particles can play havoc with satellites. Spacecraft damage includes decreased power production by solar arrays, failure of sensitive electronics, and increased background noise in sensors. Furthermore, there is always the concern of radiation exposure to humans in orbit, specifically long-term crews aboard the International Space Station.
Space experiments carried out via the LWS initiative include flying new types of commercial and government microelectronics technologies; advanced radiation shielding; and a range of high-tech sensors, Hardage said. Modern electronics are becoming increasingly sensitive to ionizing radiation.
"Trying to get electronics to function in the space environment gets tougher every day," Hardage said. "As the electronics get smaller and faster, you can't avoid being hit by an ion coming from the sky. The smaller the electronics, the more susceptible. By adding more shielding, you add more weight and it becomes costlier. Everything starts going up," she said.
NASA's Space Environments and Effects (SEE) program, Hardage said, studies electromagnetic effects and plasma/spacecraft charging, meteoroid impacts, ionizing radiation, and other phenomena that can damage satellites and human-carrying spacecraft.
Hardage said that new materials offer promise for radiation shielding. Testing those materials in space is critical. As example, one recently flown shielding material was found to actually make the situation worse, not better, she said.
Studying human-made orbital debris is also part of the SEE activities. Space junk can be as large as spent rocket motors and as small as the dust particles ejected from the nozzles of maneuvering thrusters, Hardage explains.
"The more you know, the more you can protect your satellites and equipment," said "You can plan for and mitigate some of the effects. The more prepared you are the better," she told SPACE.com.
"Nowcasting" the future
Space weather forecasting has grown in importance over the years, said W. Kent Tobiska, president of Space Environment Technologies (SET) in Pacific Palisades, California. He is also chief scientist of SpaceWx, a division of SET. SpaceWX provides space weather information and forecasting technologies, specializing in solar irradiance variations.
Tobiska stressed that our global economy of today is increasingly dependent on technologies and industries affected by changes in space weather. "Near-Earth space is becoming more populated with civilian and military satellites that link our commercial, research, and defense infrastructure," he said.
Thanks to increasing scientific data regarding the Sun's doings, coupled with SpaceWX products, Tobiska said that short-term "nowcasts" of near-Earth space conditions are possible. A range of nowcast and forecast predictions -- stretching from 24-hour, 72-hour, 14-day, 28-day, and 6-month periods, out to 11-year and 55-year time periods -- are possible using various cutting-edge computer and software techniques, he said.
By predicting solar activity, commercial and governmental spacecraft operators can better prepare for blasts of radiation that can affect satellite orbits, disrupt radio telecommunications, and interfere with Global Positioning System (GPS) navigation satellites. Longer-term predictions can also project the levels of radiation hazards to aircraft and spaceflight crews throughout different periods of the solar cycle, Tobiska said.
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