As humankind’s forays into space become simultaneously more commonplace and ambitious, the need for a fundamental understanding of the interactions between the harsh space environment and spacecraft materials becomes ever more important. Further, as the requirements for new space missions become more stringent and extensive, novel lightweight materials must be developed with improved long-term radiation shielding and mechanical properties for use in internal and external spacecraft systems. Novel materials born on the expanding boundaries of organic polymer chemistry, which offer better elasticity, mechanical strength, and corrosion resistance, could result in improved spacecraft design and mission duration. However, before implementation, they must be thoroughly tested to predict their performance over the entire mission lifetime.

Low Earth Orbit  is a particularly harsh environment for spacecraft materials because atomic oxygen is present along with all other environmental components such as unfiltered solar UV radiation and high-energy radiation from different sources (solar particle events, radiation flux from the South Atlantic Anomaly and galactic cosmic ray background). Team of researchers lead by Dr. Elena Plis, a Senior Research Engineer at Electro-Optical Systems Laboratory/GTRI, will utilize the International Space Station  U.S. National Laboratory for investigation of short- and long-term degradation effects of LEO on selected materials which show promise for aerospace, avionics, and spacecraft applications, including liquid crystal polymer, polyhedral oligomeric silsesquioxane (POSSÒ), carbon fiber reinforced polymers, polyimides, and polyethylene teraphthelate  polyester films. The project called “Spectral Characterization of Novel Spacecraft Materials at LEO Environment” began on August 31.

Researchers will measure time-resolved environmentally-induced optical changes of materials mounted on the ram, zenith, and wake faces of the Materials International Space Station Experiment (MISSE) Flight Facility, an in-orbit platform from Alpha Space Test and Research Alliance deployed externally onboard the ISS.  By correlating spectral reflectivity (color) changes that occur as a result of exposure to different components of the LEO to a host of other material properties determined using ground-based characterization, the research team will enable Earth-bound observers to glean knowledge about a spacecraft by examining the spectral signature of unresolved images. Use of spacecraft optical properties in this way will increase space domain awareness and enable remote diagnosis and anomaly resolution. Lastly, laboratory-based irradiation experiments are nearly always performed at an accelerated dose rate with imperfect radiation sources. Therefore, truth data gathered in the actual space weather environment are invaluable for developing accurate ground testing protocols.  

The multi-organizational research team includes Drs. Daniel Engelhart, Vanessa Murray, and Ryan Hoffmann from the Space Vehicles Directorate of the Air Force Research Laboratory at Kirtland Air Force Base, Dr. Gregory Badura from Electro-Optical Systems Innovation Division at Electro-Optical Systems Laboratory (EOSID/EOSL)/GTRI, Dr. Heather Cowardin from NASA, Drs. Darren Cone and David Roberson from University of Texas at El Paso. Mr. Timothy Scott will be the team’s liaison with DuPont de Nemours, Inc.

- Elena Plis | Senior Research Engineer, GTRI Electro-Optical Sys Labs