Planetary Magnetospheres

Abstract

A magnetosphere is not a typical terrestrial phenomenon. Instead, magnetospheres can be found around all magnetized bodies embedded in a plasma flow. Even around unmagnetized bodies (comets, planets without a magnetic field) a cavity is formed by the interplanetary magnetic field frozen into the deflected solar wind flow. In the solar system, all planets except Mars and Venus have a magnetosphere. Although they are different in size, for most of them the shape and the properties of the magnetosphere are similar to those in the terrestrial one. Special features are the large size and the flat inner structure of the Jovian magnetosphere and the oscillation of Neptune’s magnetosphere between pole-on and Earth-like.

Empty space is like a kingdom, and heaven and earth are no more than a single individual person in that kingdom ... How unreasonable it would be to suppose that besides the heaven and earth which we can see there are no other heavens and no other earths?

Tang Mu, 13th century