Thanks for correcting me on the orbital diagram, and posting much better diagrams.
The ion drive is low thrust, so I'm guessing it'll start decelerating right were it says "new approach trajectory" in the upper left, or somewhere a little further long, like around the 24th.
Very cool !
the grimy crust over the mantle does seem to be fairly thin, a couple of people have pointed to the "ghostly" outlines of a large impact crater on one side, as if the crust is thin enough for markings to subside and disappear with time.
Yes, it will be interesting to see if there are any large impactor traces once we see a full spherical map, or it will be a fairly evenly spaced smattering of tiny, small and medium sized craters.
Some more thoughts:
Composition: Ceres is BIG ... far more than big enough to crush itself into a proper sphere under its own mass, even if all the material that it formed from was a mix of dust, silicates, rock, metallic asteroid fragments, yadda yadda, and some frozen gasses and dirty snow. As the sheer mass of all that compacts under its own weight, plus several billion years of additional gradual accretion, any solidified gas/liquid residues and water ice that might have been present would have long since been squeezed out towards the surface, and slowly sublimed/ionized away by the solar wind, leaving a dead cold core of mixed solid matter and dust, which eons of compaction would slowly turn into rock. Any remaining icy material would be limited to the outermost layers. Doesnt seem cold enough to be able to hold on to some of the colder gaseous materials we see out on Titan or the ice giants, so those have likely long since sublimed away well. What sort of ice is left depends on the thermal readings. I think I read somewhere that the Herschel readings didnt show enough water vapor to account for much, so that would seem to lean towards CO2, which could have degassed from comets travelling further inward.
I'm also saying a big fat NO to cryovolcanos. Yes, yes and maybe on ice moons like Enceladus, Titan and Europa, but
no friggin way on someplace much closer sunwards Ceres, which has neither tidal flexion nor a molten core to keep rhythmic state changes going. No no no no NO. Yeah, sure ... perhaps there's some radioactives present somewhere deeper inside, but ceres doesnt have enough mass for all those materials to melt and stratify, so even if present, itll be a buckshot mess that's probably not compact enough to generate meaningful heat over a large enough area to matter. Did I say no already ? Yes I did ... No crovolcanos.
I'm not a planetary geologist, that's just my own speculation.