The Cassini saw Saturn's auroras.

Auroras are formed around the magnetic poles of planets, when the charged particles of cosmic rays moving along the magnetic field of a celestial body, it reaches the atmosphere. Similar phenomena can be observed on Jupiter, Saturn, Earth, and some of the other planets of the solar system.

According to researchers, the distinguishing feature of Saturn’s auroras is their height — they rise by more than 1200 kilometers above the surface of the conditioned gas giant. For comparison, terrestrial auroras are formed at an altitude of 100-500 kilometers.

According to scientists, such a difference is explained by the different composition of the atmospheres of planets. On Earth, the main gases are heavy nitrogen and oxygen, so necessary for the emergence of radiance atmospheric density reaches a sufficiently low. On Saturn, the same large number of light hydrogen, so the lights and formed so highly.

Probe Cassini, which is a joint project between NASA and ESA, was launched in 1997 and reached Saturn in 2004. In 2008, in connection with the successes of the probe NASA has decided to extend the calculated for 4-year mission.