The mission for Cassini is simple: explore the Saturn System. The first leg of the mission was completed in June of 2008. The second leg, the Cassini Equinox Mission, was completed in September 2010. The third leg is scheduled to last until September 2017.
Cassini contains 12 instruments to send daily measurements of Saturn’s system. Among these instruments is a high resolution imager. Here is where it gets interesting (if you are thus far bored with AWESOME NASA STUFF!): Cassini arrived, as I said, in 2004. At this time Saturn was in the middle of its north polar winter. This means that the infrared imager on the spacecraft could see a giant vortex at the pole but the visible-light view was unattainable until August of 2009. Sunlight reached the northern hemisphere of Saturn and Cassini’s orbit had to be adjusted to be able to see the poles.
Hurricanes on Earth form from water vapor. The warm oceans feed a hurricane’s strength. The warmer the water the stronger the storm can be. Bottom line is that we thought that it takes a lot of water for a hurricane to form. On Saturn, there’s not much water at all.
Scientists believe that the storm is sustaining itself through the small amount of water available in the atmosphere of Saturn. Studying the hurricane on Saturn may help us to understand how hurricanes work here on Earth. Maybe hurricanes don’t need as much water as previously thought to develop into monsters? Definitely question scientists will investigate in the future.
The location of the hurricane on Saturn is interesting. Usually on Earth hurricanes drift to the north and dissipate as they reach colder water. This storm on Saturn is stuck at the North Pole. It literally can’t go anywhere else on the planet because of the air patterns.
So how long has it been there? Voyager saw something that looked odd 30 years ago. Cassini spotted a giant swirl at the North Pole in 2004. Obviously the storm has been there for quite some time and it will probably be there for some time to come. The good news is that Cassini is going to live and die in the Saturn system and will send measurements and pictures for years to come; however, Cassini can’t just hit the brakes and change its orbit. Scientists have to plan orbit changes with the gravitational pull of Saturn’s moon Titan. This requires careful planning years ahead of time to get it right. NASA is awesome.
Here is a video of the hurricane on Saturn that you should really check out: