The Van Allen radiation belts are two regions of space located about 20,000 kilometers above the Earth and filled with energetic particles coming from solar winds. The high energies of these particles, trapped by Earth's magnetic field, can reach millions of electron volts, and can represent a hazard to satellites and humans in space. Now, an international team of scientists has explained the activity of the two Van Allen radiation belts and this will help protect astronauts and spacecrafts. By studying the solar storms of 2003 which disrupted GPS and communications satellites, they found that the old theory, which stated that the electrons within the belts were accelerated by radial diffusion, was wrong. Instead, they discovered that very low frequency radio waves caused the particle acceleration and intensified the belts. With this new information, it will be possible to take measures to protect astronauts, according to the researchers. Read more on ZDNet's Emerging Technology Trends.
Sources: British Antarctic Survey news release, via EurekAlert!, September 7, 2005; and various web sites
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