n.the magnetic field of a planet; the volume around the planet in which charged particles are subject more to the planet's magnetic field than to the solar magnetic field
N
the region surrounding a planet, such as the earth, in which the behaviour of charged particles is controlled by the planet's magnetic field 磁气圈; 包围着星球地带,内部的带电粒子的行为被此星球的磁场控制