magnetosphere

American  

[mag-nee-tuh-sfeer] / mægˈni təˌsfɪər /

noun

Astronomy.

1. the outer region of the earth's ionosphere, where the earth's magnetic field controls the motion of charged particles, as in the Van Allen belts.

2. such a region of another planet.

   Jupiter's magnetosphere.

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magnetosphere British  

/ mæɡˈniːtəʊˌsfɪə /

noun

1. the region surrounding a planet, such as the earth, in which the behaviour of charged particles is controlled by the planet's magnetic field

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magnetosphere Scientific  

/ măg-nē′tō-sfîr′ /

1. A highly asymmetrical region surrounding the Earth, beginning about 100 km (62 mi) above the surface on the side of the Earth facing the Sun and extending hundreds of thousands of kilometers into space on the opposite side. In this region the Earth's magnetic field exerts a significant influence on any charged particles that encounter it. The magnetosphere deflects most of the charged particles in the solar wind, but also traps and deflects some of these particles toward the Earth's magnetic poles, causing magnetic storms and auroras.

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Other Word Forms

• magnetospheric
  adjective

Etymology

Origin of magnetosphere

First recorded in 1955–60; magneto- + -sphere

Example Sentences

See Examples For:

magnetosphere

One day on the planet lasts approximately 10.7 hours, and its magnetosphere also contains large amounts of ionized material supplied by its moon Enceladus.

From Science Daily ● Aug. 10, 2026

The researchers also propose that heavy noble gases in lunar soil could act as "fossil records" of earlier interactions between the solar wind and Earth's magnetosphere.

From Science Daily ● Jul. 21, 2026

An analysis of material collected by China's Chang'e 6 mission now suggests that Earth's magnetosphere is responsible for much of this contrast.

From Science Daily ● Jul. 21, 2026

In minutes, sunlight would ionize the material, creating a plasma barrier that would flow to the day-side of the magnetosphere.

From The Wall Street Journal ● Jul. 10, 2026

Anything potent enough to put on such a show could well blow away the magnetosphere, the magnetic zone high above the Earth that normally protects us from ultraviolet rays and other cosmic assaults.

From "A Short History of Nearly Everything" by Bill Bryson