This observation of Mimaldi shows that there can be unexpected finds in Voyager images. That's not so important when we have Cassini images, but what about places where we don't have great images and not much chance of getting better ones for a long time? We've seen a few moons of Uranus here, but what about Neptune's Triton, especially the side not seen closely. Or the other sides of Pluto and Charon? Tomorrow, something much more dramatic than Mimaldi. #Saturn #Voyager #Rhea

Let's have a look for Tirawa. Here is an image - actually a composite of a few frames of a multispectral sequence - showing the right part of Rhea. It's near a full phase, so not much topographic shading. The black arrows show the full outline of the Tirawa basin. But what about the white arrows? They outline another basin called Mimaldi (see yesterday's map with names). It wasn't noticed at the time of Voyager and I wasn't confident enough to argue for it. #Saturn #Voyager #Rhea

Here is the set of Voyager images of Saturn's moon Rhea. The blank square separates Voyager 1 images (top) from Voyager 2 images, just 6 of the latter. The closer images show lots of craters - wall to wall craters. That one crescent image of Rhea shows an arc of shadow which is something bigger, an impact basin which was named Tirawa. It's not easy to find in the other images but it is there. Is it alone? #Saturn #Voyager #Rhea