3,061 research outputs found

    Planning Related to the Curation and Processing of Returned Martian Samples

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    The Astromaterials Acquisition and Curation Office (henceforth referred to herein as NASA Curation Office) at NASA Johnson Space Center (JSC) is responsible for curating all of NASAs extraterrestrial samples. Under the governing document, NASA Policy Directive (NPD) 7100.10E Curation of Extraterrestrial Materials, JSC is charged with the curation of all extraterrestrial material under NASA control, including future NASA missions. The Directive goes on to define Curation as including documentation, preservation, preparation, and distribution of samples for research, education, and public outreach. Here we describe some of the ongoing planning efforts in curation as they pertain to the return of martian samples in a future, as of yet unplanned, mission

    A multidimensional examination of marital conflict and subjective health over 16 years

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    Guided by stress process perspectives, this study conceptualizes marital conflict as a multidimensional stressor to assess how three aspects of conflict—frequency of disagreements, breadth of disagreements, and cumulative disagreements—impact subjective health. Longitudinal data of married couples spanning 16 years (n = 373 couples) were analyzed using multilevel modeling. For husbands, more frequent disagreements than usual within a given year were associated with poorer subjective health. For wives, the greater cumulative effects of disagreements over 16 years were harmful for subjective health. We discuss how gendered self‐representations and relationship power issues help explain the findings. This research demonstrated the importance of examining multiple aspects of marital conflict to reveal that their subjective health consequences function differently for wives and husbands.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/151831/1/pere12292_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/151831/2/pere12292.pd

    Applicability and Utility of the Astromaterials X-Ray Computed Tomography Laboratory at Johnson Space Center

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    The Astromaterials Acquisition and Curation Office at NASAs Johnson Space Center is responsible for curating all of NASAs astromaterial sample collections (i.e. Apollo samples, Luna Samples, Antarctic Meteorites, Cosmic Dust Particles, Microparticle Impact Collection, Genesis solar wind atoms, Stardust comet Wild-2 particles, Stardust interstellar particles, and Hayabusa asteroid Itokawa particles) [1-3]. To assist in sample curation and distribution, JSC Curation has recently installed an X-ray computed tomography (XCT) scanner to visualize and characterize samples in 3D. [3] describes the instrumental set-up and the utility of XCT to astromaterials curation. Here we describe some of the current and future projects and illustrate the usefulness of XCT in studying astromaterials

    The Need for Medical Geology in Space Exploration: Implications for the Journey to Mars and Beyond

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    The previous manned missions to the Moon represent milestones in human ingenuity, perseverance, and intellectual curiosity. They also highlight a major hazard for future human exploration of the Moon and beyond: surface dust. Not only did the dust cause mechanical and structural integrity issues with the suits, the dust "storm" generated upon reentrance into the crew cabin caused "lunar hay fever" and "almost blindness". It was further reported that the allergic response to the dust worsened with each exposure. The lower gravity environment exacerbated the exposure, requiring the astronauts to wear their helmet within the module in order to avoid breathing the irritating particles. Due to the prevalence of these high exposures, the Human Research Roadmap developed by NASA identifies the Risk of Adverse Health and Performance Effects of Celestial Dust Exposure as an area of concern. Extended human exploration will further increase the probability of inadvertent and repeated exposures to celestial dusts. Going forward, hazard assessments of celestial dusts will be determined through sample return efforts prior to astronaut deployment. However, even then the returned samples could also put the Curators, technicians, and scientists at risk during processing and examination

    The Opera Instrument: An Advanced Curation Development for Mars Sample Return Organic Contamination Monitoring

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    Mars Sample Return (MSR) requires strict organic contamination control (CC) and contamination knowledge (CK) as outlined by the Mars 2020 Organic Contamination Panel (OCP). This includes a need to monitor surficial organic contamination to a ng/sq. cm sensitivity level. Archiving and maintaining this degree of surface cleanliness may be difficult but has been achieved. MSR's CK effort will be very important because all returned samples will be studied thoroughly and in minute detail. Consequently, accurate CK must be collected and characterized to best interpret scientific results from the returned samples. The CK data are not only required to make accurate measurements and interpretations for carbon-depleted martian samples, but also to strengthen the validity of science investigations performed on the samples. The Opera instrument prototype is intended to fulfill a CC/CK role in the assembly, cleaning, and overall contamination history of hardware used in the MSR effort, from initial hardware assembly through post-flight sample curation. Opera is intended to monitor particulate and organic contamination using quartz crystal microbalances (QCMs), in a self-contained portable package that is cleanroom-compliant. The Opera prototype is in initial development capable of approximately 100 ng/sq. cm organic contamination sensitivity, with additional development planned to achieve 1 ng/sq. cm. The Opera prototype was funded by the 2017 NASA Johnson Space Center Innovation Charge Account (ICA), which provides funding for small, short-term projects

    Decreased Cognitive/CNS Function in Young Adults at Risk for Hypertension: Effects of Sleep Deprivation

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    Hypertension has been linked to impaired cognitive/CNS function, and some of these changes may precede development of frank essential hypertension. The stress and fatigue of sleep deprivation may exacerbate these cognitive changes in young adults at risk. We hypothesize that individuals at risk for hypertension will show significant declines in cognitive function during a night of sleep deprivation. Fifty-one young adults were recruited for 28-hour total sleep deprivation studies. Hypertension risk was assessed by mildly elevated resting blood pressure and by family history of hypertension. A series of cognitive memory tasks was given at four test sessions across the sleep deprivation period. Although initially comparable in cognitive performance, persons at risk showed larger declines across the night for several indices of working memory, including code substitution, category, and order recall. These results suggest that cognitive/CNS changes may parallel or precede blood pressure dysregulation in the early stages of hypertension development. The role of CNS changes in the etiology of essential hypertension is discussed

    Making Mercury's Core with Light Elements

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    Recent results obtained from the MErcury Surface, Space ENvironment, GEochemistry, and Ranging spacecraft showed the surface of Mercury has low FeO abundances (less than 2 wt%) and high S abundances (approximately 4 wt%), suggesting the oxygen fugacity of Mercury's surface materials is somewhere between 3 to 7 log10 units below the IW buffer. The highly reducing nature of Mercury has resulted in a relatively thin mantle and a large core that has the potential to exhibit an exotic composition in comparison to the other terrestrial planets. This exotic composition may extend to include light elements (e.g., Si, C, S). Furthermore, has argued for a possible primary floatation crust on Mercury composed of graphite, which may require a core that is C-saturated. In order to investigate mercurian core compositions, we conducted piston cylinder experiments at 1 GPa, from 1300 C to 1700 C, using a range of starting compositions consisting of various Si-Fe metal mixtures (Si5Fe95, Si10Fe90, Si22Fe78, and Si35Fe65). All metals were loaded into graphite capsules used to ensure C-saturation during the duration of each experimental run. Our experiments show that Fe-Si metallic alloys exclude carbon relative to more Fe-rich metal. This exclusion of carbon commences within the range of 5 to 10 wt% Si. These results indicate that if Mercury has a Si-rich core (having more than approximately 5 wt% silicon), it would have saturated in carbon at low C abundances allowing for the possible formation of a graphite floatation crust as suggested by. These results have important implications for the thermal and magmatic evolution of Mercury

    Fast ultrasonic phased array inspection of complex geometries delivered through robotic manipulators and high speed data acquisition instrumentation

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    Performance of modern robotic manipulators has enabled research and development of fast automated non-destructive testing (NDT) systems for complex geometries. This paper presents recent outcomes of work aimed at removing the bottleneck due to data acquisition rates, to fully exploit the scanning speed of modern 6-DoF manipulators. State of the art ultrasonic instrumentation has been integrated into a large robot cell to enable fast data acquisition, high scan resolutions and accurate positional encoding. A fibre optic connection between the ultrasonic instrument and the server computer enables data transfer rates up to 1.6GB/s. Multiple data collection methods are compared. Performance of the integrated system allows traditional ultrasonic phased array scanning as well as full matrix capture (FMC). In FMC configuration, linear scan speeds up to 156mm/s with 64 pulses per frame are achieved - this speed is only constrained by the acoustic wave propagation in the component. An 8x increase of the speed (up to 1.25m/s) can be achieved using multiple transmission elements, reaching the physical limits for acceptable acoustic alignment of transmission and reception paths. Scan results, relative to a 1.2m × 3m carbon fibre sample, are presented

    Potential Alteration of Analogue Regolith by X-Ray Computed Tomography

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    The Mars 2020 rover mission will collect and cache samples from the martian surface for possible retrieval and subsequent return to Earth. Mars Returned Samples may provide definitive information about the presence of organic compounds that could shed light on the existence of past or present life on Mars. Post-mission analyses will depend on the development of a set of reliable sample handling and analysis procedures that cover the full range of materials which may or may not contain evidence of past or present martian life [1]

    Meteorite Dust and Health - A Novel Approach for Determining Bulk Compositions for Toxicological Assessments of Precious Materials

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    With the resurgence of human curiosity to explore planetary bodies beyond our own, comes the possibility of health risks associated with the materials covering the surface of these planetary bodies. In order to mitigate these health risks and prepare ourselves for the eventuality of sending humans to other planetary bodies, toxicological evaluations of extraterrestrial materials is imperative (Harrington et al. 2017). Given our close proximity, as well as our increased datasets from various missions (e.g., Apollo, Mars Exploration Rovers, Dawn, etc), the three most likely candidates for initial human surface exploration are the Moon, Mars, and asteroid 4Vesta. Seven samples, including lunar mare basalt NWA 4734, lunar regolith breccia NWA 7611, martian basalt Tissint, martian regolith breccia NWA 7034, a vestian basalt Berthoud, a vestian regolith breccia NWA 2060, and a terrestrial mid-ocean ridge basalt, were examined for bulk chemistry, mineralogy, geochemical reactivity, and inflammatory potential. In this study, we have taken alliquots from these samples, both the fresh samples and those that underwent iron leaching (Tissint, NWA 7034, NWA 4734, MORB), and performed low pressure, high temperature melting experiments to determine the bulk composition of the materials that were previously examined
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