How were Saturn's famous rings formed? Cassini is helping scientists look for answers. Plus, upcoming flybys of Saturn's moons Titan and Iapetus.


Hello, I'm Powtawche Williams. Welcome to NASA's Jet Propulsion Laboratory in Pasadena, California. I'm a Maneuver Analyst on the Cassini Navigation Team. Here's how you can think of my job. I'm the person in the car with the map, giving the driver directions and estimating how much gas is left in the tank on a road trip. The navigation team plays a similar role for the Cassini spacecraft, as it flies around Saturn.

Cassini scientists are trying to figure out how Saturn's famous rings were formed. The G-ring is one of the outer rings, near the heavily-cratered moon Mimas. Cassini scientists say this G-ring was likely produced by large, icy particles within a bright arc on the inner edge. The large icy particles are stuck by tiny meteoroids to create smaller, finer particles swept out by Saturn's plasma drifting from the arc, filling in the ring.

Cassini flew by Saturn's moon, Titan on July 19. One of the objectives was to determine the nature and surface composition of a location just west of the Huygens landing site. Scientists also checked out seasonal changes on the moon. On August 31 we'll be returning for another flyby of Titan. It'll be an opportunity for us to get images of Titan's surface, near the Huygens landing site.

On September 10th, we'll make our closest flyby ever of one of Saturn's most intriguing moons Iapetus. Half of it looks as dark as asphalt, while the other half appears bright as snow. We'll be taking high-resolution observations, so scientists can study the boundary between the light and dark regions. They'll also check out the mountainous ridge discovered by Cassini in December 2004.

All pretty exciting stuff. I'm Powtawche Williams from NASA's Jet Propulsion Laboratory with your Cassini update.

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