> In astronomy, what's the term for the region of space where the sun's solar windhas a significant influence?And the answer: heliosphere.The sun sends out a constant flow of charged particles called the solar wind,which travels far beyond the planets, before being slowed down by gas and dustat the far reaches of our solar system. This forms a giant bubble around the sunand its planets, known as the heliosphere.Image Credit: By NASA Goddard Space Flight Center, CC BY 2.0The heliosphere isresponsible for electrically neutral gas, ionized gas, and interstellar dustthat form our solar system’s local galactic environment. Although its exactlimits remain unknown, it's thought to reach out some 9 or 10 billion miles –far beyond Pluto, at the edge of our solar system. The heliosphere interacts quite differently with planets, primarily dependingupon whether or not that planet has an internally generated magnetic field.Those that do – Earth, Mercury, and the outer planets – tend to have atmosphereswhich are protected from direct exposure to the solar wind by the terrestrialmagnetic field. Those that don't – Mars and Venus, plus our Moon – sufferatmospheric erosion by the solar wind, and greatly impact the climate of theplanet. Thanks to the bubble of the heliosphere, we are somewhat protected from anyrogue, charged particles that could potentially enter our solar system anddisrupt life as we know it. Now everyone say, "Thank you, Sun!" Learn more about the heliosphere below.