Heliospheres: Cells in a Cosmic Ocean

A heliosphere is the vaguely spherical region of space where the pressure of the solar wind emanating from any given sun is sufficient to create a bubble of sparse plasma and a void in the interstellar medium, eventually terminating at the heliopause.

Are these cells or way too spherical heliospheres?

Strictly speaking — heliosphere refers only to the heliosphere of our sun, and solar wind, when that “wind” is not emanating from our own sun, “Sol”, is referred to as stellar wind. Stars have astrospheres, which is a term that encompasses the stellar wind bubble as well as the star’s magnetosphere.

The astrosphere can be considered to be, essentially, a far reaching extension of the outer atmosphere of a star, given that the astrosheath has a similarly shielding effect that the ozone layer does for the Earth for any planetary system inside it. The heliopause, for example, extends beyond the orbit of Pluto.

Credit to Wikipedia — not to scale, obviously. Let’s try to get the boring diagrams out of the way early!

The solar wind bubble of the sun’s heliosphere is created by the billowing clouds of plasma perpetually boiling off the surface of the sun, blasting outwards into space and eventually experiencing a “thermal shock” or “termination shock” as it reaches a distance where it’s own density is close enough to that of…