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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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At least 217 records · Page 12

Development of NASA's Small Fission Power System for Science and Human Exploration

Exploration of our solar system has brought great knowledge to our nation's scientific and engineering community over the past several decades. As we expand our visions to explore new, more challenging destinations, we must also expand our technology base to support these new missions. NASA's Space Technology Mission Directorate is tasked with developing these technologies for future mission infusion and continues to seek answers to many existing technology gaps. One such technology gap is related to compact power systems (greater than 1 kWe) that provide abundant power for several years where solar energy is unavailable or inadequate. Below 1 kWe, Radioisotope Power Systems have been the workhorse for NASA and will continue, assuming its availability, to be used for lower power applications similar to the successful missions of Voyager, Ulysses, New Horizons, Cassini, and Curiosity. Above 1 kWe, fission power systems become an attractive technology offering a scalable modular design of the reactor, shield, power conversion, and heat transport subsystems. Near term emphasis has been placed in the 1-10kWe range that lies outside realistic radioisotope power levels and fills a promising technology gap capable of enabling both science and human exploration missions. History has shown that development of space reactors is technically, politically, and financially challenging and requires a new approach to their design and development. A small team of NASA and DOE experts are providing a solution to these enabling FPS technologies starting with the lowest power and most cost effective reactor series named "Kilopower" that is scalable from approximately 1-10 kWe.

Solar System↗

Analyzing Space Weather at Mars with MAVEN

To understand the processes driving Martian atmospheric escape to space, the MAVEN mission has been monitoring solar inputs at Mars since the spacecraft went into orbit in September 2014. MAVEN’s payload provides in situ measurements of solar wind ions and electrons, solar energetic particles, extreme ultraviolet radiation, and magnetic fields. With this comprehensive suite of instruments, the MAVEN team has monitored space weather at Mars for nearly a decade, over various parts of Solar Cycles 24 and 25. MAVEN observations have determined that space weather activity can deposit enough energy into the Martian system to enhance atmospheric escape by an order of magnitude. As the mission continues, monitoring space weather at Mars has become increasingly important to understand the Sun’s influence on the Martian environment. The MAVEN team provides regular reports of space weather activity, such as the occurrence and arrival time of coronal mass ejections as well as flare magnitude and peak times, to the Mars community when predictions suggest that a space weather-impacting event may be directed towards Mars. MAVEN provides observations of solar activity on the ‘far side’ of the Sun when Earth and Mars are near solar conjunction to augment measurements of solar observatories (e.g., SDO, STEREO, GOES, PSP, Solar Orbiter), providing a more global coverage of solar activity. Additionally, MAVEN is working closely with the Community Coordinated Modeling Center (CCMC) and the Moon to Mars (M2M) Space Weather Analysis Office, both located at NASA GSFC, to form the Mars Space Weather Collaboration. This collaboration utilizes MAVEN observations of space weather activity to facilitate model and prediction validation while creating tools that are available to the science community. These activities are in support of future human and robotic exploration as we identify needs to enhance current capabilities for analyzing space weather at Mars.

Gina A DiBraccio↗

Solar and Heliospheric Modeling at the CCMC

The CCMC has three principal functions, 1) To test and validate model in use in the research community that are destined for a future Space Weather forecasting role, 2) To make them available for wider use in the research community, and 3) To assist in transitioning these models to Rapid Prototyping Centers. Beginning in 2000 with a small model inventory, the CCMC now hosts more than 40 models or model combinations, covering the solar atmosphere, heliosphere, magnetosphere and ionosphere. In this talk I will describe the solar and heliospheric modeling component, its history, its current status and our future plans.

Source record↗

Space Weather Modeling Services at the Community Coordinated Modeling Center

The Community Coordinated Modeling Center (CCMC) is a multi-agency partnership, which aims at the creation of next generation space weather models. The goal of the CCMC is to support the research and developmental work necessary to substantially increase the present-day modeling capability for space weather purposes, and to provide models for transition to the Rapid Prototyping Centers at the space weather forecast centers. This goal requires close collaborations with and substantial involvement of the research community. The physical regions to be addressed by CCMC-related activities range from the solar atmosphere to the Earth's upper atmosphere. The CCMC is an integral part of the National Space Weather Program Implementation Plan, of NASA's Living With a Star (LWS) initiative, and of the Department of Defense Space Weather Transition Plan. CCMC includes a facility at NASA Goddard Space Flight Center. CCMC also provides, to the research community, access to state-of-the-art space research models. In this paper we will provide a description of the current CCMC status, discuss current plans, research and development accomplishments and goals, and describe the model testing and validation process undertaken as part of the CCMC mandate. Special emphasis will be on solar and heliospheric models currently residing at CCMC, and on plans for validation and verification.

Hesse, Michael↗

MODIS Reflective Solar Bands On-Orbit Calibration and Performance

The design of the MODIS instrument was driven by the scientific community's desire to have near-daily global coverage at moderate resolution (1 km) with a comprehensive spectral coverage from visible to long-wave infrared wavelengths. Since their launches in 1999 and 2002, respectively, the Terra and Aqua MODIS instruments have made continuous global observations and generated numerous data products to help users worldwide with their studies of the Earth's system and its short- and long-term changes. The 20 reflective solar bands (RSB) with wavelengths from 0.41 to 2.2 m collect data at three nadir spatial resolutions: 250 m, 500 m, and 1 km. The solar diffuser (SD) coupled with the solar diffuser stability monitor (SDSM) provide a reflectance-based calibration on-orbit. In addition, lunar observations and response trends from pseudo-invariant desert sites are used to characterize the response versus scan- angle changes on-orbit. This paper provides a brief overview of MODIS RSB calibration algorithms, as implemented in the latest Level 1B version 6.1, operational activities, on-orbit performance, remaining challenges and potential improvements. Results from the SD and SDSM measurements show a wavelength and mirror side dependent degradation in RSB responses, with the largest degradation at the shortest wavelengths, particularly for Terra MODIS. Aqua MODIS has experienced far less degradation of its optics and on-board calibrators compared to Terra MODIS, resulting in an overall better performance. With the exception of Aqua band 6, there have been no new noisy or inoperable detectors in the RSB of either instrument during post-launch operations. As the instruments age and continue to endure the space environment, the detectors and optical systems degrade. The challenges associated with incorporating these on-orbit changes to ensure a production of high-quality calibrated L1B data products are also discussed in this paper.

solar diffuser stability monitor↗

The NASA IRTF: Solar System Observations and Mission Support

This report covers the period from 1 July 2002 through 30 June 2003. The NASA Infrared Telescope Facility (IRTF) is a 3.0 m infrared telescope located at an altitude of 4.2 km on the summit of Mauna Kea in Hawaii. It was established by NASA in 1979 primarily to provide infrared observations in support of NASA's programs. The IRTF is managed and operated by the University of Hawaii (UH) Institute for Astronomy (IfA) under a five-year cooperative agreement between NASA and UH that started in February 2001. NASA provides the costs of operation, and NSF provides support for new focal plane instrumentation based on grant applications from IRTF support astronomers. Observing time is open to the entire astronomical community, and 50% of the IRTF observing time is reserved for studies of solar system objects.

Kudritzki, Rolf-Peter↗

Space Weather Modeling at the Community Coordinated Modeling Center

The Community Coordinated Modeling Center (CCMC) is a multi-agency partnership, which aims at the creation of next generation space weather models. The goal of the CCMC is to support the research and developmental work necessary to substantially increase the present-day modeling capability for space weather purposes, and to provide models for transition to the rapid prototyping centers at the space weather forecast centers. This goal requires dose collaborations with and substantial involvement of the research community. The physical regions to be addressed by CCMC-related activities range from the solar atmosphere to the Earth's upper atmosphere. The CCMC is an integral part of the National Space Weather Program Implementation Plan, of NASA's Living With a Star (LWS) initiative, and of the Department of Defense Space Weather Transition Plan. CCMC includes a facility at NASA Goddard Space Flight Center, as well as distributed computing facilities provided by the US Air Force. CCMC also provides, to the research community, access to state-of-the-art space research models. In this paper we will provide updates on CCMC status, on current plans, research and development accomplishments and goals, and on the model testing and validation process undertaken as part of the CCMC mandate. Special emphasis will be on solar and heliospheric models currently residing at CCMC, and on plans for validation and verification.

Hesse M.↗

Using Time Series Data Products to Support ASHRAE’s Historic and Future Climate Data Needs through NASA’s POWER Web Services

To address the data needs for resilience and sustainability of building systems within ASHRAE, the NASA Prediction of Worldwide Energy Resource (POWER) project facilitates the use of NASA Earth Science data on a long-term, global scale. Solar data from several NASA projects and meteorological data from NASA assimilation models have been reformatted and disseminated to the public via a user friendly web GIS-enabled based data portal (https://power.larc.nasa.gov) in selectable data formats, immediately amenable to key industry wide decision support tools such as EnergyPlus. Time series of potential climate conditions from downscaled climate simulations are being made available for similar statistics and formats. An emphasis is placed upon obtaining and utilizing time series data to conduct analysis of building system performance for current and planning building systems for energy savings and greenhouse gas emissions. This presentation has the learning following learning objectives for the ASHRAE community: 1) Learn how NASA POWER’s web service suite can provide supplementary solar and surface meteorological data parameters, including a discussion of uncertainty. 2) Learn how downscaled climate scenario information can be provided to evaluate potential future requirements. The presentation is part of a forum entitled, "Weather Data for Large-Scale Building Energy Modeling".

time series↗

Aspects of Coronal Mass Ejections Related to Space Weather

Solar cycle 23 witnessed an unprecedented array of space- and ground-based instruments observing the violent eruptions from the Sun that had huge impact on the heliosphere. It was possible to characterize corona) mass ejections (CMEs) that cause extreme solar energetic particle events and geomagnetic storms, the two aspects that concern the space weather community. In this paper I discuss the special populations of CMEs that have significant interplanetary consequences: shock-driving CMEs identified based on their association with type 11 radio bursts and in-situ shocks, SEP-producing CMEs, and geoeffective CMEs (those that produce geomagnetic storms). I discuss the kinematic and solar-source properties of these populations and how they vary with the solar activity cycle. I also compare their properties with the general population of CMEs, so one can recognize when and where these events occur on the Sun.

Gopalswamy, Nat↗

Space solar cell research: Problems and potential

The value of a passive, maintenance-free, renewable energy source was apparent in the early days of the space program, and the silicon solar cell was pressed into service. Efficiencies of those early space solar arrays were low, and lifetimes shorter than hoped for, but within a decade significant advances had been made in both areas. Better performance was achieved through improvements in silicon single crystal material, better device designs, and a better understanding of the factors that affect the performance of a solar cell in space. Chief among the latter, particularly for the mid-to-high altitude (HEO) and geosynchronous (GEO) orbits, are the effects of the naturally occurring particulate radiation environment. Although not as broadly important to the photovoltaic community at large as increased efficiency, the topic of radiation damage is critically important to use of solar cells in space, and is a major component of the NASA research program in space photovoltaics. A brief overview of some of the opportunities and challenges for space photovoltaic applications is given, and some of the current research directed at achieving high efficiency and controlling radiation damage in space solar cells is discussed.

Flood, D. J.↗

Space solar cell research - Problems and potential

The value of a passive, maintenance-free, renewable energy source was immediately recognized in the early days of the space program, and the silicon solar cell, despite its infancy, was quickly pressed into service. Efficiencies of those early space solar arrays were low, and lifetimes shorter than hoped for, but within a decade significant advances had been made in both areas. Better performance was achieved because of a variety of factors, ranging from improvements in silicon single crystal material, to better device designs, to a better understanding of the factors that affect the performance of a solar cell in space. Chief among the latter, particularly for the mid-to-high altitude (HEO) and geosynchronous (GEO) orbits, are the effects of the naturally occurring particulate radiation environment. Although not as broadly important to the photovoltaic community at large as increased efficiency, the topic of radiation damage is critically important to use of solar cells in space, and is a major component of the NASA research program in space photovoltaics. This paper will give a brief overview of some of the opportunities and challenges for space photovoltaic applications, and will discuss some of the current reseach directed at achieving high efficiency and controlling the effects of radiation damage in space solar cells.

Flood, Dennis J.↗

Characterization of Spacesuit Associated Microbial Communities and their Implications for NASA Missions

Crewed National Aeronautics and Space Administration (NASA) missions to other solar system bodies are currently being planned. One high-profile scientific focus during such expeditions would be life detection, specifically the discovery of past or present microbial life, if they exist. However, both humans and associated objects typically carry a high microbial burden. Thus, it is essential to distinguish between microbes brought with the expedition and those present on the exploring planets. Modern spacesuits are unique, customized spacecraft which provide protection, mobility and life support to crew during spacewalks, yet they vent continuously, and the mobility of microbes through spacesuits has not been studied. To evaluate the microbial colonization of spacesuits, NASA used an Extravehicular Activity swab kit to examine viable microbial populations of 48 samples from spacesuits using both traditional microbiological methods and molecular sequencing methods. The cultivable microbial population ranged from below the detection limit to 9 x 102 colony forming units per 25 cm2 of sample and also significantly varied by the location. The cultivable microbial diversity was dominated by members of Bacillus, Arthrobacter, and Ascomycota. However, 16S rRNA-based viable bacterial burden ranged from 105 to 106 copies per 25 cm2 of sample. Shotgun metagenome sequencing revealed the presence of a diverse microbial population on the spacesuit surfaces, including Curtobacterium and Methylobacterium from across all sets of spacesuits in high abundance. Among bacterial species identified, higher abundance of Cutibacterium acnes, Methylobacterium oryzae, and M. phyllosphaerae reads were documented. The results of this study provide evidence that identical microbial strains may live on the wrist joint, inner gauntlet, and outer gauntlet of spacesuits. This raises the possibility, but does not confirm, that viable microbes are able to migrate between the interior and exterior of spacesuits. Overall, these data provide the first estimate of microbial dispersion from internal to external spacesuit surfaces, which will help future mission planners develop effective planetary protection strategies.

spacesuit↗

Terrestrial photovoltaic measurements

Revised measurement and calibration procedures are available. ERDA workshop utilized experience gained in solar cell research to define and explore additional measurement needs of photovoltaic community. Interim measurement procedures previously established were revised and published in manual in addition to other procedures.

Brandhorst, H. W., Jr.↗

The NASA Solar Probe mission - In situ determination of interplanetary out-of-the ecliptic and near-solar dust environments

The NASA Solar Probe mission will be one of the most exciting dust missions ever flown and will lead to a revolutionary advance in our understanding of dust within our solar system. Solar Probe will map the dust environment from the orbit of Jupiter (5 AU), to within 4 solar radii of the sun's center. The region between 0.3 AU and 4 Rs has never been visited before, so the ten days that the spacecraft spends during each (of the two) orbit is purely exploratory in nature. Solar Probe will also reach heliographic latitudes as high as about 15 to 28 deg above (below) the ecliptic on its trajectory inbound (outbound) to (from) the sun. This, in addition to the ESA/NASA Ulysses mission, will help determine the out-of-the-ecliptic dust environment. A post-perihelion burn will reduce the satellite orbital period to 2.5 years about the sun. A possible extended mission would allow data reception for two more revolutions, mapping out a complete solar cycle. Because the near-solar dust environment is not well understood (or is controversial at best), and it is very important to have better knowledge of the dust environment to protect Solar Probe from high velocity dust hits, we urgently request the scientific community to obtain further measurements of the nearsolar dust properties.

Tsurutani, Bruce T.↗

The Biogeochemistry of Benthic Photosynthetic Communities

Microbial mats are our earliest, and most pervasive evidence of life on Earth. In addition to their importance as the crucible of microbial evolution on Earth, microbial mats may be important in our search for life outside of our solar system. This lecture will introduce various types of microbial mats, and their fossilized counterparts, stromatolites by presenting examples of these communities. Biogeochemical cycles important in microbial mats will be introduced and discussed.

Bebout, Brad↗

17th Space Photovoltaic Research and Technology Conference

The 17th Space Photovoltaic Research and Technology (SPRAT XVII) Conference was held September 11-13, 2001, at the Ohio Aerospace Institute (OAI) in Cleveland, Ohio. The SPRAT conference, hosted by the Photovoltaic and Space Environments Branch of the NASA Glenn Research Center, brought together representatives of the space photovoltaic community from around the world to share the latest advances in space solar technology. This year's conference continued to build on many of the trends shown in SPRAT XVI; the use of new high-efficiency cells for commercial use and the development of novel array concepts such as Boeing's Solar Tile concept. In addition, new information was presented on space environmental interactions with solar arrays.

Jenkins, Phillip↗

18th Space Photovoltaic Research and Technology Conference

The 18th Space Photovoltaic Research and Technology (SPRAT XVIII) Conference was held September 16 to 18, 2003, at the Ohio Aerospace Institute (OAI) in Brook Park, Ohio. The SPRAT conference, hosted by the Photovoltaic and Space Environments Branch of the NASA Glenn Research Center, brought together representatives of the space photovoltaic community from around the world to share the latest advances in space solar cell technology. This year s conference continued to build on many of the trends shown in SPRAT XVII-the continued advances of thin-film and multijunction solar cell technologies and the new issues required to qualify those types of cells for space applications.

Morton, Thomas L.↗

CFD Multiphysics Tool

The recent bold initiatives to expand the human presence in space require innovative approaches to the design of propulsion systems whose underlying technology is not yet mature. The space propulsion community has identified a number of candidate concepts. A short list includes solar sails, high-energy-density chemical propellants, electric and electromagnetic accelerators, solar-thermal and nuclear-thermal expanders. For each of these, the underlying physics are relatively well understood. One could easily cite authoritative texts, addressing both the governing equations, and practical solution methods for, e.g. electromagnetic fields, heat transfer, radiation, thermophysics, structural dynamics, particulate kinematics, nuclear energy, power conversion, and fluid dynamics. One could also easily cite scholarly works in which complete equation sets for any one of these physical processes have been accurately solved relative to complex engineered systems. The Advanced Concepts and Analysis Office (ACAO), Space Transportation Directorate, NASA Marshall Space Flight Center, has recently released the first alpha version of a set of computer utilities for performing the applicable physical analyses relative to candidate deep-space propulsion systems such as those listed above. PARSEC, Preliminary Analysis of Revolutionary in-Space Engineering Concepts, enables rapid iterative calculations using several physics tools developed in-house. A complete cycle of the entire tool set takes about twenty minutes. PARSEC is a level-zero/level-one design tool. For PARSEC s proof-of-concept, and preliminary design decision-making, assumptions that significantly simplify the governing equation sets are necessary. To proceed to level-two, one wishes to retain modeling of the underlying physics as close as practical to known applicable first principles. This report describes results of collaboration between ACAO, and Embry-Riddle Aeronautical University (ERAU), to begin building a set of level-two design tools for PARSEC. The "CFD Multiphysics Tool" will be the propulsive element of the tool set. The name acknowledges that space propulsion performance assessment is primarily a fluid mechanics problem. At the core of the CFD Multiphysics Tool is an open-source CFD code, HYP, under development at ERAU. ERAU is renowned for its undergraduate degree program in Aerospace Engineering the largest in the nation. The strength of the program is its applications-oriented curriculum, which culminates in one of three two-course Engineering Design sequences: Aerospace Propulsion, Spacecraft, or Aircraft. This same philosophy applies to the HYP Project, albeit with fluid physics modeling commensurate with graduate research. HYP s purpose, like the Multiphysics Tool s, is to enable calculations of real (three-dimensional; geometrically complex; intended for hardware development) applications of high speed and propulsive fluid flows.

Perrell, Eric R.↗