Van Allen radiation belts

The ionosphere is part of the larger magnetosphere, a cavity in the stream of particles from the sun. The cavity is produced by the earth s magnetic field (56,57). The ionosphere and the Van Allen radiation belt He within the plasmasphere, which extends to a maximum distance of about 15,000 km... 

The discovery of the Van Allen radiation belt required a recalculation of this effect. Goldhaber and Nieto [49] used a recent survey and set the most accurate upper limit. A similar technique is to look at the magnetic field as a function of the distance from the earth using satellite data. An experimental term enters for a finite mass that would be distinguishable from the normal dependence of a magnetic dipole. Gintsburg set an upper limit using this method. 

Part of the solar wind is trapped in the magnetic field of the earth, forming the outer van Allen radiation belt, whereas more energetic solar protons are accumulated in narrow zones above the magnetic field of the earth, producing the auroral displays. 

Magnetosphere Region of the earth s magnetic field above the ionosphere, which is also the site of the high-energy trapped electrons constituting the Van Allen radiation belts. 

Development of new applications of radiation modifications of the properties of polymers in high technology industries such as electronics and the exposure of polymer materials to radiation environments as diverse as medical sterilization and the Van Allen belts of space have resulted in a renewed interest in fundamental radiation chemistry of polymers. 

The effects of the radiation flux in space on polymer materials is now of considerable importance due to the increasing use of communications satellites. Geosynchronous orbit corresponds to the second Van Allen belt of radiation, which comprises mainly electrons and protons of high energy. 

Astronauts would be subject to radiation from gedactic (0,05 rads per day) emd soleU (a few hundred rads per soleU fleU e) cosmic rays as well as leU ge fluxes of low energy radiation when passing through the Van Allen belts (about 0,3 rads per traverse). 

David DeLaney from the University of Tennessee s Physics Department suggested that Infinity World would not have a magnetic field, if the cylinder were hollow. This in turn would have extensive effects on navigation, the Van Allen belts, cosmic radiation, animals navigation, auroras, and so on. 

The study of the Sun during the IGY coincided and may have influenced the timing of the first artificial satellites launched by the Soviet Union (Spumik 1, October 4 and Spumik 2, November 2,1957) followed by Explorer 1 of the USA on January 31, 1958. At the request of James van Allen, the American satellite carried a Geiger Counter that detected the inner radiation belt that encircles the Earth (Victor 1964 Faure and Mensing 2007). 

An important question is what is the probable radiation dose during exposure to the space environment In outer space, unshielded structures may be exposed to as much as 3500 Mrads per day during a solar storm. Organic structures with minimum shielding are exposed to perhaps 10-15 rads per hour. Even at the upper level of 50 rads per hour (Van Allen belt), it would take 2,000,000 hours (229 years) to reach the 100-Mrad dosage level, and mot missions should be completed by that time. ... 

This overall concept of the terrestrial magnetosphere was rapid in developing once spacecraft were flown above the atmosphere. Soon after the discovery of the radiation belts (Fig. 3) by Van Allen and his studerrts rrsing... 

High specific energy to reduce the weight High radiation levels due to Van Allen belt crossing/proximity High reliability... 

The results mentioned above show that the hostile radiation fields in the inner and outer region of the Van Allen belt in space can be simulated. The radiation doses are no limitations to any space applications of Zerodur . 

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