Iapetus looms

[mmcirvin]

Crescent Iapetus from about 200,000 km away, as Cassini heads into today's long flyby. This overexposed picture shows more topography and some faint Saturnshine details. The height of the equatorial ridge is still startling. The raw image archive also has the elements of a big mosaic taken yesterday of Saturn and its inner moons as seen from the neighborhood of Iapetus.

Emily Lakdawalla has color composites of earlier images, and a few details on what's happening now. Here's her in-depth article on the encounter, with timeline.

It sounds as if these (or more like them) are the last pictures we'll get until sometime Tuesday, after the flyby is done. Cassini is going to be very busy in the meantime.

Update: I guess there were more from that downlink! Nice pictures here from a little under 70,000 km off. Notice how all those craters cover the equatorial ridge--it must be relatively old.

Comments

[mmcirvin.livejournal.com]

Iapetus is the only major moon of Saturn whose orbit is *not* essentially in the ring plane; it's got a significant inclination. But it's entirely possible that that was not always true.

The rings of Saturn are very, very thin. The tiny moon Atlas, which orbits in the outer part of the ring system, has an equatorial bulge that may well be from accumulated ring material--it looks a little like an elongated flying saucer.