AF experiments to return home with Discovery

  • Published
  • By Larine Barr
  • Air Force Research Laboratory Public Affairs
WRIGHT-PATTERSON AIR FORCE BASE, Ohio (AFPN) --  After existing nearly four years on the International Space Station, more than 800 Air Force experiments will finally return home with the Space Shuttle Discovery on Aug. 7.

The space shuttle launched July 26 from Cape Canaveral, Fla., on a 12-day mission to test new flight safety procedures and deliver supplies to the station.

The Materials on the International Space Station Experiment was installed by the Space Shuttle Discovery crew in August 2001 for what was to be a one-year science experiment to learn how different materials react when exposed to the rigors of space, said Michael Stropki. He is a scientist with the Air Force Research Laboratory’s materials and manufacturing directorate here where the experiments originated.

When the shuttle Columbia exploded on re-entry Feb. 1, 2003, the experiments were forced to wait for a return to Earth aboard the recent Discovery mission.

“While the experiments were originally planned to spend only one year in space, having existed four years there may have eroded away the entire material in a few of the specimens,” said Mr. Stropki, who was the initial program manager on the project in 2001.

“In those cases, it will not be possible to know just how soon it took to reach failure,” he said. “While at the same time, for other more successful candidates, the additional time in space will likely show that those materials have a greater durability and are able to survive the space environment for the longer periods needed for these materials.”

The goal of the experiment is to discover how materials are affected by exposure in an effort to develop more durable, reliable and affordable materials and technologies for future space vehicles.

“This information is crucial to providing the needed space materials for the 21st century,” said Pat Valentino, AFRL’s current program manager. “New, affordable materials are the enablers for advanced reusable launch systems and advanced spacecraft systems, including optics, sensors, electronics, power, coatings, structural materials and protection.”

While at home on the orbiting space laboratory, the experiments have been housed in four passive experiment carriers, similar to suitcases, which NASA astronauts placed at strategic locations on the outside of the ISS. Some of the specimens include optical materials and coatings, lightweight radiation shielding materials, thermal control coatings (flight paint), Kevlar and carbon foams, multilayer insulation materials, solar cell technology and specialty materials such as shape-memory foil and X-ray resistant coatings.

At the direction of AFRL scientists, NASA integrators placed most of the specimens in aluminum trays that hold roughly 46 samples. Other specimens were installed directly onto the trays, while a few specimens were bolted underneath the base plates to ensure they were exposed only to solar radiation.

Besides Air Force experiments, the experiment payload carries 11 handpicked experiments from six Dayton, Ohio, area students in first through 10th grades.

“Their assignment was to identify a problem associated with long duration flight, propose a solution and design a passive experiment to find a solution,” Mr. Stropki said.

Included are experiments to learn how contamination migrates in a microgravity environment, how materials degrade, radiation shielding tests and the effect of space on viral protein and nonpathogenic bacteria.

All the specimens have faced such grueling perils as ultraviolet ray bombardment by highly corrosive atomic oxygen, and exposure to intense solar radiation during maximum solar activity, Ms. Valentino said.

On Flight Day 9 of the Discovery mission, astronauts will uninstall the experiment containers from the exterior of the space station and return to Earth about three weeks after launch. From there, the materials will travel to NASA Langley Research Center in Virginia where scientists will de-integrate and disassemble the containers, then ship them back to AFRL scientists to be analyzed.

“We are incredibly excited that (the experiments are) finally returning home,” Ms. Valentino said. “We look forward to analyzing the flight samples and continuing this program for future experiments.”