Spacecraft Cassini is 
Visiting Saturn!

Why Name a Spacecraft Cassini?
Or a Probe Huygens?

How do you go about naming a spacecraft?
You think about what it is going to do, and then use your imagination!
Pioneer approaching Saturn For example, the first pair of spacecraft to ever fly beyond Mars were sent just to see if we could make it to Jupiter and Saturn. NASA engineers and scientists were reminded of the risky journeys of the early American settlers of the Old West, and called the two probes PIONEER.
After Pioneer, two more spacecraft went planet hopping, each visiting several of the outer planets. One went to all four gas giants: Jupiter, Saturn, Uranus, and Neptune! They traveled to many different "ports," and beyond! So NASA called them VOYAGER. Voyager flies over Saturn and takes pictures
Spacecraft Galileo with Jupiter and two of its moonsThen in the 1980s, a new kind of mission was planned. One spacecraft would fly out to Jupiter, but not pass it like the others. It would orbit it, and fly past the four big moons, Io, Europa, Ganymede, and Callisto, again and again. The first person to ever see Jupiter's moons was Galileo Galilei, an Italian astronomer. What better name for this spacecraft than GALILEO!

Which astronomers first looked closely at Saturn?
In the early 1600s, Galileo saw Saturn through his homemade telescopes, but he didn't know what its rings were. At one point he thought Saturn had ears! Galileo looks through a telescope at Saturn
Galileo draws two pictures of what he observes at Saturn and wonders why the planet seems to change Galileo decided that Saturn must have two large moons, one on each side, that didn't orbit Saturn but somehow just stayed stuck to the planet's sides. But a few years later, he didn't see anything around Saturn. Galileo didn't know what to think then!
No one could understand the strange shapes on either side of Saturn, which every 14 years or so would completely disappear! Then a Dutch astronomer named Christiaan Huygens (pronounced HOY ginz) made better telescopes with his brother. Through them, Huygens figured out that Saturn must have a detached, wide, thin ring! Christiaan Huygens looks at Saturn through a telescope and says to his brother, How about a Ring? Sounds good, replies his brother
Huygens drew this diagram to explain how Saturn could change its shape, because of its ring.
All the different shapes of Saturn are drawn to show how it tilts and sometimes shows a ring, and sometimes seems like a ringless planet
Picture of Saturn with the Cassini Division pointed out Jean Dominique Cassini, an Italian astronomer living in France, also studied Saturn. He watched the planet so much that he noticed a space inside the ring. There was more than one ring - there were TWO rings, he declared. This "gap" between the two main rings is still called the Cassini Division.
Cassini also guessed that the rings were really swarms of little moonlets, too small to be seen individually - and he was right! Now we know there are many rings, all composed of tiny particles and even some small moons. Picture of Saturn close up which shows its ring is really a swarm of little moonlets
Cassini the man
realized the true nature of Saturn's rings, so perhaps
a spacecraft named Cassini
can uncover even more of the truth
about Saturn and all those rings!
Both Huygens and Cassini built bigger and more powerful telescopes to find out more and more about Saturn.
Picture of Huygens Probe diving into Saturn Huygens discovered its largest moon, Titan, which we now know has an atmosphere. Spacecraft Cassini carries a probe which will dive into Titan's atmosphere and send back the first photographs of Titan's surface. The probe's name? Huygens!
Cassini discovered a new moon around Saturn almost every time he used a longer telescope to look at the planet. At one point, he had a water tower moved to the Paris Observatory, just to support a really long telescope! Drawing of the tower Cassini built at the Paris Observatory, to use as a telescope stand
Cassini was the first to see the moons later named Iapetus, Rhea, Tethys, and Dione. In those days, some people believed that if you had a really long, powerful telescope, you could even see animals on our moon!
A man stands at a huge long telescope, trying to see animals on the moon. You can just make out something that almost seems like a deer on the moon! But the telescope isn't long enough to tell for certain
What if Cassini and Huygens sometimes daydreamed about how wonderful it would be, not to have to use a telescope to see beautiful Saturn?
Cassini looks up with his telecope and sighs, Ah, to see exactly what the rings are made of! If only they could fly there, and see it all close up! The huge rings, the moons, the golden planet itself! Huygens looks up with his telescope and dreams, Ah, to walk on mysterious Titan!
If they did dream of that, those dreams are coming true!
Cassini will fly through Saturn's rings, and
Huygens will land on Titan!
What would they think of that?!?

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What's So Cool about Saturn?

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