Washington: Data gathered by NASA`s Lunar Reconnaissance Orbiter (LRO) have shown that lighter materials like plastics provide effective shielding against the radiation hazards faced by astronauts during extended space travel.
The finding could help reduce health risks to humans on future missions into deep space, according to space scientists from the University of New Hampshire (UNH) and the Southwest Research Institute (SwRI).
Aluminum has always been the primary material in spacecraft construction, but it provides relatively little protection against high-energy cosmic rays and can add so much mass to spacecraft that they become cost-prohibitive to launch.
The work is based on observations made by the Cosmic Ray Telescope for the Effects of Radiation (CRaTER) on board the LRO spacecraft. Lead author of the paper is Cary Zeitlin of the SwRI Earth, Oceans, and Space Department at UNH. Co-author Nathan Schwadron of the UNH Institute for the Study of Earth, Oceans, and Space is the principal investigator for CRaTER.
"This is the first study using observations from space to confirm what has been thought for some time-that plastics and other lightweight materials are pound-for-pound more effective for shielding against cosmic radiation than aluminum. Shielding can`t entirely solve the radiation exposure problem in deep space, but there are clear differences in effectiveness of different materials," said Zeitlin.
The CRaTER observations have validated the models and the ground-based measurements, meaning that lightweight shielding materials could safely be used for long missions, provided their structural properties could be made adequate to withstand the rigors of spaceflight.
The scientists have published their findings online in the American Geophysical Union journal Space Weather.