Heliosphere

In Solar System, the heliosphere is the bubble of space dominated by the Sun and filled with plasma from the solar wind. Beyond the heliopause, this plasma escapes into interstellar space. The boundary between these two regions is called the heliosphere.

The shape of the heliosphere is determined by a balance between magnetic pressure from inside and ram pressure from outside. The sun’s magnetic field has been carried out into interstellar space by the solar wind to form a large bubble around everything in our solar system-the Heliosphere. This “bubble” protects us from harmful galactic cosmic rays that come from deep space beyond our solar system. It also affects how long it takes for comets to return after they are ejected out past Pluto’s orbit.

The size of the heliosphere is constantly changing as it responds to conditions in interstellar space beyond our solar system. As our sun moves through the Milky Way galaxy, it encounters different types of matter and energy that can compress or expand the heliosphere. For example, when our sun encounters dense clouds of interstellar gas and dust, they act like a snowplow pushing against the leading edge of the heliosphere causing it to contract inward. On the other hand, when our sun moves away from dense areas and into less dense areas of interstellar space, then there is less material for interaction causing an expansion outward of sorts for our protective bubble.. This constant ebb and flow due to interactions with different materials in interstellar space keeps our solar system nicely protected inside a giant cocoon -like structure-the Heliosphere!