heliosphere

American  

[hee-lee-uh-sfeer] / ˈhi li əˌsfɪər /

noun

Astronomy.

1. the region around the sun over which the effect of the solar wind extends.

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heliosphere British  

/ ˈhiːlɪəʊˌsfɪə /

noun

1. the region around the sun outside of which the sun's influence is negligible and interstellar space begins

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heliosphere Scientific  

/ hē′lē-ə-sfîr′ /

1. The large, roughly elliptical region of space around the Sun through which the solar wind extends and through which the Sun exerts a magnetic influence. The heliosphere extends well beyond the orbits of the planets, and its shape and extent fluctuate with changes to the solar wind and other influences.

2. ◆ The boundary between the heliosphere and interstellar space is known as the heliopause.

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Etymology

Origin of heliosphere

First recorded in 1970–75; helio- + -sphere

Example Sentences

Others think these observations help show that Voyager 1 still hasn’t completely left the heliosphere.

From Science Magazine • May 23, 2024

Astrospheres, stellar analogues of the heliosphere that surrounds our solar system, are very hot plasma bubbles blown by stellar winds into the interstellar medium, a space filled with gas and dust.

From Science Daily • Apr. 12, 2024

The heliosphere extends out to about 100 to 120 times further than Earth's distance to the sun.

From Reuters • Aug. 24, 2023

But it no longer needs to wait, and the mission has resumed data transmissions from beyond the solar system’s heliosphere.

From New York Times • Aug. 4, 2023

Voyager 2 and its twin Voyager 1 are the only spacecraft ever to operate outside the heliosphere, the protective bubble of particles and magnetic fields generated by the Sun.

From BBC • Aug. 1, 2023