Glossary · Vật lý
Magnetosphere
The region around a planet dominated by that planet's own magnetic field. Earth's magnetosphere deflects most charged particles from the Sun and from space, and shields the atmosphere from erosion by the solar wind.
Earth's magnetic field is generated by the convective motion of electrically conducting molten iron in the outer core. That field reaches out into space and forms the magnetosphere.
The magnetosphere is not spherical; the solar wind distorts it. The sunward side is compressed to about six to ten Earth radii from the planet's centre. The night side is drawn out into a magnetotail hundreds of Earth radii long, far beyond the Moon's orbit.
Among the rocky planets of the Solar System, Earth has the strongest magnetosphere.