The latest in the poster series includes global perspectives of Dione up through the late April pass. Note the very similar views in the upper right, taken 6 June and 2 August 2005 respectively. DEMs of this hemisphere have already been produced. Natural color images (last in top row and first in 2nd row) by ugordan.



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Nice work!

One can really see the benefit of color imaging at Dione.

Alternate history:

The twister dumps Dorothy's house on the surface of Dione instead of Oz. She walks to the door with Toto in her arms. In addition to both of their lungs explosively decompressing in the near vacuum, the scene looks uninspiring in glorious color. Motion pictures remain in black and white for much of the remainder of the century.

Are these DEMs available anywhere on the WWW? Or only as crude color coded images in PDF files (abstracts/papers)?

Unfortunately, the ones available on the web are all of the color-coded variety for the time being. I've attempted to round them up here for one stop shopping...even with the low resolutions they are very instructive. The depth of the "snowman" crater complex on Iapetus is impressive.

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EDIT: Elevation scales on top center models corrected to +/- 5km

Compliled?

Seriously, that is a very cool way of showing these moons.

I was wondering if that sounded goofy. I was thinking compilation in terms of an album...composted, confused, or cannibalized might be more appropriate.

Exploitcorporations,
Image Vulture

Actually, I think he was pointing out the spelling error there

And giving nightmares to children everywhere.

Yeesh. My noise-to-signal ratio is rising with each post.

Exploitcorporations,
UMSF Spelling Bee Champion

quite the opposite!

Dione has a couple of pretty deep ones, too, which is perhaps not too surprising given the existence of the canyons. What's weird from EC's comparative montage is how very different Iapetus is in "texture" with respect to the other icy moons. Iapetus overall looks sort of like a partially melted/rapidly cooled ball of wax...

Yes, of course.
Click to view attachment
Snowman B and C look like imprints in sludge.
There seems to be no bowl shaped crater bottom inside them...
like they were filled up and faltened with some kind of partially melted/rapidly cooled material.
There isn't even a rim visible between B and C like the rim between A and B.

A final interpretation due to low resolution is difficult - and a close fly-by by CASSINI over the 'Snowman' will most
probably not happen.
Maybe september's saturnshine images will give some more infos - but certainly with low contrast!

Bye.

Good observations, TA.

Makes me wonder if maybe Iapetus has a much higher fraction of organics in its crustal composition than the other icy moons. Something seems different about the surface's melt/freeze point behavior given the odd geometry of the craters. Alternatively (or, for that matter, possibly additionally), could there have been a significant global heating event after the 'Snowman' and other major impact features were formed, such as tidal heating from orbital braking due to capture by Saturn?

Shooting from the hip, here: Iapetus seems more and more like an outer-system body out of place instead of a "native" Saturnian moon...NH may provide some interesting cross-reference data in 2015.

Admins, sorry for the OT excursion, but EC's montage rightly stimulates this line of discussion; please feel free to move to a suitable Iapetus thread!

Seven images of Dione in transet of ??? Who knows the object?

I've just noticed this myself - odds are against it being a new object I suppose.
Looking on the solar system simulator, it appears that Tethys' trailing co-orbital Calypso may be in about the right place......

Oh dear, getting a bit excited..... ugordan is right, it IS a star, an occultation to check for a tenuous Dionean atmosphere according to CICLOPS.

Animation of the Dione occultation event attached. Resized to 512x512. size=152k