Building on more than a decade of data from International Space Station (ISS) research, NASA is expanding its materials science research by flying an experiment on the U.S. Air Force X-37B space plane.

By flying the Materials Exposure and Technology Innovation in Space (METIS) investigation on the X-37B, materials scientists have the opportunity to expose almost 100 different materials samples to the space environment for more than 200 days. METIS is building on data acquired during the Materials on International Space Station Experiment (MISSE), which flew more than 4,000 samples in space from 2001 to 2013.

"By exposing materials to space and returning the samples to Earth, we gain valuable data about how the materials hold up in the environment in which they will have to operate," said Miria Finckenor, the co-investigator on the MISSE experiment and principal investigator for METIS at NASA's Marshall Space Flight Center in Huntsville, Alabama.

"Spacecraft designers can use this information to choose the best material for specific applications, such as thermal protection or antennas or any other space hardware."

The International Space Station is a unique orbiting laboratory used to conduct hundreds of investigations each year, with half of the research resources designated as a U.S. National Laboratory for investigations selected through the Center for the Advancement of Science in Space (CASIS) to provide direct benefits to people living on Earth.

NASA research focuses on advancing scientific knowledge and demonstrating technologies to enable human exploration into deep space through investigations such as the current one-year mission with NASA astronaut Scott Kelly.

It is difficult to simulate all the aspects of the space environment, so testing materials for extended durations is particularly important. Programs across the aerospace industry, including NASA's Mars Curiosity rover, the James Webb Space Telescope, and SpaceX's Dragon spacecraft have improved performance by selecting materials tested on the space station.

All of the data from the MISSE investigations are available in the Materials and Processes Technical Information System, where the METIS data also will be made available.

Researchers are flying some materials as part of METIS that also were tested during MISSE. Testing the same types of materials again can help scientists verify results obtained on the orbital outpost. If researchers see different results between the same type of materials used on both METIS and MISSE, it would help scientists learn about the differences experienced in various orbital environments.

"When we flew newly developed static-dissipative coatings on MISSE-2, we did not know they would be used for both the Curiosity rover and the SpaceX Dragon," said Finckenor. "Some program we don't know about now will be successful because engineers found the data they needed."

The METIS experiment complements the station research, looking at a variety of materials of interest for use on spacecraft built by NASA, industry, and other government agencies. The materials flown in space are potential candidates to replace obsolescent materials with environmentally-friendly options.

Finckenor leads a diverse team of investigators from other NASA centers, aerospace companies, and universities. For both MISSE and METIS, the customers supply small quarter-size samples. METIS will fly a variety of materials including polymers, composites, and coatings. Finckenor prepares the samples for flight and helps with post-flight sample analysis.

"Data from the space station and METIS materials experiments will improve the lifetime and operations of future spacecraft needed for NASA's journey to Mars," said Lisa Watson-Morgan, Marshall's chief engineer.

Marshall provided the hardware for the experiment, while the Air Force is providing NASA the opportunity to fly the experiment. The flight provides researchers an opportunity to collect additional data in advance of the next MISSE experiment aboard the space station in a couple of years.

The Air Force operates the unpiloted, robotically controlled and reusable X-37B space plane to test technology during long-duration missions. It has completed three missions launching from Cape Canaveral Air Force Station in Florida and landing at Vandenberg Air Force Base in California, with the last mission ending in October 2014 after 674 days in orbit. It takes off vertically, lands horizontally, and continues to further industrial advancement for reusable space test vehicles.

Data in the Materials and Processes Technical Information System are available to U.S. citizens, who can apply for an account here