heliopause

[ hee-lee-uh-pawz ]
/ ˈhi li əˌpɔz /

noun Astronomy.

the boundary of the heliosphere.

Origin of heliopause

First recorded in 1970–75; helio- + pause

British Dictionary definitions for heliopause

heliopause
/ (ˈhiːlɪəʊˌpɔːz) /

noun

the boundary between the region of space dominated by the solar wind and the interstellar medium

Scientific definitions for heliopause

heliopause
[ hēlē-ə-pôz′ ]

The region surrounding the solar system at which pressure from the outgoing solar wind equals the pressure from the interstellar medium (made up mostly of hydrogen and helium), and the solar wind can penetrate no further. It is considered to be the outer boundary of our solar system. See more at solar wind.