magnetosphere

noun

mag·​ne·​to·​sphere mag-ˈnē-tə-ˌsfir How to pronounce magnetosphere (audio)
-ˈne-
: a region of space surrounding a celestial object (such as a planet or star) that is dominated by the object's magnetic field so that charged particles are trapped in it
magnetospheric
mag-ˌnē-tə-ˈsfir-ik How to pronounce magnetosphere (audio)
-ˈsfer-
-ˌne-
adjective

Examples of magnetosphere in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The magnetosphere shields us from the Sun’s solar wind and solar storms, acting like a force field to keep living things safe from the energetic particles released by the Sun. Samuel Badman, The Conversation, 6 Oct. 2025 Juno's latest extension broadened its mission from studying Jupiter's interior and magnetosphere to include the planet's rings and observations of its large moons. Josh Dinner, Space.com, 6 Oct. 2025 Additionally, suspended 30 ft (9 m) is an intricate sculpture of Earth's magnetosphere, composed of 18 metal rings and 1,476 glass spheres. New Atlas, 3 Oct. 2025 Ejecta from its innermost large, volcano-rich moon, Io, populates this inner magnetosphere with sulfur dioxide gas, where the magnetic field forces this material to co-rotate with Jupiter itself in a torus-like shape. Ethan Siegel, Big Think, 3 Sep. 2025 See All Example Sentences for magnetosphere

Word History

Etymology

magneto- + -sphere

Note: Term introduced by the Austrian-born physicist Thomas Gold (1920-2004) in "Motions in the Magnetosphere of the Earth," Journal of Geophysical Research, vol. 64, no. 9 (September, 1959), pp. 1219-24.

First Known Use

1959, in the meaning defined above

Time Traveler
The first known use of magnetosphere was in 1959

Browse Nearby Words

Cite this Entry

“Magnetosphere.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/magnetosphere. Accessed 17 Oct. 2025.

Kids Definition

magnetosphere

noun
mag·​ne·​to·​sphere mag-ˈnēt-ə-ˌsfi(ə)r How to pronounce magnetosphere (audio)
-ˈnet-
: a region of space around an object (as a planet or star) that is dominated by the object's magnetic field

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