The new visualization may help experts understand the gas giant better

Feb 12, 2014 08:37 GMT  ·  By

Recently, a team of astronomers at the University of Leicester, in the United Kingdom, has used the capabilities of the NASA/ESA Hubble Space Telescope and the NASA Cassini orbiter to produce an accurate, in-depth visualization of the auroras dancing around Saturn's poles. 

Hubble was able to observe the event from its orbital perch around Earth, using its ultraviolet sensors. Cassini contributed infrared, visible light and ultraviolet data, collected from its orbit around the planet.

The advantages of using Cassini for collecting these close-up views is that the orbiter is capable of observing areas on both the northern and southern hemisphere of the gas giant that do not face Earth, and are therefore invisible to Hubble.

The auroral choreography at Saturn's poles was dissected step-by-step in the new study. This enabled astronomers to discover additional details of how these structures move, as well as figure out just how complex they actually are. These amazing lights are produced when solar radiations hit the planet's magnetosphere.

Therefore, every outburst produced by the Sun can be linked to an intensification of auroral displays at Saturn. A similar effect can also be seen on Earth, but not on Mars. Our neighboring world lacks an actively spinning iron core, meaning that it has no protective magnetic shield.

“Saturn's auroras can be fickle – you may see fireworks, you may see nothing. In 2013, we were treated to a veritable smorgasbord of dancing auroras, from steadily shining rings to super-fast bursts of light shooting across the pole,” says UL astronomer Jonathan Nichols, who led the Hubble observations.

“This is our best look yet at the rapidly changing patterns of auroral emission. Some bright spots come and go from image to image. Other bright features persist and rotate around the pole, but at a rate slower than Saturn's rotation,” adds expert Wayne Pryor, a Cassini investigator based at the Central Arizona College.

The new study also goes a long way towards explaining why the atmospheres of gas giants, including Saturn and Jupiter, are hotter than they should be so far away from the Sun. Researchers say that auroras are partially responsible for this effect, heating the atmosphere wherever they touch it.

“As we move into the part of the 11-year solar cycle where the Sun is sending out more blobs of plasma, we hope to sort out the differences between the effects of solar activity and the internal dynamics of the Saturn system,” says Cassini fields and particle scientist Marcia Burton, who is based at the NASA Jet Propulsion Laboratory. She helped coordinate the new observations.