- the region around the sun over which the effect of the solar wind extends.
Origin of heliosphere
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
- the region around the sun outside of which the sun's influence is negligible and interstellar space begins
- 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.
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