heliosphere

nouns

the region inside the heliopause containing the sun and solar system
heliosphere
is a part of
the galaxy containing the solar system; consists of millions of stars that can be seen as a diffuse band of light stretching across the night sky
Milky Way, Milky Way Galaxy, Milky Way System
is a type of (narrower)
the extended spatial location of something
"the farming regions of France"; "religions in all parts of the world"; "regions of outer space"
part, region