Strong storms occur sporadically on Earth, but no matter how violent they are, they have nothing to do with those ofSaturn, whatjust suffered a string of storms that has lasted no less than 200 days. This storm season, the longest in twenty years, has been recorded in images and animations thanks to the probeCassini of the Cassini-Huygens mission, charged with unraveling the mysteries of the ringed planet.
The images and full-color animations show the birth of a storm of about 15,000 kilometers from north to south. In addition to the initial images, Cassini detected the electrical activity of the storm using its radio plasma instrument. Thanks to this information, scientists from Europe and the United States discovered that the electrical activity came from a convection storm. The last time a storm of this magnitude was recorded on Saturn was in 1903 and lasted 150 days.
“The Saturn storm is more like a volcano than those that occur in the Earth’s climate system,” said Andrew Ingersoll of the California Institute of Technology (Caltech, USA) and a member of the Cassini imaging team. “The pressure builds up for many years before the storm erupts, the most surprising thing is that there are no rocks to resist the pressure and delay the eruption for so many years,” Ingersoll points out.
In fact, according to his partner Kunio Sayanagi, this new storm is completely different from any other phenomenon observed on Saturn in advance by Cassini. “The fact that these outbursts are intermittent and occur on the planet with the rings every twenty or thirty years gives us clues about the processes that take place inside the planet and that we still have to investigate,” he suggests.
Cassini has obtained hundreds of images to be collected as part of the “Saturn Storm Watch” mission (Saturn Storm Watch, in English). These will be used to assess the storm among other scheduled observations of Saturn, its rings, and its satellites.
The Cassini-Huygens mission is supported by the United States National Aeronautics and Space Administration (NASA), the European Space Agency (ESA) and the Italian Space Agency (ASI).
