Materials International Space Station Experiment - 6A and 6B (MISSE-6A and 6B) - 11.19.14
ISS Science for Everyone
Science Objectives for Everyone
Materials International Space Station Experiment - 6A and 6B (MISSE-6A and 6B) is a sample box attached to the outside of the International Space Station; it is used for testing the effects of exposure to the space environment on small samples of new materials. These samples will be evaluated for their reaction to atomic oxygen erosion, direct sunlight, radiation, and extremes of heat and cold. Results will provide a better understanding of the durability of various materials, with important applications in the design of future spacecraft.
Science Results for Everyone
As a child, your toy spaceship was made of cardboard, but the real things have to be a lot tougher to stand up to space. More than 400 materials took a ride in a sample box outside of the space station so researchers could see how they handled exposure to atomic oxygen, direct sunlight, radiation, and extreme heat and cold. Results suggest that materials made of protein could be bio-engineered to withstand the extremes of space. The data directs further research on the best materials for building spacecraft and satellites with improved performance and useful life.
United States Department of Defense Space Test Program, Johnson Space Center, Houston, TX, United States
Boeing, Phantom Works, Renton, WA, United States
Langley Research Center, Hampton, VA, United States
Marshall Space Flight Center, Huntsville, AL, United States
Sponsoring Space Agency
National Aeronautics and Space Administration (NASA)
National Laboratory - Department of Defense (NL-DoD)
ISS Expedition Duration
October 2007 - October 2009
Previous ISS Missions
NASA has conducted a series of space experiments to determine the best materials to survive in the space environment on Shuttle and Mir. This is a continuing investigation which began during Expedition 16 and will be returned to Earth during Expedition 19/20.
- MISSE-6A and 6B will assess impacts of the space environment (vacuum, solar radiation, atomic oxygen, micrometeorites and thermal cycling, etc.) on materials.
- Specimens include candidate spacecraft materials for long-term exposure to the space environment.
- Following return to Earth these materials will be analyzed to determine which materials could withstand the harsh environment of space and can be used in the design of future spacecraft.
The samples for MISSE-6A and 6B include over 400 new and affordable materials that may be used in advanced reusable launch systems and advanced spacecraft systems including optics, sensors, electronics, power, coatings, structural materials and protection for the next generation of spacecraft. The development of new generations of materials and material technologies is essential to the mission of traveling beyond Earth's orbit. The samples are installed in holders and placed in experiment trays, called passive experiment containers (PECs).
MISSE-6A and 6B were brought back to Earth onboard the Shuttle Discovery during the STS-128 (17A) mission in September 2009.
Results will provide a better understanding of the durability of various materials when they are exposed to the space environment. Many of the materials may have applications in the design of future spacecraft.
The new advanced materials and components that will be demonstrated in MISSE-6A and 6B will improve the performance, increase the useful life, and reduce the costs of future space operations of commercial weather, communication and Earth observation satellites that we all now depend on.
MISSE-6A and 6B is mounted to the Station's exterior on a truss segment. It requires power provided by the Station, but does not require crew interaction. The critical interaction is between the samples and the space environment.
During extravehicular activity astronauts will install the MISSE-6A and 6B on the ISS. During EVAs throughout the deployment of MISSE-6A and 6B crewmembers will capture snapshots of the PECs, if time permits. Another set of crewmembers in a later increment will retrieve MISSE-6A and 6B when the experiment is completed. The samples will be returned to the investigators, who will carefully examine each to determine how the materials fared.
The following information is a sampling of the results obtained from MISSE-6A and 6B thus far.
Collagen and silk were flown to the ISS in the Materials International Space Station Experiment-6A and 6B (MISSE-6A and 6B) and exposed to space for nearly 18 months. All protein materials were changed but to different degrees depending on the material. Around 10-15 percent surface depth of silk and collagen films was etched away by heavy ionizing particles such as atomic oxygen, the major component of the low-Earth orbit space environment. Similar surface damage was created by oxygen plasma etching exposure control experiments on Earth. Unexpectedly, laboratory analysis revealed that more than 80 percent of the silk and collagen protein chains were chemically crosslinked by penetrating space radiation, causing changes to the proteins. Silk-silica composites or triple-helix structures in native Type I collagens were more resistant to the impact of radiation in space than silk. It was also shown that resistance to high heat decreased after space travel for the protein samples. Results suggest that protein materials could be bioengineered to help protect them in the extreme space environments.
Black Kapton® XC polyimide films on MISSE-6A and 6B exhibited higher erosion rate when the films are stretched during the exposure period. Although a slight stress dependence was also observed in the ground based samples, both in appearance and in the erosion yield, it was not to the extent seen in the space-exposed samples. Differences such as atomic oxygen, levels of UV radiation, temperature, and charged particles between the ground based and space environments could have caused this difference. Coatings of silicon dioxide and silicon showed evidence of cracking while under stress. The cracking can lead to failure of the underlying polymer material if cracks are exposed to high levels of atomic oxygen. This appeared to be the cause of failure for the silicon oxide (SiOx) coated Kapton flown on the ram side of MISSE-6A and 6B. Microscopic photos of the Kapton XC samples show very little erosion on the unstressed samples, but noticeable surface texturing under slight stress, and almost complete erosion under stresses greater than the tensile yield stress.
The failure of vapor deposited aluminum (VDA) polymer films appears to be dependent on the level of environment exposure. VDA samples under stress exposed on the ram side of MISSE-6A and 6B failed while the sample exposed under stress on the wake side did not. MISSE-6A and 6B hosted samples with titanium and aluminum oxide cermet coating having the optical properties of high-solar absorptance and low infrared emittance. Spectral reflectance data obtained before and after flight revealed essentially no change in the optical properties of solar absorptance and infrared emittance upon low-Earth orbit exposure, consistent with ground laboratory evaluation of similar cermet coatings.
An atomic oxygen fluence monitor, flown as part of the MISSE-6B, was designed to measure the accumulation of atomic oxygen fluence with time as it impinged upon the ram (front) surface of MISSE-6B. This was an active experiment for which data was to be stored on a battery-powered data logger for post-flight retrieval and analysis. An atomic oxygen fluence of 1.37 ± 0.16×1021 atoms/cm2 was measured. The fluence was approximately 30 percent lower than fluences measured using Kapton® H samples from an adjoining MISSE-6A passive experiment container. Possible slippage due to launch or retrieval vibration or thermal cycling caused creep causing the gap between the pyrolytic graphite wedges to become closer together by 0.0012 cm appears to be the most likely cause of the fluence discrepancy.
Further testing is needed to isolate the factors that result in increased erosion under stress. These findings are critical for designing next-generation biocompatible materials and measurement systems for the space environments, where the effects of heavy ionizing particles and other cosmic radiation need to be considered. Further testing is needed to isolate the factors that result in increased erosion under stress.
Jaworske DA. Space durable solar selective coating cermet. Journal of Thermophysics and Heat Transfer. 2011; 25(3): 462-463.
Miller SK, Dever JA, Banks BA, Waters DL, Sechkar EA, Sechkar EA, Kline S. MISSE 6 Polymer Film Tensile Experiment. NASA Technical Memorandum; 2012 Aug.
Banks BA, Miller SK, Waters DL. Materials International Space Station Experiment-6 (MISSE-6) Atomic Oxygen Fluence Monitor Experiment. NASA Technical Memorandum; 2010 May.
Miller SK, Banks BA, Sechkar EA, Sechkar EA. An Investigation of Stress Dependent Atomic Oxygen Erosion of Black Kapton Observed on MISSE 6. NASA Technical Memorandum; 2012 Dec.
Hu X, Raja WK, An B, Tokareva O, Cebe P, Kaplan DL. Stability of silk and collagen protein materials in space. Scientific Reports. 2013 December 5; 3: 3428. DOI: 10.1038/srep03428.
Ground Based Results Publications
de Groh KK, Banks BA, Mitchell GG, Yi GT, Guo A, Ashmead CC, Roberts LM, McCarthy CE, Sechkar EA, Sechkar EA. MISSE 6 stressed polymers experiment atomic oxygen erosion data. NASA Technical Memorandum; 2013 March. [Prepared for: 12th International Symposium on Materials in the Space Environment (ISMSE-12); Noordwijk; 24-28 Sep. 2012; Netherlands]
ISS Research Project- MISSE-6A and 6B
Aggie Physicists Retrieve Package From Space
NASA Image: STS105-346-007 - Astronaut Patrick G. Forrester, during the second STS-105 extravehicular activity, prepares to work with the Materials International Space Station Experiment 1 and 2(MISSE-1 and 2). The experiment was installed on the outside of the Quest Airlock during the first extravehicular activity (EVA) of the STS-105 mission. MISSE will collect information on how different materials weather in the environment of space.
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NASA Image ISS013E63407: Image of MISSE 3 following deployment on the outside of ISS on August 3, 2006.
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Image of MISSE-5 samples prior to launch to the International Space Station for deployment during Increment 11. Image courtesy of NASA, Johnson Space Center.
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NASA Image: s123e009655 - Close-up view of Materials International Space Station Experiment-6A and 6B (MISSE-6A and 6B) Passive Experiment Container on European Laboratory/Columbus. Photo was taken during flyaround of STS-123 Space Shuttle Endeavor.
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NASA Image: ISS020E037369 (Sept. 2009) --- A close-up view of a Materials International Space Station Experiment (MISSE-6) on the exterior of the Columbus laboratory is featured in this image the STS-128 mission’s first session of extravehicular activity (EVA).
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