heliosphere
/ˈhiːlioʊˌsfɪr/
noun
- The region of space around the sun that is filled with solar wind and magnetic fields, extending far beyond the planets.
- Scientists study the heliosphere to understand how the sun interacts with the rest of the galaxy.
- The heliosphere acts like a giant bubble, protecting our solar system from cosmic rays.
- The Voyager spacecraft finally left the heliosphere and entered interstellar space.