Jupiter’s Magnetic Field Is 14 Times Stronger Than Earth’s

On Jupiter, compasses would actually function. That's because it boasts the Solar System's strongest magnetic field. Eddy currents, or the swirling motions of conducting materials, are thought by astronomers to be the source of the magnetic field within the liquid metallic hydrogen core. The sulfur and oxygen ions produced by the volcanic eruptions on Io are trapped in this magnetic field as sulfur dioxide particles. These combine with hydrogen ions from Jupiter's atmosphere to generate a plasma sheet in the planet's equatorial plane.

Further out, the solar wind and magnetosphere interact to produce a bow shock, a hazardous band of radiation that can harm spacecraft. The magnetosphere surrounds Jupiter's four largest moons, shielding them from the solar wind but also making it difficult to build colonies on their surfaces. Intense radio emission bursts from Jupiter's polar regions are also caused by the magnetosphere of the planet.