Van Allen belt


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Van Allen belt

either of two regions of charged particles above the earth, the inner one extending from 2400 to 5600 kilometres above the earth and the outer one from 13 000 to 19 000 kilometres. The charged particles result from cosmic rays and are trapped by the earth's magnetic field
References in periodicals archive ?
The cause of the boundary repelling the electrons is not clear, but the researchers are focusing on the plasmasphere--a cloud of cold, electrically charged gas starting about 600 miles above Earth and extending into the outer Van Allen belt. Low-frequency electromagnetic waves in the plasmasphere that hiss like white noise could be causing the electrons to scatter and drift around the Earth in a loop, rather than toward the Earth.
But because the original Van Allen belts contain different types of particles, Van Allen himself thinks the trapped cosmic rays are one group within that inner radiation belt, he told SCIENCE NEWS.
While the Van Allen belts contain energetic electrons and protons, the new concentration of radiation is composed of so-called anomalous cosmic rays, which result when the solar wind interacts with atomic nuclei that originate in thin gas between the stars.
The Van Allen belts are important to study as they allow scientists to build a spacecraft with increased protection.
The researchers discovered that different energy levels of electrons in the Van Allen belts can lead to vastly different shapes and sizes of the belts themselves.
For example, modern computers are more susceptible to radiation than their 1960s counterparts, and the NASA-Lockheed Martin team wanted to see how they'd fare passing through the Van Allen belts. (The computers were shut off for 15 minutes during up and back passes and emerged unscathed both times.)
Preliminary test reports were encouraging: Not only did the capsule arrive intact, all eight parachutes deployed and onboard computers withstood the intense radiation of the Van Allen belts surrounding Earth.
However, in this case, the Earth's vast magnetic field, or magnetosphere, which contains the Van Allen belts, revs up drifting electrons to ever-higher speeds as they circle the planet from west to east.
The discovery could force scientists to revisit decades of ideas about the structure of the Van Allen belts, donut-shaped rings of radiation trapped in orbit by the planet's magnetic field.
The radiation belts (i.e., Van Allen Belts) also have some fairly intense radiation levels, but their locations are stable, predictable and can be mostly avoided with specific trajectories.
They passed through the enigmatic radioactive Van Allen Belts which extend from 4000 miles beyond the Earth, and with the interplanetary hunters steadily closing in, the astral forms of John and Ken entered the outer peripheries of Hades Belt, a vast semi-physical region encircling the earth, where many unquiet souls of our world go to.