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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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NASA NTRS2005

We Have the Spaceship; But Where's the Start Button: Human Engineering Issues in the Age of Long Duration Space Exploration - Presentation

This viewgraph presentation addresses the following considerations for human factors engineering during long duration human space flight: gravitational adaptation, 2-D to 3-D adaptation, handles, exercise posture, and space ergonomics. The presentation argues that there is an urgent need to advance research is these areas in preparation for future manned missions.

Hamilton, George↗
NASA NTRS2005

We Have the Spaceship; But Where's the Start Button: Human Engineering Issues in the Age of Long Duration Space Exploration

As long duration space exploration and habitation becomes more commonplace, a number of Human Engineering factors (Gravitational Adaptation, 2-D to 3-D Movement Adaptation, Design Form/Function, and Space Ergonomics to name a few) will become more pronounced. More research and development is needed in these areas or the explorers may find themselves in painful or dangerous situations.

Hamilton, George S.↗
NASA NTRS1995

VLBI Phase-Referenced Observations on Southern Hemisphere HIPPARCOS Radio Start

Presented are multiepoch Very Long Baseline Interferometry (VLBI) observations on Southern Hemisphere radio stars phase-referenced to background radio sources. The differential astrometry analysis results in high-precision determinations of proper motions and parallaxes. The astrophysical implications and astrometric consequences of these results are discussed.

Radio Emission Stars VLBI Radio Astronomy Astrophy↗
NASA NTRS2006

A Practical Approach to Starting Fission Surface Power Development

The Prometheus Power and Propulsion Program has been reformulated to address NASA needs relative to lunar and Mars exploration. Emphasis has switched from the Jupiter Icy Moons Orbiter (JIMO) flight system development to more generalized technology development addressing Fission Surface Power (FSP) and Nuclear Thermal Propulsion (NTP). Current NASA budget priorities and the deferred mission need date for nuclear systems prohibit a fully funded reactor Flight Development Program. However, a modestly funded Advanced Technology Program can and should be conducted to reduce the risk and cost of future flight systems. A potential roadmap for FSP technology development leading to possible flight applications could include three elements: 1) Conceptual Design Studies, 2) Advanced Component Technology, and 3) Non-Nuclear System Testing. The Conceptual Design Studies would expand on recent NASA and DOE analyses while increasing the depth of study in areas of greatest uncertainty such as reactor integration and human-rated shielding. The Advanced Component Technology element would address the major technology risks through development and testing of reactor fuels, structural materials, primary loop components, shielding, power conversion, heat rejection, and power management and distribution (PMAD). The Non-Nuclear System Testing would provide a modular, technology testbed to investigate and resolve system integration issues.

Mason, Lee S.↗
NASA NTRS2007

A Start Toward Micronucleus-Based Decompression Models; Altitude Decompression

Do gaseous micronuclei trigger the formation of bubbles in decompression sickness (DCS)? Most previous instructions for DCS prevention have been oriented toward supersaturated gas in tissue. We are developing a mathematical model that is oriented toward the expected behavior of micronuclei. The issue is simplified in altitude decompressions because the aviator or astronaut is exposed only to decompression, whereas in diving there is a compression before the decompression. The model deals with four variables: duration of breathing of 100% oxygen before going to altitude (O2 prebreathing), altitude of the exposure, exposure duration, and rate of ascent. Assumptions: a) there is a population of micronuclei of various sizes having a range of characteristics, b) micronuclei are stable until they grow to a certain critical nucleation radius, c) it takes time for gas to diffuse in or out of micronuclei, and d) all other variables being equal, growth of micronuclei upon decompression is more rapid at high altitude because of the rarified gas in the micronuclei. To estimate parameters, we use a dataset of 4,756 men in altitude chambers exposed to various combinations of the model s variables. The model predicts occurrence of DCS symptoms quite well. It is notable that both the altitude chamber data and the model show little effect of O2 prebreathing until it lasts more than 60 minutes; this is in contrast to a conventional idea that the benefit of prebreathing is directly due to exponential washout of tissue nitrogen. The delay in response to O2 prebreathing can be interpreted as time required for outward diffusion of nitrogen; when the micronuclei become small enough, they are disabled, either by crushing or because they cannot expand to a critical nucleation size when the subject ascends to altitude.

Van Liew, H. D.↗
NASA NTRS2007

RESOLVE - Starting Point for Partnerships in Lunar and Mars Resource Characterization

The mystery and controversy surrounding the possibility of finding water/ice at the lunar poles of the Moon based on the interpretation of neutron spectrometer data from Lunar Prospector and radar data from Clementine raises questions that both Science and the Human Exploration proponents want answered. From the Science perspective, the determination of lunar volatiles and in particular the increased hydrogen concentration detected at the lunar poles was identified as an important objectives for lunar exploration and understanding the history of the Moon, Sun, and the solar system. From the Human Exploration perspective, the potential for large concentrations of accessible water opens up possibilities for utilizing in-situ resources, known as In-Situ Resource Utilization (ISRU), to implement a sustained and affordable human exploration program of the Moon and beyond through production of propellants, fuel cell reagents, and life support consumables for lunar surface operations and mobility, and Earth-Moon transportation. Both the Science and Human Exploration proponents agree that a mission to the lunar poles to obtain ground truth data is the only means to conclusively answer the questions of whether water/ice exists, how much, what form, and where did it come from. In 2005, NASA initiated the Regolith and Environment Science & Oxygen and Lunar Volatiles Extraction (RESOLVE) project, and is currently developing hardware under the NASA Exploration Technology Development Program (ETDP). The purpose of the project was to begin developing technologies and operations that would answer the fundamental science questions, such as What resources are available on the Moon, where are they, what form, and where did they come from? as well as critical engineering questions, such as How will we mine these resources, what chemical extraction processes are the most practical and efficient, and what are the engineering challenges to be faced in this environment? .

Sanders, Gerald B.↗
NASA NTRS1996

Method and apparatus for pressure pulse arcjet starting

The invention disclosed is directed to a method and apparatus for an arcjet starter. The invention discloses a method of moving an arc from the subsonic region of the thruster to the supersonic region by introducing a pressurized propellant into the casuty of the anode.

Sankovic, John M.↗
NASA NTRS2006

C3 System Performance Simulation and User Manual. Getting Started: Guidelines for Users

This document is a User's Manual describing the C3 Simulation capabilities. The subject work was designed to simulate the communications involved in the flight of a Remotely Operated Aircraft (ROA) using the Opnet software. Opnet provides a comprehensive development environment supporting the modeling of communication networks and distributed systems. It has tools for model design, simulation, data collection, and data analysis. Opnet models are hierarchical -- consisting of a project which contains node models which in turn contain process models. Nodes can be fixed, mobile, or satellite. Links between nodes can be physical or wireless. Communications are packet based. The model is very generic in its current form. Attributes such as frequency and bandwidth can easily be modified to better reflect a specific platform. The model is not fully developed at this stage -- there are still more enhancements to be added. Current issues are documented throughout this guide.

Source record↗
NASA NTRS1999

Globus Quick Start Guide. Globus Software Version 1.1

The Globus Project is a community effort, led by Argonne National Laboratory and the University of Southern California's Information Sciences Institute. Globus is developing the basic software infrastructure for computations that integrate geographically distributed computational and information resources.

Source record↗
NASA NTRS2012

Getting a Cohesive Answer from a Common Start: Scalable Multidisciplinary Analysis through Transformation of a Systems Model

One of the challenges of systems engineering is in working multidisciplinary problems in a cohesive manner. When planning analysis of these problems, system engineers must trade between time and cost for analysis quality and quantity. The quality often correlates with greater run time in multidisciplinary models and the quantity is associated with the number of alternatives that can be analyzed. The trade-off is due to the resource intensive process of creating a cohesive multidisciplinary systems model and analysis. Furthermore, reuse or extension of the models used in one stage of a product life cycle for another is a major challenge. Recent developments have enabled a much less resource-intensive and more rigorous approach than hand-written translation scripts between multi-disciplinary models and their analyses. The key is to work from a core systems model defined in a MOF-based language such as SysML and in leveraging the emerging tool ecosystem, such as Query/View/Transformation (QVT), from the OMG community. SysML was designed to model multidisciplinary systems. The QVT standard was designed to transform SysML models into other models, including those leveraged by engineering analyses. The Europa Habitability Mission (EHM) team has begun to exploit these capabilities. In one case, a Matlab/Simulink model is generated on the fly from a system description for power analysis written in SysML. In a more general case, symbolic analysis (supported by Wolfram Mathematica) is coordinated by data objects transformed from the systems model, enabling extremely flexible and powerful design exploration and analytical investigations of expected system performance.

Operational QVT↗
NASA NTRS2013

The Contribution of Thermally-Pulsing Asymptotic Giant Branch and Red Supergiant Starts to the Luminosities of the Magellanic Clouds at 1-24 micrometers

We present the near-through mid-infrared flux contribution of thermally-pulsing asymptotic giant branch (TP-AGB) and massive red supergiant (RSG) stars to the luminosities of the Large and Small Magellanic Clouds (LMC and SMC, respectively). Combined, the peak contribution from these cool evolved stars occurs at approx 3 - 4 micron, where they produce 32% of the SMC light, and 25% of the LMC flux. The TP-AGB star contribution also peaks at approx 3 - 4 micron and amounts to 21% in both galaxies. The contribution from RSG stars peaks at shorter wavelengths, 2.2 micron, where they provide 11% of the SMC flux, and 7% for the LMC. Both TP-AGB and RSG stars are short lived, and thus potentially impose a large stochastic scatter on the near-IR derived mass-to-light (M/L) ratios of galaxies at rest-frame 1 - 4 micron. To minimize their impact on stellar mass estimates, one can use the M/L ratio at shorter wavelengths (e.g., at 0.8 - 1 micron). At longer wavelengths (much > 8 micron), emission from dust in the interstellar medium dominates the flux. In the LMC, which shows strong polycyclic aromatic hydrocarbon (PAH) emission at 8 micron, TP-AGB and RSG contribute less than 4% of the 8 micron flux. However, 19% of the SMC 8 micron flux is from evolved stars, nearly half of which is produced by the rarest, dustiest, carbon-rich TP-AGB stars. Thus, star formation rates of galaxies, based on an 8 micron flux (e.g., observed-frame 24 micron at z = 2), may be biased modestly high, especially for galaxies with little PAH emission.

Melbourne, J.↗
NASA NTRS2013

Observations from Hinode and SDO of a Twisting and Writhing Start to a Solar-filament-eruption Cascade

Active region eruption of 1 June 2011. Ejective eruption. GOES class C4.1 flare. SDO/AIA, various filters (94, 131, 171, 193, 211, 304, 335 Ang.) High time cadence (24 s) and high spatial resolution (0 .6 pixels). SDO/HMI line-of-sight magnetograms. Hinode observed the onset, and the later decay phase. There are two filament eruptions (filament 1 and filament 2). Filament 1 has slow rise with steps, as in several previous cases. GOES "episodes" play role of "microflares" in other events; that is, filament jumps <=> intensity peaks. Episode 1 brightening: Accompanied by filament 1 s initial motions. (Rest of talk.) Filament 1 becomes unstable, and.. Episode 2 brightening: Flare ribbons following filament 1 s fast liftoff. This destabilizes neighboring filament 2, and... Episode 3 brightening: Flare ribbons of whole system following filament 2 s eruption.Something leads to reconnection; not totally clear what. Reconnection -> twisted flux rope in approx.20 min; episode 1 microflare (flare ribbons; TC) and filament jump. Twist -> writhe, via kink instability; filament-trajectory plateau, approx. 20 min. Writhe -> jump and eruption of filament 1, via instability; episode 2 microflare (flare ribbons; TC). (E.g., Williams et al.) First eruption -> second filament eruption (episode 3 flare ribbons; TC). (E.g., Sterling, Moore; Liu et al.; Torok et al.; Schrijver & Title.). Estimate amount of free energy in newly-twisted field (cf. Moore 1988): where we have taken L and r = 50, 3 arcsec. Energy of the total system is likely 1030 ergs or more. So "no" is answer to question. Additional energy comes from remainder of sheared large loop, shear (free energy) of second filament, etc. (Normally assumed situation.) Some history of twist-induced instability in filament eruptions: e.g., Sakurai, Torok & Kliem, Fan & Gibson, Gilbert et al., van Driel-Gesztelyi et al. Criterion : Kink instability for line-tied tube (Hood & Priest): 2.5pi; for Titov & Demoulin loop (Torok et al): approx.3.5pi We observe here: approx.1.5 turns (3.0pi) over ~50. => consistent with kink instability acting. (Cf. Srivastava et al. (2010): Small flare seen in TRACE and Hinode: approx.6.0pi)

Sterling, Alphonse C.↗
NASA NTRS2014

Start of Eta Car's X-ray Minimum

Analysis of Eta Car's X-ray spectrum in the 2-10 keV band using quicklook data from the XRay Telescope on Swift shows that the flux on July 30, 2014 was 4.9 plus or minus 2.0×10(exp-12) ergs s(exp-1)cm(exp-2). This flux is nearly equal to the X-ray minimum flux seen by RXTE in 2009, 2003.5, and 1998, and indicates that Eta Car has reached its X-ray minimum, as expected based on the 2024-day period derived from previous 2-10 keV observations with RXTE.

X-Ray Telescope↗
NASA NTRS2012

Getting a Cohesive Answer from a Common Start: Scalable Multidisciplinary Analysis through Transformation of a System Model

One of the challenges of systems engineering is in working multidisciplinary problems in a cohesive manner. When planning analysis of these problems, system engineers must tradeoff time and cost for analysis quality and quantity. The quality is associated with the fidelity of the multidisciplinary models and the quantity is associated with the design space that can be analyzed. The tradeoff is due to the resource intensive process of creating a cohesive multidisciplinary system model and analysis. Furthermore, reuse or extension of the models used in one stage of a product life cycle for another is a major challenge. Recent developments have enabled a much less resource-intensive and more rigorous approach than handwritten translation scripts or codes of multidisciplinary models and their analyses. The key is to work from a core system model defined in a MOF-based language such as SysML and in leveraging the emerging tool ecosystem, such as Query-View- Transform (QVT), from the OMG community. SysML was designed to model multidisciplinary systems and analyses. The QVT standard was designed to transform SysML models. The Europa Hability Mission (EHM) team has begun to exploit these capabilities. In one case, a Matlab/Simulink model is generated on the fly from a system description for power analysis written in SysML. In a more general case, a symbolic mathematical framework (supported by Wolfram Mathematica) is coordinated by data objects transformed from the system model, enabling extremely flexible and powerful tradespace exploration and analytical investigations of expected system performance.

Cole, Bjorn↗