1. The region of space around the Sun that is dominated by the Sun's magnetic field and solar wind, extending to the heliopause where it meets the interstellar medium.
Usage: astronomy; physics

Examples

• The heliosphere protects the planets in our solar system from cosmic radiation.
• Solar wind particles constantly flow outward through the heliosphere.
• The Voyager spacecraft have traveled beyond the edge of the heliosphere into interstellar space.
• Earth's magnetic field interacts with the heliosphere to shield our planet.
• Scientists study the heliosphere to understand how the Sun influences the solar system.