500 Samples Exposed To Solar Radiation, Other Factors

Air Force Research Laboratory officials here recently partnered with NASA to conduct materials experiments aboard the International Space Station. The project incorporates 500 materials samples into two suitcase-like containers attached to the exterior of the orbital platform.

The containers are fully opened and folded back to expose them to atomic oxygen bombardment, solar radiation, extreme temperature changes, and other severe space environmental factors. They will remain in that configuration until retrieved by International Space Station astronauts and brought back to Earth aboard a space shuttle.

Members of the Laboratory's Materials and Manufacturing and Propulsion directorates, working with NASA, the US Air Force Academy, Sandia National Laboratories, US Naval Research Laboratory, Air Force Office of Scientific Research, Boeing, the Space Test Program, Aerospace Corp., deployed the sixth in a series of materials experiments to the International Space Station via a space shuttle.

The International Space Station provides a tremendous opportunity to demonstrate and qualify promising new materials that may offer weight, performance and cost savings benefits, and to re-qualify existing materials, said Shane Juhl, an engineer at AFRL and current program manager for the Materials on the International Space Station Experiment program, known as MISSE.

"Due to the limited number of qualified materials for space, manufacturers tend to build spacecraft using existing qualified materials," Mr. Juhl said. "MISSE offers a cost-effective means for testing new materials and requalifying existing ones whose suppliers or processing methods have undergone change over time.

"No single piece of equipment or facility currently exists that can simultaneously expose materials to all the damaging environmental effects of space," Juhl said. "In the laboratory, samples can be exposed to only a limited number of simulated environments at a time. In space -- the ultimate testing environment -- samples are exposed to all the harsh realities of the space environment at once."

Until now, the AFRL Materials and Manufacturing Directorate staff has deployed only passive experiments to the International Space Station (experiments characterized before and after deployment). The ongoing mission, MISSE 6, incorporates eight active AFRL experiments that collect and store data in real time continuously or at set intervals for later analysis.

"The transition to more active experimentation will provide unprecedented information about the on-orbit effects on material properties of interest and will help reduce material screening and qualification costs," Juhl said. "This will free up more funding for mission-critical programs."

MISSE 6 is comprised of two containers and incorporates 40 samples from AFRL including the eight active experiments. Officials say a seventh deployment is in the planning phase.

FMI: www.nasa.gov, www.af.mil