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This is an artist's conception of the Earth and the inner and outer radiation belts that surround it.
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Radiation Belts

The Earth's radiation belts are just one part of the system called the magnetosphere. The radiation belts of the Earth are made up of electrons, protons and heavier atomic ions. These particles get trapped in the magnetic field of the Earth.

The radiation belts, like the plasmasphere, are toroidally shaped. There is an outer and an inner radiation belt.

The belts of trapped radiation near the Earth were discovered by James Van Allen in 1958. Therefore these belts are also known as Van Allen Belts.

It is really important that we have a good understanding of the radiation belts because the particles in these belts can be dangerous to humans, animals or even electronic equipment that flies in this area. "The particle population of the Earth's radiation belts makes it dangerous for humans without massive shielding to do more than quickly pass through them," reports Dr. James Van Allen.

Last modified May 27, 2003 by Lisa Gardiner.

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Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA