It soared 500 miles above the Earth’s surface nearly half a century ago, a silvery globe about the size of a large beach ball. Supposedly measuring cosmic rays from the sun in the interests of science, its true mission was to keep an eye on the Soviet Union’s air defense capabilities during the depths of the Cold War. One of America’s top military secrets at the time, the Galactic Radiation and Background satellite, launched in 1960, was the world’s first successful spy in space.

Little-known to the public even today, GRAB - like all U.S. satellites at the dawn of the Space Age - had a twin. Identical in all respects, these twins were manufactured as engineering models used for reference on Earth. Whereas GRAB never returned to Earth, GRAB’s double never left the ground.

Today, with the approach of the 50th anniversary of the launch of the Soviet satellite Sputnik in 1957, many doubles of early satellites are either in storage or, like GRAB’s, on display in the Smithsonian’s National Air and Space Museum in Washington, D.C.

The years on Earth have not been kind to these relics of the early Space Age. For instance, GRAB’s instrumentation was powered by six circular panels of solar cells set at intervals around the satellite. Each array contains 156 black cells arranged in rows like miniature dominos embedded in white cement. The surface of the solar cells has a metallic quality that appears to be corrosion. The ceramic adhesive holding them is cracking and turning to powder.

"Once this stuff falls apart, it’s gone forever," says Air and Space Museum Curator James David, who was alarmed by GRAB’s condition after he recently prepared it for display. He turned for help to Air and Space Museum Conservator Hanna Szczepanowska, a scientist involved in researching the materials used to make objects that are now museum artifacts.

Little information
Designed to perform in space, the materials used in the construction of these satellites were "expected to endure extreme fluctuations of temperature and exposure to intense light, vibration, radiation and atomic oxygen," Szczepanowska explains. On Earth, atmospheric moisture, oxygen and other forces are attacking the satellites. One offender, Szczepanowska says, may even be "corrosive off-gassing from some of the satellites’ storage materials." 

There is virtually no published information detailing the materials used to construct the GRAB satellite because of its reconnaissance mission, Szczepanowska says. In addition, as far as she can determine, no conservator has ever tackled satellite conservation in a systematic way. Little literature exists on the subject.

To address the problem, Szczepanowska began a collaborative research project. Her first objective is to conduct an analysis of the materials used to make the GRAB satellite. Knowing the exact materials will enable her to decipher the individual chemical processes responsible for their deterioration, she explains.

A second step will be to outline a conservation process to arrest further damage. Szczepanowska, in collaboration with a curator in the museum’s Space History Department, David DeVorkin, has expanded her efforts to include other satellites at the Smithsonian, including Vanguard I and Explorer VII.

Szczepanowska has secured the assistance of three important allies for the project: the U.S. Naval Research Laboratory, which built the GRAB satellite, and Paul Biermann and Edward Ott of Johns Hopkins University Applied Physics Laboratory, where many early satellites were designed.

Spectroscopy
Microscopic samples of materials from the satellites will be analyzed using mass spectroscopy and Fourier transform infrared spectroscopy. Other techniques will determine their molecular composition from the signatures of the light waves the material samples reflect. Examination with a binocular stereomicroscope, used in conjunction with a digital camera, will yield 3-D images of the physical characteristics of surface deterioration. This will enable Szczepanowska to diagnose the types and extent of damage.

Other laboratory techniques will yield further information about chemical composition inside the satellite’s materials. This is an important distinction. If changes are detected on the outer surface only, deterioration can probably be attributed to environmental forces. Internal degradation most likely would indicate the process of aging.

Szczepanowska has applied for a grant to support a one-year analysis of 27 satellites in the Air and Space Museum’s collections, which would result in a report setting forth guidelines for assessing the condition of space artifacts and recommending techniques for conserving them. She also plans to conduct a comparative analysis of the materials used to make early satellites and materials used today.

"These objects are an important part of our history," Szczepanowska says, "and their conservation is a fascinating new field. The knowledge I gain in this project will be shared with other museums around the world that are caring for objects designed for space."