We have long learned that the Sun and Jupiter are the largest stars in the solar system, which is not a lie, of course. The Sun composes about 99.8% of the entire mass of our system, and if Jupiter were hollow, it would fit more than 1000 Earths within it. Some astronomers even joke that the solar system is composed of only the Sun, Jupiter and some debris (which would be the other planets).
This large ball that gives us heat produces something that is larger than the star's own body. We're talking about the Heliosphere. It is an immense magnetic bubble that forms a kind of atmosphere of the solar system. And it is so large that it extends well beyond the orbit of Pluto, reaching up to 100 AU (considering that 1 AU is Earth-Sun distance). The boundary of this bubble is called the heliopause, which is where the heliosphere ends and reaches the interstellar gas outside the solar system.
This gigantic structure begins at the core of the Sun as millions of tons of hydrogen melt in helium every second. The resulting heat and other types of energy then rise toward the surface, carrying with it a handful of charged particles.
Just as the Earth's magnetic field is of extreme importance to us, the Heliosphere has the same weight. The bubble is a shield of much of the harmful cosmic radiation coming from distant galaxies, almost always from star bursts, thus protecting the celestial bodies within the solar system. [ NASA ]