Materials International Space Station Experiment Research Articles

Ground Testing of the 16th Materials International Space Station Experiment Materials

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 correlation factors between true space exposure and accelerated space weather experiments at ground facilities enables accurate prediction of on-orbit material performance based on laboratory-based testing. The presented work aims to evaluate the radiation effects of a low-Earth-orbit environment, namely, exposure to the high-energy electrons and atomic oxygen (AO) of heritage and novel spacecraft material selection. The studied materials represent the “flight duplicates” of samples that are launched as a part of the 16th Materials International Space Station Experiment Flight Facility (MISSE-FF) mission in 2022.

Multi-faceted simulation of atomic oxygen erosion of deorbit sail for cleaning space debris

Deorbit sails are used in low earth orbit to reduce the growing amount of orbital debris by rapidly removing satellites at the end of their operational missions. However, in low earth orbit, atomic oxygen (AO) is a potential threat to long-duration exposure facilities. In this work, a multi-faceted simulation for the AO erosion of the Taurus Deorbit Sail was developed to calculate the erosion yield for the membrane material and the undercutting profile at the crease site. The disintegration and erosion detail for the deorbit sail membrane during AO impacts can be studied on an atomic scale. The ReaxFF reaction force field program is used to provide a large enough calculation speed in the size of the system to describe all the chemical reactions of the reaction. The on-orbit flight data from the Materials International Space Station Experiment 2 were used to validate the simulated erosion rate in this study. The defects on the deorbit sails were experimentally measured using a scanning electron microscope and then modeled by the Monte Carlo method. The computational predictions of AO undercutting at the defect sites were validated by experimental data from the NASA long-duration exposure facility. The disintegration of the membrane could be divided into two stages: the physical reaction stage and the chemical reaction stage, after 150 AO collisions the membrane becomes highly volatilized. The maximum undercutting depth for the deorbit drag sail within the predicted 37-month deorbit time was 5.5 μm and 7.5 μm for a defect width of 500 nm and 1 μm, respectively. The undercutting width for a deorbit sail with a width of 500 nm or 1 μm was predicted to be 1.6 μm and 2 μm, respectively, and the breaker was formed at the bottom of the undercutting profile. AO erosion has been studied by researchers in terms of evaluating the effectiveness of protective coatings. This current study, however, seeks to understand the fundamental interactions between AO and creases in the deorbit sail, which provides deeper knowledge than what has been developed so far. The multi-faceted simulation results can provide design references for engineering applications for the deorbit sail.

Space survivability for printed electronics applications

The effects of atomic oxygen (AO) in low earth orbit and the physical effects of space launch on printed materials were studied for aerosol-jet printed Au and Ag through a 6 month exposure period on the Materials International Space Station Experiment (MISSE). RF and DC test platforms were designed for two printed electronics-compatible substrates (Rogers CLTE-XT and Ferro L8) to assess the amount of degradation caused by AO exposure in space. A passivation layer of CORIN-XLS applied over the printed metal traces was also studied for its effectiveness. Both bare and passivated test structures of printed Ag and Au traces were exposed to low earth orbit on the 10th MISSE mission. The effects of AO and the 6 month space exposure on the samples are reported here.

Effect of 1.5 Years of Space Exposure on Tensile Properties of Teflon

Materials on the exterior of spacecraft in low Earth orbit are subject to extremely harsh environmental conditions, including exposure to various forms of radiation, temperature extremes, thermal cycling, and atomic oxygen. These environmental exposures can result in erosion and optical and mechanical property degradation of susceptible materials, threatening spacecraft performance and durability. In an effort to better understand the effect of space exposure on the mechanical property degradation of Teflon insulation, 19 tensile samples were exposed to the space environment for 1.5 years on the exterior of the International Space Station. The samples were flown in ram, wake, zenith, or nadir orientations as part of three Materials International Space Station Experiment 7 mission experiments. This paper provides an overview of the flight mission, an introduction to the experiments, and compares the Teflon property degradation in the various orientations. The reduction in ductility of the samples correlates with the amount of solar radiation. Samples with high solar exposure (zenith orientation) experienced a 76% reduction in elongation relative to controls, whereas samples in the shadowed nadir orientation only experienced a 4% reduction. Additionally, thickness loss measurements show that erosion is significant in the ram orientation, but negligible in other orientations.

Space survivability of carbon nanotube yarn material in low Earth orbit

Unshielded carbon nanotube (CNT) yarns were exposed in Low Earth Orbit (LEO) for 2.14 years on the exterior of the International Space Station (ISS) as part of a Materials International Space Station Experiment (MISSE-8), Payload and Optical Reflector Materials Experiment III. This work is the first to expose any commercial, continuous CNT material in a high-fluence atomic oxygen (AO) natural space environment with sample recovery. Although some chemical changes and surface roughening were observed in both the ram- and wake-exposed samples, none of the CNT yarn samples were catastrophically damaged. Yarn erosion was greater in the ram direction. Scanning electron microscopy (SEM) images showed a porous morphology that was mostly confined to the outer 1% of the yarn. This was consistent with the high degree of disorder observed in the Raman spectra. SEM micrographs also revealed that under the outer amorphous layer of oxidized carbon were pristine carbon nanotubes that were not attacked by the AO. The mechanical (tensile) data showed fairly good strength retention of the yarns exposed in the wake direction, while ram exposure resulted in a 25% strength decrease. Electrical resistivity measurements revealed that both the wake and ram samples were slightly more resistive than the control samples.

Stability of Silk and Collagen Protein Materials in Space

Collagen and silk materials, in neat forms and as silica composites, were flown for 18 months on the International Space Station [Materials International Space Station Experiment (MISSE)-6] to assess the impact of space radiation on structure and function. As natural biomaterials, the impact of the space environment on films of these proteins was investigated to understand fundamental changes in structure and function related to the future utility in materials and medicine in space environments. About 15% of the film surfaces were etched by heavy ionizing particles such as atomic oxygen, the major component of the low-Earth orbit space environment. Unexpectedly, more than 80% of the silk and collagen materials were chemically crosslinked by space radiation. These findings are critical for designing next-generation biocompatible materials for contact with living systems in space environments, where the effects of heavy ionizing particles and other cosmic radiation need to be considered.

Effect of low-earth orbit space on radiation-induced absorption in rare-earth-doped optical fibers

The implementation of optical systems, based on rare-earth doped fibers, in space environments adds a powerful new dimension of functionality to the design of space-based systems, particularly when high power and bandwidth, high fidelity, and low susceptibility to electromagnetic interference are desired. As these specialty fibers are often the most sensitive components of an optical system, extensive use requires considerable insight into the ionizing-radiation-induced changes experienced by the fibers during their operational lifetime. In this research, a suite of aluminosilicate fibers singly or co-doped with erbium and ytterbium ions was deployed into low-Earth orbit for approximately 18months as part of the Materials International Space Station Experiment (MISSE) 7 mission. Optical spectroscopy performed on the retrieved fibers is compared to control data from pristine, unirradiated fibers, revealing colorcenter generation in the visible portion of the spectrum consistent with silica-related and aluminum-related absorption centers, with band-tailing into the near-infrared. Results suggest that visible to near infra-red (NIR) absorption experienced by the co-doped fiber is less-pronounced than in its singly-doped counterparts, likely a result of the lower aluminum concentration of this fiber. The data were also compared to data from terrestrial 60Co irradiation of the same fiber types and it was found that the overall trends observed in the space-irradiated fibers in the near-infrared were accurately, although not identically, reproduced. The resultant information is important for the design and testing of radiation-hardened optical-fiber-based laser and amplifier systems.

Electrodynamic Dust Shields on the International Space Station: Exposure to the space environment

Abstract Electrodynamic Dust Shields (EDS) have been in development at NASA as a dust mitigation method for lunar and Martian missions. An active dust mitigation strategy, such as that provided by the EDS, that can remove dust from surfaces, is of crucial importance to the planetary exploration program. We report on the development of a flight experiment to fully expose four EDS panels to the space environment. This flight experiment is part of the Materials International Space Station experiment X (MISSE-X), an external platform on the International Space Station that will expose materials to the space environment.

Charge-Enhanced Contamination and Environmental Degradation of MISSE-6 SUSpECS Materials

The effects of prolonged exposure to the low Earth orbit space environment and charge-enhanced contamination on optical, thermal, and electron emission and transport properties of common spacecraft materials have been investigated by comparing pre- and postflight characterization measurements. The State of Utah Space Environment and Contamination Study (SUSpECS), deployed in March 2008 on board the Materials International Space Station Experiment (MISSE-6) payload, was exposed for ~18 months on the exterior of the International Space Station (ISS) and was retrieved in September 2009. A total of 165 samples was mounted on three separate SUSpECS panels on the ram and wake sides on the ISS. Some samples, particularly those exposed to atomic oxygen in the ram direction, showed pronounced effects due to exposure. Biased samples for the charge-enhanced contamination study showed subtle variations in visible and infrared reflectivity.

Materials International Space Station Experiment 5 Polymer Film Thermal Control Experiment

It is known that polymer films can degrade as a result of space environmental exposure, but the magnitude of the mechanical property degradation and the degree to which the different environmental factors play a role is not well understood. An experiment was flown on the Materials International Space Station Experiment 5 to determine the change in tensile strength and percent elongation of some typical polymer films exposed in a nadir-facing environment on the International Space Station and, where possible, compare with similar ramand wake-facing experiments flown on theMaterials International Space Station Experiment 1 to get a better indication of the role the different environments play in mechanical property change. It was found that the majority of the polymers tested experienced some loss in tensile/yield strength and percent elongation with polytetrafluroethylene Teflon having the greatest change.Where comparisons could be made with theMaterials International Space Station Experiment 1, it appears that the loss in percent elongation is dependent on the radiation level while the loss in tensile strength is not as sensitive to the level of radiation.

Overview of the Natural Space Environment and ESA, JAXA, and NASA Materials Flight Experiments

AbstractSpace environmental effects on materials are very severe and complex because of the synergistic interaction of orbital environments such as high-energy radiation particles, atomic oxygen, micrometeoroids, orbital debris, and ultraviolet irradiation interacting synergistically, along with thermal exposure. In addition, surface degradation associated with contamination can negatively impact optics performance. Materials flight experiments are critical to understanding the engineering performance of materials exposed to specific space environments. Likewise, the spacecraft designer must have an understanding of the specific environment in which a spacecraft will operate, enabling appropriate selection of materials to maximize engineering performance, increase mission lifetimes, and reduce risk. This article will present a methodology for assessing the engineering performance of materials baselined for a specific spacecraft or mission. In addition, an overview of the space environment, from low Earth orbit to interplanetary space, will be provided along with an overview on the effects of the space environment on materials performance. The majority of this article is devoted to materials flight experiments from the European Space Agency (ESA), the Japan Aerospace Exploration Agency (JAXA), and from the National Aeronautics and Space Administration (NASA). Some of the experiments reviewed include ESA's Materials Exposure and Degradation Experiment on the International Space Station (ISS), JAXA's Micro-Particles Capturer and Space Environment Exposure Device experiments on the ISS Service Module and on the ISS Japanese Experiment Module Exposed Facility, and NASA's Long Duration Exposure Facility satellite and the Materials International Space Station Experiment series flown on the exterior of ISS.

Space Environment Exposure of Polymer Films on the Materials International Space Station Experiment: Results from MISSE 1 and MISSE 2

A total of thirty-one samples were included in the National Aeronautics and Space Administration (NASA) Glenn Research Center (GRC) Polymer Film Thermal Control (PFTC) and Gossamer Materials experiments, which were exposed to the low Earth orbit environment for nearly 4 years on the exterior of the International Space Station (ISS) as part of the Materials International Space Station Experiment (MISSE 1 and MISSE 2). This paper describes objectives, materials, and characterizations for the MISSE 1 and MISSE 2 GRC PFTC and Gossamer Materials samples. Samples included films of polyimides, fluorinated polyimides, and Teflon® fluorinated ethylene propylene (FEP) with and without second-surface metalized layers and/or surface coatings. Films of polyphenylene benzobisoxazole (PBO) and a polyarylene ether benzimidazole (TOR-LM TM) were also included. Polymer film samples were examined post-flight for changes in mechanical and optical properties. The environment in which the samples were located was characterized through analysis of sapphire contamination witness samples and samples dedicated to atomic oxygen (AO) erosion measurements. Results of the analyses of the PFTC and Gossamer Materials experiments are discussed.

MISSE 2 PEACE Polymers Atomic Oxygen Erosion Experiment on the International Space Station

Forty-one different polymer samples, collectively called the Polymer Erosion and Contamination Experiment (PEACE) Polymers, were exposed to the low Earth orbit (LEO) environment on the exterior of the International Space Station (ISS) for nearly 4 years as part of Materials International Space Station Experiment 2 (MISSE 2). The objective of the PEACE Polymers experiment was to determine the atomic oxygen erosion yield of a wide variety of polymeric materials after long-term exposure to the space environment. The polymers range from those commonly used for spacecraft applications, such as Teflon ® FEP, to more recently developed polymers, such as high temperature polyimide PMR (polymerization of monomer reactants). Additional polymers were included to explore erosion yield dependence upon chemical composition. The MISSE PEACE Polymers experiment was flown in MISSE Passive Experiment Carrier 2 (PEC 2), tray 1, attached to the exterior of the ISS Quest Airlock. It was exposed to atomic oxygen along with solar and charged particle radiation. MISSE 2 was successfully retrieved during a space walk on July 30, 2005 during Discovery's STS-114 Return to Flight mission. Details on the specific polymers flown, flight sample fabrication, pre-flight and post-flight characterization techniques, and atomic oxygen fluence calculations are discussed along with a summary of the atomic oxygen erosion yield results. The MISSE 2 PEACE Polymers experiment is unique because it has the widest variety of polymers flown in LEO for a long duration and was exposed to an unusually clean LEO spacecraft environment. This experiment provides extremely valuable erosion yield data for spacecraft design purposes.

On-orbit and ground testing of space environment interactions with materials

During the past 12 years, a significant number of different materials have been returned to Earth after extended exposure to space in low Earth orbits. The process steps required to conduct on-orbit exposure experiments and a brief historical outline of materials experiments to date will be described. Examples of material degradation, with emphasis on coatings, will be presented using on-orbit and post-flight photographs of spacecraft hardware and flight test specimens. Results of post-flight testing will be compared with test results from ground-based systems. Oxidation of coatings, darkening of surfaces due to UV-induced chemical bond rearrangement, and displacement of oxygen atoms from pigments due to proton and electron impact, mechanical failure due to thermal cycling, damage due to microscopic particle impact, and multiple bond ruptures due to high-energy charged particles are observed on hardware returned from orbit. A current materials flight experiment that includes a significant number of coating specimens, along with many other materials, is the Materials International Space Station Experiment (MISSE). MISSE is flying today on-board the International Space Station (ISS) and will be discussed as an example of the current infrastructure available for on-orbit testing.