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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 NTRS1992

Thermal Control Surfaces Experiment (TCSE) materials analysis

Materials on the Thermal Control Surfaces Experiment (TCSE) underwent changes in their properties during the 5.8 years of exposure to the combined space environment. The analysis of these materials is continuing and current results are discussed. Some materials were significantly degraded such as silver Teflon, S13GLO, and Z302; while others such as Z93 and YB71 were stable. Time dependent flight data is provided, along with preflight and postflight measurements. Results are compared with other experiments, demonstrating the atomic oxygen (AO) ram effect. Atomic oxygen texturing of silver Teflon varies with incident angle. Even indirect exposure to atomic oxygen appears to be involved with surface texturing on the interior of the TCSE. Localized contamination occurred at discrete locations both inside and on exterior surfaces. Most of the visible deposits were the result of the classical photo-enhanced contamination deposition. The synergism of combined space environmental effects is demonstrated by the specific localization of contamination caused by photo-enhanced deposition versus AO removal. Optical degradation measurements of these contaminated areas, utilizing a new portable reflectometer, are presented.

Wilkes, Donald R.↗
NASA NTRS1990

Past experience Skylab mission

The design of the Skylab missions, 1973 to 1974, was intended to exclude any direct handling of hazardous, toxic, or reactive materials. The materials processing facility and multipurpose furnace provided a contained environment for conducting metals melting, brazing, sphere forming, and crystal growth experiments. At the end of the third mission, following the completion of all other experiments, the materials processing facility was used for a series of flammability experiments. The flammability tests were done last because of the contamination expected from the burning of the materials within the facility. The flammability tests demonstrated a number of peculiar effects that have implications for future design (fire detection, location, and suppression/control). Although the results of the flammability tests contain lessons appropriate to planning, a number of events during the flight illustrate situations or conditions that pose considerations beyond the commonly accepted range of concern for safety-related matters. This presentation includes a discussion of: Skylab flammability studies and the implications for fire suppression/control; false fire alarms and the Skylab fire detection system; space environmental effects on materials that are normally benign; spills/release of contaminants; the detrimental effect that the release of non-hazardous materials have on detection systems; and the problem of locating sources/originating point of hazards.

Pogue, William↗
NASA NTRS1996

X-Ray Imaging Study

The space environment in which the Space Station Freedom and other space platforms will orbit is truly a hostile environment. For example, the currently estimated integral fluence for electrons above 1 Mev at 2000 nautical miles is above 2 x 1O(exp 10) electrons/sq cm/day and the proton integral fluence is above 1 x 10(exp 9) protons/sq cm/day. At the 200 - 400 nautical miles, which is more representative of the altitude which will provide the environment for the Space Station, each of these fluences will be proportionally less; however, the data indicates that the radiation environment will obviously have an effect on structural materials exposed to the environment for long durations. The effects of this combined environment is the issue which needs to be understood for the long term exposure of structures in space. At the same time, there will be substantial potential for collisions between the space platforms and space debris. The current NASA catalogue contains over 4500 objects floating in space which are not considered payloads. This debris can have significant effects on collision with orbiting spacecraft. In order to better understand the effect of these hostile phenomena on spacecraft, several types of studies are being performed to simulate at some level the effect of the environment. In particular the study of debris clouds produced by hypervelocity impact on the various surfaces anticipated on the Space Station is very important at this point in time. The need to assess the threat of such debris clouds on space structures is an on-going activity. The Space Debris Impact facility in Building 4612 provides a test facility to monitor the types of damage produced with hypervelocity impact. These facilities are used to simulate space environmental effects from energetic particles. Flash radiography or x-ray imaging has traditionally provided such information and as such has been an important tool for recording damage in situ with the event. The proper operation of the system can provide much useful information with respect to parametric analysis of the hypervelocity experiment. The following report outlines the procedures developed to optimize the operation of the x-ray imaging system and its operational characteristics.

OBrien, Susan K.↗
NASA NTRS1992

The possible effects of the natural and induced space environment on the optical and thermal properties of EOS surfaces

Space missions, including that of EOS (Earth Observing System), will continue to be subjected to both the natural and induced space environment. The concerns associated with this fact will not go away. The NASA and DoD have recognized the need for long-life stability of materials and structures to the space environment. The major areas of interest include: thermal cycling, UV degradation, space radiation exposure, orbital debris, atomic oxygen erosion, and contamination control. Having flown a number of space environmental effects monitors, SAIC has developed both a data base to understand the magnitude of this problem and mitigation techniques to reduce the impact.

Maag, Carl R.↗
NASA NTRSDate not supplied

Update on Planetary, Lunar, & Asteroid Natural Environment Testbed (PLANET)

At ISMSE15, the Planetary, Lunar, & Asteroid Natural Environment Testbed (PLANET) was introduced as an upcoming high-fidelity, combined-effects planetary surface environment laboratory. This year, we will present an update on the facility status, describing the procurement, installation, commissioning of the chamber in Huntsville, Alabama (USA). With NASA’s push to return to the Moon through the Artemis program, there is a clear need for more high-fidelity test chambers that can replicate multiple aspects of the lunar surface, especially the fine, dusty lunar soil known as regolith. The PLANET chamber is designed to fill this gap, enabling research & development, qualification, and verification testing in a combined lunar surface environment, at an affordable price, for government, commercial/industry, and academic partners. Features include a large regolith simulant bed, low energy electron and ion sources to replicate the solar wind, full-spectrum UV and Solar simulation, and a liquid nitrogen cryogenic shroud, all in a high-vacuum environment (as low as 10^-7 mbar). PLANET’s initial focus will be on the lunar environment, but other surface environments (Martian, asteroid, etc.) are also possible to simulate. Besides the environmental instrumentation, PLANET will be equipped with specialized test systems that the Space Environmental Effects Team has developed over the past two years, including an in-situ tribometer and uniform dust distribution system. The chamber is currently being manufactured, with plans to install in May 2024. This will be followed by outfitting and commissioning. The challenges and accomplishments seen during this process will be detailed, and data from the first tests performed in PLANET will be shared with the community.

environmental testing↗
NASA NTRS1993

Surface characterization of LDEF materials

The NASA Long Duration Exposure Facility (LDEF), a passive experimental satellite, was placed into low-Earth orbit by the Shuttle Challenger in Apr. 1984. The LDEF spent an unprecedented 69 months in space. The flight and recovery of the LDEF provided a wealth of information on the longterm space environmental effects of a variety of materials exposed to the low-Earth orbit environment. Surface characterization of LDEF materials included polymers, composites, thermal control paints, and aluminum. X-ray photoelectron spectroscopy (XPS), Auger electron spectroscopy (AES), scanning electron microscopy (SEM), and contact angle analysis were used to document changes in both the surface composition and surface chemistry of these materials. Detailed XPS analysis of the polymer systems, such as Kapton, polyimide polysiloxane copolymers, and fluorinated ethylene propylene thermal blankets on the backside of the LDEF revealed significant changes in both the surface composition and surface chemistry as a result of exposure to the low-Earth orbit environment. Polymer systems such as Kapton, polyimide polysiloxane copolymers, and polysulfone showed a common trend of decreasing carbon content and increasing oxygen content with respect to the control sample. Carbon 1s curve fit XPS analysis of the composite samples, in conjunction with SEM photomicrographs, revealed significant ablation of the polymer matrix resin to expose the carbon fibers of the composite during exposure to the space environment. Surface characterization of anodized aluminum tray clamps, which were located at regular intervals over the entire LDEF frame, provided the first results to evaluate the extent of contamination with respect to position on the LDEF. The XPS results clearly showed that the amount and state of both silicon and fluorine contamination were directly dependent upon the position of the tray clamp on the LDEF.

Wightman, J. P.↗
NASA NTRS2004

Status of Solar Sail Material Characterization at NASA's Marshall Space Flight Center

Near term solar sail propelled science missions are targeting the Lagrange point 1 (Ll) as well as locations sunward of L1 as destinations. These near term missions include the Solar Polar Imager' and the L1 Diamond '. The Environmental Effects Group at NASA's Marshall Space Flight Center (MSFC) continues to actively characterize solar sail material in preparation for these near term solar sail missions. Previous investigations indicated that space environmental effects on sail material thermo-optical properties were minimal and would not significantly affect the propulsion efficiency of the sail. These investigations also indicated that the sail material mechanical stability degrades with increasing radiation exposure. This paper will further quantify the effect of space environmental exposure on the mechanical properties of candidate sail materials. Candidate sail materials for these missions include Aluminum coated Mylar(TradeMark), Teonex(TraeMark), and CP1 (Colorless Polyimide). Experimental data will be presented on sail material response to charged particle radiation and subsequent Hypervelocity Impact (HVI). Data will also be presented indicating mechanical property variations in sail material resulting from electron exposure, proton exposure, and a combined electron and proton exposure. Tabular data consisting of areal density, thickness, thermo-optical, mechanical, and electrical properties, vacuum stability and outgassing will be presented.

Edwards, David L.↗
NASA NTRS1972

Recent advances in spacecraft thermal-control materials research.

The state-of-the-art of spacecraft thermal-control materials technology has been significantly advanced during the past 4 years. Selective black coatings are discussed together with black paints, dielectric films on metal surfaces, and white radiator coatings. Criteria for the selection of thermal-control surfaces are considered, giving attention to prelaunch protection, the capability of being measured, reproducibility, simulator response, and aspects of a nonindigenous space environment. Progress in space simulation is related to vacuum technology, ultraviolet sources, solar wind simulation, and the production of protons. Advances have been made in the protection against space environmental effects, and in the development of thermal-control surfaces and pigments.

Zerlaut, G. A.↗
NASA NTRS1982

The LDEF benefits

The Long Duration Exposure Facility (LDEF) is described, and experiments planned for the first LDEF mission are discussed. Four of the eight involve scientific studies of interstellar gas, micrometeoroids, cosmic rays, and crystal growth in zero gravity, and four involve technology studies of the space environmental effects on solar cells, composite materials, thermal coatings, fiber optics, and electronic instruments. For each experiment, the objectives and methods are discussed.

Kinard, W. H.↗
NASA NTRS1984

Radiation damage and annealing of amorphous silicon solar cells

Amorphous silicon solar cells were irradiated with 1 MeV electrons at the Space Environmental Effects Laboratory of the NASA Langley Research Center. The cells accumulated a total fluence of 10 to the 14th, 10 to the 15th, and 10 to the 16th electrons per square centimeter and exhibited increasing degradation with each irradiation. This degradation was tracked by evaluating the I-V curves for AM0 illumination and the relative spectral response. The observed radiation damage was reversed following an anneal of the cells under vacuum at 200 C for 2 hours.

Byvik, C. E.↗
NASA NTRS1988

Materials and structures

Information on materials and structures for use in space is given in viewgraph form. Information is given on the Materials and Structures Division of NASA's Office of Aeronautics and Space Technology. The Division's space research and development budget is given. Further information is given on space materials and structures, space environmental effects, radiation effects, high temperature materials research, metal matrix composites, SiC fiber reinforced titanium alloys, structural dynamics, and control of flexible structures.

Venneri, Samuel L.↗
NASA NTRS1990

Technologies for global change earth observations

Advances in the areas of space-based observations, data/information analysis, and spacecraft/operations for the studying of global changes are discussed. Research involving systems analysis, observation technologies, information technologies, and spacecraft technologies is examined. Consideration is given to cryogenic coolers, IR arrays, laser and submillimeter sensing, large array CCD, information visualization, design knowledge capture, optical communications, multiinstrument pointing, propulsion, space environmental effects, and platform thermal systems.

Johnston, Gordon I.↗
NASA NTRS1991

An overview of the first results on the solar array passive LDEF experiment (sample), AO171

Space environmental effects were visibly obvious on components of experiment AO171 which contained solar cells, composites, polymeric thin films, solar reflectors, protective coatings, metals, paints , and elastomers. Micrometeoroid/space debris impacts were observed on all experiment elements. Luminescence of polyimide, silicone, and polyurethane materials occurred under black light examination. Outgassing of RTV511 occurred mainly as a result of insufficient thermal vacuum bakeout. Solar cell degradation was predominantly below 10 percent. Elastomers lost mass and discolored; composites showed evidence of atomic oxygen attack, and unprotected thin polymer films eroded away.

Whitaker, Ann F.↗
NASA NTRS1991

Passive exposure of Earth radiation budget experiment components LDEF experiment AO-147: Post-flight examinations and tests

The Passive Exposure of Earth Radiation Budget Experiment Components (PEERBEC) experiment of the Long Duration Exposure Facility (LDEF) mission was composed of sensors and components associated with the measurement of the earth radiation budget (ERB) from satellites. These components included the flight spare sensors from the ERB experiment which operated on Nimbus 6 and 7 satellites. The experiment components and materials as well as the pertinent background and ancillary information necessary for the understanding of the intended mission and the results are described. The extent and timing of the LDEF mission brought the exposure from solar minimum between cycles 21 and 22 through the solar maximum of cycle 22. The orbital decay, coupled with the events of solar maximum, caused the LDEF to be exposed to a broader range of space environmental effects than were anticipated. The mission spanned almost six years concurrent with the 12 year (to date) Nimbus 7 operations. Preliminary information is presented on the following: (1) the changes in transmittance experienced by the interference filters; (2) the results of retesting of the thermopile sensors, which appear to be relatively unaffected by the exposure; and (3) the results of the recalibration of the APEX cavity radiometer. The degradation and recovery of the filters of the Nimbus 7 ERB are also discussed relative to the apparent atomic oxygen cleaning which also applies to the LDEF.

Hickey, John R.↗
NASA NTRS1991

Space Photovoltaic Research and Technology Conference

The Eleventh Space Photovoltaic Research and Technology conference was held at NASA Lewis Research Center from May 7 to 9, 1991. The papers and workshop summaries presented here report remarkable progress on a wide variety of approaches in space photovoltaics, both near and far term applications. Papers were presented in a variety of technical areas, including multijunction cell technology, GaAs and InP cells, system studies, cell and array development, and photovoltaics for conversion of laser radiation. Three workshops were held to discuss thin film cell development, III-V cell development, and space environmental effects.

Source record↗
NASA NTRS1992

Selected results for LDEF thermal control coatings

The investigation of space environmental effects on LDEF thermal control coatings by the Materials Special Investigation Group is continuing. Analyses of chromic acid anodize, A276 white paint, and Z306 black paint were conducted, assessing performance as functions of environmental exposure. Test results from additional coatings, such as on scuff plates, M003, and the black chromium plate solar absorber, were obtained. Guidelines for the use of these materials and comparisons to ground based test data will be presented.

Golden, Johnny L.↗