irrational aberrant driving behaviors, and these behaviors could be derived either from a deliberate or an intuitive decision-making approach. Accordingly, a seemingly irrational driving behavior model is proposed; in this model, the theory of planned behavior (TPB) was adopted to represent the deliberate decision-making mechanism, and habit strength was incorporated to reflect the intuitive decision process. A multiple trivariate mediation structure was designed to reflect the process through which driving behaviors are learned. Anticipated affective reactions (AARs) were further included to examine the effect of affect on aberrant driving behaviors. Considering the example of speeding behaviors, this study developed scales and conducted a two-wave survey of students in two departments at a university in Northern Taiwan. The analysis results show that habit strength consists of multiple aspects, and frequency of past behavior cannot be a complete repository for accumulating habit strength. Habit strength appeared to be a crucial mediator between intention antecedents (e.g., attitude) and the intention itself. Including habit strength in the TPB model enhanced the explained variance of speeding intention by 26.7%. In addition, AARs were different from attitudes; particularly, young drivers tended to perform speeding behaviors to reduce negative feelings such as regret. The proposed model provides an effective alternative approach for investigating aberrant driving behaviors; corresponding countermeasures are discussed. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Supergalactic Habitable Zone

Science.gov (United States)

Mason, Paul

2018-01-01

Habitability in the local universe is examined. Constrained by metal abundance and exposure to sterilizing events, life as we know it requires significantly long periods of stable environmental conditions. Planets within galaxies undergoing major mergers, active AGN, starburst episodes, and merging black holes pose serious threats to long-term habitability. Importantly, the development of several layers of protection from high-energy particles such as a thick atmosphere, a strong planetary magnetic field, an astrosphere, and a galactic magnetic field is of great benefit. Factors such as star type and activity, planet type and composition, the location of a planet within its host galaxy, and even the location within a supercluster of galaxies can affect the potential habitability of planets. We discuss the concept of the Supergalactic Habitable Zone introduced by Mason and Biermann in terms of habitability in the local universe and find that galaxies near the center of the Virgo cluster, for example, have a much lower probability for the development of life as we know it as compared to locations in the Milky Way.

Ombuds' Corner: MARS interviews, an opportunity for new understandings (Part 1)

CERN Multimedia

Sudeshna Datta-Cockerill

2014-01-01

With the annual MARS exercise quickly approaching, now is an ideal time to consider how to carry out a successful interview. Whether you are a supervisor or a supervisee, preparation, and an open frame of mind, can turn the experience into much more than a formality.   "The MARS interviews are just a formality." "My supervisor doesn't seem to understand the effort that goes into my work." These are familiar complaints heard at CERN during MARS season. But with an open attitude and solid preparation, the annual interview can be an excellent opportunity to foster new understandings. If you are a supervisor, it is important to remember that people need to feel valued. Not only is the annual interview a time for discussing, understanding and acknowledging the work carried out by your supervisees, it's also an opportunity to make them feel valued for who they are and what they bring to the Organization. But what makes people feel valued? In pa...

Origin and stability of exomoon atmospheres: implications for habitability.

Science.gov (United States)

Lammer, Helmut; Schiefer, Sonja-Charlotte; Juvan, Ines; Odert, Petra; Erkaev, Nikolai V; Weber, Christof; Kislyakova, Kristina G; Güdel, Manuel; Kirchengast, Gottfried; Hanslmeier, Arnold

2014-09-01

We study the origin and escape of catastrophically outgassed volatiles (H2O, CO2) from exomoons with Earth-like densities and masses of 0.1, 0.5 and 1 M⊕ orbiting an extra-solar gas giant inside the habitable zone of a young active solar-like star. We apply a radiation absorption and hydrodynamic upper atmosphere model to the three studied exomoon cases. We model the escape of hydrogen and dragged dissociation products O and C during the activity saturation phase of the young host star. Because the soft X-ray and EUV radiation of the young host star may be up to ~100 times higher compared to today's solar value during the first 100 Myr after the system's origin, an exomoon with a mass 0.5 M⊕, however, may evolve to habitats that are a mixture of Mars-like and Earth-analogue habitats, so that life may originate and evolve at the exomoon's surface.

Addiction history associates with the propensity to form habits

Science.gov (United States)

McKim, Theresa H.; Bauer, Daniel J.; Boettiger, Charlotte A.

2016-01-01

Learned habitual responses to environmental stimuli allow efficient interaction with the environment, freeing cognitive resources for more demanding tasks. However, when the outcome of such actions is no longer a desired goal, established stimulus-response (S-R) associations, or habits, must be overcome. Among people with substance use disorders (SUDs), difficulty in overcoming habitual responses to stimuli associated with their addiction in favor of new, goal-directed behaviors, contributes to relapse. Animal models of habit learning demonstrate that chronic self-administration of drugs of abuse promotes habitual responding beyond the domain of compulsive drug seeking. However, whether a similar propensity toward domain-general habitual responding occurs in humans with SUDs has remained unclear. To address this question, we used a visuomotor S-R learning and re-learning task, the Hidden Association Between Images Task (HABIT), which employs abstract visual stimuli and manual responses. This task allows us to measure new S-R association learning, well-learned S-R association execution, and includes a response contingency change manipulation to quantify the degree to which responding is habit-based, rather than goal-directed. We find that people with SUDs learn new S-R associations as well as healthy control subjects do. Moreover, people with an SUD history slightly outperform controls in S-R execution. In contrast, people with SUDs are specifically impaired in overcoming well-learned S-R associations; those with SUDs make a significantly greater proportion of perseverative errors during well-learned S-R replacement, indicating the more habitual nature of their responses. Thus, with equivalent training and practice, people with SUDs appear to show enhanced domain-general habit formation. PMID:26967944

Preliminary Geological Map of the Peace Vallis Fan Integrated with In Situ Mosaics From the Curiosity Rover, Gale Crater, Mars

Science.gov (United States)

Sumner, D. Y.; Palucis, M.; Dietrich, B.; Calef, F.; Stack, K. M.; Ehlmann, B.; Bridges, J.; Dromart, J.; Eigenbrode, J.; Farmer, J.;

MARS CODE MANAUAL VOLUME IV - Developmental Assessment Report

International Nuclear Information System (INIS)

Chung, Bub Dong; Jeong, Jae Jun; Hwang, Moon Kyu; Lee, Won Jae; Lee, Young Jin; Lee, Seung Wook; Kim, Kyung Doo; Bae, Sung Won

2010-02-01

Korea Advanced Energy Research Institute (KAERI) conceived and started the development of MARS code with the main objective of producing a state-of-the-art realistic thermal hydraulic systems analysis code with multi-dimensional analysis capability. MARS achieves this objective by very tightly integrating the one dimensional RELAP5/MOD3 with the multi-dimensional COBRA-TF codes. The method of integration of the two codes is based on the dynamic link library techniques, and the system pressure equation matrices of both codes are implicitly integrated and solved simultaneously. In addition, the Equation-Of-State (EOS) for the light water was unified by replacing the EOS of COBRA-TF by that of the RELAP5. This assessment manual provides a complete list of code assessment results of the MARS code for various conceptual problem, separate effect test and integral effect test. From these validation procedures, the soundness and accuracy of the MARS code has been confirmed. The overall structure of the input is modeled on the structure of the RELAP5 and as such the layout of the manual is very similar to that of the RELAP. This similitude to RELAP5 input is intentional as this input scheme will allow minimum modification between the inputs of RELAP5 and MARS3.1. MARS3.1 development team would like to express its appreciation to the RELAP5 Development Team and the USNRC for making this manual possible

Knowledge of the inhabitants of Lubelskie region on proper eating habits

Directory of Open Access Journals (Sweden)

Dorota Weber

2017-08-01

  Due to the fact that care about health, where proper eating habits are one of its constituents, exerts a strong impact on both social and economic life of a country, it is not just an individual case of each person, but a public matter.  The state of health status is obviously subject to a number of factors. However, the habits and customs with regard to daily habits are of particular importance due to the significance of food for the physical existence of each human body. These habits are formed in childhood and youth, however they undergo modifications throughout the whole life. Quite frequently the possessed knowledge is not a sufficient motivation to make great changes in the manner of eating, thus it does not change the eating habits. The aim of the paper is to determine the level of knowledge of clinic patients, selected at random, on proper eating habits. Materials and methods The research was conducted during the period of January-February 2016 year in a Lublin clinic. The investigation comprised 148 respondents. The method used in the research was a diagnostic survey, and the selected technique was a questionnaire conducted among the respondents, using a birth certificate, an interview and an anthropometric study. The study included 148 persons, who were further divided into two groups: students and workers. The respondents were the inhabitants of Lublin and nearby villages. The survey findings underwent a static programme analysis in Statistica 9.1 software (StatSoft, Poland. Conclusions The identification of nutritional knowledge and dietary behaviours of consumers as well as determination of the level and diversity of their nutritional awareness should become the basis for the preparation of guidelines on the content of broadcasts in order to promote healthy eating habits among consumers of different groups.

Architectural Design for a Mars Communications and Navigation Orbital Infrastructure

Science.gov (United States)

Ceasrone R. J.; Hastrup, R. C.; Bell, D. J.; Roncoli, R. B.; Nelson, K.

1999-01-01

The planet Mars has become the focus of an intensive series of missions that span decades of time, a wide array of international agencies and an evolution from robotics to humans. The number of missions to Mars at any one time, and over a period of time, is unprecedented in the annals of space exploration. To meet the operational needs of this exploratory fleet will require the implementation of new architectural concepts for communications and navigation. To this end, NASA's Jet Propulsion Laboratory has begun to define and develop a Mars communications and navigation orbital infrastructure. This architecture will make extensive use of assets at Mars, as well as use of traditional Earth-based assets, such as the Deep Space Network, DSN. Indeed, the total system can be thought of as an extension of DSN nodes and services to the Mars in-situ region. The concept has been likened to the beginnings of an interplanetary Internet that will bring the exploration of Mars right into our living rooms. The paper will begin with a high-level overview of the concept for the Mars communications and navigation infrastructure. Next, the mission requirements will be presented. These will include the relatively near-term needs of robotic landers, rovers, ascent vehicles, balloons, airplanes, and possibly orbiting, arriving and departing spacecraft. Requirements envisioned for the human exploration of Mars will also be described. The important Mars orbit design trades on telecommunications and navigation capabilities will be summarized, and the baseline infrastructure will be described. A roadmap of NASA's plan to evolve this infrastructure over time will be shown. Finally, launch considerations and delivery to Mars will be briefly treated.

Dietary habits among persons hired on shift work

Directory of Open Access Journals (Sweden)

Joanna Strzemecka

2014-03-01

Full Text Available Introduction. Shift-work determinates irregular nutrition habits. The quality as well as the quantity of meals consumed by shift-workers can significantly affects their health. Objective. The aim of this study was to evaluate the dietary habits of people performing shift work in the Bogdanka mine. Material and Methods. The study was carried out in the Bogdanka mine in Leczna. The questionnaire, which was designed by the author of this dissertation, was conducted among 700 shift-workers, working underground. The results were subjected to statistical analysis based on STATISTICA v. 7.1 (StatSoft, Poland software. Results. Nearly half of respondents reported regular consumption of meals (40.0% Interviewees admitted having warm meals during the day (81.4%. The most frequently consumed meal during the day was the hot one (50.9%, three meals and more were consumed the least frequently (8.1%. Almost half of respondents considered their eating habits as inappropriate (46.3%. Among those, nearly half (68.2% stated that shift – work is the reason for their nutrition habits. More than half of respondents (66.0% admitted that shift work hampers regular consumption of meals. Conclusions. Shift work makes nourishment and regular consumption difficult. It contributes to the limited amount of warm meals eaten during the day. In order to maintain preventive health care and the improvement of quality of life, shift workers should be provided with an easier access to meals (including warm one at specified times of the day.

Habits in perioperative nursing culture.

Science.gov (United States)

Lindwall, Lillemor; von Post, Iréne

2008-09-01

This study focuses on investigating habits in perioperative nursing culture, which are often simply accepted and not normally considered or discussed. A hermeneutical approach was chosen as the means of understanding perioperative nurses' experiences of and reflections on operating theatre culture. Focus group discussions were used to collect data, which was analysed using hermeneutical text analysis. The results revealed three main categories of habits present in perioperative nursing culture: habits that promote ethical values (by temporary friendship with patients, showing respect for each other, and spending time on reflection on ethics and caring); habits that hinder progress (by seeing the patient as a surgical case, not acknowledging colleagues, and not talking about ethics); and habits that set the cultural tone (the hidden power structure and achieving more in less time).

Science Applications of a Multispectral Microscopic Imager for the Astrobiological Exploration of Mars

Science.gov (United States)

Farmer, Jack D.; Sellar, R. Glenn; Swayze, Gregg A.; Blaney, Diana L.

2014-01-01

Abstract Future astrobiological missions to Mars are likely to emphasize the use of rovers with in situ petrologic capabilities for selecting the best samples at a site for in situ analysis with onboard lab instruments or for caching for potential return to Earth. Such observations are central to an understanding of the potential for past habitable conditions at a site and for identifying samples most likely to harbor fossil biosignatures. The Multispectral Microscopic Imager (MMI) provides multispectral reflectance images of geological samples at the microscale, where each image pixel is composed of a visible/shortwave infrared spectrum ranging from 0.46 to 1.73 μm. This spectral range enables the discrimination of a wide variety of rock-forming minerals, especially Fe-bearing phases, and the detection of hydrated minerals. The MMI advances beyond the capabilities of current microimagers on Mars by extending the spectral range into the infrared and increasing the number of spectral bands. The design employs multispectral light-emitting diodes and an uncooled indium gallium arsenide focal plane array to achieve a very low mass and high reliability. To better understand and demonstrate the capabilities of the MMI for future surface missions to Mars, we analyzed samples from Mars-relevant analog environments with the MMI. Results indicate that the MMI images faithfully resolve the fine-scale microtextural features of samples and provide important information to help constrain mineral composition. The use of spectral endmember mapping reveals the distribution of Fe-bearing minerals (including silicates and oxides) with high fidelity, along with the presence of hydrated minerals. MMI-based petrogenetic interpretations compare favorably with laboratory-based analyses, revealing the value of the MMI for future in situ rover-mediated astrobiological exploration of Mars. Key Words: Mars—Microscopic imager—Multispectral imaging�

Science applications of a multispectral microscopic imager for the astrobiological exploration of Mars

Science.gov (United States)

Nunez, Jorge; Farmer, Jack; Sellar, R. Glenn; Swayze, Gregg A.; Blaney, Diana L.

2014-01-01

Future astrobiological missions to Mars are likely to emphasize the use of rovers with in situ petrologic capabilities for selecting the best samples at a site for in situ analysis with onboard lab instruments or for caching for potential return to Earth. Such observations are central to an understanding of the potential for past habitable conditions at a site and for identifying samples most likely to harbor fossil biosignatures. The Multispectral Microscopic Imager (MMI) provides multispectral reflectance images of geological samples at the microscale, where each image pixel is composed of a visible/shortwave infrared spectrum ranging from 0.46 to 1.73 μm. This spectral range enables the discrimination of a wide variety of rock-forming minerals, especially Fe-bearing phases, and the detection of hydrated minerals. The MMI advances beyond the capabilities of current microimagers on Mars by extending the spectral range into the infrared and increasing the number of spectral bands. The design employs multispectral light-emitting diodes and an uncooled indium gallium arsenide focal plane array to achieve a very low mass and high reliability. To better understand and demonstrate the capabilities of the MMI for future surface missions to Mars, we analyzed samples from Mars-relevant analog environments with the MMI. Results indicate that the MMI images faithfully resolve the fine-scale microtextural features of samples and provide important information to help constrain mineral composition. The use of spectral endmember mapping reveals the distribution of Fe-bearing minerals (including silicates and oxides) with high fidelity, along with the presence of hydrated minerals. MMI-based petrogenetic interpretations compare favorably with laboratory-based analyses, revealing the value of the MMI for future in situ rover-mediated astrobiological exploration of Mars.

A new analysis of Mars "Special Regions": findings of the second MEPAG Special Regions Science Analysis Group (SR-SAG2).

Science.gov (United States)

Rummel, John D; Beaty, David W; Jones, Melissa A; Bakermans, Corien; Barlow, Nadine G; Boston, Penelope J; Chevrier, Vincent F; Clark, Benton C; de Vera, Jean-Pierre P; Gough, Raina V; Hallsworth, John E; Head, James W; Hipkin, Victoria J; Kieft, Thomas L; McEwen, Alfred S; Mellon, Michael T; Mikucki, Jill A; Nicholson, Wayne L; Omelon, Christopher R; Peterson, Ronald; Roden, Eric E; Sherwood Lollar, Barbara; Tanaka, Kenneth L; Viola, Donna; Wray, James J

2014-11-01

A committee of the Mars Exploration Program Analysis Group (MEPAG) has reviewed and updated the description of Special Regions on Mars as places where terrestrial organisms might replicate (per the COSPAR Planetary Protection Policy). This review and update was conducted by an international team (SR-SAG2) drawn from both the biological science and Mars exploration communities, focused on understanding when and where Special Regions could occur. The study applied recently available data about martian environments and about terrestrial organisms, building on a previous analysis of Mars Special Regions (2006) undertaken by a similar team. Since then, a new body of highly relevant information has been generated from the Mars Reconnaissance Orbiter (launched in 2005) and Phoenix (2007) and data from Mars Express and the twin Mars Exploration Rovers (all 2003). Results have also been gleaned from the Mars Science Laboratory (launched in 2011). In addition to Mars data, there is a considerable body of new data regarding the known environmental limits to life on Earth-including the potential for terrestrial microbial life to survive and replicate under martian environmental conditions. The SR-SAG2 analysis has included an examination of new Mars models relevant to natural environmental variation in water activity and temperature; a review and reconsideration of the current parameters used to define Special Regions; and updated maps and descriptions of the martian environments recommended for treatment as "Uncertain" or "Special" as natural features or those potentially formed by the influence of future landed spacecraft. Significant changes in our knowledge of the capabilities of terrestrial organisms and the existence of possibly habitable martian environments have led to a new appreciation of where Mars Special Regions may be identified and protected. The SR-SAG also considered the impact of Special Regions on potential future human missions to Mars, both as locations of

Cars on Mars

Science.gov (United States)

Landis, Geoffrey A.

2002-01-01

Mars is one of the most fascinating planets in the solar system, featuring an atmosphere, water, and enormous volcanoes and canyons. The Mars Pathfinder, Global Surveyor, and Odyssey missions mark the first wave of the Planet Earth's coming invasion of the red planet, changing our views of the past and future of the planet and the possibilities of life. Scientist and science-fiction writer Geoffrey A. Landis will present experiences on the Pathfinder mission, the challenges of using solar power on the surface of Mars, and present future missions to Mars such as the upcoming Mars Twin Rovers, which will launch two highly-capable vehicles in 2003 to explore the surface of Mars.

Two Moons and the Pleiades from Mars

Science.gov (United States)

2005-01-01

[figure removed for brevity, see original site] Inverted image of two moons and the Pleiades from Mars Taking advantage of extra solar energy collected during the day, NASA's Mars Exploration Rover Spirit recently settled in for an evening of stargazing, photographing the two moons of Mars as they crossed the night sky. In this view, the Pleiades, a star cluster also known as the 'Seven Sisters,' is visible in the lower left corner. The bright star Aldebaran and some of the stars in the constellation Taurus are visible on the right. Spirit acquired this image the evening of martian day, or sol, 590 (Aug. 30, 2005). The image on the right provides an enhanced-contrast view with annotation. Within the enhanced halo of light is an insert of an unsaturated view of Phobos taken a few images later in the same sequence. On Mars, Phobos would be easily visible to the naked eye at night, but would be only about one-third as large as the full Moon appears from Earth. Astronauts staring at Phobos from the surface of Mars would notice its oblong, potato-like shape and that it moves quickly against the background stars. Phobos takes only 7 hours, 39 minutes to complete one orbit of Mars. That is so fast, relative to the 24-hour-and-39-minute sol on Mars (the length of time it takes for Mars to complete one rotation), that Phobos rises in the west and sets in the east. Earth's moon, by comparison, rises in the east and sets in the west. The smaller martian moon, Deimos, takes 30 hours, 12 minutes to complete one orbit of Mars. That orbital period is longer than a martian sol, and so Deimos rises, like most solar system moons, in the east and sets in the west. Scientists will use images of the two moons to better map their orbital positions, learn more about their composition, and monitor the presence of nighttime clouds or haze. Spirit took the five images that make up this composite with the panoramic camera, using the camera's broadband filter, which was designed specifically

The Role of Clouds in the Long-Term Habitability of Planets

Science.gov (United States)

Toon, Owen B.; Tolbert, Margaret

2000-01-01

We proposed to conduct theoretical and laboratory investigations of the role that clouds play in the long-term climate history of the Earth and other habitable planets. We made significant progress in the first area we proposed to consider- the properties of carbon dioxide clouds in atmospheres that are rich in carbon dioxide. We submitted a modeling paper on the microphysical properties of the clouds to Icarus showing that such clouds are unlikely to play an important role in the early greenhouses on Earth or Mars. The model was based on lab studies of the nucleation and growth of carbon dioxide. We have also submitted a manuscript describing these lab studies to Icarus. These lab studies are critical not only to the ancient Mars atmosphere, but also to the current one. We also submitted a paper to Nature describing modeling of current Martian CO2 clouds. We will also model the properties of water clouds in the early history of Earth. Early in Earth's history the atmosphere contained no free oxygen. Without oxygen, sulfate aerosols that are currently the dominant cloud nuclei, cannot form. Without such nuclei the cloud structure would have been far different than it is now. We initiated studies of the aerosols on Titan as part of this work. We reported these studies in a short paper on nucleation and in several conferences.

A Subsurface Soil Composition and Physical Properties Experiment to Address Mars Regolith Stratigraphy

Science.gov (United States)

Richter, L.; Sims, M.; Economou, T.; Stoker, C.; Wright, I.; Tokano, T.

2004-01-01

Previous in-situ measurements of soil-like materials on the surface of Mars, in particular during the on-going Mars Exploration Rover missions, have shown complex relationships between composition, exposure to the surface environment, texture, and local rocks. In particular, a diversity in both compositional and physical properties could be established that is interpreted to be diagnostic of the complex geologic history of the martian surface layer. Physical and chemical properties vary laterally and vertically, providing insight into the composition of rocks from which soils derive, and environmental conditions that led to soil formation. They are central to understanding whether habitable environments existed on Mars in the distant past. An instrument the Mole for Soil Compositional Studies and Sampling (MOCSS) - is proposed to allow repeated access to subsurface regolith on Mars to depths of up to 1.5 meters for in-situ measurements of elemental composition and of physical and thermophysical properties, as well as for subsurface sample acquisition. MOCSS is based on the compact PLUTO (PLanetary Underground TOol) Mole system developed for the Beagle 2 lander and incorporates a small X-ray fluorescence spectrometer within the Mole which is a new development. Overall MOCSS mass is approximately 1.4 kilograms. Taken together, the MOCSS science data support to decipher the geologic history at the landing site as compositional and textural stratigraphy if they exist - can be detected at a number of places if the MOCSS were accommodated on a rover such as MSL. Based on uncovered stratigraphy, the regional sequence of depositional and erosional styles can be constrained which has an impact on understanding the ancient history of the Martian near-surface layer, considering estimates of Mars soil production rates of 0.5... 1.0 meters per billion years on the one hand and Mole subsurface access capability of approximately 1.5 meters. An overview of the MOCSS, XRS

Mars Hand Lens Imager (MAHLI) Efforts and Observations at the Rocknest Eolian Sand Shadow in Curiosity's Gale Crater Field Site

Science.gov (United States)

Edgett, K. S.; Yingst, R. A.; Minitti, M. E.; Goetz, W.; Kah, L. C.; Kennedy, M. R.; Lipkaman, L. J.; Jensen, E. H.; Anderson, R. C.; Beegle, L. W.;

Consumption Habits and Humps

DEFF Research Database (Denmark)

Kraft, Holger; Munk, Claus; Seifried, Frank Thomas

2017-01-01

We show that the optimal consumption of an individual over the life cycle can have the hump shape (inverted U-shape) observed empirically if the preferences of the individual exhibit internal habit formation. In the absence of habit formation, an impatient individual would prefer a decreasing...... consumption path over life. However, because of habit formation, a high initial consumption would lead to high required consumption in the future. To cover the future required consumption, wealth is set aside, but the necessary amount decreases with age which allows consumption to increase in the early part...... of life. At some age, the impatience outweighs the habit concerns so that consumption starts to decrease. We derive the optimal consumption strategy in closed form, deduce sufficient conditions for the presence of a consumption hump, and characterize the age at which the hump occurs. Numerical examples...

Consumption Habits and Humps

DEFF Research Database (Denmark)

Kraft, Holger; Munk, Claus; Seifried, Frank Thomas

We show that the optimal consumption of an individual over the life cycle can have the hump shape (inverted U-shape) observed empirically if the preferences of the individual exhibit internal habit formation. In the absence of habit formation, an impatient individual would prefer a decreasing...... consumption path over life. However, because of habit formation, a high initial consumption would lead to high required consumption in the future. To cover the future required consumption, wealth is set aside, but the necessary amount decreases with age which allows consumption to increase in the early part...... of life. At some age, the impatience outweighs the habit concerns so that consumption starts to decrease. We derive the optimal consumption strategy in closed form, deduce sufficient conditions for the presence of a consumption hump, and characterize the age at which the hump occurs. Numerical examples...

The magnetic field of Mars according to data of Mars-3 and Mars-5 space vehicles

International Nuclear Information System (INIS)

Dolginov, Sh.Sh.; Eroshenko, E.G.; Zhuzgov, L.N.

1975-01-01

Magnitograms obtained by the space probe ''Mars-5'' on the evening and day sides as well as those from the ''Mars-3'' obtained earlier suggest the following: In the vicinity of Mars there exists a shock front and its disposition is tracked at various angles to the direction to the sun. Magnetometers have registered a region in space where magnetic field features the properties of a magnetosphere field in its topology and action on plasma. The magnetic field in the region of the ''magnitosphere'' does not change its sign when the interplanetary field does shile in adjacent boundary regions the regular part of the field changes its sign when that of the interplanetary field does. The configuration and dimensions of the ''magnitosphere'' depend on thesolar wind intensity. On the day side (''Mars-3'') the magnitospheric field ceases to be registered at an altitude of 2200km, whereas on the night side (''Mars-5'') the regular field is traced up to 7500-9500km from the planet surface. All the above unambiguously suggests that the planet Mars has its own magnetic field. Under the influence of the solar wind the field takes the characteristic form: it is limited on the day side and elongated on the night one. The topology oif force lines is explicable if one assumes that the axis of the Mars magnetic dipole is inclined to the rotation axis at an abgle of 15-20deg. The northern magnetic pole of the dipole is licated in the northern hemisphere, i.e. the Mars fields in their regularity are opposite to the geomagnetic field. The magnetic moment of the Mars dipole is equal to M=2.5x10 22 Gauss.cm 3 . (author)

Habitable Planets for Man

National Research Council Canada - National Science Library

Dole, Stephen H

2007-01-01

..., and discusses how to search for habitable planets. Interestingly for our time, he also gives an appraisal of the earth as a planet and describes how its habitability would be changed if some of its basic properties were altered...

Planetary habitability: is Earth commonplace in the Milky Way?

Science.gov (United States)

Franck, S; Block, A; von Bloh, W; Bounama, C; Garrido, I; Schellnhuber, H J

2001-10-01

Is there life beyond planet Earth? This is one of the grand enigmas which humankind tries to solve through scientific research. Recent progress in astronomical measurement techniques has confirmed the existence of a multitude of extra-solar planets. On the other hand, enormous efforts are being made to assess the possibility of life on Mars. All these activities have stimulated several investigations about the habitability of cosmic bodies. The habitable zone (HZ) around a given central star is defined as the region within which an Earth-like planet might enjoy the moderate surface temperatures required for advanced life forms. At present, there are several models determining the HZ. One class of models utilises climate constraints for the existence of liquid water on a planetary surface. Another approach is based on an integrated Earth system analysis that relates the boundaries of the HZ to the limits of photosynthetic processes. Within the latter approach, the evolution of the HZ for our solar system over geological time scales is calculated straightforwardly, and a convenient filter can be constructed that picks the candidates for photosynthesis-based life from all the extra-solar planets discovered by novel observational methods. These results can then be used to determine the average number of planets per planetary system that are within the HZ. With the help of a segment of the Drake equation, the number of "Gaias" (i.e. extra-solar terrestrial planets with a globally acting biosphere) is estimated. This leads to the thoroughly educated guess that there should exist half a million Gaias in the Milky Way.

SETI and SEH (Statistical Equation for Habitables)

Science.gov (United States)

Maccone, Claudio

2011-01-01

. The (average) distancebetween any two nearby habitable planets in the Galaxy may be shown to be inversely proportional to the cubic root of NHab. Then, in our approach, this distance becomes a new random variable. We derive the relevant probability density function, apparently previously unknown and dubbed "Maccone distribution" by Paul Davies in 2008. Data Enrichment Principle. It should be noticed that ANY positive number of random variables in the SEH is compatible with the CLT. So, our generalization allows for many more factors to be added in the future as long as more refined scientific knowledge about each factor will be known to the scientists. This capability to make room for more future factors in the SEH we call the "Data Enrichment Principle", and we regard it as the key to more profound future results in the fields of Astrobiology and SETI. A practical example is then given of how our SEH works numerically. We work out in detail the case where each of the ten random variables is uniformly distributed around its own mean value as given by Dole back in 1964 and has an assumed standard deviation of 10%. The conclusion is that the average number of habitable planets in the Galaxy should be around 100 million±200 million, and the average distance in between any couple of nearby habitable planets should be about 88 light years±40 light years. Finally, we match our SEH results against the results of the Statistical Drake Equation that we introduced in our 2008 IAC presentation. As expected, the number of currently communicating ET civilizations in the Galaxy turns out to be much smaller than the number of habitable planets (about 10,000 against 100 million, i.e. one ET civilization out of 10,000 habitable planets). And the average distance between any two nearby habitable planets turns out to be much smaller than the average distance between any two neighboring ET civilizations: 88 light years vs. 2000 light years, respectively. This means an ET average

Mars

CERN Document Server

Payment, Simone

2017-01-01

This curriculum-based, fun, and approachable book offers everything young readers need to know to begin their study of the Red Planet. They will learn about the fundamental aspects of the Mars, including its size, mass, surface features, interior, orbit, and spin. Further, they will learn about the history of the missions to Mars, including the Viking spacecraft and the Curiosity and MAVEN rovers. Finally, readers will learn about why scientists think there's a chance that Mars is or was suitable for life. With stunning imagery from NASA itself, readers will have a front seat-view of the missi

The humanation of Mars

Science.gov (United States)

David, L. W.

Early developments related to human excursions to Mars are examined, taking into account plans considered by von Braun, and the 'ambitious goal of a manned flight to Mars by the end of the century', proposed at the launch of Apollo 11. In response to public reaction, plans for manned flights to Mars in the immediate future were given up, and unmanned reconnaissance of Mars was continued. An investigation is conducted concerning the advantages of manned exploration of Mars in comparison to a study by unmanned space probes, and arguments regarding a justification for interplanetary flight to Mars are discussed. Attention is given to the possibility to consider Mars as a 'back-up' planet for preserving earth life, an international Mars expedition as a world peace project, the role of Mars in connection with resource utilization considerations, and questions of exploration ethics.

Mars Drilling Status

Science.gov (United States)

Mandell, Humboldt, C., Jr.

2002-01-01

This slide presentation reviews the current status of work to explore Mars beneath the surface of planet. One of the objective of this work is to enable further exploration of Mars by humans. One of the requirements for this is to find water on Mars. The presences of water is critical for Human Exploration and a permanent presence on Mars. If water is present beneath the surface it is the best chance of finding life on Mars. The presentation includes a timeline showing the robotic missions, those that have already been on Mars, and planned missions, an explanation of why do we want to drill on Mars, and some of the challenges, Also include are reviews of a missions that would drill 200 and 4,000 to 6,000 meters into the Martian bedrock, and a overview description of the drill. There is a view of some places where we have hopes of finding water.

Host Star Evolution for Planet Habitability.

Science.gov (United States)

Gallet, Florian; Charbonnel, Corinne; Amard, Louis

2016-11-01

With about 2000 exoplanets discovered within a large range of different configurations of distance from the star, size, mass, and atmospheric conditions, the concept of habitability cannot rely only on the stellar effective temperature anymore. In addition to the natural evolution of habitability with the intrinsic stellar parameters, tidal, magnetic, and atmospheric interactions are believed to have strong impact on the relative position of the planets inside the so-called habitable zone. Moreover, the notion of habitability itself strongly depends on the definition we give to the term "habitable". The aim of this contribution is to provide a global and up-to-date overview of the work done during the last few years about the description and the modelling of the habitability, and to present the physical processes currently includes in this description.

Mars ISRU for Production of Mission Critical Consumables - Options, Recent Studies, and Current State of the Art

Science.gov (United States)

Sanders, G. B.; Paz, A.; Oryshchyn, L.; Araghi, K.; Muscatello, A.; Linne, D.; Kleinhenz, J.; Peters, T.

2015-01-01

In 1978, a ground breaking paper titled, "Feasibility of Rocket Propellant Production on Mars" by Ash, Dowler, and Varsi discussed how ascent propellants could be manufactured on the Mars surface from carbon dioxide collected from the atmosphere to reduce launch mass. Since then, the concept of making mission critical consumables such as propellants, fuel cell reactants, and life support consumables from local resources, commonly known as In-Situ Resource Utilization (ISRU), for robotic and human missions to Mars has been studied many times. In the late 1990's, NASA initiated a series of Mars Human Design Reference Missions (DRMs), the first of which was released in 1997. These studies primarily focused on evaluating the impact of making propellants on Mars for crew ascent to Mars orbit, but creating large caches of life support consumables (water & oxygen) as a backup for regenerative life support systems for long-duration surface stays (>500 days) was also considered in Mars DRM 3.0. Until science data from the Mars Odyssey orbiter and subsequent robotic missions revealed that water may be widely accessable across the surface of Mars, prior Mars ISRU studies were limited to processing Mars atmospheric resources (carbon dioxide, nitrogen, argon, oxygen, and water vapor). In December 2007, NASA completed the Mars Human Design Reference Architecture (DRA) 5.0 study which considered water on Mars as a potential resource for the first time in a human mission architecture. While knowledge of both water resources on Mars and the hardware required to excavate and extract the water were very preliminary, the study concluded that a significant reduction in mass and significant enhancements to the mission architecture were possible if Mars water resources were utilized. Two subsequent Mars ISRU studies aimed at reexamining ISRU technologies, processing options, and advancements in the state-of-the-art since 2007 and to better understand the volume and packaging associated

Clay mineral formation under oxidized conditions and implications for paleoenvironments and organic preservation on Mars.

Science.gov (United States)

Gainey, Seth R; Hausrath, Elisabeth M; Adcock, Christopher T; Tschauner, Oliver; Hurowitz, Joel A; Ehlmann, Bethany L; Xiao, Yuming; Bartlett, Courtney L

2017-11-01

Clay mineral-bearing locations have been targeted for martian exploration as potentially habitable environments and as possible repositories for the preservation of organic matter. Although organic matter has been detected at Gale Crater, Mars, its concentrations are lower than expected from meteoritic and indigenous igneous and hydrothermal reduced carbon. We conducted synthesis experiments motivated by the hypothesis that some clay mineral formation may have occurred under oxidized conditions conducive to the destruction of organics. Previous work has suggested that anoxic and/or reducing conditions are needed to synthesize the Fe-rich clay mineral nontronite at low temperatures. In contrast, our experiments demonstrated the rapid formation of Fe-rich clay minerals of variable crystallinity from aqueous Fe 3+ with small amounts of aqueous Mg 2+ . Our results suggest that Fe-rich clay minerals such as nontronite can form rapidly under oxidized conditions, which could help explain low concentrations of organics within some smectite-containing rocks or sediments on Mars.

Clay mineral formation under oxidized conditions and implications for paleoenvironments and organic preservation on Mars

Energy Technology Data Exchange (ETDEWEB)

Gainey, Seth R.; Hausrath, Elisabeth M.; Adcock, Christopher T.; Tschauner, Oliver; Hurowitz, Joel A.; Ehlmann, Bethany L.; Xiao, Yuming; Bartlett, Courtney L. (CIW); (UNLV); (CIT); (SBU)

2017-11-01

Clay mineral-bearing locations have been targeted for martian exploration as potentially habitable environments and as possible repositories for the preservation of organic matter. Although organic matter has been detected at Gale Crater, Mars, its concentrations are lower than expected from meteoritic and indigenous igneous and hydrothermal reduced carbon. We conducted synthesis experiments motivated by the hypothesis that some clay mineral formation may have occurred under oxidized conditions conducive to the destruction of organics. Previous work has suggested that anoxic and/or reducing conditions are needed to synthesize the Fe-rich clay mineral nontronite at low temperatures. In contrast, our experiments demonstrated the rapid formation of Fe-rich clay minerals of variable crystallinity from aqueous Fe3+ with small amounts of aqueous Mg2+. Our results suggest that Fe-rich clay minerals such as nontronite can form rapidly under oxidized conditions, which could help explain low concentrations of organics within some smectite-containing rocks or sediments on Mars.

Building Virtual Mars

Science.gov (United States)

Abercrombie, S. P.; Menzies, A.; Goddard, C.

2017-12-01

Virtual and augmented reality enable scientists to visualize environments that are very difficult, or even impossible to visit, such as the surface of Mars. A useful immersive visualization begins with a high quality reconstruction of the environment under study. This presentation will discuss a photogrammetry pipeline developed at the Jet Propulsion Laboratory to reconstruct 3D models of the surface of Mars using stereo images sent back to Earth by the Curiosity Mars rover. The resulting models are used to support a virtual reality tool (OnSight) that allows scientists and engineers to visualize the surface of Mars as if they were standing on the red planet. Images of Mars present challenges to existing scene reconstruction solutions. Surface images of Mars are sparse with minimal overlap, and are often taken from extremely different viewpoints. In addition, the specialized cameras used by Mars rovers are significantly different than consumer cameras, and GPS localization data is not available on Mars. This presentation will discuss scene reconstruction with an emphasis on coping with limited input data, and on creating models suitable for rendering in virtual reality at high frame rate.

Six habits to enhance MET performance under stress: A discussion paper reviewing team mechanisms for improved patient outcomes.

Science.gov (United States)

Fein, Erich C; Mackie, Benjamin; Chernyak-Hai, Lily; O'Quinn, C Richard V; Ahmed, Ezaz

2016-05-01

Effective team decision making has the potential to improve the quality of health care outcomes. Medical Emergency Teams (METs), a specific type of team led by either critical care nurses or physicians, must respond to and improve the outcomes of deteriorating patients. METs routinely make decisions under conditions of uncertainty and suboptimal care outcomes still occur. In response, the development and use of Shared Mental Models (SMMs), which have been shown to promote higher team performance under stress, may enhance patient outcomes. This discussion paper specifically focuses on the development and use of SMMs in the context of METs. Within this process, the psychological mechanisms promoting enhanced team performance are examined and the utility of this model is discussed through the narrative of six habits applied to MET interactions. A two stage, reciprocal model of both nonanalytic decision making within the acute care environment and analytic decision making during reflective action learning was developed. These habits are explored within the context of a MET, illustrating how applying SMMs and action learning processes may enhance team-based problem solving under stress. Based on this model, we make recommendations to enhance MET decision making under stress. It is suggested that the corresponding habits embedded within this model could be imparted to MET members and tested by health care researchers to assess the efficacy of this integrated decision making approach in respect to enhanced team performance and patient outcomes. Copyright © 2015. Published by Elsevier Ltd.

MARS CODE MANUAL VOLUME V: Models and Correlations

International Nuclear Information System (INIS)

Chung, Bub Dong; Bae, Sung Won; Lee, Seung Wook; Yoon, Churl; Hwang, Moon Kyu; Kim, Kyung Doo; Jeong, Jae Jun

2010-02-01

Korea Advanced Energy Research Institute (KAERI) conceived and started the development of MARS code with the main objective of producing a state-of-the-art realistic thermal hydraulic systems analysis code with multi-dimensional analysis capability. MARS achieves this objective by very tightly integrating the one dimensional RELAP5/MOD3 with the multi-dimensional COBRA-TF codes. The method of integration of the two codes is based on the dynamic link library techniques, and the system pressure equation matrices of both codes are implicitly integrated and solved simultaneously. In addition, the Equation-Of-State (EOS) for the light water was unified by replacing the EOS of COBRA-TF by that of the RELAP5. This models and correlations manual provides a complete list of detailed information of the thermal-hydraulic models used in MARS, so that this report would be very useful for the code users. The overall structure of the manual is modeled on the structure of the RELAP5 and as such the layout of the manual is very similar to that of the RELAP. This similitude to RELAP5 input is intentional as this input scheme will allow minimum modification between the inputs of RELAP5 and MARS3.1. MARS3.1 development team would like to express its appreciation to the RELAP5 Development Team and the USNRC for making this manual possible

Effect of Sulfur Concentration and PH Conditions on Akaganeite Formation: Understanding Akaganeite Formation Conditions in Yellowknife Bay, Gale Crater, Mars

Science.gov (United States)

Fox, A.; Peretyazhko, T.; Sutter, B.; Niles, P.; Ming, D. W.; Morris, R. V.

2015-01-01

The Chemistry and Mineralogy Instrument (CHEMIN) on board the Mars Science Laboratory (MSL) Curiosity Rover identified minor amounts of akaganeite (beta-FeOOH) at Yellowknife Bay, Mars. There is also evidence for akaganeite at other localities on Mars from the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM). Akaganeite is an iron(III) hydroxide with a hollandite- like structure and Cl in its tunnels. Terrestrial akaganeite usually forms in Cl-rich environments under acidic, oxidizing conditions. Previous studies of akaganeite have revealed that akaganeite formation is affected by the presence of sulfate (hereafter denoted as S. The prediction of circumneutral pH coupled with the detection of S at Yellowknife Bay dictate that work is needed to determine how S and pH together affect akaganeite formation. The goal of this work is to study how changes in both S concentration and pH influence akaganeite precipitation. Akaganeite formation was investigated at S/Cl molar ratios of 0, 0.017, 0.083, 0.17 and 0.33 at pH 1.5, 2, and 4. Results are anticipated to provide combined S concentration and pH constraints on akaganeite formation in Yellowknife Bay and elsewhere on Mars. Knowledge of solution pH and S concentrations can be utilized in understanding microbial habitability potential on the Martian surface.

Constraining Exoplanet Habitability with HabEx

Science.gov (United States)

Robinson, Tyler

2018-01-01

The Habitable Exoplanet Imaging mission, or HabEx, is one of four flagship mission concepts currently under study for the upcoming 2020 Decadal Survey of Astronomy and Astrophysics. The broad goal of HabEx will be to image and study small, rocky planets in the Habitable Zones of nearby stars. Additionally, HabEx will pursue a range of other astrophysical investigations, including the characterization of non-habitable exoplanets and detailed observations of stars and galaxies. Critical to the capability of HabEx to understand Habitable Zone exoplanets will be its ability to search for signs of surface liquid water (i.e., habitability) and an active biosphere. Photometry and moderate resolution spectroscopy, spanning the ultraviolet through near-infrared spectral ranges, will enable constraints on key habitability-related atmospheric species and properties (e.g., surface pressure). In this poster, we will discuss approaches to detecting signs of habitability in reflected-light observations of rocky exoplanets. We will also present initial results for modeling experiments aimed at demonstrating the capabilities of HabEx to study and understand Earth-like worlds around other stars.

Healthy eating habits protect against temptations.

Science.gov (United States)

Lin, Pei-Ying; Wood, Wendy; Monterosso, John

2016-08-01

Can healthy food-choice habits protect people against temptations of consuming large portion sizes and unhealthy foods? In two studies, we show that the answer is yes, good habits serve this protective role, at least in contexts in which people are not deliberating and thus fall back on habitual responses. In the first study, participants trained with unhealthy habits to approach eating chocolate, but not those trained with healthy habits, succumbed to temptation and ate more chocolates when their self-control resources were depleted. Study 2 extended and clarified these findings by demonstrating the role of environmental cues in eliciting healthy habits when self-control resources are depleted. Participants who had been trained to choose carrots habitually to a pictorial stimulus (i.e., habit cue) subsequently resisted choosing M&Ms as long as the cue was present. This effect of habit cues on healthy food choices suggests the usefulness of manipulating such cues as a means of meeting self-regulatory goals such as portion control. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Regulatory Small RNA MarS Supports Virulence of Streptococcus pyogenes.

Science.gov (United States)

Pappesch, Roberto; Warnke, Philipp; Mikkat, Stefan; Normann, Jana; Wisniewska-Kucper, Aleksandra; Huschka, Franziska; Wittmann, Maja; Khani, Afsaneh; Schwengers, Oliver; Oehmcke-Hecht, Sonja; Hain, Torsten; Kreikemeyer, Bernd; Patenge, Nadja

2017-09-25

Small regulatory RNAs (sRNAs) play a role in the control of bacterial virulence gene expression. In this study, we investigated an sRNA that was identified in Streptococcus pyogenes (group A Streptococcus, GAS) but is conserved throughout various streptococci. In a deletion strain, expression of mga, the gene encoding the multiple virulence gene regulator, was reduced. Accordingly, transcript and proteome analyses revealed decreased expression of several Mga-activated genes. Therefore, and because the sRNA was shown to interact with the 5' UTR of the mga transcript in a gel-shift assay, we designated it MarS for m ga-activating regulatory sRNA. Down-regulation of important virulence factors, including the antiphagocytic M-protein, led to increased susceptibility of the deletion strain to phagocytosis and reduced adherence to human keratinocytes. In a mouse infection model, the marS deletion mutant showed reduced dissemination to the liver, kidney, and spleen. Additionally, deletion of marS led to increased tolerance towards oxidative stress. Our in vitro and in vivo results indicate a modulating effect of MarS on virulence gene expression and on the pathogenic potential of GAS.

[Significance of bad habits in orthodontics].

Science.gov (United States)

Tarján, Ildikó

2002-08-01

The author is concerned with the etiological role of bad habits in the development. Disturbances caused by pacifier habits, finger sucking, various forms of swallowing habits and their therapeutical possibilities are discussed. The role of mouth breathing, nail biting, bruxism and self-mutilation in development of anomalies and their therapy are also mentioned. The attention is called to the fact that dentists have responsibility and task to diagnose as early as can be the oral bad habits and that the adequate therapy in time in co-operation with other specialists helping the child get out of bad habits, preventing the development of severe anomaly.

Food Habits and Future Time: An Exploratory Study of Age-Appropriate Food Habits Among the Elderly.

Science.gov (United States)

Shifflett, Peggy A.; McIntosh, William A.

1987-01-01

Examined future time perspective and its association with change in food habits among elderly persons (N=805). Findings suggest that the elderly change food habits and that there is an association of positive or negative food habit changes with a positive or negative future time perspective. (Author/NB)

Less is more : The effect of multiple implementation intentions targeting unhealthy snacking habits

NARCIS (Netherlands)

Verhoeven, A.A.C.; Adriaanse, M.A.; de Ridder, D.T.D.; de Vet, E.; Fennis, B.M.

Implementation intentions have been shown to effectively change counter-intentional habits. Research has, however, almost solely been concerned with the effectiveness of a single plan. In the present research, we investigated the behavioral and cognitive implications of making multiple

Less is more: The effect of multiple implementation intentions targeting unhealthy snacking habits

NARCIS (Netherlands)

Verhoeven, A.A.C.; Adriaanse, M.A.; Ridder, de D.T.D.; Vet, de E.W.M.L.; Fennis, B.M.

2013-01-01

Implementation intentions have been shown to effectively change counter-intentional habits. Research has, however, almost solely been concerned with the effectiveness of a single plan. In the present research, we investigated the behavioral and cognitive implications of making multiple

Searching for habitable exoplanets by using combined microlensing and radial velocity facilities

International Nuclear Information System (INIS)

Joergensen, Uffe Graae

2008-01-01

The habitable planetary regime, where life as we know it from the Earth in principle can exist, has long been among the technically most difficult to search for the existence of exoplanets. It spans the inner and outer orbital range, where liquid water in principle can exist on a planetary surface (the habitable zone), and the planetary mass range from the lowest mass where an atmosphere is bound over biological timescales to the upper mass limit where a nebula gas-collapse transforms a solid planet into a gas planet. With a prober equipment, microlensing is sensitive to this regime for most stellar types, including solar-type stars, while the radial velocity technique complements the detection regime by being sensitive to such planets around the lowest mass stars. By combining microlensing with radial velocity measurements, it is possible to cover the complete habitable region from the ground. I outline here the theory that in principle will make it possible to perform an efficient survey throughout the habitable regime of the most common types of stars in our galaxy over the next few years, and describe how it can be done in practise for a relatively low cost

The power of habits : Unhealthy snacking behaviour is primarily predicted by habit strength

NARCIS (Netherlands)

Verhoeven, A.A.C.; Adriaanse, M.A.; Evers, C.; de Ridder, D.T.D.

2012-01-01

Objective. Although increasing evidence shows the importance of habits in explaining health behaviour, many studies still rely solely on predictors that emphasize the role of conscious intentions. The present study was designed to test the importance of habit strength in explaining unhealthy

Mars

CERN Document Server

Day, Trevor

2006-01-01

Discusses the fundamental facts concerning this mysterious planet, including its mass, size, and atmosphere, as well as the various missions that helped planetary scientists document the geological history of Mars. This volume also describes Mars'' seasons with their surface effects on the planet and how they have changed over time.

Disorders of compulsivity: a common bias towards learning habits.

Science.gov (United States)

Voon, V; Derbyshire, K; Rück, C; Irvine, M A; Worbe, Y; Enander, J; Schreiber, L R N; Gillan, C; Fineberg, N A; Sahakian, B J; Robbins, T W; Harrison, N A; Wood, J; Daw, N D; Dayan, P; Grant, J E; Bullmore, E T

2015-03-01

Why do we repeat choices that we know are bad for us? Decision making is characterized by the parallel engagement of two distinct systems, goal-directed and habitual, thought to arise from two computational learning mechanisms, model-based and model-free. The habitual system is a candidate source of pathological fixedness. Using a decision task that measures the contribution to learning of either mechanism, we show a bias towards model-free (habit) acquisition in disorders involving both natural (binge eating) and artificial (methamphetamine) rewards, and obsessive-compulsive disorder. This favoring of model-free learning may underlie the repetitive behaviors that ultimately dominate in these disorders. Further, we show that the habit formation bias is associated with lower gray matter volumes in caudate and medial orbitofrontal cortex. Our findings suggest that the dysfunction in a common neurocomputational mechanism may underlie diverse disorders involving compulsion.

Associations between food consumption habits with meal intake behaviour in Spanish adults.

Science.gov (United States)

Keller, Kristin; Rodríguez López, Santiago; Carmenate Moreno, M Margarita; Acevedo Cantero, Paula

2014-12-01

The aim of the present study is to explore the contribution of different types of meal intake behaviour on a healthy diet and seeks to find associations with food consumption habits. A cross-sectional survey with data from 1332 Spanish adults aged between 20 and 79 years was conducted. The survey was carried out during the cardiovascular health event 'Semanas del Corazon 2008' in four Spanish cities. Several food consumption habits such as the recommended intake of fruits, vegetables, milk and dairy products, as well as the regular consumption of fatty and salty food and ready-made meals, were used as dependent variables in logistic regression. We evaluated different meal intake behaviour such as the type of meals, snacking, and drinks taken with a meal. Our survey revealed that snacking is positively associated with the regular consumption of salty and fatty food, and having sugary drinks with meals was positively associated with the regular consumption of ready-made meals. Having a forenoon meal is positively associated with the consumption of two or more portions of milk and dairy products and vegetables, and taking an afternoon meal with the recommended intake of milk and dairy products and fruits. Drinking water during a meal increases the probability of consuming two or more portions of fruits and vegetables. Our results enhance the understanding of the contribution that meal intake behaviour makes to a healthy diet based on food consumption habits. This work provides an insight into eating behaviour and would make a useful contribution to interventions aimed at promoting healthier eating habits. Copyright © 2014 Elsevier Ltd. All rights reserved.

Organizing physics teacher professional education around productive habit development: A way to meet reform challenges

Directory of Open Access Journals (Sweden)

Eugenia Etkina

2017-01-01

Full Text Available Extant literature on teacher preparation suggests that preservice teachers learn best when they are immersed in a community that allows them to develop dispositions, knowledge, and practical skills and share with the community a strong vision of what good teaching entails. However, even if the requisite dispositions, knowledge, and skills in pursuing the shared vision of good teaching are developed, the professional demands on a teacher’s time are so great out of, and so complex during class time that if every decision requires multiple considerations and deliberations with oneself, the productive decisions might not materialize. We argue that the link between intentional decision making and actual teaching practice are teacher’s habits (spontaneous responses to situational cues. Teachers unavoidably develop habits with practical experience and under the influence of knowledge and belief structures that in many ways condition the responses of teachers in their practical work. To steer new teachers away from developing unproductive habits directed towards “survival” instead of student learning, we propose that teacher preparation programs (e.g., in physics strive to develop in preservice teachers strong habits of mind and practice that will serve as an underlying support structure for beginning teachers. We provide examples of physics teacher habits that are to be developed during the program, propose mechanisms for the development of such habits, and outline possible future research agendas around habits.

Organizing physics teacher professional education around productive habit development: A way to meet reform challenges

Science.gov (United States)

Etkina, Eugenia; Gregorcic, Bor; Vokos, Stamatis

2017-06-01

Extant literature on teacher preparation suggests that preservice teachers learn best when they are immersed in a community that allows them to develop dispositions, knowledge, and practical skills and share with the community a strong vision of what good teaching entails. However, even if the requisite dispositions, knowledge, and skills in pursuing the shared vision of good teaching are developed, the professional demands on a teacher's time are so great out of, and so complex during class time that if every decision requires multiple considerations and deliberations with oneself, the productive decisions might not materialize. We argue that the link between intentional decision making and actual teaching practice are teacher's habits (spontaneous responses to situational cues). Teachers unavoidably develop habits with practical experience and under the influence of knowledge and belief structures that in many ways condition the responses of teachers in their practical work. To steer new teachers away from developing unproductive habits directed towards "survival" instead of student learning, we propose that teacher preparation programs (e.g., in physics) strive to develop in preservice teachers strong habits of mind and practice that will serve as an underlying support structure for beginning teachers. We provide examples of physics teacher habits that are to be developed during the program, propose mechanisms for the development of such habits, and outline possible future research agendas around habits.

Health Habit: A Concept Analysis.

Science.gov (United States)

Opalinski, Andra S; Weglicki, Linda S; Gropper, Sareen S

2018-01-01

The aim of this article is to provide clarity of the concept of health habit. Using Walker and Avant's (1983; 2010) method for conducting a concept analysis, the authors identify the attributes and characteristics of health habit, its theoretical and practical application to nursing, and sample cases to further illustrate the concept. Empirical and conceptual literature was used to inform this concept analysis. Articles and one book from 1977 to 2014 were reviewed from PsycINFO, Medline, Cumulative Index to Nursing Health Literature (CINAHL), Science Direct, EBSCOhost and Web of Science. Offering a clear definition and conceptual model of health habit provide the foundation to identify/develop appropriate measures of the concept and guide further investigation of understanding the development and sustainability of healthy habits. Additional research is needed to test the conceptual relationships between health habits and outcome variables as they apply to different groups across the age continuum. © 2017 Wiley Periodicals, Inc.

Geology of Mars

International Nuclear Information System (INIS)

Soderblom, L.A.

1988-01-01

The geology of Mars and the results of the Mariner 4, 6/7, and 9 missions and the Viking mission are reviewed. The Mars chronology and geologic modification are examined, including chronological models for the inactive planet, the active planet, and crater flux. The importance of surface materials is discussed and a multispectral map of Mars is presented. Suggestions are given for further studies of the geology of Mars using the Viking data. 5 references

Permanent Habitats in Earth-Sol/Mars-Sol Orbit Positions

Science.gov (United States)

Greenspon, J.

Project Outpost is a manned Earth-Sol/Mars-Sol platform that enables permanent occupation in deep space. In order to develop the program elements for this complex mission, Project Outpost will rely primarily on existing/nearterm technology and hardware for the construction of its components. For the purposes of this study, four mission requirements are considered: 1. Outpost - Man's 1st purpose-produced effort of space engineering, in which astructure is developed/constructed in an environment completely alien to currentpractices for EVA guidelines. 2. Newton - a concept study developed at StarGate Research, for the development ofa modified Hohmann personnel orbital transport operating between Earth andMars. Newton would serve as the primary crew delivery apparatus throughrepeatable transfer scheduling for all Earth-Lpoint-Mars activities. Thispermanent "transit system" would establish the foundations for Solar systemcolonization. 3. Cruis - a concept study developed at StarGate Research, for the development of amodified Hohmann cargo orbital transport operating between Earth and Mars.Cruis would serve as the primary equipment delivery apparatus throughrepeatable transfer scheduling for all Earth-Lpoint-Mars activities. Thispermanent "transit system" would establish the foundations for Solar systemcolonization, and 4. Ares/Diana - a more conventional space platform configuration for Lunar andMars orbit is included as a construction baseline. The operations of these assetsare supported, and used for the support, of the outpost. Outpost would be constructed over a 27-year period of launch opportunities into Earth-Sol or Mars-Sol Lagrange orbit (E-S/M-S L1, 4 or 5). The outpost consists of an operations core with a self-contained power generation ability, a docking and maintenance structure, a Scientific Research complex and a Habitation Section. After achieving initial activation, the core will provide the support and energy required to operate the outpost in a 365

Mars 2.2 code manual: input requirements

International Nuclear Information System (INIS)

Chung, Bub Dong; Lee, Won Jae; Jeong, Jae Jun; Lee, Young Jin; Hwang, Moon Kyu; Kim, Kyung Doo; Lee, Seung Wook; Bae, Sung Won

2003-07-01

Korea Advanced Energy Research Institute (KAERI) conceived and started the development of MARS code with the main objective of producing a state-of-the-art realistic thermal hydraulic systems analysis code with multi-dimensional analysis capability. MARS achieves this objective by very tightly integrating the one dimensional RELAP5/MOD3 with the multi-dimensional COBRA-TF codes. The method of integration of the two codes is based on the dynamic link library techniques, and the system pressure equation matrices of both codes are implicitly integrated and solved simultaneously. In addition, the Equation-of-State (EOS) for the light water was unified by replacing the EOS of COBRA-TF by that of the RELAP5. This input manual provides a complete list of input required to run MARS. The manual is divided largely into two parts, namely, the one-dimensional part and the multi-dimensional part. The inputs for auxiliary parts such as minor edit requests and graph formatting inputs are shared by the two parts and as such mixed input is possible. The overall structure of the input is modeled on the structure of the RELAP5 and as such the layout of the manual is very similar to that of the RELAP. This similitude to RELAP5 input is intentional as this input scheme will allow minimum modification between the inputs of RELAP5 and MARS. MARS development team would like to express its appreciation to the RELAP5 Development Team and the USNRC for making this manual possible

MARS code manual volume II: input requirements

International Nuclear Information System (INIS)

Chung, Bub Dong; Kim, Kyung Doo; Bae, Sung Won; Jeong, Jae Jun; Lee, Seung Wook; Hwang, Moon Kyu

2010-02-01

Korea Advanced Energy Research Institute (KAERI) conceived and started the development of MARS code with the main objective of producing a state-of-the-art realistic thermal hydraulic systems analysis code with multi-dimensional analysis capability. MARS achieves this objective by very tightly integrating the one dimensional RELAP5/MOD3 with the multi-dimensional COBRA-TF codes. The method of integration of the two codes is based on the dynamic link library techniques, and the system pressure equation matrices of both codes are implicitly integrated and solved simultaneously. In addition, the Equation-Of-State (EOS) for the light water was unified by replacing the EOS of COBRA-TF by that of the RELAP5. This input manual provides a complete list of input required to run MARS. The manual is divided largely into two parts, namely, the one-dimensional part and the multi-dimensional part. The inputs for auxiliary parts such as minor edit requests and graph formatting inputs are shared by the two parts and as such mixed input is possible. The overall structure of the input is modeled on the structure of the RELAP5 and as such the layout of the manual is very similar to that of the RELAP. This similitude to RELAP5 input is intentional as this input scheme will allow minimum modification between the inputs of RELAP5 and MARS3.1. MARS3.1 development team would like to express its appreciation to the RELAP5 Development Team and the USNRC for making this manual possible

Mars for Earthlings: an analog approach to Mars in undergraduate education.

Science.gov (United States)

Chan, Marjorie; Kahmann-Robinson, Julia

2014-01-01

Mars for Earthlings (MFE) is a terrestrial Earth analog pedagogical approach to teaching undergraduate geology, planetary science, and astrobiology. MFE utilizes Earth analogs to teach Mars planetary concepts, with a foundational backbone in Earth science principles. The field of planetary science is rapidly changing with new technologies and higher-resolution data sets. Thus, it is increasingly important to understand geological concepts and processes for interpreting Mars data. MFE curriculum is topically driven to facilitate easy integration of content into new or existing courses. The Earth-Mars systems approach explores planetary origins, Mars missions, rocks and minerals, active driving forces/tectonics, surface sculpting processes, astrobiology, future explorations, and hot topics in an inquiry-driven environment. Curriculum leverages heavily upon multimedia resources, software programs such as Google Mars and JMARS, as well as NASA mission data such as THEMIS, HiRISE, CRISM, and rover images. Two years of MFE class evaluation data suggest that science literacy and general interest in Mars geology and astrobiology topics increased after participation in the MFE curriculum. Students also used newly developed skills to create a Mars mission team presentation. The MFE curriculum, learning modules, and resources are available online at http://serc.carleton.edu/marsforearthlings/index.html.

Habitable worlds with no signs of life

OpenAIRE

Cockell, Charles S.

2014-01-01

‘Most habitable worlds in the cosmos will have no remotely detectable signs of life’ is proposed as a biological hypothesis to be tested in the study of exoplanets. Habitable planets could be discovered elsewhere in the Universe, yet there are many hypothetical scenarios whereby the search for life on them could yield negative results. Scenarios for habitable worlds with no remotely detectable signatures of life include: planets that are habitable, but have no biosphere (Uninhabited Habitable...

Is Mars Sample Return Required Prior to Sending Humans to Mars?

Science.gov (United States)

Carr, Michael; Abell, Paul; Allwood, Abigail; Baker, John; Barnes, Jeff; Bass, Deborah; Beaty, David; Boston, Penny; Brinkerhoff, Will; Budney, Charles;

Oral Habits That Cause Malocclusion Problems

OpenAIRE

Joelijanto, Rudy

2012-01-01

Oral habits that place pressure on the teeth may slowly move the teeth out of place. The aim of this study was to review the literature for articles referring the most common oral habits that cause malocclusion. The oral bad habits that cause malocclussion problems include: Thumb sucking, It is a normal habit for babies, but causes serious orthodontic problems if it continues long after the eruption of permanent teeth. Prolonged thumb sucking can create crowded, crooked teeth, or bite problem...

Habit formation, work ethics, and technological progress

OpenAIRE

Faria, João Ricardo; León-Ledesma, Miguel A.

2002-01-01

Work ethics affects labor supply. This idea is modeled assuming that work is habit forming. This paper introduces working habits in a neoclassical growth model and compares its outcomes with a model without habit formation. In addition, it analyzes the impact of different forms of technical progress. The findings are that i) labor supply in the habit formation case is higher than in the neoclassical case; ii) unlike in the neoclassical case, labor supply in the presence of habit formation wil...

Breaking bad habits by improving executive function in individuals with obesity.

Science.gov (United States)

Allom, Vanessa; Mullan, Barbara; Smith, Evelyn; Hay, Phillipa; Raman, Jayanthi

2018-04-16

Two primary factors that contribute to obesity are unhealthy eating and sedentary behavior. These behaviors are particularly difficult to change in the long-term because they are often enacted habitually. Cognitive Remediation Therapy has been modified and applied to the treatment of obesity (CRT-O) with preliminary results of a randomized controlled trial demonstrating significant weight loss and improvements in executive function. The objective of this study was to conduct a secondary data analysis of the CRT-O trial to evaluate whether CRT-O reduces unhealthy habits that contribute to obesity via improvements in executive function. Eighty participants with obesity were randomized to CRT-O or control. Measures of executive function (Wisconsin Card Sort Task and Trail Making Task) and unhealthy eating and sedentary behavior habits were administered at baseline, post-intervention and at 3 month follow-up. Participants receiving CRT-O demonstrated improvements in both measures of executive function and reductions in both unhealthy habit outcomes compared to control. Mediation analyses revealed that change in one element of executive function performance (Wisconsin Card Sort Task perseverance errors) mediated the effect of CRT-O on changes in both habit outcomes. These results suggest that the effectiveness of CRT-O may result from the disruption of unhealthy habits made possible by improvements in executive function. In particular, it appears that cognitive flexibility, as measured by the Wisconsin Card Sort task, is a key mechanism in this process. Improving cognitive flexibility may enable individuals to capitalise on interruptions in unhealthy habits by adjusting their behavior in line with their weight loss goals rather than persisting with an unhealthy choice. The RCT was registered with the Australian New Zealand Registry of Clinical Trials (trial id: ACTRN12613000537752 ).

Influence of temperature on δ-hydride habit plane in α-Zirconium

International Nuclear Information System (INIS)

Singh, R. N.; Stahle, P.; Banerjee, S.; Ristmanaa, Matti; Sauramd, K.

2008-01-01

Dilute Zr-alloy with hcp α-Zr as major phase is used as pressure boundary for hot coolant in CANDU, PHWR and RBMK reactors. Hydrogen / deuterium ingress during service makes the pressure boundary components like pressure tubes of the aforementioned reactors susceptible to hydride embrittlement. Hydride acquires plate shaped morphology and the broad face of the hydride plate coincides with certain crystallographic plane of α-Zr crystal, which is called habit plane. Hydride plate oriented normal to tensile stress significantly increases the degree of embrittlement. Thus key to mitigating the damage due to hydride embrittlement is to avoid the formation of hydride plates normal to tensile stress. Two different theoretical approaches are used to determine the habit plane of precipitates viz., geometrical and solid mechanics. For the geometrical approach invariant plane and invariant-line criteria have been applied successfully and for the solid mechanics approach strain energy minimization criteria have been used successfully. Solid mechanics approach using strain energy computed by FEM technique has been applied to hydride precipitation in Zr-alloys, but the emphasis has been to understand the solvus hysteresis. The objective of the present investigation is to predict the habit plane of δ-hydride precipitating in α-Zr at 25, 300, 400 and 450 .deg. C. using strain energy minimization technique. The δ-hydride phase is modeled to undergo isotropic elastic and plastic deformation. The α-Zr phase was modeled to undergo transverse isotropic elastic deformation. Both isotropic plastic and transverse isotropic plastic deformations of α-Zr were considered. Further, both perfect and linear work-hardening plastic behaviors were considered. Accommodation strain energy of δ-hydrides forming in α-Zr crystal was computed using initial strain method as a function of hydride nuclei orientation. Hydride was modeled as disk with circular edge. The simulation was carried out

Constructing an Educational Mars Simulation

Science.gov (United States)

Henke, Stephen A.

2004-01-01

January 14th 2004, President George Bush announces his plans to catalyst the space program into a new era of space exploration and discovery. His vision encompasses a robotics program to explore our solar system, a return to the moon, the human exploration of Mars, and to promote international prosperity towards our endeavors. We at NASA now have the task of constructing this vision in a very real timeframe. I have been chosen to begin phase 1 of making this vision a reality. I will be working on creating an Educational Mars Simulation of human exploration of Mars to stimulate interest and involvement with the project from investors and the community. GRC s Computer Services Division (CSD) in collaboration with the Office of Education Programs will be designing models, constructing terrain, and programming this simulation to create a realistic portrayal of human exploration on mars. With recent and past technological breakthroughs in computing, my primary goal can be accomplished with only the aid of 3-4 software packages. Lightwave 3D is the modeling package we have selected to use for the creation of our digital objects. This includes a Mars pressurized rover, rover cockpit, landscape/terrain, and habitat. Once we have the models completed they need textured so Photoshop and Macromedia Fireworks are handy for bringing these objects to life. Before directly importing all of this data into a simulation environment, it is necessary to first render a stunning animation of the desired final product. This animation with represent what we hope to capture out of the simulation and it will include all of the accessories like ray-tracing, fog effects, shadows, anti-aliasing, particle effects, volumetric lighting, and lens flares. Adobe Premier will more than likely be used for video editing and adding ambient noises and music. Lastly, V-Tree is the real-time 3D graphics engine which will facilitate our realistic simulation. Additional information is included in the

Mars Navigator: An Interactive Multimedia Program about Mars, Aerospace Engineering, Astronomy, and the JPL Mars Missions. [CD-ROM

Science.gov (United States)

Gramoll, Kurt

This CD-ROM introduces basic astronomy and aerospace engineering by examining the Jet Propulsion Laboratory's (JPL) Mars Pathfinder and Mars Global Surveyor missions to Mars. It contains numerous animations and narrations in addition to detailed graphics and text. Six interactive laboratories are included to help understand topics such as the…

The CanMars Analogue Mission: Lessons Learned for Mars Sample Return

Science.gov (United States)

Osinski, G. R.; Beaty, D.; Battler, M.; Caudill, C.; Francis, R.; Haltigin, T.; Hipkin, V.; Pilles, E.

2018-04-01

We present an overview and lessons learned for Mars Sample Return from CanMars — an analogue mission that simulated a Mars 2020-like cache mission. Data from 39 sols of operations conducted in the Utah desert in 2015 and 2016 are presented.

Tidal locking of habitable exoplanets

Science.gov (United States)

Barnes, Rory

2017-12-01

Potentially habitable planets can orbit close enough to their host star that the differential gravity across their diameters can produce an elongated shape. Frictional forces inside the planet prevent the bulges from aligning perfectly with the host star and result in torques that alter the planet's rotational angular momentum. Eventually the tidal torques fix the rotation rate at a specific frequency, a process called tidal locking. Tidally locked planets on circular orbits will rotate synchronously, but those on eccentric orbits will either librate or rotate super-synchronously. Although these features of tidal theory are well known, a systematic survey of the rotational evolution of potentially habitable exoplanets using classic equilibrium tide theories has not been undertaken. I calculate how habitable planets evolve under two commonly used models and find, for example, that one model predicts that the Earth's rotation rate would have synchronized after 4.5 Gyr if its initial rotation period was 3 days, it had no satellites, and it always maintained the modern Earth's tidal properties. Lower mass stellar hosts will induce stronger tidal effects on potentially habitable planets, and tidal locking is possible for most planets in the habitable zones of GKM dwarf stars. For fast-rotating planets, both models predict eccentricity growth and that circularization can only occur once the rotational frequency is similar to the orbital frequency. The orbits of potentially habitable planets of very late M dwarfs ([InlineEquation not available: see fulltext.]) are very likely to be circularized within 1 Gyr, and hence, those planets will be synchronous rotators. Proxima b is almost assuredly tidally locked, but its orbit may not have circularized yet, so the planet could be rotating super-synchronously today. The evolution of the isolated and potentially habitable Kepler planet candidates is computed and about half could be tidally locked. Finally, projected TESS planets

Effects of psychosocial stress on the goal-directed and habit memory systems during learning and later execution.

Science.gov (United States)

Fournier, Marion; d'Arripe-Longueville, Fabienne; Radel, Rémi

2017-03-01

Instrumental learning occurs through both goal-directed and habit memory systems, which are supported by anatomically distinct brain systems. Interestingly, stress may promote habits at the expense of goal-directed performance, since stress before training in an instrumental task was found to cause individuals to carry on with the learned association in spite of a devalued outcome. These findings nevertheless left pending questions, and it has been difficult to determine which system is primarily affected by stress (an improved habit system, an impaired goal-directed system, or both) and at what point the stress acts (at the moment of learning by making more resistant habits, or after devaluation by making individuals less sensitive to change in the outcome value). The present study (N=72 participants, 63 males and 9 females) aimed to answer these questions with (i) an instrumental task that dissociates the two memory systems and (ii) three conditions of psychosocial stress exposure (Trier Social Stress Test): stress induced before learning, before devaluation, and not induced for the control group. The study confirms that exposure to psychosocial stress leads to habitual performance. Moreover, it provides new insight into this effect by locating its origin as an impairment in the capacity of the goal-directed system rather than a reinforcement in habit learning. These results are discussed in light of recent neurobiological models of stress and memory. Copyright © 2016 Elsevier Ltd. All rights reserved.

Implementing planetary protection measures on the Mars Science Laboratory.

Science.gov (United States)

Benardini, James N; La Duc, Myron T; Beaudet, Robert A; Koukol, Robert

2014-01-01

The Mars Science Laboratory (MSL), comprising a cruise stage; an aeroshell; an entry, descent, and landing system; and the radioisotope thermoelectric generator-powered Curiosity rover, made history with its unprecedented sky crane landing on Mars on August 6, 2012. The mission's primary science objective has been to explore the area surrounding Gale Crater and assess its habitability for past life. Because microbial contamination could profoundly impact the integrity of the mission and compliance with international treaty was required, planetary protection measures were implemented on MSL hardware to verify that bioburden levels complied with NASA regulations. By applying the proper antimicrobial countermeasures throughout all phases of assembly, the total bacterial endospore burden of MSL at the time of launch was kept to 2.78×10⁵ spores, well within the required specification of less than 5.0×10⁵ spores. The total spore burden of the exposed surfaces of the landed MSL hardware was 5.64×10⁴, well below the allowed limit of 3.0×10⁵ spores. At the time of launch, the MSL spacecraft was burdened with an average of 22 spores/m², which included both planned landed and planned impacted hardware. Here, we report the results of a campaign to implement and verify planetary protection measures on the MSL flight system.

URGENSI STRATEGI DISPOSITION HABITS OF MIND MATEMATIS

Directory of Open Access Journals (Sweden)

Bety Miliyawati

2014-09-01

Full Text Available ABSTRAK Kebiasaan berpikir (habits of mind memiliki peranan penting dalam proses pembelajaran dan perkembangan individu dalam membantu memecahkan masalah. Habits Of Mind (HOM adalah kebiasaan berpikir secara fleksibel, mengelola secara empulsif, mendengarkan dengan empati, membiasakan mengajukan pertanyaan, kebiasaan menyelesaikan masalah secara efektif, membiasakan menggunakan pengetahuan masa lalu untuk situasi baru, membiasakan berkomunikasi, berpikir jernih dengan tepat, menggunakan semua indera ketika mengumpulkan informasi, mencoba cara berbeda dan menghasilkan ide-ide yang baru, kebiasaan untuk merespon, kebiasaan untuk mengambil resiko, biasa bertanggung jawab, memiliki rasa humor, membiasakan berpikir interaktif dengan orang lain, bersikap terbuka dan mencoba terus-menerus. Hal ini sejalan dengan tujuan Kurikulum 2013, yaitu mempersiapkan generasi bangsa agar memiliki kemampuan hidup sebagai pribadi dan warga negara yang produktif, kreatif, inovatif, dan afektif. Artikel ini dikaji didasarkan atas analisis terhadap: (1 karakteristik matematika, (2 habits of mind matematis, dan (3 disposition contoh strategi HOM dalam pembelajaran matematika yang dikembangkan pada siswa. Kata Kunci    : Pembelajaran, Karakteristik Matematika, Habits of Mind Matematis   ABSTRACT Habits of mind have an important role in the learning process and the development of individuals in helping to solve the problem. Habits Of Mind (HOM is the habit of thinking flexibly, manage empulsif, listening with empathy, get used to ask questions, solve problems effectively habit, the habit of using past knowledge to new situations, to get used to communicate, think clearly, precisely, using all the senses when gathering information, trying different ways and generate new ideas, habits to respond, the habit to take risks, the usual charge, have a sense of humor, familiarize interactive thinking with others, be open and try constantly. This is in line with the curriculum

Mars and Men

Science.gov (United States)

Muehlberger, W.

2001-01-01

Wherever mankind travels in space, people will always be preceded by unmanned probes that will provide the first bit of information. But there comes a time when we've learned all we can by unmanned vehicles. Man comes on the scene and makes the decisions about what is most valuable to us here, and that makes space into a new laboratory. Photography plays a vital role in all that John Glenn, in 'The View from Space'. Why do you take a photograph? We took a lot of documentation pictures because we were supposed to. But a lot of photographs were taken on instinct things you can't predict you're going to see or that are going to impress you. You say, 'Now I've got to take a picture of that" or "Look at the way that is positioned' or' Look at the way the sun is shining on that." Those 'stand-back' pictures were taken with aesthetics in mind, to capture and document the venture itself." Eugene Cernan in 'The View from Space'. The Apollo mode for a Science Support Room in Mission Control will not work for Mars. The time delay makes it nearly useless. Our team was available for instantaneous reaction and assistance to the crew on EVA. Therefore the Science Support Team has to be on Mars! The crew that went out the day before will do the supporting. They will hand off to each other for the next EVA. They will send a daily report back to Earth as to what was accomplished, problems that need resolution, supporting video, data, etc. etc. In Apollo, that was the role of my "Tiger Team," who sat in Gene Krantz' office watching and listening but having no role for directly helping the Back Room. They wrote a summary of the EVA, what was accomplished, what got omitted that was important to insert into the next EVA. It was distributed throughout Mission Control- especially to the Big Brass, Flight Director, and the CapCom.

A decision-making process model of young online shoppers.

Science.gov (United States)

Lin, Chin-Feng; Wang, Hui-Fang

2008-12-01

Based on the concepts of brand equity, means-end chain, and Web site trust, this study proposes a novel model called the consumption decision-making process of adolescents (CDMPA) to understand adolescents' Internet consumption habits and behavioral intention toward particular sporting goods. The findings of the CDMPA model can help marketers understand adolescents' consumption preferences and habits for developing effective Internet marketing strategies.

History of Mars

International Nuclear Information System (INIS)

Lewis, J.S.

1988-01-01

The origin and early history of Mars and the relationship between Mars and the other planets are reviewed. The solar system formation and planetary differentiation are examined using data from planetary missions. Different views of Mars are presented, showing how ideas about the planet have changed as the amount of available observational data has increased. Viking aerography and surface characterization are discussed, including the nature of specific atmospheric components and the implications of surface phenomena. Models for the planetary formation and accretion processes are considered. The value of future missions to Mars is stressed

Sustained Manned Mars Presence Enabled by E-sail Technology and Asteroid Water Mining

Science.gov (United States)

Janhunen, Pekka; Merikallio, Sini; Toivanen, Petri; Envall, M. Jouni

The Electric Solar Wind Sail (E-sail) can produce 0.5-1 N of inexhaustible and controllable propellantless thrust [1]. The E-sail is based on electrostatic Coulomb interaction between charged thin tethers and solar wind ions. It was invented in 2006, was developed to TRL 4-5 in 2011-2013 with ESAIL FP7 project (http://www.electric-sailing.fi/fp7) and a CubeSat small-scale flight test is in course (ESTCube-1). The E-sail provides a flexible and efficient way of moving 0-2 tonne sized cargo payloads in the solar system without consuming propellant. Given the E-sail, one could use it to make manned exploration of the solar system more affordable by combining it with asteroid water mining. One first sends a miner spacecraft to an asteroid or asteroids, either by E-sail or traditional means. Many asteroids are known to contain water and liberating it only requires heating the material one piece at a time in a leak tight container. About 2 tonne miner can produce 50 tonnes of water per year which is sufficient to sustain continuous manned traffic between Earth and Mars. If the ice-bearing asteroid resides roughly at Mars distance, it takes 3 years for a 0.7 N E-sailer to transport a 10 tonne water/ice payload to Mars orbit or Earth C3 orbit. Thus one needs a fleet of 15 E-sail transport spacecraft plus replacements to ferry 50 tonnes of water yearly to Earth C3 (1/3) and Mars orbit (2/3). The mass of one transporter is 300 kg [2]. One needs to launch max 1.5 tonne mass of new E-sail transporters per year and in practice much less since it is simple to reuse them. This infrastructure is enough to supply 17 tonnes of water yearly at Earth C3 and 33 tonnes in Mars orbit. Orbital water can be used by manned exploration in three ways: (1) for potable water and for making oxygen, (2) for radiation shielding, (3) for LH2/LOX propellant. Up to 75 % of the wet mass of the manned module could be water (50 % propellant and 25 % radiation shield water). On top of this the total mass

An overview of NASA ISS human engineering and habitability: past, present, and future.

Science.gov (United States)

Fitts, D; Architecture, B

2000-09-01

The International Space Station (ISS) is the first major NASA project to provide human engineering an equal system engineering an equal system engineering status to other disciplines. The incorporation and verification of hundreds of human engineering requirements applied across-the-board to the ISS has provided for a notably more habitable environment to support long duration spaceflight missions than might otherwise have been the case. As the ISS begins to be inhabited and become operational, much work remains in monitoring the effectiveness of the Station's built environment in supporting the range of activities required of a long-duration vehicle. With international partner participation, NASA's ISS Operational Habitability Assessment intends to carry human engineering and habitability considerations into the next phase of the ISS Program with constant attention to opportunities for cost-effective improvements that need to be and can be made to the on-orbit facility. Too, during its operations the ISS must be effectively used as an on-orbit laboratory to promote and expand human engineering/habitability awareness and knowledge to support the international space faring community with the data needed to develop future space vehicles for long-duration missions. As future space mission duration increases, the rise in importance of habitation issues make it imperative that lessons are captured from the experience of human engineering's incorporation into the ISS Program and applied to future NASA programmatic processes.

Vehicle Net Habitable Volume (NHV) and Habitability Assessment

Data.gov (United States)

National Aeronautics and Space Administration — The purpose of this study is to assess habitability on the International Space Station (ISS) in order to better prepare for long-duration spaceflight missions of the...

Measuring Sulfur Isotope Ratios from Solid Samples with the Sample Analysis at Mars Instrument and the Effects of Dead Time Corrections

Science.gov (United States)

Franz, H. B.; Mahaffy, P. R.; Kasprzak, W.; Lyness, E.; Raaen, E.

2011-01-01

The Sample Analysis at Mars (SAM) instrument suite comprises the largest science payload on the Mars Science Laboratory (MSL) "Curiosity" rover. SAM will perform chemical and isotopic analysis of volatile compounds from atmospheric and solid samples to address questions pertaining to habitability and geochemical processes on Mars. Sulfur is a key element of interest in this regard, as sulfur compounds have been detected on the Martian surface by both in situ and remote sensing techniques. Their chemical and isotopic composition can belp constrain environmental conditions and mechanisms at the time of formation. A previous study examined the capability of the SAM quadrupole mass spectrometer (QMS) to determine sulfur isotope ratios of SO2 gas from a statistical perspective. Here we discuss the development of a method for determining sulfur isotope ratios with the QMS by sampling SO2 generated from heating of solid sulfate samples in SAM's pyrolysis oven. This analysis, which was performed with the SAM breadboard system, also required development of a novel treatment of the QMS dead time to accommodate the characteristics of an aging detector.

The subsurface geology of Río Tinto: material examined during a simulated Mars drilling mission for the Mars Astrobiology Research and Technology Experiment (MARTE).

Science.gov (United States)

Prieto-Ballesteros, Olga; Martínez-Frías, Jesús; Schutt, John; Sutter, Brad; Heldmann, Jennifer L; Bell, Mary Sue; Battler, Melissa; Cannon, Howard; Gómez-Elvira, Javier; Stoker, Carol R

2008-10-01

The 2005 Mars Astrobiology Research and Technology Experiment (MARTE) project conducted a simulated 1-month Mars drilling mission in the Río Tinto district, Spain. Dry robotic drilling, core sampling, and biological and geological analytical technologies were collectively tested for the first time for potential use on Mars. Drilling and subsurface sampling and analytical technologies are being explored for Mars because the subsurface is the most likely place to find life on Mars. The objectives of this work are to describe drilling, sampling, and analytical procedures; present the geological analysis of core and borehole material; and examine lessons learned from the drilling simulation. Drilling occurred at an undisclosed location, causing the science team to rely only on mission data for geological and biological interpretations. Core and borehole imaging was used for micromorphological analysis of rock, targeting rock for biological analysis, and making decisions regarding the next day's drilling operations. Drilling reached 606 cm depth into poorly consolidated gossan that allowed only 35% of core recovery and contributed to borehole wall failure during drilling. Core material containing any indication of biology was sampled and analyzed in more detail for its confirmation. Despite the poorly consolidated nature of the subsurface gossan, dry drilling was able to retrieve useful core material for geological and biological analysis. Lessons learned from this drilling simulation can guide the development of dry drilling and subsurface geological and biological analytical technologies for future Mars drilling missions.

Transportation-Driven Mars Surface Operations Supporting an Evolvable Mars Campaign

Science.gov (United States)

Toups, Larry; Brown, Kendall; Hoffman, Stephen J.

2015-01-01

This paper describes the results of a study evaluating options for supporting a series of human missions to a single Mars surface destination. In this scenario the infrastructure emplaced during previous visits to this site is leveraged in following missions. The goal of this single site approach to Mars surface infrastructure is to enable "Steady State" operations by at least 4 crew for up to 500 sols at this site. These characteristics, along with the transportation system used to deliver crew and equipment to and from Mars, are collectively known as the Evolvable Mars Campaign (EMC). Information in this paper is presented in the sequence in which it was accomplished. First, a logical buildup sequence of surface infrastructure was developed to achieve the desired "Steady State" operations on the Mars surface. This was based on a concept of operations that met objectives of the EMC. Second, infrastructure capabilities were identified to carry out this concept of operations. Third, systems (in the form of conceptual elements) were identified to provide these capabilities. This included top-level mass, power and volume estimates for these elements. Fourth, the results were then used in analyses to evaluate three options (18t, 27t, and 40t landed mass) of Mars Lander delivery capability to the surface. Finally, Mars arrival mass estimates were generated based upon the entry, descent, and landing requirements for inclusion in separate assessments of in-space transportation capabilities for the EMC.

Semi-automated operation of Mars Climate Simulation chamber - MCSC modelled for biological experiments

Science.gov (United States)

Tarasashvili, M. V.; Sabashvili, Sh. A.; Tsereteli, S. L.; Aleksidze, N. D.; Dalakishvili, O.

2017-10-01

The Mars Climate Simulation Chamber (MCSC) (GEO PAT 12 522/01) is designed for the investigation of the possible past and present habitability of Mars, as well as for the solution of practical tasks necessary for the colonization and Terraformation of the Planet. There are specific tasks such as the experimental investigation of the biological parameters that allow many terrestrial organisms to adapt to the imitated Martian conditions: chemistry of the ground, atmosphere, temperature, radiation, etc. MCSC is set for the simulation of the conduction of various biological experiments, as well as the selection of extremophile microorganisms for the possible Settlement, Ecopoesis and/or Terraformation purposes and investigation of their physiological functions. For long-term purposes, it is possible to cultivate genetically modified organisms (e.g., plants) adapted to the Martian conditions for future Martian agriculture to sustain human Mars missions and permanent settlements. The size of the chamber allows preliminary testing of the functionality of space-station mini-models and personal protection devices such as space-suits, covering and building materials and other structures. The reliability of the experimental biotechnological materials can also be tested over a period of years. Complex and thorough research has been performed to acquire the most appropriate technical tools for the accurate engineering of the MCSC and precious programmed simulation of Martian environmental conditions. This paper describes the construction and technical details of the equipment of the MCSC, which allows its semi-automated, long-term operation.

Investigating the Early Atmospheres of Earth and Mars through Rivers, Raindrops, and Lava Flows

Science.gov (United States)

Som, Sanjoy M.

2010-11-01

The discovery of a habitable Earth-like planet beyond our solar-system will be remembered as one of the major breakthroughs of 21st century science, and of the same magnitude as Copernicus' heliocentric model dating from the mid 16th century. The real astrobiological breakthrough will be the added results from atmospheric remote sensing of such planets to determine habitability. Atmospheres, in both concentration and composition are suggestive of processes occurring at the planetary surface and upper crust. Unfortunately, only the modern Earth's atmosphere is known to be habitable. I investigate the density and pressure of our planet's early atmosphere before the rise of oxygen 2.5 billion years ago, because our planet was very much alive microbially. Such knowledge gives us another example of a habitable atmosphere. I also investigates the atmosphere of early Mars, as geomorphic signatures on its surface are suggestive of a past where liquid water may have present in a warmer climate, conditions suitable for the emergence of life, compared with today's 6 mbar CO2-dominated atmosphere. Using tools of fluvial geomorphology, I find that the largest river-valleys on Mars do not record a signature of a sustained hydrological cycle, in which precipitation onto a drainage basin induces many cycles of water flow, substrate incision, water ponding, and return to the atmosphere via evaporation. Rather, I conclude that while episodes of flow did occur in perhaps warmer environments, those periods were short-lived and overprinted onto a dominantly cold and dry planet. For Earth, I develop a new method of investigating atmospheric density and pressure using the size of raindrop imprints, and find that raindrop imprints preserved in the 2.7 billion year old Ventersdorp Supergroup of South Africa are consistent with precipitation falling in an atmosphere of near-surface density 0.1 kg/m3, compared to a modern value of 1.2 kg/m3, further suggesting a nitrogen level of at most

HABEBEE: habitability of eyeball-exo-Earths.

Science.gov (United States)

Angerhausen, Daniel; Sapers, Haley; Citron, Robert; Bergantini, Alexandre; Lutz, Stefanie; Queiroz, Luciano Lopes; da Rosa Alexandre, Marcelo; Araujo, Ana Carolina Vieira

2013-03-01

Extrasolar Earth and super-Earth planets orbiting within the habitable zone of M dwarf host stars may play a significant role in the discovery of habitable environments beyond Earth. Spectroscopic characterization of these exoplanets with respect to habitability requires the determination of habitability parameters with respect to remote sensing. The habitable zone of dwarf stars is located in close proximity to the host star, such that exoplanets orbiting within this zone will likely be tidally locked. On terrestrial planets with an icy shell, this may produce a liquid water ocean at the substellar point, one particular "Eyeball Earth" state. In this research proposal, HABEBEE: exploring the HABitability of Eyeball-Exo-Earths, we define the parameters necessary to achieve a stable icy Eyeball Earth capable of supporting life. Astronomical and geochemical research will define parameters needed to simulate potentially habitable environments on an icy Eyeball Earth planet. Biological requirements will be based on detailed studies of microbial communities within Earth analog environments. Using the interdisciplinary results of both the physical and biological teams, we will set up a simulation chamber to expose a cold- and UV-tolerant microbial community to the theoretically derived Eyeball Earth climate states, simulating the composition, atmosphere, physical parameters, and stellar irradiation. Combining the results of both studies will enable us to derive observable parameters as well as target decision guidance and feasibility analysis for upcoming astronomical platforms.

Waves in the middle and upper atmosphere of Mars as seen by the Radio Science Experiment MaRS on Mars Express

Science.gov (United States)

Tellmann, S.; Paetzold, M.; Häusler, B.; Hinson, D. P.; Peter, K.; Tyler, G. L.

2017-12-01

Atmospheric waves play a crucial role in the Martian atmosphere. They are responsible for the redistribution of momentum, energy and dust and for the coupling of the different atmospheric regions on Mars. Almost all kinds of waves have been observed in the lower atmosphere (e.g. stationary and transient waves, baroclinic waves as well as migrating and non-migrating thermal tides, gravity waves, etc...). Atmospheric waves are also known to exist in the middle atmosphere of Mars ( 70-120 km, e.g. by the SPICAM instrument on Mars Express). In the thermosphere, thermal tides have been observed e.g. by radio occultation or accelerometer measurements on MGS. Recently, the NGIMS instrument on MAVEN reported gravity waves in the thermosphere of Mars. Radio Science profiles from the Mars Express Radio Science experiment MaRS on Mars Express can analyse the temperature, pressure and neutral number density profiles in the lower atmosphere (from a few hundred metres above the surface up to 40-50 km) and electron density profiles in the ionosphere of Mars. Wavelike structures have been detected below the main ionospheric layers (M1 & M2) and in the topside of the ionosphere. The two coherent frequencies of the MaRS experiment allow to discriminate between plasma density fluctuations in the ionosphere and Doppler related frequency shifts caused by spacecraft movement. A careful analysis of the observed electron density fluctuations in combination with sensitivity studies of the radio occultation technique will be used to classify the observed fluctuations. The MaRS experiment is funded by DLR under grant 50QM1401.

Drastic Environmental Change on Mars: Applying the Lessons Learned on Earth

Science.gov (United States)

Fairen, A.; Schulze-Makuch, D.; Irwin, L. N.

2014-12-01

Rapid and drastic environmental change has occurred frequently on Earth, posing a critical challenge to life. However, directional selection has overcome those challenges and driven life on our planet to ever increasing diversity and complexity. Based on our knowledge of the natural history of Earth, the effect of drastic environmental changes on a planet's biosphere can be attributed to three main factors: (1) the nature and time scale of change, (2) the composition of the biosphere prior to change, and (3) the nature of the environment following the change. Mars has undergone even larger environmental changes than Earth, from habitable conditions under which the origin of life (or transfer of life from Earth) seem plausible, to a dry and cold planet punctuated by wetter conditions. Given its planetary history, life on Mars could have retreated to a psychrophilic lifestyle in the deep subsurface or to environmental near-surface niches, such as hydrothermal regions and caves. Further, strong directional selection could have pushed putative martian life to evolve alternating cycles between active and dormant forms, as well as the innovation of new traits adapted to challenging near-surface conditions (e.g., use of H2O2 or perchlorates as antifreeze compounds).

Sample Analysis at Mars (SAM) and Mars Organic Molecule Analyzer (MOMA) as Critical In Situ Investigation for Targeting Mars Returned Samples

Science.gov (United States)

Freissinet, C.; Glavin, D. P.; Mahaffy, P. R.; Szopa, C.; Buch, A.; Goesmann, F.; Goetz, W.; Raulin, F.; SAM Science Team; MOMA Science Team

2018-04-01

SAM (Curiosity) and MOMA (ExoMars) Mars instruments, seeking for organics and biosignatures, are essential to establish taphonomic windows of preservation of molecules, in order to target the most interesting samples to return from Mars.

Biological life-support systems for Mars mission.

Science.gov (United States)

Gitelson, J I

1992-01-01

Mars mission like the Lunar base is the first venture to maintain human life beyond earth biosphere. So far, all manned space missions including the longest ones used stocked reserves and can not be considered egress from biosphere. Conventional path proposed by technology for Martian mission LSS is to use physical-chemical approaches proved by the experience of astronautics. But the problem of man living beyond the limits of the earth biosphere can be fundamentally solved by making a closed ecosystem for him. The choice optimum for a Mars mission LSS can be substantiated by comparing the merits and demerits of physical-chemical and biological principles without ruling out possible compromise between them. The work gives comparative analysis of ecological and physical-chemical principles for LSS. Taking into consideration universal significance of ecological problems with artificial LSS as a particular case of their solution, complexity and high cost of large-scale experiments with manned LSS, it would be expedient for these works to have the status of an International Program open to be joined. A program of making artificial biospheres based on preceding experience and analysis of current situation is proposed.

An ordinary camera in an extraordinary location: Outreach with the Mars Webcam

Science.gov (United States)

Ormston, T.; Denis, M.; Scuka, D.; Griebel, H.

2011-09-01

The European Space Agency's Mars Express mission was launched in 2003 and was Europe's first mission to Mars. On-board was a small camera designed to provide ‘visual telemetry’ of the separation of the Beagle-2 lander. After achieving its goal it was shut down while the primary science mission of Mars Express got underway. In 2007 this camera was reactivated by the flight control team of Mars Express for the purpose of providing public education and outreach—turning it into the ‘Mars Webcam’.The camera is a small, 640×480 pixel colour CMOS camera with a wide-angle 30°×40° field of view. This makes it very similar in almost every way to the average home PC webcam. The major difference is that this webcam is not in an average location but is instead in orbit around Mars. On a strict basis of non-interference with the primary science activities, the camera is turned on to provide unique wide-angle views of the planet below.A highly automated process ensures that the observations are scheduled on the spacecraft and then uploaded to the internet as rapidly as possible. There is no intermediate stage, so that visitors to the Mars Webcam blog serve as ‘citizen scientists’. Full raw datasets and processing instructions are provided along with a mechanism to allow visitors to comment on the blog. Members of the public are encouraged to use this in either a personal or an educational context and work with the images. We then take their excellent work and showcase it back on the blog. We even apply techniques developed by them to improve the data and webcam experience for others.The accessibility and simplicity of the images also makes the data ideal for educational use, especially as educational projects can then be showcased on the site as inspiration for others. The oft-neglected target audience of space enthusiasts is also important as this allows them to participate as part of an interplanetary instrument team.This paper will cover the history of the

Testing a Mars science outpost in the Antarctic dry valleys

Science.gov (United States)

Andersen, D. T.; Mckay, C. P.; Wharton, R. A.; Rummel, J. D.

1992-01-01

Field research conducted in the Antarctic has been providing insights about the nature of Mars in the science disciplines of exobiology and geology. Located in the McMurdo Dry Valleys of southern Victoria Land (160 deg and 164 deg E longitude and 76 deg 30 min and 78 deg 30 min S latitude), research outposts are inhabited by teams of 4-6 scientists. It is proposed that the design of these outposts be expanded to enable meaningful tests of many of the systems that will be needed for the successful conduct of exploration activities on Mars. Although there are some important differences between the environment in the Antarctic dry valleys and on Mars, the many similarities and particularly the field science activities, make the dry valleys a useful terrestrial analog to conditions on Mars. Three areas have been identified for testing at a small science outpost in the dry valleys: (1) studying human factors and physiology in an isolated environment; (2) testing emerging technologies (e.g. innovative power management systems, advanced life support facilities including partial bioregenerative life support systems for water recycling and food growth, telerobotics, etc.); and (3) conducting basic scientific research that will enhance understanding of Mars while contributing to the planning for human exploration. It is suggested that an important early result of a Mars habitat program will be the experience gained by interfacing humans and their supporting technology in a remote and stressful environment.

Evaluation of meteorites as habitats for terrestrial microorganisms: Results from the Nullarbor Plain, Australia, a Mars analogue site

Science.gov (United States)

Tait, Alastair W.; Wilson, Siobhan A.; Tomkins, Andrew G.; Gagen, Emma J.; Fallon, Stewart J.; Southam, Gordon

2017-10-01

Unambiguous identification of biosignatures on Mars requires access to well-characterized, long-lasting geochemical standards at the planet's surface that can be modified by theoretical martian life. Ordinary chondrites, which are ancient meteorites that commonly fall to the surface of Mars and Earth, have well-characterized, narrow ranges in trace element and isotope geochemistry compared to martian rocks. Given that their mineralogy is more attractive to known chemolithotrophic life than the basaltic rocks that dominate the martian surface, exogenic rocks (e.g., chondritic meteorites) may be good places to look for signs of prior life endemic to Mars. In this study, we show that ordinary chondrites, collected from the arid Australian Nullarbor Plain, are commonly colonized and inhabited by terrestrial microorganisms that are endemic to this Mars analogue site. These terrestrial endolithic and chasmolithic microbial contaminants are commonly found in close association with hygroscopic veins of gypsum and Mg-calcite, which have formed within cracks penetrating deep into the meteorites. Terrestrial bacteria are observed within corrosion cavities, where troilite (FeS) oxidation has produced jarosite [KFe3(SO4)2(OH)6]. Where terrestrial microorganisms have colonized primary silicate minerals and secondary calcite, these mineral surfaces are heavily etched. Our results show that inhabitation of meteorites by terrestrial microorganisms in arid environments relies upon humidity and pH regulation by minerals. Furthermore, microbial colonization affects the weathering of meteorites and production of sulfate, carbonate, Fe-oxide and smectite minerals that can preserve chemical and isotopic biosignatures for thousands to millions of years on Earth. Meteorites are thus habitable by terrestrial microorganisms, even under highly desiccating environmental conditions of relevance to Mars. They may therefore be useful as chemical and isotopic ;standards; that preserve evidence of

Using the International Space Station (ISS) Oxygen Generation Assembly (OGA) Is Not Feasible for Mars Transit

Science.gov (United States)

Jones, Harry W.

2016-01-01

A review of two papers on improving the International Space Station (ISS) Oxygen Generation Assembly (OGA) shows that it would not save substantial mass on a Mars transit. The ISS OGA requires redesign for satisfactory operation, even for the ISS. The planned improvements of the OGA for ISS would not be sufficient to make it suitable for Mars, because Mars transit life support has significantly different requirements than ISS. The OGA for Mars should have lower mass, better reliability and maintainability, greater safety, radiation hardening, and capability for quiescent operation. NASA's methodical, disciplined systems engineering process should be used to develop the appropriate system.

Characterizing Exoplanet Habitability with Emission Spectroscopy

Science.gov (United States)

Robinson, Tyler

2018-01-01

Results from NASA’s Kepler mission and other recent exoplanet surveys have demonstrated that potentially habitable exoplanets are relatively common, especially in the case of low-mass stellar hosts. The next key question that must be addressed for such planets is whether or not these worlds are actually habitable, implying they could sustain surface liquid water. Only through investigations of the potential habitability of exoplanets and through searches for biosignatures from these planets will we be able to understand if the emergence of life is a common phenomenon in our galaxy. Emission spectroscopy for transiting exoplanets (sometimes called secondary eclipse spectroscopy) is a powerful technique that future missions will use to study the atmospheres and surfaces of worlds orbiting in the habitable zones of nearby, low-mass stars. Emission observations that span the mid-infrared wavelength range for potentially habitable exoplanets provide opportunities to detect key habitability and life signatures, and also allow observers to probe atmospheric and surface temperatures. This presentation will outline the case for using emission spectroscopy to understand if an exoplanet can sustain surface liquid water, which is believed to be a critical precursor to the origin of life.

Aerial Deployment and Inflation System for Mars Helium Balloons

Science.gov (United States)

Lachenmeler, Tim; Fairbrother, Debora; Shreves, Chris; Hall, Jeffery, L.; Kerzhanovich, Viktor V.; Pauken, Michael T.; Walsh, Gerald J.; White, Christopher V.

2009-01-01

A method is examined for safely deploying and inflating helium balloons for missions at Mars. The key for making it possible to deploy balloons that are light enough to be buoyant in the thin, Martian atmosphere is to mitigate the transient forces on the balloon that might tear it. A fully inflated Mars balloon has a diameter of 10 m, so it must be folded up for the trip to Mars, unfolded upon arrival, and then inflated with helium gas in the atmosphere. Safe entry into the Martian atmosphere requires the use of an aeroshell vehicle, which protects against severe heating and pressure loads associated with the hypersonic entry flight. Drag decelerates the aeroshell to supersonic speeds, then two parachutes deploy to slow the vehicle down to the needed safe speed of 25 to 35 m/s for balloon deployment. The parachute system descent dynamic pressure must be approximately 5 Pa or lower at an altitude of 4 km or more above the surface.

Smartphone Habits and Behaviors in Supporting Students Self-Efficacy

Directory of Open Access Journals (Sweden)

Abdur Razzaq

2018-02-01

Full Text Available The widespread of smartphones usage have increased the convenience of accessing information and knowledge sharing for higher learning students. University’s students are exposed with the multi channels of knowledge from various sources primarily from online learning’s resources. The study examines smartphone habit, internet literacy, and mobile learning in relation to self-efficacy. Self-efficacy refers to the internal forces of a student’s belief in the abilities in utilizing smartphone as educational aid in the context of mobile learning. This study deploys a quantitative approach in assessing the relationship between self-efficacy, internet literacy and smartphone’s habits for of university students. Understanding student self-efficacy is important factor to deliver an effective ways in supporting mobile learning activities. In addition to documenting the findings of self-efficacy and mobile learning, the research also represents a model of internal and external factors that affects student self-efficacy to make mobile learning successful.

McMurdo Dry Valleys, Antarctica - A Mars Phoenix Mission Analog

Science.gov (United States)

Tamppari, L. K.; Anderson, R. M.; Archer, D.; Douglas, S.; Kounaves, S. P.; McKay, C. P.; Ming, Douglas W.; Moore, Q.; Quinn, J. E.; Smith, P. H.;

Quick trips to Mars

International Nuclear Information System (INIS)

Hornung, R.

1991-01-01

The design of a Mars Mission Vehicle that would have to be launched by two very heavy lift launch vehicles is described along with plans for a mission to Mars. The vehicle has three nuclear engine for rocket vehicle application (NERVA) boosters with a fourth in the center that acts as a dual mode system. The fourth generates electrical power while in route, but it also helps lift the vehicle out of earth orbit. A Mars Ascent Vehicle (MAV), a Mars transfer vehicle stage, and a Mars Excursion Vehicle (MEV) are located on the front end of this vehicle. Other aspects of this research including aerobraking, heat shielding, nuclear thermal rocket engines, a mars mission summary, closed Brayton cycle with and without regeneration, liquid hydrogen propellant storage, etc. are addressed

Can't control yourself? Monitor those bad habits.

Science.gov (United States)

Quinn, Jeffrey M; Pascoe, Anthony; Wood, Wendy; Neal, David T

2010-04-01

What strategies can people use to control unwanted habits? Past work has focused on controlling other kinds of automatic impulses, especially temptations. The nature of habit cuing calls for certain self-control strategies. Because the slow-to-change memory trace of habits is not amenable to change or reinterpretation, successful habit control involves inhibiting the unwanted response when activated in memory. In support, two episode-sampling diary studies demonstrated that bad habits, unlike responses to temptations, were controlled most effectively through spontaneous use of vigilant monitoring (thinking "don't do it," watching carefully for slipups). No other strategy was useful in controlling strong habits, despite that stimulus control was effective at inhibiting responses to temptations. A subsequent experiment showed that vigilant monitoring aids habit control, not by changing the strength of the habit memory trace but by heightening inhibitory, cognitive control processes. The implications of these findings for behavior change interventions are discussed.

Mars Orbiter Camera Views the 'Face on Mars' - Comparison with Viking

Science.gov (United States)

1998-01-01

Shortly after midnight Sunday morning (5 April 1998 12:39 AM PST), the Mars Orbiter Camera (MOC) on the Mars Global Surveyor (MGS) spacecraft successfully acquired a high resolution image of the 'Face on Mars' feature in the Cydonia region. The image was transmitted to Earth on Sunday, and retrieved from the mission computer data base Monday morning (6 April 1998). The image was processed at the Malin Space Science Systems (MSSS) facility 9:15 AM and the raw image immediately transferred to the Jet Propulsion Laboratory (JPL) for release to the Internet. The images shown here were subsequently processed at MSSS.The picture was acquired 375 seconds after the spacecraft's 220th close approach to Mars. At that time, the 'Face', located at approximately 40.8o N, 9.6o W, was 275 miles (444 km) from the spacecraft. The 'morning' sun was 25o above the horizon. The picture has a resolution of 14.1 feet (4.3 meters) per pixel, making it ten times higher resolution than the best previous image of the feature, which was taken by the Viking Mission in the mid-1970's. The full image covers an area 2.7 miles (4.4 km) wide and 25.7 miles (41.5 km) long.In this comparison, the best Viking image has been enlarged to 3.3 times its original resolution, and the MOC image has been decreased by a similar 3.3 times, creating images of roughly the same size. In addition, the MOC images have been geometrically transformed to a more overhead projection (different from the mercator map projection of PIA01440 & 1441) for ease of comparison with the Viking image. The left image is a portion of Viking Orbiter 1 frame 070A13, the middle image is a portion of MOC frame shown normally, and the right image is the same MOC frame but with the brightness inverted to simulate the approximate lighting conditions of the Viking image.Processing Image processing has been applied to the images in order to improve the visibility of features. This processing included the following steps: The image was

[Medical students' smoking habits and attitudes about cessation].

Science.gov (United States)

Rinfel, József; Oberling, János; Tóth, Ildikó; Prugberger, László; Nagy, Lajos

2011-03-20

Medical years are very important in shaping the attitudes of future doctors. It is proven that doctors who smoke do not advise their patient to stop smoking. We have to know the students' smoking habits and attitudes about smoking cessation to make them interested in the fight against tobacco. To investigate medical students' smoking habits and attitudes about cessation. We applied the Hungarian translation of the Global Health Professionals Student Survey. Medical students from the first and fifth year filled in the survey anonymously during the seminars. Statistical analysis was performed with SPSS. In both years 245 students filled in the questionnaire. In the first year 30.8%, in the fifth year 38.9% of the students were defined as smokers. During the academic study the number of daily smokers and the number of smoked cigarettes increases. Students require training about smoking cessation, however they would entrust it to a specialist. Based on our data we need a teaching block in the curricula about smoking and smoking cessation.

Mars Stratigraphy Mission

Science.gov (United States)

Budney, C. J.; Miller, S. L.; Cutts, J. A.

2000-01-01

The Mars Stratigraphy Mission lands a rover on the surface of Mars which descends down a cliff in Valles Marineris to study the stratigraphy. The rover carries a unique complement of instruments to analyze and age-date materials encountered during descent past 2 km of strata. The science objective for the Mars Stratigraphy Mission is to identify the geologic history of the layered deposits in the Valles Marineris region of Mars. This includes constraining the time interval for formation of these deposits by measuring the ages of various layers and determining the origin of the deposits (volcanic or sedimentary) by measuring their composition and imaging their morphology.

Nuclear power station main control room habitability

International Nuclear Information System (INIS)

Paschal, W.B.; Knous, W.S.

1989-01-01

The main control room at a nuclear power station must remain habitable during a variety of plant conditions and postulated events. The control room habitability requirement and the function of the heating, ventilating, air-conditioning, and air treatment system are to control environmental factors, such as temperature, pressure, humidity, radiation, and toxic gas. Habitability requirements provide for the safety of personnel and enable operation of equipment required to function in the main control room. Habitability as an issue has been gaining prominence with the Advisor Committee of Reactor Safeguards and the Nuclear Regulatory Commission since the incident at Three Mile Island. Their concern is the ability of the presently installed habitability systems to control the main control room environment after an accident. This paper discusses main control room HVAC systems; the concern, requirements, and results of NRC surveys and notices; and an approach to control room habitability reviews

Tectonic evolution of Mars

International Nuclear Information System (INIS)

Wise, D.U.; Golombek, M.P.; McGill, G.E.

1979-01-01

Any model for the tectonic evolution of Mars must account for two major crustal elements: the Tharsis bulge and the topographically low and lightly crated northern third of the planet. Ages determined by crater density indicate that both of these elements came into existence very early in Martian history, a conclusion that holds no matter which of the current crater density versus age curves is used. The size of these two major crustal elements and their sequential development suggest that both may be related to a global-scale internal process. It is proposed that the resurfacing of the northern third of Mars is related to subcrustal erosion and isostatic foundering during the life of a first-order convection cell. With the demise of the cell, denser segregations of metallic materials began to coalesce as a gravitatively unstable layer which finally overturned to form the core. In the overturn, lighter crustal materials was shifted laterally and underplated beneath Tharsis to cause rapid and permanent isostatic rise. This was followed by a long-lived thermal phase produced by the hot underplate and by the gravitative energy of core formation slowly making its way to the surface to produce the Tharsis volcanics

Mars at Opposition

Science.gov (United States)

Riddle, Bob

2010-01-01

On January 29, Mars will reach opposition, a point along its orbit around the Sun where Mars will be directly opposite from the Sun in a two-planet and Sun line-up with the Earth in between. At this opposition, the Earth and Mars will be separated by nearly 100 million km. An opposition is similar to a full Moon in that the planet at opposition…

Redox stratification of an ancient lake in Gale crater, Mars.

Science.gov (United States)

Hurowitz, J A; Grotzinger, J P; Fischer, W W; McLennan, S M; Milliken, R E; Stein, N; Vasavada, A R; Blake, D F; Dehouck, E; Eigenbrode, J L; Fairén, A G; Frydenvang, J; Gellert, R; Grant, J A; Gupta, S; Herkenhoff, K E; Ming, D W; Rampe, E B; Schmidt, M E; Siebach, K L; Stack-Morgan, K; Sumner, D Y; Wiens, R C

2017-06-02

In 2012, NASA's Curiosity rover landed on Mars to assess its potential as a habitat for past life and investigate the paleoclimate record preserved by sedimentary rocks inside the ~150-kilometer-diameter Gale impact crater. Geological reconstructions from Curiosity rover data have revealed an ancient, habitable lake environment fed by rivers draining into the crater. We synthesize geochemical and mineralogical data from lake-bed mudstones collected during the first 1300 martian solar days of rover operations in Gale. We present evidence for lake redox stratification, established by depth-dependent variations in atmospheric oxidant and dissolved-solute concentrations. Paleoclimate proxy data indicate that a transition from colder to warmer climate conditions is preserved in the stratigraphy. Finally, a late phase of geochemical modification by saline fluids is recognized. Copyright © 2017, American Association for the Advancement of Science.

An Outrageous Geological Hypothesis for the Early Mars Hydro-climatic Conundrum

Science.gov (United States)

Baker, V. R.

2016-12-01

Nearly a century ago a Science paper by W. M. Davis described the role for an "outrageous geological hypothesis" (OGH) as encouraging, "…a contemplation deliberate enough to seek out what conditions would make the outrage seem permissible and reasonable." Davis even advocated in 1926 that Earth scientists seriously consider "the Wegener outrage of wandering continents"- the OGH that ultimately led to the most important unifying concept for understanding the nature of Earthlike planets. Does this concept of a mobile lithosphere, manifesting itself on Earth as plate tectonics, have relevance for understanding the nature of early Mars? Conceptual arguments have been presented claiming that Mars could never have had an early phase of lithospheric dynamics similar to that associated with Earth's plate tectonics. Nevertheless, a total rejection of this OGH precludes any possibility of considering (1) the conditions that might make such dynamics possible, and (2) connections among the many phenomena that can be collectively accounted for by the OGH. While all scientific arguments are intrinsically fallible, nature presents us with absolute realities. For Mars the latter consist of the numerous anomalies related to planetary evolution that either can be explained piecemeal by ad hoc hypotheses, or, alternatively, might be viewed as part of something to be explained by a unifying, working hypothesis that may seem outrageous in the light of current theory. Briefly stated, the Early Mars OGH envisions a pre-Late Heavy Bombardment (> 4 Ga) phase of lithospheric subduction that helped generate the very powerful core dynamo while also emplacing near the core-mantle boundary a reservoir of volatiles that subsequently influenced the later Mars history of punctuated evolution, involving episodic volcanism and transient states of a denser atmosphere with associated, active hydrological cycling, including the temporary surficial expressions of oceans, lakes, glaciers, and rivers.

Functional neuroimaging of avoidance habits in OCD

Science.gov (United States)

Gillan, Claire M; Apergis-Schoute, Annemieke M; Morein-Zamir, Sharon; Urcelay, Gonzalo P; Sule, Akeem; Fineberg, Naomi A; Sahakian, Barbara J; Robbins, Trevor W

2016-01-01

Objective The goal of this study was to determine the neural correlates of excessive habit formation in obsessive-compulsive disorder (OCD). We aimed to (i) test for neurobiological convergence with the known pathophysiology of OCD and (ii) infer, based on abnormalities in brain activation, whether these habits arise from dysfunction in the goal-directed or habit system. Method Thirty-seven OCD patients and 33 controls learned to avoid shocks while undergoing a functional Magnetic Resonance Imaging (fMRI) scan. Following 4 blocks of training, we tested if the avoidance response had become a habit by removing the threat of shock and measuring continued avoidance. We tested for task-related differences in brain activity in 3 ROIs, the caudate, putamen and medial orbitofrontal cortex at a statistical threshold of phabit formation in OCD patients, which was associated with hyper-activation in the caudate. Activation in this region was also associated with subjective ratings of increased urge to perform habits. The OCD group, as a whole, showed hyper-activation in the medial orbitofrontal cortex (mOFC) during the acquisition of avoidance, however this did not relate directly to habit formation. Conclusions OCD patients exhibited excessive habits that were associated with hyper-activation in a key region implicated in the pathophysiology of OCD, the caudate nucleus. Prior studies suggest that this region is important for goal-directed behavior, suggesting that habit-forming biases in OCD may be a result of impairments in this system, rather than differences in the build up of stimulus-response habits themselves. PMID:25526600

24 CFR 203.673 - Habitability.

Science.gov (United States)

2010-04-01

... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Habitability. 203.673 Section 203.673 Housing and Urban Development Regulations Relating to Housing and Urban Development (Continued... FAMILY MORTGAGE INSURANCE Servicing Responsibilities Occupied Conveyance § 203.673 Habitability. (a) For...

Measurement of Mars Analog Soil Dielectric Properties for Mars 2020 Radar Science Applications

Science.gov (United States)

Decrossas, E.; Bell, D. J.; Jin, C.; Steinfeld, D.; Batres, J.

2017-12-01

On multiple solar system missions, radar instruments have been used to probe subsurface geomorphology and to infer chemical composition based on the dielectric signature derived from the reflected signal. One important planetary application is the identification of subsurface water ice at Mars. Low frequency, 15 MHz to 25 MHz, instruments like SHARAD have been used from Mars orbit to investigate subsurface features from 10's to 1000's of meters below the surface of Mars with a vertical resolution of 15m and a horizontal resolution of 300 to 3000 meters. SHARAD has been able to identify vast layers of CO2 and water ice. The ground-penetrating RIMFAX instrument that will ride on the back of the Mars 2020 rover will operate over the 150 MHz to 1200 MHz band and penetrate to a depth of 10 meters with a vertical resolution of 15 to 30 cm. RIMFAX will be able to identify near surface water ice if it exists below the travel path of the Mars 2020 rover. Identification of near surface water ice has science application to current and past Mars hydrologic processes and to the potential for finding remnants of past Mars biologic activity. Identification of near surface water ice also has application to future human missions that would benefit from access to a Mars local water source. Recently, JPL investigators have been pursuing a secondary use of telecom signals to capture bistatic radar signatures from subsurface areas surrounding the rover but away from its travel path. A particularly promising potential source would be the telecom signal from a proposed Mars Helicopter back to the Mars 2020 rover. The Mars 2020 rover will be equipped with up to three telecom subsystems. The Rover Relay telecom subsystem operates at UHF receiving at 435 MHz frequency. Anticipating opportunistic collection of near-surface bistatic radar signatures from telecom signals received at the rover, it is valuable to understand the dielectric properties of the Martian soil in each of these three

Habits and Virtues: Does it Matter if a Leader Kicks a Dog?

Directory of Open Access Journals (Sweden)

Joanne Ciulla

2014-12-01

Full Text Available This paper argues that it is reasonable to make attributions about a leader’s character based on minor incidents such as kicking a dog. It begins with a short review of the relevant literature from leadership studies and social psychology on how our prototypes of leaders affect the attributions we make about them. Then the paper examines the role of virtues, habits, and dispositional statements to show why an act such as kicking a dog can offer insight into a leader’s moral character.

Models of formation and activity of spring mounds in the mechertate-chrita-sidi el hani system, eastern Tunisia: implications for the habitability of Mars.

Science.gov (United States)

Essefi, Elhoucine; Komatsu, Goro; Fairén, Alberto G; Chan, Marjorie A; Yaich, Chokri

2014-08-28

Spring mounds on Earth and on Mars could represent optimal niches of life development. If life ever occurred on Mars, ancient spring deposits would be excellent localities to search for morphological or chemical remnants of an ancient biosphere. In this work, we investigate models of formation and activity of well-exposed spring mounds in the Mechertate-Chrita-Sidi El Hani (MCSH) system, eastern Tunisia. We then use these models to explore possible spring mound formation on Mars. In the MCSH system, the genesis of the spring mounds is a direct consequence of groundwater upwelling, triggered by tectonics and/or hydraulics. As they are oriented preferentially along faults, they can be considered as fault spring mounds, implying a tectonic influence in their formation process. However, the hydraulic pressure generated by the convergence of aquifers towards the surface of the system also allows consideration of an origin as artesian spring mounds. In the case of the MCSH system, our geologic data presented here show that both models are valid, and we propose a combined hydro-tectonic model as the likely formation mechanism of artesian-fault spring mounds. During their evolution from the embryonic (early) to the islet ("island") stages, spring mounds are also shaped by eolian accumulations and induration processes. Similarly, spring mounds have been suggested to be relatively common in certain provinces on the Martian surface, but their mode of formation is still a matter of debate. We propose that the tectonic, hydraulic, and combined hydro-tectonic models describing the spring mounds at MCSH could be relevant as Martian analogs because: (i) the Martian subsurface may be over pressured, potentially expelling mineral-enriched waters as spring mounds on the surface; (ii) the Martian subsurface may be fractured, causing alignment of the spring mounds in preferential orientations; and (iii) indurated eolian sedimentation and erosional remnants are common features on Mars

Models of Formation and Activity of Spring Mounds in the Mechertate-Chrita-Sidi El Hani System, Eastern Tunisia: Implications for the Habitability of Mars

Directory of Open Access Journals (Sweden)

Elhoucine Essefi

2014-08-01

Full Text Available Spring mounds on Earth and on Mars could represent optimal niches of life development. If life ever occurred on Mars, ancient spring deposits would be excellent localities to search for morphological or chemical remnants of an ancient biosphere. In this work, we investigate models of formation and activity of well-exposed spring mounds in the Mechertate-Chrita-Sidi El Hani (MCSH system, eastern Tunisia. We then use these models to explore possible spring mound formation on Mars. In the MCSH system, the genesis of the spring mounds is a direct consequence of groundwater upwelling, triggered by tectonics and/or hydraulics. As they are oriented preferentially along faults, they can be considered as fault spring mounds, implying a tectonic influence in their formation process. However, the hydraulic pressure generated by the convergence of aquifers towards the surface of the system also allows consideration of an origin as artesian spring mounds. In the case of the MCSH system, our geologic data presented here show that both models are valid, and we propose a combined hydro-tectonic model as the likely formation mechanism of artesian-fault spring mounds. During their evolution from the embryonic (early to the islet (“island” stages, spring mounds are also shaped by eolian accumulations and induration processes. Similarly, spring mounds have been suggested to be relatively common in certain provinces on the Martian surface, but their mode of formation is still a matter of debate. We propose that the tectonic, hydraulic, and combined hydro-tectonic models describing the spring mounds at MCSH could be relevant as Martian analogs because: (i the Martian subsurface may be over pressured, potentially expelling mineral-enriched waters as spring mounds on the surface; (ii the Martian subsurface may be fractured, causing alignment of the spring mounds in preferential orientations; and (iii indurated eolian sedimentation and erosional remnants are common

Guidelines for 2008 MARS exercise

CERN Multimedia

HR Department

2008-01-01

Full details of the Merit Appraisal and Recognition Scheme (MARS) are available via the HR Department’s homepage or directly on the Department’s MARS web page: https://cern.ch/hr-dept/ https://cern.ch/hr-eguide/mars/mars.asp You will find on these pages: MARS procedures including the MARS timetable for proposals and decisions; Regulations with links to the scheme’s statutory basis; Frequently Asked Questions; Useful documents with links to relevant documentation; e.g. mandate of the Senior Staff Advisory Committee (SSAC); Related links and contacts. HR Department Tel. 73566

Evaluation of control room habitability in case of LOCA for Maanshan NPP using codes RADTRAD, HABIT and ALOHA

International Nuclear Information System (INIS)

Hsu, Wen-Sheng; Wang, Jong-Rong; Chen, Hsiung-Chih; Chiang, Yu; Chen, Shao-Wen; Shih, Chunkuan

2018-01-01

The method for the evaluation of the control room habitability is presented in this paper with focus on Maanshan PWR nuclear power plant (NPP) using the codes RADTRAD, HABIT, and ALOHA. Therefore, this paper is divided into two parts: The first part is the evaluation of the cumulative dose at the control room, the exclusion area boundary (EAB) and the low population zone (LPZ) in case of an design basis loss of coolant accident (DBA/LOCA). For this first part, the Maanshan NPP models of the code RADTRAD/SNAP were used for the analysis. The second part is the evaluation of the control room habitability under the assumption of CO 2 storage burst. For this part, the HABIT and ALOHA codes were used. As result it was seen that the RADTRAD calculation results are below the failure criteria of standard review plan (SRP) and 10 CFR 100.11. The HABIT and ALOHA results are below the R.G. 1.78 failure criteria. These results indicate that Maanshan NPP' habitability can be maintained under the above conditions.

The GEM-Mars general circulation model for Mars: Description and evaluation

Science.gov (United States)

Neary, L.; Daerden, F.

2018-01-01

GEM-Mars is a gridpoint-based three-dimensional general circulation model (GCM) of the Mars atmosphere extending from the surface to approximately 150 km based on the GEM (Global Environmental Multiscale) model, part of the operational weather forecasting and data assimilation system for Canada. After the initial modification for Mars, the model has undergone considerable changes. GEM-Mars is now based on GEM 4.2.0 and many physical parameterizations have been added for Mars-specific atmospheric processes and surface-atmosphere exchange. The model simulates interactive carbon dioxide-, dust-, water- and atmospheric chemistry cycles. Dust and water ice clouds are radiatively active. Size distributed dust is lifted by saltation and dust devils. The model includes 16 chemical species (CO2, Argon, N2, O2, CO, H2O, CH4, O3, O(1D), O, H, H2, OH, HO2, H2O2 and O2(a1Δg)) and has fully interactive photochemistry (15 reactions) and gas-phase chemistry (31 reactions). GEM-Mars provides a good simulation of the water and ozone cycles. A variety of other passive tracers can be included for dedicated studies, such as the emission of methane. The model has both a hydrostatic and non-hydrostatic formulation, and together with a flexible grid definition provides a single platform for simulations on a variety of horizontal scales. The model code is fully parallelized using OMP and MPI. Model results are evaluated by comparison to a selection of observations from instruments on the surface and in orbit, relating to atmosphere and surface temperature and pressure, dust and ice content, polar ice mass, polar argon, and global water and ozone vertical columns. GEM-Mars will play an integral part in the analysis and interpretation of data that is received by the NOMAD spectrometer on the ESA-Roskosmos ExoMars Trace Gas Orbiter. The present paper provides an overview of the current status and capabilities of the GEM-Mars model and lays the foundations for more in-depth studies in support

Breaking car use habits

DEFF Research Database (Denmark)

Thøgersen, John; Møller, Berit Thorup

2008-01-01

Based on calls for innovative ways of reducing car traffic and research indicating that car driving is often the result of habitual decision-making and choice processes, this paper reports on a field experiment designed to test a tool aimed to entice drivers to skip the habitual choice of the car...... and consider using-or at least trying-public transport instead. About 1,000 car drivers participated in the experiment either as experimental subjects, receiving a free one-month travelcard, or as control subjects. As predicted, the intervention had a significant impact on drivers' use of public transport...... and it also neutralized the impact of car driving habits on mode choice. However, in the longer run (i.e., four months after the experiment) experimental subjects did not use public transport more than control subjects. Hence, it seems that although many car drivers choose travel mode habitually, their final...

Report of the Workshop for Life Detection in Samples from Mars

Science.gov (United States)

Kminek, Gerhard; Conley, Catherine; Allen, Carlton C.; Bartlett, Douglas H.; Beaty, David W.; Benning, Liane G.; Bhartia, Rohit; Boston, Penelope J.; Duchaine, Caroline; Farmer, Jack D.;

'Mars-shine'

Science.gov (United States)

2005-01-01

[figure removed for brevity, see original site] 'Mars-shine' Composite NASA's Mars Exploration Rover Spirit continues to take advantage of favorable solar power conditions to conduct occasional nighttime astronomical observations from the summit region of 'Husband Hill.' Spirit has been observing the martian moons Phobos and Deimos to learn more about their orbits and surface properties. This has included observing eclipses. On Earth, a solar eclipse occurs when the Moon's orbit takes it exactly between the Sun and Earth, casting parts of Earth into shadow. A lunar eclipse occurs when the Earth is exactly between the Sun and the Moon, casting the Moon into shadow and often giving it a ghostly orange-reddish color. This color is created by sunlight reflected through Earth's atmosphere into the shadowed region. The primary difference between terrestrial and martian eclipses is that Mars' moons are too small to completely block the Sun from view during solar eclipses. Recently, Spirit observed a 'lunar' eclipse on Mars. Phobos, the larger of the two martian moons, was photographed while slipping into the shadow of Mars. Jim Bell, the astronomer in charge of the rover's panoramic camera (Pancam), suggested calling it a 'Phobal' eclipse rather than a lunar eclipse as a way of identifying which of the dozens of moons in our solar system was being cast into shadow. With the help of the Jet Propulsion Laboratory's navigation team, the Pancam team planned instructions to Spirit for acquiring the views shown here of Phobos as it entered into a lunar eclipse on the evening of the rover's 639th martian day, or sol (Oct. 20, 2005) on Mars. This image is a time-lapse composite of eight Pancam images of Phobos moving across the martian sky. The entire eclipse lasted more than 26 minutes, but Spirit was able to observe only in the first 15 minutes. During the time closest to the shadow crossing, Spirit's cameras were programmed to take images every 10 seconds. In the first three

Mars Trek: An Interactive Web Portal for Current and Future Missions to Mars

Science.gov (United States)

Law, E.; Day, B.

2017-09-01

NASA's Mars Trek (https://marstrek.jpl.nasa.gov) provides a web-based Portal and a suite of interactive visualization and analysis tools to enable mission planners, lunar scientists, and engineers to access mapped data products from past and current missions to Mars. During the past year, the capabilities and data served by Mars Trek have been significantly expanded beyond its original design as a public outreach tool. At the request of NASA's Science Mission Directorate and Human Exploration Operations Mission Directorate, Mars Trek's technology and capabilities are now being extended to support site selection and analysis activities for the first human missions to Mars.

Mars Trek: An Interactive Web Portal for Current and Future Missions to Mars

Science.gov (United States)

Law, E.; Day, B.

2017-01-01

NASA's Mars Trek (https://marstrek.jpl.nasa.gov) provides a web-based Portal and a suite of interactive visualization and analysis tools to enable mission planners, lunar scientists, and engineers to access mapped data products from past and current missions to Mars. During the past year, the capabilities and data served by Mars Trek have been significantly expanded beyond its original design as a public outreach tool. At the request of NASA's Science Mission Directorate and Human Exploration Operations Mission Directorate, Mars Trek's technology and capabilities are now being extended to support site selection and analysis activities for the first human missions to Mars.

Iterative metal artefact reduction (MAR) in postsurgical chest CT: comparison of three iMAR-algorithms.

Science.gov (United States)

Aissa, Joel; Boos, Johannes; Sawicki, Lino Morris; Heinzler, Niklas; Krzymyk, Karl; Sedlmair, Martin; Kröpil, Patric; Antoch, Gerald; Thomas, Christoph

2017-11-01

The purpose of this study was to evaluate the impact of three novel iterative metal artefact (iMAR) algorithms on image quality and artefact degree in chest CT of patients with a variety of thoracic metallic implants. 27 postsurgical patients with thoracic implants who underwent clinical chest CT between March and May 2015 in clinical routine were retrospectively included. Images were retrospectively reconstructed with standard weighted filtered back projection (WFBP) and with three iMAR algorithms (iMAR-Algo1 = Cardiac algorithm, iMAR-Algo2 = Pacemaker algorithm and iMAR-Algo3 = ThoracicCoils algorithm). The subjective and objective image quality was assessed. Averaged over all artefacts, artefact degree was significantly lower for the iMAR-Algo1 (58.9 ± 48.5 HU), iMAR-Algo2 (52.7 ± 46.8 HU) and the iMAR-Algo3 (51.9 ± 46.1 HU) compared with WFBP (91.6 ± 81.6 HU, p algorithms, respectively. iMAR-Algo2 and iMAR-Algo3 reconstructions decreased mild and moderate artefacts compared with WFBP and iMAR-Algo1 (p algorithms led to a significant reduction of metal artefacts and increase in overall image quality compared with WFBP in chest CT of patients with metallic implants in subjective and objective analysis. The iMARAlgo2 and iMARAlgo3 were best for mild artefacts. IMARAlgo1 was superior for severe artefacts. Advances in knowledge: Iterative MAR led to significant artefact reduction and increase image-quality compared with WFBP in CT after implementation of thoracic devices. Adjusting iMAR-algorithms to patients' metallic implants can help to improve image quality in CT.

ChemCam activities and discoveries during the nominal mission of the Mars Science Laboratory in Gale crater, Mars

Science.gov (United States)

Maurice, Sylvestre; Clegg, Samuel M.; Wiens, Roger C.; Gasnault, O.; Rapin, W.; Forni, O.; Cousin, Agnes; Sautter, V.; Mangold, Nicolas; Le Deit, L.; Nachon, Marion; Anderson, Ryan; Lanza, Nina; Fabre, Cecile; Payre, Valerie; Lasue, Jeremie; Meslin, Pierre-Yves; LeVeille, Richard A.; Barraclough, Bruce; Beck, Pierre; Bender, Steven C.; Berger, Gilles; Bridges, John C.; Bridges, Nathan; Dromert, Gilles; Dyar, M. Darby; Francis, Raymond; Frydenvang, Jens; Gondet, B.; Ehlmann, Bethany L.; Herkenhoff, Kenneth E.; Johnson, Jeffrey R.; Langevin, Yves; Madsen Morten B.,; Melikechi, N.; Lacour, J.-L.; Le Mouelic, Stephane; Lewin, Eric; Newsom, Horton E.; Ollila, Ann M.; Pinet, Patrick; Schroder, S.; Sirven, Jean-Baptiste; Tokar, Robert L.; Toplis, M.J.; d'Uston, Claude; Vaniman, David; Vasavada, Ashwin R.

2016-01-01

At Gale crater, Mars, ChemCam acquired its first laser-induced breakdown spectroscopy (LIBS) target on Sol 13 of the landed portion of the mission (a Sol is a Mars day). Up to Sol 800, more than 188000 LIBS spectra were acquired on more than 5800 points distributed over about 650 individual targets. We present a comprehensive review of ChemCam scientific accomplishments during that period, together with a focus on the lessons learned from the first use of LIBS in space. For data processing, we describe new tools that had to be developed to account for the uniqueness of Mars data. With regard to chemistry, we present a summary of the composition range measured on Mars for major-element oxides (SiO2, TiO2, Al2O3, FeOT, MgO, CaO, Na2O, K2O) based on various multivariate models, with associated precisions. ChemCam also observed H, and the non-metallic elements C, O, P, and S, which are usually difficult to quantify with LIBS. F and Cl are observed through their molecular lines. We discuss the most relevant LIBS lines for detection of minor and trace elements (Li, Rb, Sr, Ba, Cr, Mn, Ni, and Zn). These results were obtained thanks to comprehensive ground reference datasets, which are set to mimic the expected mineralogy and chemistry on Mars. With regard to the first use of LIBS in space, we analyze and quantify, often for the first time, each of the advantages of using stand-off LIBS in space: no sample preparation, analysis within its petrological context, dust removal, sub-millimeter scale investigation, multi-point analysis, the ability to carry out statistical surveys and whole-rock analyses, and rapid data acquisition. We conclude with a discussion of ChemCam performance to survey the geochemistry of Mars, and its valuable support of decisions about selecting where and whether to make observations with more time and resource-intensive tools in the rover's instrument suite. In the end, we present a bird's-eye view of the many scientific results: discovery of felsic

Mars Express — how to be fastest to the Red Planet

Science.gov (United States)

2003-05-01

Mars Express is the first example of ESA’s new style of developing scientific missions: faster, smarter and more cost-effective, but without compromising reliability and quality - there have been no cuts in tests or pre-launch preparations. Mars Express will face demanding technical challenges during its trip to the Red Planet and ESA engineers have worked hard to make sure it meets them. "With Mars Express, Europe is building its own expertise in many fields. This ranges from the development of science experiments and new technologies - new for European industry - to the control of a mission that includes landing on another planet. We have never done this before,” says Rudi Schmidt, Mars Express Project Manager. Quicker, smarter…safe! Mars Express’s design and development phase has taken about four years, compared with about six years for previous similar missions. And its cost, 300 million euros, is much less than other comparable planetary missions. The ‘magic’ lies in the new managerial approach being used. This new approach includes the reuse of existing hardware and instruments. Also, the mission was developed by a smaller ESA team, who gave more responsibility to industry. Mars Express has been built by a consortium of 24 companies from ESA’s 15 Member States and the United States, led by Astrium as prime contractor. However, mission safety was never compromised. “Although we were under heavy pressure towards the end of the project, we did not drop any of the planned tests to save time. I call this a fast design phase, followed by thorough testing activity,” says Schmidt. This new streamlined development method will continue with Venus Express and probably other future missions. Launch Mars Express will be launched on 2 June on board a Soyuz-Fregat rocket from the Baikonur Cosmodrome in Kazakhstan. The mission consists of an orbiter and a lander, called Beagle 2. In its launch configuration, Mars Express is a honeycombed aluminium box that

Tides and the evolution of planetary habitability.

Science.gov (United States)

Barnes, Rory; Raymond, Sean N; Jackson, Brian; Greenberg, Richard

2008-06-01

Tides raised on a planet by the gravity of its host star can reduce the planet's orbital semi-major axis and eccentricity. This effect is only relevant for planets orbiting very close to their host stars. The habitable zones of low-mass stars are also close in, and tides can alter the orbits of planets in these locations. We calculate the tidal evolution of hypothetical terrestrial planets around low-mass stars and show that tides can evolve planets past the inner edge of the habitable zone, sometimes in less than 1 billion years. This migration requires large eccentricities (>0.5) and low-mass stars ( less or similar to 0.35 M(circle)). Such migration may have important implications for the evolution of the atmosphere, internal heating, and the Gaia hypothesis. Similarly, a planet that is detected interior to the habitable zone could have been habitable in the past. We consider the past habitability of the recently discovered, approximately 5 M(circle) planet, Gliese 581 c. We find that it could have been habitable for reasonable choices of orbital and physical properties as recently as 2 Gyr ago. However, when constraints derived from the additional companions are included, most parameter choices that indicate past habitability require the two inner planets of the system to have crossed their mutual 3:1 mean motion resonance. As this crossing would likely have resulted in resonance capture, which is not observed, we conclude that Gl 581 c was probably never habitable.

Anemometers for Mars. [Viking '75 wind measurements

Science.gov (United States)

Henry, R. M.; Greene, G. C.

1974-01-01

An investigation is conducted concerning the problems involved in the conduction of wind measurements on the planet Mars, taking into account the currently known characteristics of the Martian atmosphere. Problems introduced by the presence of the lander are examined. The suitability of several different types of anemometers for making the measurements is discussed, giving attention to rotating anemometers, sonic anemometers, ion tracers, drag force anemometers, pitot tubes, and thermal anemometers.

An evaluation of Skylab habitability hardware

Science.gov (United States)

Stokes, J.

1974-01-01

For effective mission performance, participants in space missions lasting 30-60 days or longer must be provided with hardware to accommodate their personal needs. Such habitability hardware was provided on Skylab. Equipment defined as habitability hardware was that equipment composing the food system, water system, sleep system, waste management system, personal hygiene system, trash management system, and entertainment equipment. Equipment not specifically defined as habitability hardware but which served that function were the Wardroom window, the exercise equipment, and the intercom system, which was occasionally used for private communications. All Skylab habitability hardware generally functioned as intended for the three missions, and most items could be considered as adequate concepts for future flights of similar duration. Specific components were criticized for their shortcomings.

The evolution of habit in Tempskya

Science.gov (United States)