Here's the Story Behind Those Lights at Saturn's North Pole

Stunning ultraviolet images captured by the Hubble Space Telescope show bursts of light zipping around Saturn.

These are aurorae, created as the planet's magnetic field is battered by charged particles from the sun. Scientists studying the auroras say this latest data finally reveals the unseen dynamics in the choreography of the dancing lights.

University of Leicester astronomers say the images are a "smoking gun" for their theory that Saturn's auroral displays are often caused by the dramatic collapse of its "magnetic tail."

Just like comets, planets such as Saturn and the Earth have a "tail"— known as the magnetotail— that is made up of electrified gas from the sun and flows out in the planet's wake. When a particularly strong burst of particles from the sun hits Saturn, it can cause the magnetotail to collapse, with the ensuing disturbance of the planet's magnetic field resulting in spectacular light shows.

Due to the composition of Saturn's atmosphere, its auroras shine brightly in the ultraviolet range of the electromagnetic spectrum. Some of the bursts of light seen shooting around the planet travelled at over three times faster than the speed of the gas giant's rotation.

"These images are spectacular and dynamic, because the auroras are jumping around so quickly," explains astronomer Jonathan Nichols, who led the Hubble observations. "We can see that the magnetotail is undergoing huge turmoil and reconfiguration."

The findings of the research will be published in the journal Geophysical Research Letters.

[Via ESA and the University of Leicester]