Linda Spilker spoke about the exploration of the fine structures in the atmosphere, the mass of the rings, and the magnetic field that Cassini's close orbits will accomplish. She mentioned that if Cassini can detect the tiniest offset between the magnetic pole and the spin pole, they might be able to answer the mystery of Saturn's day length. (Amazing, isn't it, that even after centuries of studying Saturn, we still don't know how long its day is or how much its rings weigh?)

Spilker explained that although Cassini is very nearly out of fuel, they do have a little bit of maneuverability left to respond to science results down to the very end. She said that the last five orbits in particular (the rightmost five blue lines in the diagram above) still have options to raise or lower their altitudes; the goal is to get Cassini's particle-scooping instruments as deep as possible into the atmosphere without going so deep that the spacecraft thrusters can't compensate for atmospheric drag. (If that were to happen, the spacecraft would tumble, and contact would be lost.)

Like the whole team, Spilker is proud of what Cassini has done and what it's doing about its final days. She's sad, too, contemplating the loss of the spacecraft. But there's another kind of loss she anticipates: the loss of "our intimate connection with Saturn." From Earth, we'll still be able to study Saturn's storm systems and the motions of its moons. But all those tiny structures in the rings, all the little ring-embedded moons, will be made invisible to us with the loss of Cassini. Once every fifteen years, she reminded us, we'll get to glimpse the ringmoons, as Earth crosses Saturn's ring plane. But that's it, until the next mission.

Here's a sampling of some of the images Cassini took last night. They're the first results of these close flybys of the planet.