Definitions for "Heliosphere"
The volume of space around the Sun which contains the charged particles and magnetic field carried in the solar wind. Its outer boundary (which has never been crossed) is called the heliopause and marks the beginning of interstellar space. This is thought to be 50 - 100 AU from the Sun.
The heliosphere is the region within the galaxy where the Sun's magnetic field dominates over magnetic fields from other sources in the galaxy. It is analogous, in some respects, to the description of the Earth's magnetosphere in relation to the Sun. Back to the top.
The entire large bubble of the Sun's influence that stretches far beyond the major planets