Hubble telescope spots 'northern lights' on Saturn

Over a period of seven months in 2017, the Hubble Space Telescope photographed a beautiful display of northern lightsover Saturn's north pole.

Here on Earth, peopleexperience the northern lights (southern lights in the southern hemisphere) when fast-moving particles from the sun travel along the solar wind and interact with the planet'smagnetic field.

Auroras, also called the northern or southern lights, arecaused by charged particles moving down toward the poles and then interacting with molecules of nitrogen and oxygen which transform the sky into bright bands of green, red and violet lights.

Earth isnot the only planet toexperiencethis spectacular phenomenon.The giant outer planets Jupiter, Saturn, Uranus and Neptune also get northern and southern lights.

Here on Earth, peoplecan look up and appreciate the colourful display, but it's a little different with planets like Saturn which are mostly made of gas. Because these planets contain mostly hydrogen, the displays can be seen mainly in ultraviolet light.

To capture the northern lights, Hubble used its Space Telescope Imaging Spectrograph over the months before and after Saturn's northern summer solstice, when the poles are tilted toward the sun.

Hubble Space Telescope spots aurora on Saturn

6 years ago

Duration 0:20

The Hubble Space Telescope spotted northern lights dancing above Saturn's north pole. Credit: ESA/Hubble, NASA & L. Lamy (Observatoire de Paris)

Though Saturn's auroras have been photographed before by Hubble, these new images revealthe auroras peaking in brightness around dawn and just before midnight.

This had never been observed before. Scientists believe the phenomenon has something to do with solar winds interacting with the planet's magnetosphere during the solstice, as well as the speed at whichSaturn rotates, roughly once every 11 hours.

While Earth's auroras stretch upwardaround 100 to 500 km into the atmosphere, Saturn's auroras can reach heights of more than 1,200 km.