This presentation provides a brief overview of Hydrogen and Fuel Cell technologies for space applications and current NASA activities involving these technologies.
Topics: NASA Technical Reports Server (NTRS), fdea3daf3b5156699f511edf3e9b9ec4
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Topics: NASA Technical Reports Server (NTRS), 0be91b7a68665cf882c2ccee8ad03aff,...
Solar and Heliosphere physics are areas of remarkable data-driven discoveries. Recent advances in high cadence, high-resolution multiwavelength observations, growing amounts of data from realistic modeling, and operational needs for uninterrupted science-quality data coverage generate the demand for a solar metadata standardization and overall healthy data infrastructure. This white paper is prepared as an effort of the working group “Uniform Semantics and Syntax of Solar Observations and...
Topics: NASA Technical Reports Server (NTRS), 27523685ef8456b494cdeacddb56fb4e,...
The high-fidelity and reduced order CFD method's validation and analysis are presented for the Multirotor Test Bed. The reduced-order method uses a rotor-disk model in the OVERFLOW CFD code and is an important aspect of this study. A rotor-trim option loosely coupling the Comprehensive code CAMRAD II with the OVERFLOW CFD code is included in the simulation that captures rotor blade aerodynamics, blade and rotor performance, rotor-rotor, and rotor-body interactions. Detailed comparison and...
Topics: NASA Technical Reports Server (NTRS), 7f9c4cf9cb6f517db6b0fb40eb584c03
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Topics: NASA Technical Reports Server (NTRS), 68603dff261e5d2d9de5a550aa9e6b30
This paper investigates the oversimplification of the inherently complex systems engineering process in space life support. The standard systems engineering process steps are described. The International Space Station (ISS) life support system is explained with its goals and performance criteria. Although it is not usually emphasized, the essential function of developing a hierarchy of systems and subsystems is to simplify the design process. The System Complexity Metric (SCM) shows how this...
Topics: NASA Technical Reports Server (NTRS), 4540cd94d24c4bf29f8773a27faf96b2,...
Previous missions have subjected astronauts to confined space, weightlessness, and increased radiation. These impair astronaut comfort, performance, and future health. The exploration and future settlement of space will depend on the long-term presence of individual humans. This requires the development of space platforms where humans can work and live in health for many years, perhaps generations. A livable space platform must provide adequate volume, gravity, and radiation shielding. This...
Topics: NASA Technical Reports Server (NTRS), 7f9c4cf9cb6f517db6b0fb40eb584c03
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Topics: NASA Technical Reports Server (NTRS), 68603dff261e5d2d9de5a550aa9e6b30
This report describes work performed on Contract NAS3–27720 AoI 13 as part of the NASA Advanced Subsonic Transport (AST) Noise Reduction Technology effort. Computer codes were developed to provide quantitative prediction, design, and analysis capability for several aircraft engine noise sources. The objective was to provide improved, physics-based tools for the exploration of noise-reduction concepts and the understanding of experimental results. Methods and codes focused on fan broadband and...
Topics: NASA Technical Reports Server (NTRS), 0d812b8749475f9994c21c2d80af8c03, General Electric (United...
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Topics: NASA Technical Reports Server (NTRS), 7f9c4cf9cb6f517db6b0fb40eb584c03
The ongoing development of the Global Carbon Project (GCP) global methane (CH4) budget shows a continuation of increasing CH4 emissions and CH4 accumulation in the atmosphere during 2000–2017. Here, we decompose the global budget into 19 regions (18 land and 1 oceanic) and five key source sectors to spatially attribute the observed global trends. A comparison of top-down (TD) (atmospheric and transport model-based) and bottom-up (BU) (inventory- and process model-based) CH4 emission estimates...
Topics: NASA Technical Reports Server (NTRS), 0000-0001-5265-0791, 0000-0001-5554-0897,...
In order to further improve the accuracy of rovibrational IR line lists generated from the “Best Theory +Reliable High-resolution Experiment” (BTRHE) strategy from 0.01-0.05 cm-1, or 300-1500 MHz, to ~10 MHz, we explore the current limits of the Data-Model-Theory synergy by examining the accuracy and consistency of existing data, then propose that “hot” bands in microwave (MW) spectra is the solution we need for future enhancements. The Ames SO2 J=0-20 rovibrational energy levels...
Topics: NASA Technical Reports Server (NTRS), 60dec8a55c6e53cb99acf3519042174c
We review the Best Theory + Reliable High-resolution Experiment (BTRHE) strategy for\nobtaining highly accurate molecular rovibrational line lists with InfraRed (IR) intensities. The\nneed for highly accurate molecular rovibrational line lists is two-fold: a) assignment of the many rovibrational lines for common stable molecules especially those that exhibit a large amplitude motion, such as NH3, or have a high density of states such as SO2; and b) characterization of the atmospheres of...
Topics: NASA Technical Reports Server (NTRS), 60dec8a55c6e53cb99acf3519042174c
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Topics: NASA Technical Reports Server (NTRS), 0000-0002-1949-4720, 11c578a19c8143919337ac9b8fa4f8cb,...
Exploring planetary atmospheres uncovers important information for how our solar system formed and evolved. While remote sensing is extensively used, some crucial observations require in-situ measurements by an atmospheric probe. Given their scientific importance, probe missions to Saturn, Uranus and Neptune are considered for the coming decades. In anticipation of future probe missions, the software tool VIPRE was developed as proof-of-concept to facilitate selection of probe entry locations....
Topics: NASA Technical Reports Server (NTRS), 378807a24b534eb7a79b3b676034744f,...
Conventional, grease-lubricated actuators for space mechanisms can achieve long life but must be heated above about 213 K, or -60 °C, to function in extremely cold environments. This paper first overviews a new NASA project that is developing two rotational actuators that can achieve long life without the need for supplemental heating. Then, the impacts of heating conventional, grease-lubricated actuators are studied for operation in a lunar permanently shadowed region. To facilitate the...
Topics: NASA Technical Reports Server (NTRS), Erica Montbach, fdea3daf3b5156699f511edf3e9b9ec4, Glenn...
The National Aeronautics and Space Administration (NASA) of the United States of America (US) has initiated the Artemis Moon to Mars program to send astronauts (the first woman and person of color) back to the lunar surface, create a sustainable human lunar exploration program, and lead the first human exploration mission to the Mars surface in the 2030’s. A major objective of this program is to characterize the resources that exist on the Moon and Mars, and learn how to utilize them for...
Topics: NASA Technical Reports Server (NTRS), 4c6a2b878d76521da887cdcb2564bf90
We have performed a census of the young stellar populations near the Corona Australis molecular cloud using photometric and kinematic data from several sources, particularly Gaia EDR3, and spectroscopy of hundreds of candidate members. We have compiled a catalog of 393 members of Corona Australis, (39 at >M6), 293 (36) of which are spectroscopically classified for the first time in this work. We find that Corona Australis can be described in terms of two stellar populations, a younger one (a...
Topics: NASA Technical Reports Server (NTRS), 0000-0001-9223-9091, 0000-0003-2822-2951,...
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Topics: NASA Technical Reports Server (NTRS), 68603dff261e5d2d9de5a550aa9e6b30
Aboard the polar-orbiting SNPP satellite, the VIIRS instrument has been in operation since launch in October 2011. It is a visible and infrared radiometer with a unique panchromatic channel capability designated as a day-night band (DNB). This channel covers wavelengths from 0.5 to 0.9 µm and is designed with a near-constant spatial resolution for Earth observations 24 h a day. The DNB operates at 3 gain stages (low, middle, and high) to cover a large dynamic range. An onboard solar diffuser...
Topics: NASA Technical Reports Server (NTRS), efb1c389f6e95ddd810caa5fdc1060ad
Within the national airspace system (NAS), efficient use of spectrum remains a challenge; as UAS and UAM missions evolve, the amount of mission-critical aircraft communications are expected to significantly grow. To accommodate the increased demand, NASA Glenn Research Center is investigating artificial intelligence approaches that could dynamically allocate spectrum; however, these solutions are driven by communication and aviation data items, many of which are not directly available. One such...
Topics: NASA Technical Reports Server (NTRS), ea338826fb9e5728a0945e4693739f84, Hongxiang Li, Nathan...
Our study suggests that the global CO2 fertilization effect (CFE) on vegetation photosynthesis has declined during the past four decades. The Comments suggest that the temporal inconsistency in AVHRR data and the attribution method undermine the results’ robustness. Here, we provide additional evidence that these arguments did not affect our finding and that the global decline in CFE is robust.
Topics: NASA Technical Reports Server (NTRS), 1d717387f04e43ceba9aef276f6e8ff6,...
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Topics: NASA Technical Reports Server (NTRS), Alfred University, c081505712f75b7f97cd5b9c9645624e, Cooper...
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Topics: NASA Technical Reports Server (NTRS), ff293352e05b51ca965411fc94f5e325
We propose a system that uses semantic object detections to localize a microgravity free-flyer. Many applications require absolute localization in a known reference frame, such as the execution of waypoint trajectories defined by human\noperators. Classical geometric methods build a map of point features, which may not be able to be associated after lighting or\nenvironmental changes. By contrast, semantics remain invariant to changes up to the robustness of the detection algorithm\nand motion...
Topics: NASA Technical Reports Server (NTRS), 184389ee78e05dd8ab6050cafbb52187, Ian D Miller, Ryan Soussan,...
The coma of comet C/2016 R2 (PanSTARRS) is one of the most chemically peculiar ever observed, in particular due to its extremely high CO/H2O and N(+2)/H2O ratios, and unusual trace volatile abundances. However, the complex shape of its CO emission lines, as well as uncertainties in the coma structure and excitation, has lead to ambiguities in the total CO production rate. We performed high-resolution, spatially, spectrally, and temporally resolved CO observations using the James Clerk Maxwell...
Topics: NASA Technical Reports Server (NTRS), 0000-0001-5653-3584, 0000-0001-6752-5109,...
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Topics: NASA Technical Reports Server (NTRS), 68603dff261e5d2d9de5a550aa9e6b30
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Topics: NASA Technical Reports Server (NTRS), 199c40960ed646fca72ff45be92fdad6, Abbi Brown, Anne...
Understanding how inner planets acquired their volatiles such as hydrogen (H) is fundamental to constrain models of solar system formation [e.g. 1]. One avenue of estimating the H content and isotopic characteristics of differentiated planets is to analyze the samples we have from them as meteorites. Ideally, the H content and isotopic characteristic of the mantle sources of these igneous rocks should give insight into the volatile origin of each planetary body. The mantle H signatures can be...
Topics: NASA Technical Reports Server (NTRS), 99fa64c96f0950678abfcdd84ba26bf5, Arizona State University,...
Review of Open-source Discrete Element Method Softwares: \n\nThree open-source solutions have been investigated for integration into OceanWATERS: Yade, EsysParticle, and ProjectChrono.
Topics: NASA Technical Reports Server (NTRS), 30956d12b05c56f99ba04cefabd82400
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Topics: NASA Technical Reports Server (NTRS), 30956d12b05c56f99ba04cefabd82400
The need for sustainable agricultural practices to meet the food, feed, and fuel demands of a growing global population while reducing detrimental environmental impacts has driven research in multi-faceted approaches to agricultural sustainability. Perennial cropping systems and microbial biofertilizer supplements are two emerging strategies to increase agricultural sustainability that are studied in tandem for the first time in this study. During the establishment phase of a perennial...
Topics: NASA Technical Reports Server (NTRS), 4a4428b600ec4244ba3bc206e1cafb5d,...
The Common Habitat is a large, long-duration habitat being explored as part of a conceptual study (not an active NASA program) that uses an SLS core stage Liquid Oxygen (LOX) tank as its primary structure. It is intended for use on the Moon as part of a permanently occupied outpost, on Mars as part of an outpost that will be occupied for hundreds of days at a time, and in deep space as part of the Deep Space Exploration Vehicle where it will support crewed missions up to 1200 days in duration....
Topics: NASA Technical Reports Server (NTRS), 0000-0001-8489-861X, 4c6a2b878d76521da887cdcb2564bf90, Brady...
Discoveries in the 1980s greatly expanded speleologists’ understanding of therole that hypogenic groundwater flow can play developingcaves at depth. Ascending groundwater charged with carbon dioxide and,especially,hydrogen sulfide,can readily dissolve carbonate bedrock just below and above the water table. Sulfuric acid speleogenesis, in which anoxic, rising, sulfidic groundwater mixes with oxygenated cave atmosphere to form aggressive sulfuric acid (H2SO4), formed spectacular caves in...
Topics: NASA Technical Reports Server (NTRS), cef137352a405cc388702e0f9c4d637d, Daniels Jones, Donald...
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Topics: NASA Technical Reports Server (NTRS), Annette R Gray, ff293352e05b51ca965411fc94f5e325, Marshall...
AMEGO-X is a Compton/pair gamma-ray telescope, submitted to NASA's 2021 MIDEX AO, which will image and survey the medium-energy gamma-ray sky between 100 keV and 1 GeV. It is designed to detect and characterize gamma-ray emission from multi-messenger sources. On short time scales (
Topics: NASA Technical Reports Server (NTRS), 6cf3f949a7665f4e8446330e18b2253b, Catholic University of...
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Topics: NASA Technical Reports Server (NTRS), e53641f275f15469a1b19a8980e09171
The Moon-to-Mars Planetary Autonomous Construction Technology (MMPACT) project, under NASA’s Game Changing Division (GCD) aims to research, develop, and demonstrate lunar surface construction capabilities[1].A fundamental step in lunar infrastructure development is to quantify the geotechnical properties of lunar regolith, such as shear strength (Mohr-Coulomb cohesion and angle of internal friction), com-pression and bearing properties, and angle of re-pose. Knowledge of these geotechnical...
Topics: NASA Technical Reports Server (NTRS), 644ec0025805570ba93f60b54a6c6f15,...
STEReO brings together several technologies in Unmanned Aircraft Systems (UAS) Traffic Management (UTM), Autonomy, Communications, Human Factors, and Domain Expertise & Tools, aimed at providing scalability and flexibility, as well as operational resiliency to dynamic changes during a disaster event. Some of the concepts STEReO explores are: collaborative tools to ingest remote sensing information and distribute a common mission operating picture, apply ad-hoc communication networks to...
Topics: NASA Technical Reports Server (NTRS), 7f9c4cf9cb6f517db6b0fb40eb584c03
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Topics: NASA Technical Reports Server (NTRS), 68603dff261e5d2d9de5a550aa9e6b30, Alison Park, Langley...
Day 2:\n\nLater Ecosystem Goals (UAM Maturity Levels (UMLs) 3 & 4) Overview\n\nPanel:\n\nLater UMLs & the Future of Autonomy\n\nModerator: Wes Ryan, NASA
Topics: NASA Technical Reports Server (NTRS), e53641f275f15469a1b19a8980e09171
Plume-Surface Interaction (PSI) between lander engine plumes and regolith soil creates hazards in obscuration and contamination by particle clouds, high-energy ejecta streams, and landing area cratering damage. The MSFC Fluid Dynamics Branch is developing simulation tools to offer a predictive PSI capability to NASA customers such as the Human Lander System (HLS) and Commercial Lunar Payload Services (CLPS). The Gas-Granular Flow Solver (GGFS) is the main application tool for coupled...
Topics: NASA Technical Reports Server (NTRS), 99fa64c96f0950678abfcdd84ba26bf5
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Topics: NASA Technical Reports Server (NTRS), 68603dff261e5d2d9de5a550aa9e6b30
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Topics: NASA Technical Reports Server (NTRS), 4c6a2b878d76521da887cdcb2564bf90
This paper discusses the effect of global model error on probability of collision\n(Pc) determination. Modifications to the Pc formulation for cross-correlation of\norbital error in prediction are developed and assessed for recent conjunctions.\nWhile specific geometries can be identified or constructed to produce significant\nchange in Pc for the modified formulation, it is of operational interest to quanti-\nfy the relative occurrence of such cases for satellite conjunction risk...
Topics: NASA Technical Reports Server (NTRS), 6e64c82d5b5c51cda64e8bb7365d9036, Brent Skrehart, Daniel...
The National Airspace System (NAS) is evolving; it is becoming more crowded, and new vehicles with different capabilities are starting to utilize airspace. Increased capacity, new vehicles, and their varying performance and equipage profiles will require changes in how we operate in the NAS. The Crew Systems and Aviation Operations Branch (CSAOB) has actively supported crew systems and aviation research contributing to the safe evolution of the NAS. As the NAS continues to evolve to meet the...
Topics: NASA Technical Reports Server (NTRS), 68603dff261e5d2d9de5a550aa9e6b30
Research into concepts such as advanced air mobility (AAM) and urban air mobility (UAM) offers an opportunity for successfully and safely adding new classes of vehicles into the National Airspace System. However, a need exists for research into the human factors associated with these concepts. In this paper, we evaluate the gaze behaviors of three remote ground control station operators (GCSOs) conducting simulated UAM operations. The participants monitored and controlled an unmanned aircraft...
Topics: NASA Technical Reports Server (NTRS), d3417fa4ba295161bac9b0da8844d4a2, James R Unverricht,...
Delay Tolerant Networking (DTN) is the standard approach to the networking of space systems with the goal of supporting the Solar System Internet (SSI). Current space networks have a small scale and often depend on rigorously scheduled (pre-determined) contact opportunities; this manual approach inhibits scalability. The goal of this paper is to recast these scheduling problems in order to apply the optimization machinery of tropical geometry.\n\nContact opportunities in space are dependent on...
Topics: NASA Technical Reports Server (NTRS), American University, Brendan Mallery, Devavrat Vivek Dabke,...
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Topics: NASA Technical Reports Server (NTRS), 02643c9e9b525162877c70e4c186571b, D E Snow, Omitron (United...
Bacterial growth in liquid media while under microgravity conditions is not well understood. Trends such as a shortened lag phase, longer log phase, slower growth rate, and a higher final population concentration have been noted but the underlying cause remains unclear. Ground-based spaceflight analogs, or simulated microgravity devices, are often employed to achieve different attributes of weightlessness to study effects on bacterial growth. Though these technologies could isolate gravity’s...
Topics: NASA Technical Reports Server (NTRS), 5c929cce29b0585fb37efe77c6e9d156, Aubrie Orourke, Kennedy...
Diversity and Inclusion Outreach event to promote STEM, NASA, and Aeronautics to underrepresented middle school students in the Bay Area. Connect with the community. Engage with students to showcase NASA Ames Aeronautics and spark interest in a STEM education.
Topics: NASA Technical Reports Server (NTRS), 00a2a0542f9451ffac4b0aa2053787b3
A distant, massive planet in the outer solar system has recently been proposed to explain some observed features of extreme trans-Neptunian objects (TNOs). Here we use N-body simulations of the formation of the Kuiper Belt and Oort cloud as well as a survey simulator to compare models of the solar system with and without a ninth planet to one another as well as to observations. The main mechanism for TNOs to be deposited into the distant (a > 50 au), detached (q > 40 au) region of the...
Topics: NASA Technical Reports Server (NTRS), 0000-0001-5042-7123, 8245d8a89a0947b8918d59acd86b1f74,...
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Topics: NASA Technical Reports Server (NTRS), 7f9c4cf9cb6f517db6b0fb40eb584c03, Ames Research Center, Henry...
We compare various sputtering simulation methods to experimental results in both the low energy (
Topics: NASA Technical Reports Server (NTRS), 0000-0001-7860-9957, 0000-0001-8388-454X,...
External spacecraft materials play an important role in satellite protection from the harsh space environment. Research has shown that the physical, chemical, and optical properties of matter change continuously as a result of exposure to solar radiation and aggressive chemical species produced in Earth’s upper atmosphere. Thorough knowledge of the material properties evolution throughout a planned mission lifetime helps to improve the reliability of spacecraft. Moreover, the establishment of...
Topics: NASA Technical Reports Server (NTRS), 4772b345301044fdb444b43b68f02918, Alexey Sokolovskiy,...
NASA’s Artemis Program seeks not only to return humans to the Moon for the first time since the 1970’s but also to provide the technological basis for infrastructure that will enable permanent and expanding scientific and industrial exploitation of the Lunar surface. The primary purpose of this infrastructure is to generate and distribute power to a diverse and growing range of scientific and industrial assets, and the keys to success for this function are power management and control...
Topics: NASA Technical Reports Server (NTRS), 4c6a2b878d76521da887cdcb2564bf90
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Topics: NASA Technical Reports Server (NTRS), 0000-0001-8489-861X, 4c6a2b878d76521da887cdcb2564bf90
A cooperative flight test campaign between U.S. Navy, Army, Marine Corps, and NASA was performed at Marine Corps Air Station (MCAS) Yuma from 19 January to 15 February 2022. The primary purpose of testing military vehicles was to characterize the acoustic signature of the MV-22 rotorcraft and Stalker unmanned aerial system for typical mission gross weight, configuration, and for a range of typical mission operating conditions. Additionally, a civilian MD530 vehicle was tested to characterize...
Topics: NASA Technical Reports Server (NTRS), 02ac99c3135052eca2758e9d77e4826f, Analytical Mechanics...
Terrestrial snow is a vital freshwater resource for more than 1 billion people. Remotely-sensed snow observations can be used to retrieve snow mass or integrated into a snow model estimate; however, optimally leveraging remote sensing observations of snow is challenging. One reason is that no single sensor can accurately measure all types of snow because each type of sensor has its own unique limitations. Another reason is that remote sensing data is inherently discontinuous across time and...
Topics: NASA Technical Reports Server (NTRS), 0000-0001-6410-9978, 0000-0002-8594-4312,...
For nearly 40 yr, studies of exosphere formation on airless bodies have been hindered by uncertainties in our understanding of the underlying ion collisional sputtering by the solar wind (SW). These ion impacts on airless bodies play an important role in altering their surface properties and surrounding environment. Much of the collisional sputtering data needed for exosphere studies come from binary collision approximation (BCA) sputtering models. These depend on the surface binding energy...
Topics: NASA Technical Reports Server (NTRS), 0000-0001-7860-9957, 0000-0001-8388-454X,...
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Topics: NASA Technical Reports Server (NTRS), 199c40960ed646fca72ff45be92fdad6
Permanently shadowed regions (PSRs) contain some areas [Figure 1] where frozen volatiles can be observed at the lunar poles. They have maximum surface temperatures < 100 K [1, 2]. \nSurface temperatures in these shadowed regions are largely controlled by reflected sunlight and irradiated infrared light from adjacent topography [3-6]. These areas are cold traps, capable of accumulating water and other volatile compounds over time [7]. \nThere is a lack of understanding regarding the...
Topics: NASA Technical Reports Server (NTRS), 0be91b7a68665cf882c2ccee8ad03aff, C J Ahrens, Universities...
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Topics: NASA Technical Reports Server (NTRS), 68603dff261e5d2d9de5a550aa9e6b30
Conventional definitions of habitability require abundant liquid surface water to exist continuously over geologic timescales. Water in each of its thermodynamic phases interacts with solar and thermal radiation and is the cause for strong climatic feedbacks. Thus, assessments of the habitable zone require models to include a complete treatment of the hydrological cycle over geologic time. Here, we use the Community Atmosphere Model from the National Center for Atmospheric Research to study the...
Topics: NASA Technical Reports Server (NTRS), 0000-0002-1394-3062, 0000-0002-7188-1648,...
This document provides guidance for assessing similarity relative to nondestructive evaluation (NDE) detectability based on Probability of Detection demonstrations when comparing different NDE inspection situations. Differences in inspection situations addressed by the similarity assessment methodology herein can include differences in the component being inspected, and differences in the conditions for the inspection. Additional differences in the inspection situation relative to differences...
Topics: NASA Technical Reports Server (NTRS), 4c6a2b878d76521da887cdcb2564bf90,...
Abstract: Each of the giant planets, Jupiter, Saturn, Uranus, and Neptune, has been observed by at least one robotic spacecraft mission. However, these missions are infrequent; Uranus and Neptune have only had a single flyby by Voyager 2. The Hubble Space Telescope, particularly the Wide Field Camera 3 (WFC3) and Advanced Camera for Surveys (ACS) instruments, and large ground-based telescopes with adaptive optics systems have enabled high spatial resolution imaging at a higher cadence, and over...
Topics: NASA Technical Reports Server (NTRS), 0000-0001-5480-8580, 0000-0001-5834-9588,...
The Mars Ascent Vehicle (MAV) will be the first vehicle to perform an ascent from the surface of another atmospheric planetary body outside of the Earth-Moon system. Significant light-time delay requires complete autonomy of flight throughout ascent, and naturally a high level of reliability is desired in both MAV’s hardware and software subsystems. The MAV Guidance, Navigation and Controls (GNC) team and the MAV Flight Software (FSW) team have partnered together to improve the efficiency of...
Topics: NASA Technical Reports Server (NTRS), ff293352e05b51ca965411fc94f5e325
The Planet Formation Imager (PFI) project aims to provide a strong scientific vision for ground-based opticalastronomy beyond the upcoming generation of Extremely Large Telescopes. We make the case that a break-through in angular resolution imaging capabilities is required in order tounravel the processes involved in planetformation. PFI will be optimised to provide a complete census of the protoplanet population at all stellocentricradii and over the age range from 0.1 to∼100 Myr. Within...
Topics: NASA Technical Reports Server (NTRS), 0000-0001-8974-0758, 0000-0002-3481-9052,...
The NASA Human System Risk Board (HSRB) is responsible for tracking the evolution of the top ~30 human system risks identified to be associated with human spaceflight. As part of this process, the Board is charged with maintaining a consistent, integrated process to evaluate those risks and developing evidence-based risk posture recommendations. Risks are ranked by likelihood and consequence. Intermediate causal relationships between risk contributing factors and...
Topics: NASA Technical Reports Server (NTRS), 2124795aedb35b25a21b40ec1cc6d926, Ames Research Center,...
A two-part analytical study was conducted examining a small-scale, two-bladed rotor undergoing a change in rotor speed in a wind tunnel setting. First, a parametric study was conducted to understand how rotor transient response, determined using a time-marching solution, is affected by the choice of rotor wake model, blade elasticity, and inclusion of an elastic support structure model. The second part of the study compared results from an analytical model of the NASA Multirotor Test Bed (MTB)...
Topics: NASA Technical Reports Server (NTRS), 68603dff261e5d2d9de5a550aa9e6b30
The High-rate Delay Tolerant Networking (HDTN) project at the NASA Glenn Research Center (GRC) is developing a performance-optimized Delay Tolerant Networking (DTN) implementation using the Bundle Protocol (BP) both for infusion in modern, distributed spacecraft systems and for foundational network research purposes.\n\nWhile one purpose of networking is to enable a returns-to-scale with communicating assets, it is recognized that neither the protocol nor its implementations may impose a...
Topics: NASA Technical Reports Server (NTRS), Blake LaFuente, fdea3daf3b5156699f511edf3e9b9ec4, Glenn...
The non-resonant Kuiper belt objects between the 3:2 and 2:1 Neptunian mean motion resonances can be largely divided between a cold classical belt (CCB) and a hot classical belt (HCB). A notable difference between these two subpopulationsis the prevalence of widely spaced, equal-mass binaries in the CCB, and a much smaller but non-zero number in the HCB.The primary reason for this difference in binary rate remains unclear. Here usingN-body simulations we examine whetherclose encounters with the...
Topics: NASA Technical Reports Server (NTRS), e51c5d097a0b48c5b4bdf957722f9c89, Lukas R Stone, Nathan A...
The Mars Sample Return campaign aims at bringing back soil, rock and atmospheric samples from Mars to Earth to answer key questions about Mars’ biological evolution by means of four missions. The first one, Mars 2020, landed on the red planet on February 18, 2021 and has to date collected a number of samples through the Perseverance rover. The three subsequent missions will recover the sample tubes, launch them into Mars orbit and transport them back to Earth. These missions are currently in...
Topics: NASA Technical Reports Server (NTRS), e081fcbdcd5059fa8fa7b6c5c6a2c483
As NASA software systems continue to innovate, becoming more complex and nondeterministic, the need for the NASA IV&V Program to become systemically adaptive to ensure mission success is paramount. To ensure adaptability within resource constraints, IV&V has developed an agile, risk-based approach to identify, characterize, scope, focus, and prioritize mission assurance activities. This risk based adaptive framework has been applied to trends such as increased reliance on data driven...
Topics: NASA Technical Reports Server (NTRS), 84f35d8ac3544d8aae8995fce357023a
This paper describes an ongoing effort to embed and verify differential dynamic logic (dL) in the Prototype Verification System (PVS). dL is a logic for specifying and formally reasoning about hybrid systems, which employ both continuous and discrete dynamics. There are several benefits of this effort. First, the embedding of dL in PVS offers an independent formal verification of the semantics and rules of dL. Second, the embedding is fully operational within PVS, giving PVS practitioners the...
Topics: NASA Technical Reports Server (NTRS), 68603dff261e5d2d9de5a550aa9e6b30, Langley Research Center,...
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