Saturn's magnetic field is far less than Jupiter's, and unlike the more strong Jovian radio emissions, Saturn's radio signals are insufficient to be detected from Earth. However, like Jupiter, it does have a magnetosphere that extends out from around its orbit for many millions of kilometers.
Saturn's magnetosphere is much smaller than Jupiter's though, only about 5 million km across at its largest. Also, like Jupiter it has a strong internal magnetic field which causes its atmosphere to rotate with the planet instead of flowing like the gas giants' atmospheres. This magnetic field causes chemical reactions in Saturn's atmosphere that produce clouds and rain that flow toward the equator where they are collected into bands on Saturn's surface.
In addition to being smaller and having a stronger internal magnetic field, Saturn also has a much less active dynamo than Jupiter does. Because of this, scientists think that perhaps there was a time in Saturn's history when it had an even larger internal magnetic field than it does today, but because it didn't generate any electrical currents within itself, it collapsed after some time.
Another interesting thing about Saturn is that it has a network of interconnected atmospheric layers called'super-rotations'. These can be seen in the visual imagery from space as bright and dark bands that circle the planet once every 10 days or so.
Jupiter's magnetosphere is an order of magnitude greater than Earth's, and its magnetic moment is nearly 18,000 times bigger. The magnetic fields of Venus, Mars, and Pluto, on the other hand, are non-existent.
Jupiter's magnetosphere extends for more than 600 million km around the planet. It consists mainly of electrons that have been stripped from Jupiter's atmosphere by its intense radiation field. These electrons form a shell that surrounds Jupiter like a bubble. Inside this shell, particles can travel close to the surface without being affected by the planet's gravity.
The magnetosphere also contains positive ions arising from the dissociation of molecules in Jupiter's atmosphere, as well as protons and alpha particles emitted by the planet's interior. The magnetosphere is constantly changing because these particles are swept into space when they are ejected from one region of the planet's surface then reappear somewhere else.
Earth's magnetosphere is much smaller than Jupiter's but it still spans about 400 million km around our planet. It protects us from many dangerous particles streaming out of the Sun every day. These particles could easily destroy any aircraft or spacecraft traveling near the Earth if they were not protected by the magnetosphere. The magnetosphere is also responsible for the stability of Earth's magnetic field - without it, we would be exposed to even more destructive cosmic rays.
Saturnian atmosphere Saturn is colder and further away from the Sun. It reduces the chemical complexity of the bands, making them considerably more faint and less colorful than Jupiter's. The only truly red feature on Saturn is its equator, which is made up of strong winds that blow across a layer of hot liquid rock.
Saturn was once thought to be a planet like our own, but now we know it has many features not found on Earth. It has seven large moons, all of which have been very helpful in understanding how planets form and evolve. Tethys, for example, shows how important it is for a world to start off with a dense core surrounded by a thin shell of ice. Dione provides evidence that there can be more than one moon per planet. Rhea has an extremely eccentric orbit, which causes it to come close in to Saturn several times every year. This makes it possible for scientists to study the effects of gravity over time.
Saturn was originally discovered by Johann Gottfried von Leibniz in 1655, but it wasn't until much later that it was confirmed as a new planet. The first spacecraft to fly by Saturn was NASA's Cassini-Huygens mission, which arrived at Saturn in 2004.
It is thought that the magnetic fields of Saturn and Jupiter are created by hydrogen carrying electricity deep beneath the planets. Hydrogen at the planet's core may be crushed so tightly by the planet's layers above that it forms an electrical conductor. If this is true, then other elements in the solar system might also possess magnetic properties.
The origin of Earth's magnetic field is not well understood. It may be that hydrogen does play a role in generating the field, but current theories suggest that another process is involved as well.
A planetary magnetic field can influence the weather on its surface. On Earth, the field is responsible for creating our familiar magnetosphere that shields us from some of the particles streaming from the sun. But beyond our atmosphere the magnetic field of Jupiter could well extend far enough to surround Saturn, thereby protecting it from many of the charged particles thrown out into space by the giant planets.
Magnetic fields may also help planets retain their atmospheres. Without a strong magnetic field, Earth would lose its atmosphere because of the solar wind - continuous streams of electrons that flow from the sun into space. However, Jupiter and Saturn have magnetic fields which protect them from most of the particles coming from the sun. This suggests that they too retain their atmospheres despite being much farther away from the sun than Earth is.