heliosphere

[ hee-lee-uh-sfeer ]
/ ˈhi li əˌsfɪər /

noun Astronomy.

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

Origin of heliosphere

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

British Dictionary definitions for heliosphere

heliosphere
/ (ˈhiːlɪəʊˌsfɪə) /

noun

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

Scientific definitions for heliosphere

heliosphere
[ hēlē-ə-sfîr′ ]

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