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Video podcast: Postcards From Saturn, Cassini's Tale of Two Moons
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Halfway through its 4-year Saturn tour, Cassini's travel log is brimming with news. One amazing discovery after another, like postcards from an excited tourist, information streams home.

Trina Ray, Cassini Science Planner:
"I think it was beyond what we could’ve imagined.
Data set being returned from Cassini is extraordinarily rich. Scientists will be studying it and learning about the Saturn system for decades after the mission is over."

A high priority destination - Saturn's largest moon, Titan. NASA's Voyager mission spotted an intriguing orange ball 25 years ago. Cassini went back for a closer look.

(Sounds of Titan)

On January 14, 2005, Cassini released the Huygens probe, with its cameras rolling and a microphone recording.

(Audio from Titan)

It revealed a place that is strikingly Earth-like.

Cassini has flown by Titan more than a dozen times in two years.

Rosaly Lopes, Cassini Scientist:

"Titan has this thick atmosphere and we use the radar to be able to see the detailed geology."

Steve Wall, Cassini Scientist:

"We can see little swirls and inlets and outlets. Things you might think of as Bays. We know that the materials at Titan are distinctly different from what we find on Earth. You don't find the same materials and yet you find the same processes going on. That's really exciting."


While scientists expected lots of discoveries at the big moon Titan, one of the biggest surprises has been from the small moon Enceladus.

Trina Ray:

"Here is this tiny, tiny, tiny little moon. It has geysers shooting out of the south pole. If you catch it in the right light Enceladus will show you, sort of these jets and they're huge. They extend almost the size of the moon itself. Just amazing…amazing.."


They call it "Cold Faithful" because of its similarities to the hydro thermal system powering Old Faithful in Yellowstone. All the evidence points to possible water near the surface. It's one of the numerous discoveries that will ensure Cassini's spot in history.

Trina Ray:
"We will be learning about the Saturn system for decades after the mission is over. I can't begin to estimate how many young scientists will do a PhD dissertation on Cassini data. The number is going to be staggering."

Cassini's passport is only half-filled. Its itinerary over the next two years includes dozens of flybys of Titan, Enceladus, Saturn's other moons and its rings. We can expect more postcards from our Saturn tourist as its travel journal bulges with new discoveries.