Magnetosphere
Forces deep inside Saturn create a giant magnetic bubble around the planet, called the magnetosphere, which exerts a powerful influence on particles that float through space near the planet. Saturn's magnetic field creates this bubble as material cycles deep within the planet's fluid interior. In a similar way, Earth's magnetic field creates a much smaller magnetosphere that protects us from harmful particles emitted by the sun and other space phenomena.
Outside Saturn's magnetosphere, a million-mile-per-hour gale of particles from the sun, called the solar wind, spreads out through the Solar System. When the solar wind encounters Saturn's magnetosphere, it streams around it, like a stream around a rock. So outside the planet's magnetosphere, the sun's magnetic forces dominate, while inside the planet's protective bubble, magnetic forces of Saturn reign.
Saturn's magnetic field has north and south poles, like those on a bar magnet, and the field rotates with the planet. On Jupiter and Earth, the magnetic fields are slightly offset from the planets' rotation axes – this offset is the reason we say compass needles point to "magnetic north" rather than true north. But Saturn's magnetic field is almost perfectly aligned with the planet's rotation.
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