News From Saturn
Transcript
Hi. I'm Shadan Ardalan, one of Cassini's navigators at NASA's Jet Propulsion Laboratory in Pasadena , with your report from the ringed planet.
Like most of you, Cassini is extremely busy in December, because all that the scientists and engineers want this season is more data. As a result, the spacecraft is completing full revolutions around Saturn every 16 days.
The Dec.5th Titan flyby was unique because Cassini was positioned to travel over Titan moving north to south.
This allowed our scientists to first get pictures of the Huygens landing site and then high-resolution images of dark lakes in the southern hemisphere, in particular one called Ontario Lacus.
But Titan isn't the only place Cassini is exploring.
There have been many great discoveries about Saturn's enigmatic rings and smaller moons.
Scientists believe that Saturn's rings are much older than originally thought.
Previous missions gave them the impression that the rings were formed perhaps 100 million years ago by a cataclysmic impact of a comet into a large moon.
Using a technique known as "stellar occultation", scientists acquired evidence that the rings appear to be older because smaller moonlets are recycling themselves.
This animation shows you how a "stellar occultation" works. By measuring the flickering of starlight as its passes through the rings, we are able to tell how thick the rings are, or if there is a more solid moonlet in the way.
The moonlets appear to be continually colliding into each other, shattering into ring particles, and then their gravity brings them back together to re-create new moonlets.
As we know here on Earth, recycling makes things last longer.
Scientists now believe that the rings may be as old as the solar system itself -- 4.5 billion years old.
Coming up on Dec. 20 th , Cassini's Radar instrument will have a historic opportunity to observe Titan's south pole.
The radar team will pierce through Titan's thick smog-like atmosphere in search of more lakes.
Cassini's trip into the deep south will mark its fourth of seven visits in the southern hemisphere planned in this campaign.
To keep up to date with the latest news from Cassini, please visit our website, "saturn.jpl.nasa.gov."
I'm 'Shadan Ardalan' from NASA's Jet Propulsion Laboratory.