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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 37 records · Page 2
All sourcesNASA NTRSDOE OSTI
NASA NTRS2007

The NASA Space Environments and Effects Program (SEE): Over a Decade of Useful Products for Spacecraft Designers and Operators

SEE program management originated at LaRC in the early 1990's but was transferred to MSFC in FY 1995 and has remained at Marshall since that time, SEE uses 5 technical working groups and NRA's (three since 1994) to achieve its technical objectives. The SEE vision is to develop and maintain a preeminent program in SPACE ENVIRONMENTS AND EFFECTS which provides a coordinated national focus for innovative technology development to support design, development, and operation of spacecraft systems that will accommodate or mitigate effects due to the presence of the space environment. In working toward that goal, SEE has produced, through the years, over 30 major Space Environments and Effects Models and Databases, over 75 major Space Environments and Effects Publications, a website that has had over 112,000 hits since its inception (http://see.msfc.nasa.gov/), distribution of physical products that amounts to over a total of over 260 product deliveries, sponsorship of the last four international Spacecraft Charging Technology Conferences (the major subject matter conference in the world), and sponsorship of numerous technical standards and guidelines in the Space Environments area. Among the recent popular SEE products are the Electric Propulsion Interactions Code (EPIC), the NASA/Air Force Spacecraft Charging Analysis Program (NASCAP-2K), the Interactive Spacecraft Charging Handbook, the Cosmic Ray Effects on Microelectronics Code (CREME 96), the Spacecraft Contamination and Materials Outgassing Effects Knowledge base (SCMOEK), and the Lunar E-Library.

Ferguson, Dale C.↗
NASA NTRS2008

Are Current SEE Test Procedures Adequate for Modern Devices and Electronics Technologies?

Believe it or not, this has been a simplistic look at starting a checklist for SEE testing. Given a memory that has 68 operating modes, when a SEU occurs that changes the mode, just how do you determine what's going on? Laser and microbeam tests can help, but not easily for modern packaged devices. Expanding this approach to other more complex devices such as ADCs or processors as well as analog devices should be considered. The recommendation is to use the existing text standards as the starting point. Just make your own checklist for the device/technology/issues being considered. At HEART 2007, we presented some of the burgeoning challenges associated with single event effect(SEE) testing of modern commercial memories: a) Package, device complexity, test fixture, and data analysis issues were discussed; b) "Complete" SEE Characterization would take 15 years; c) Qualification test costs have a greater than 4 times increase over the last decade. In this talk, we continue to explore the roles of technology with an emphasis on the existing SEE Test Procedures and some of the concerns related to modern devices. The primary objective of the briefing is to provide some overarching guidance concerning the many considerations involved in the formulation of a SEE test plan provided in a " Checklist" format.we note that there is no such thing as a complete check list and that the best approach is to develop a flexible test plan that takes into account the device type and functions, the device technology, circuit and package design, and, of course, test facility and beam characteristics.

LaBel, Kenneth A.↗
DOE OSTI2025

Measuring Local Turbulence Along the Optical Path: Multi-Beam Optical Seeing Sensor

Deflection of light along the optical path is a major source of image degradation for ground-based telescopes. Methods have been developed to measure upper atmospheric seeing based on models of the turbulence in the atmosphere, but due to boundary conditions, transmission within telescope enclosures is more complex. The Multi-beam Optical Seeing Sensor (MOSS) directly measures the component of the image quality degradation from inhomogeneity of the index of refraction within the telescope dome. MOSS outputs four near-parallel beams of light that travel along the optical path and are imaged by the telescope’s detector, landing like starlight on the telescope’s focal plane. By using a strobed light source, we can ‘freeze’ the instantaneous index variations transverse to the optical path. This system captures both ‘dome’ and ‘mirror’ seeing. Through plotting the standard deviation of differential motion between pairs of beams, MOSS enables characterization of the length scale of turbulence within the dome. The temporal coherence of temperature gradients can be probed with different pulse lengths, and the spatial coherence by comparing pairs at different separations across the aperture of the telescope. Optical path turbulence measurements, alongside other telemetry metrics, will guide thermal and airflow management to optimize image quality. A MOSS prototype was installed in the 1.2[Formula: see text]m Auxiliary Telescope (AuxTel) at the Vera C. Rubin Observatory in Chile, and preliminary data constrain the optical path turbulence with a lower bound of 1.4 arcsec. The optical path turbulence varied throughout the night of observing.

Astronomical seeing↗
DOE OSTI2021

Strobed imaging as a method for the determination and diagnosis of local seeing

ABSTRACT The image quality budget of many telescopes can have substantial contributions from local seeing, both ‘mirror’ and ‘dome’, which arise from turbulence and temperature variations that are difficult to quantify, measure directly, and ameliorate. We describe a method to determine the ‘local’ seeing degradation due to wavefront perturbations within the final few metres of the optical path from celestial sources to the focal plane of a ground-based telescope, using the primary instrument and along the same path taken by light from celestial sources. The concept involves placing strobed emitters along the light path to produce images on the main focal plane that ‘freeze’ different realizations of index perturbations. This method has the advantage of measuring directly the image motion and scintillation imparted by the dynamic spatial and temporal structure of local perturbations in the index of refraction along the light path, with a clean separation from seeing induced in the atmosphere above the dome. The strobed-source approach allows for rapid image motion and scintillation to be measured directly on the focal plane, even for large-aperture telescopes with wide-field instruments and slow shutters, such as that being constructed for the Rubin Observatory. A conceptual design is presented that uses the ‘guider’ CCDs in the Rubin telescope focal plane to make local-seeing measurements on demand, perhaps even during science exposures.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2024

The Single Event Error (SEE) test and analysis of the CMS Endcap Timing Layer readout chip

The ETROC2, the first full size and full functionality prototype chip for the CMS Endcap Timing Layer readout, is strategically designed to meet the SEE immunity requirements of detector operation with the low power constraint. The triplicated periphery and pixel I2C configuration registers are designed with self-correction feature. The pixel readout control is centralized in the global readout and fully triplicated. The pixel readout is not triplicated, instead protected with power-efficient one-bit correction Hamming code. The TMR protection of the on-pixel threshold calibration can be turned off allowing the detection of the beam spot during the beam test by checking the bit-flips of the internal memory cells. In the initial proton beam test in January 2024, the chip readout process did not hang throughout the tests. The Hamming code correction strategy works because the error corrected TDC data were observed in the data frames. The error-injection simulation is performed to analy ze the small number of bit-flips in the configuration registers. We also performed SEE testing with a heavy ion beam in April and the data analysis is ongoing. The detailed design on the SEE immunity and the testing as well as simulation results will be presented, including follow-up SEE testing results in May and June 2024.

Gong, Datao↗
DOE OSTI2021

Do Impulsive Solar-Energetic-Electron (SEE) Events Drive High-Voltage Charging Events on the Nightside of the Moon?

When the Earth’s moon is in the supersonic solar wind, the darkside of the Moon and the lunar plasma wake can be very dangerous charging environments. In the absence of photoelectron emission (dark) and in the absence of cool plasma (wake), the emission or collection of charge to reduce electrical potentials is difficult. Unique extreme charging events may occur during impulsive solar-energetic-electron (SEE) events when the lunar wake is dominated by relativistic electrons, with the potential to charge and differentially charge objects on and above the lunar surface to very-high negative electrical potentials. In this report the geometry of the magnetic connections from the Sun to the lunar nightside are explored; these magnetic connections are the pathways for SEEs from the Sun. Rudimentary charging calculations for objects in the relativistic-electron environment of the lunar wake are performed. To enable these charging calculations, secondary-electron yields for impacts by relativistic electrons are derived. Needed lunar electrical-grounding precautions for SEE events are discussed. Calls are made 1) for future dynamic simulations of the plasma wake in the presence of time-varying SEE-event relativistic electrons and time-varying solar-wind magnetic-field orientations and 2) for future charging calculations in the relativistic-electron wake environment and on the darkside lunar surface.

79 ASTRONOMY AND ASTROPHYSICS↗
NASA NTRS2005

Virtex-II Pro PowerPC SEE Characterization Test Methods and Results

The Xilinx Vix-11 Pro is a platform FPGA that embeds multiple microprocessors within the fabric of an SRAM-based reprogrammable FPGA. The variety and quantity of resources provided by this family of devices make them very attractive for spaceflight applications. However,these devices will be susceptible to single event effects (SEE), which must be mitigated. Observations from prior testing of the Xilinx Virtex-II Pro suggest that the PowerPC core has significant vulnerability to SEES. However, these initial tests were not designed to exclusively target the functionality of the PowerPC, therefore making it difficult to distinguish processor upsets from fabric upsets. The main focus of this paper involves detailed SEE testing of the embedded PowerPC core. Due to the complexity of the PowerPC, various custom test applications, both static and dynamic, will be designed to isolate each Unit of the processor. Collective analysis of the test results will provide insight into the exact upset mechanism of the PowerPC. With this information, mitigations schemes can be developed and tested that address the specific susceptibilities of these devices. The test bed will be the Xilinx SEE Consortium Virtex-II Pro test board, which allows for configuration scrubbing, design triplication, and ease of data collection. Testing will be performed at the Indiana University Cyclotron Facility using protons of varying energy levels and fluencies. This paper will present the detailed test approach along with the results.

Petrick, David↗
NASA NTRS2007

Statistical Properties of SEE Rate Calculation in the Limits of Large and Small Event Counts

This viewgraph presentation reviews the Statistical properties of Single Event Effects (SEE) rate calculations. The goal of SEE rate calculation is to bound the SEE rate, though the question is by how much. The presentation covers: (1) Understanding errors on SEE cross sections, (2) Methodology: Maximum Likelihood and confidence Contours, (3) Tests with Simulated data and (4) Applications.

Ladbury, Ray↗
NASA NTRS2013

Space Environments and Effects Program (SEE)

The need to preserve works and NASA documented articles is done via the collection of various Space Environments and Effects (SEE) related articles. (SEE) contains and lists the various projects that are ongoing, or have been conducted with the help of NASA. The goal of the (SEE) program is to make publicly available the environment technologies that are required to design, manufacture and operate reliable, cost-effective spacecraft for the government and commercial sectors. Of the many projects contained within the (SEE) program the Lunar-E Library and Spacecraft Materials Selector (SMS) have been selected for a more user friendly means to make the tools easily available to the public. This information which is still available required a person or entity to request access from a point of contact at NASA and wait for the requested bundled software DVD via postal service. Redesigning the material presentation and availability has been mapped to a single step process with faster turnaround time via Materials and Processes Technical Information System (MAPTIS) database. This process requires users to register and be verified in order to gain access to the information contained within. Aiding in the progression of making the software tools/documents available required a combination of specialized in-house data gathering software tools and software archeology.

Yhisreal-Rivas, David M.↗
NASA NTRS2017

Strategies for SEE Hardness Assurance - From Buy-It-And-Fly-It to Bullet Proof

This part of the course first outlines the conventional Single Event Effect (SEE), radiation hardness assurance (RHA) approach, which emphasizes mission success. Next, Dr. Ladbury will discuss the challenges posed by new satellite platforms (e.g., cubesats, nanosats, etc.), where cost and schedule receive emphasis equal to if not greater than mission success. These additional pressures, along with growing demands to reduce size, weight and power, coupled with increased performance, drive many projects toward expanding their use of commercial-off-the-shelf (COTS) technologies. While this may reduce direct parts cost and procurement lead times, it undermines many cost-reduction strategies used for conventional SEE RHA and can make radiation testing and analysis one of the most significant risks or worse, a risk neglected altogether. That section will end with some approaches for restoring balance in the troika of mission success, cost, and schedule. This is captured in SEE RHA as risk management: identify the threat, evaluate the threat, and mitigate the threat.

commercial-off-the-shelf (COTS)↗
NASA NTRS2017

Strategies for SEE Hardness Assurance From Buy-It-And-Fly-It to Bullet Proof

This part of the course first outlines the conventional Single Event Effect (SEE), radiation hardness assurance (RHA) approach, which emphasizes mission success. Next, Dr. Ladbury will discuss the challenges posed by new satellite platforms (e.g., cubesats, nanosats, etc.), where cost and schedule receive emphasis equal to if not greater than mission success. These additional pressures, along with growing demands to reduce size, weight and power, coupled with increased performance, drive many projects toward expanding their use of commercial-off-the-shelf (COTS) technologies. While this may reduce direct parts cost and procurement lead times, it undermines many cost-reduction strategies used for conventional SEE RHA and can make radiation testing and analysis one of the most significant risksor worse, a risk neglected altogether. That section will end with some approaches for restoring balance in the troika of mission success, cost, and schedule. This is captured in SEE RHA as risk management: identify the threat, evaluate the threat, and mitigate the threat.

commercial-off-the-shelf (COTS)↗
NASA NTRS2018

NASA Electronic Parts and Packaging (NEPP) Field Programmable Gate Array (FPGA) Single Event Effects (SEE) Test Guideline Update

The following are updated or new subjects added to the FPGA SEE Test Guidelines manual: academic versus mission specific device evaluation, single event latch-up (SEL) test and analysis, SEE response visibility enhancement during radiation testing, mitigation evaluation (embedded and user-implemented), unreliable design and its affects to SEE Data, testing flushable architectures versus non-flushable architectures, intellectual property core (IP Core) test and evaluation (addresses embedded and user-inserted), heavy-ion energy and linear energy transfer (LET) selection, proton versus heavy-ion testing, fault injection, mean fluence to failure analysis, and mission specific system-level single event upset (SEU) response prediction. Most sections within the guidelines manual provide information regarding best practices for test structure and test system development. The scope of this manual addresses academic versus mission specific device evaluation and visibility enhancement in IP Core testing.

Test guidelines↗
NASA NTRS1974

Seeing - Its cause and cure

Following Fried, the statistics of images formed by an annular telescope aperture looking through the turbulent atmosphere are calculated; the deleterious effect of a central obscuration is much larger in the presence of seeing that for the telescope alone. A method of optimizing resolution through the atmosphere is explained in detail, with particular attention to the requirements for image-motion compensation; under ideal conditions, about a factor-of-four increase in effective resolution over conventional photography can be obtained. The effective resolution can be large or smaller than the 'seeing disk', depending on the recorded signal-to-noise ratio. Some common misconceptions about image structure and motion, and various unsound proposals for beating the seeing, are criticized.

Young, A. T.↗
NASA NTRS1978

The wavelength dependence of seeing

The deleterious effects of atmospheric inhomogeneities on telescope angular resolution (seeing effects) were studied at a wavelength of 10 microns with an imaging upconverter. Seeing was found to be systematically better by a factor of 1.9 at 10 microns than in the visible, in good agreement with theoretical predictions. A discussion of the theory of astronomical seeing is included.

Boyd, R. W.↗
NASA NTRS1980

The effects of seeing on the reflected spectrum of Uranus and Neptune

The results of a redetermination of the rotational periods of Uranus and Neptune, based on spectrograms obtained with the coude spectrograph of the 5 m Hale telescope, are presented. The effects of image motion on the shape of the spectral lines reflected by a planet rotating as a solid body and coherently scattering solar light, has been studied analytically. A general relation between the seeing transformed velocities at any point on the disk and those at the equator is established. It is shown that, for the case of Gaussian seeing, the brightness continuum of the smeared disk contains all the information required to derive the shape of the reflected lines. The shift, change in r.m.s. width, and asymmetry of the seeing transformed lines at the equator have been numerically evaluated for the brightness distribution of Uranus determined from Stratoscope II.

Muench, G.↗
NASA NTRS1986

Test processing system (SEE)

The SEE data processing system, developed in 1985, manages and process test results. General information is provided on the SEE system: objectives, characteristics, basic principles, general organization, and operation. Full documentation is accessible by computer using the HELP SEE command.

Gaulene, P.↗
NASA NTRS1999

NASA's Space Environments and Effects (SEE) Program: Contamination Engineering Technology Development

ABSTRACT The return of the Long Duration Exposure Facility (LDEF) in 1990 brought a wealth of space exposure data on materials, paints, solar cells, etc. and data on the many space environments. The effects of the harsh space environments can provide damaging or even disabling effects on spacecraft, its materials, and its instruments. In partnership with industry, academia, and other government agencies, National Aeronautics & Space Administration's (NASA's) Space Environments & Effects (SEE) Program defines the space environments and provides technology development to accommodate or mitigate these harmful environments on the spacecraft. This program provides a very comprehensive and focused approach to understanding the space environment, to define the best techniques for both flight and ground-based experimentation, to update the models which predict both the environments and the environmental effects on spacecraft, and finally to ensure that this information is properly maintained and inserted into spacecraft design programs. This paper will describe the current SEE Program and will present SEE contamination engineering technology development and risk mitigation for future spacecraft design.

Pearson, Steven D.↗
NASA NTRS2003

NASA's Space Environments and Effects (SEE) Program

This viewgraph presentation gives a broad overview of NASA's Space Enivronments and Effects (SEE) Program. The purpose of the program is to protect spacecraft and their systems from damage by radiation, spacecraft charging, micrometeoroids, contamination, and other hazards posed by aerospace environments. The presentation profiles SEE activities to address each of these hazards. SEE is responsible for overseeing research and product development with a variety of partners.

Kauffman, Billy↗