Van Allen belt (redirected from Van Allen layers)

Van Al·len belt  (vn ln)

n.

Either of two zones of high-intensity particulate radiation trapped in Earth's magnetic field and surrounding the planet, beginning at an altitude of about 800 kilometers (500 miles) and extending tens of thousands of kilometers into space.

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[After James Alfred Van Allen (1914-2006), American physicist.]

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Van Allen belt [væn ˈælən]

n

(Earth Sciences / Physical Geography) 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

[named after its discoverer, James Alfred Van Allen (born 1914), US physicist]

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Van Allen belt  (vn ln) Either of the two zones surrounding the Earth in which a thin distribution of atomic particles with very high energies are trapped by Earth's magnetic field. The inner belt lies between about 500 and 6,440 km (310 to 4,000 mi) above Earth's equator and consists mostly of a mix of protons and electrons. The upper belt lies between about 15,000 and 30,000 km (9,300 to 18,600 mi) and consists mostly of protons. Both belts are thickest at the equator and have irregular densities of particles. The outer radiation belt is much larger and the number of particles varies, increasing in the aftermath of solar flares. The polar auroras are caused when some of the charged particles from the outer Van Allen belt hit the upper atmosphere. The Van Allen belt is named after its discoverer, American astrophysicist James Van Allen (born 1914).

Van Allen belt Positively and negatively charged particles (mostly protons and electrons) are trapped in the inner Van Allen belt, and negatively charged particles are trapped in the outer Van Allen belt.

Thesaurus

Noun

1.

Van Allen belt - a belt of charged particles (resulting from cosmic rays) above the Earth trapped by the Earth's magnetic field earth, globe, world - the 3rd planet from the sun; the planet we live on; "the Earth moves around the sun"; "he sailed around the world"