Radiant rings and a planet-sized moon make Saturn mysterious and alluring. Three spacecraft had made flybys of the planet before Cassini-Huygens was launched in 1997. The launch followed nearly two decades of planning, and this mission was going to get up close and personal.
Cassiniís three missions
NASAís Cassini orbiter was named for Jean Dominique Cassini, a prominent 17th century Italian-French astronomer who made important observations of Saturn. It was due to spend four years studying the ringed planet and its moons. Even more ambitious was the Huygens lander, named after Cassini's Dutch contemporary Christiaan Huygens who discovered Titan, Saturnís largest moon. European-built Huygens would separate from the orbiter and land on Titan. You can see the picture taken from the surface of Titan.
Very soon after its arrival in 2004 Cassini was sending home detailed pictures. They wowed the public. And they had planetary scientists happy, but seriously in need of revising some of their theories.
My favorite picture is one released in October 2006. Not only is it stunning, but if you look outside of the bright central rings to the left, just inside the next ring out, there is a small dot. It could be a moon. But itís distant Earth.
The mission was so successful that in 2008 it was extended for two years, becoming the Cassini Equinox Mission. In 2010, as the Cassini Solstice Mission, it was further extended until September 2017.
But what is significant about September 2017? It has to do with Saturnís seasons. The planetís axis tilts by 27 degrees, so like Earth it has seasons. Unlike Earth it takes thirty years to orbit the Sun, so its seasons are much longer. When Cassini first arrived at Saturn it was just after the northern hemisphere's summer solstice. The southern summer solstice occurs in September 2017, so Cassini will have studied the planet for two seasons.
The Cassini website is part of the site of the Jet Propulsion Laboratory (JPL) of the California Institute of Technology. The home page contains a set of menus, each with its own drop down-menu. They are: About Saturn & Its Moons, News & Features, Images, Video & More, Mission Overview, Inside the Spacecraft, and Education. Yet the most prominent feature of the page is the latest images and videos. There is also a countdown for Cassiniís next encounter and a link to diagrams showing the craftís current location.
For anyone interested in the mission or the planet, there is explanatory text, pictures and video. But I think the best feature of the website must be the superb pictures of the Saturnian system - not only a big selection of recent ones, but also the Cassini Hall of Fame. The very first picture in the Hall of Fame is the one that I described above, but many more follow. The only downside is the amount of time that can be frittered away when you should be doing other things!
People can also access raw images, the unprocessed picture data. Space probes donít send pictures, but send data containing the information to produce a picture. The pictures released to the public have been processed, but some people like to do their own image processing for aesthetic or scientific purposes.
I looked carefully at the material for educators and can recommend to elementary school teachers that they have a look at the Language Arts/Science Elementary School Program. Itís a well thought out program to integrate language skills with science learning, referring to the relevant USA standards, explaining the purpose of various activities and listing resources. There are a number of broken links, but I donít think theyíre essential. The whole program is a downloadable PDF.
The middle school materials include Saturn in Your Kitchen (ďInquiryĖbased activities featuring Cassini Science and EngineeringĒ) and Saturn Educator Guide. All activities are downloadable PDFs. The listed materials in my kitchen, but science teachers might find something to enhance the curriculum.
The Saturn Educator Guide is supposed to be available in book form, but good luck on finding it. However it's all on downloadable PDFs. I looked through the first four activities and there is a lot of good material.
For pupils doing projects, the Fun Facts in Kids Space are good and About Saturn and Its Moons would be helpful. There is also a page where you can look for images of any of the moons, or Saturn, or the rings.
There are whole sections that contain only outdated material. The Saturn Observation Campaign doesn't seem to exist anymore. There is information for viewing Saturn, but no links to events go anywhere. Some of the Classroom Materials are available and worth a look for high school teachers. Links to several NASA sites return a "page not found" error.
If I were an enthusiastic kid Iíd be pretty disappointed in the Kids Space section. Activities promises an activity book, but delivers one coloring sheet. Youth Groups doesnít deliver anything. There's not much inspiration there.
I would still give the site an overall 7/10 because of the pictures and the news updates on a fascinating planetary mission.
Cassini Mission, http://saturn.jpl.nasa.gov (accessed 2013-11-13)
There are a number of Cassini images on my Pinterest board Saturnís moons.
(Article last updated 2015-09-19)