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Unmanned Spaceflight.com _ Cassini's ongoing mission and raw images _ Photo-journal Moon Map Updates!

Posted by: Decepticon Dec 30 2005, 12:54 AM

I was surprised to see these up. I just stumbled upon them.
Note: Some need major updates, But still nice to see.

Gotta love those Impact Basins!!

Tethys (You can see another Impact Basin in the southern Hemisphere) http://photojournal.jpl.nasa.gov/catalog/PIA07781

Rhea http://photojournal.jpl.nasa.gov/catalog/PIA07780

Mimas http://photojournal.jpl.nasa.gov/catalog/PIA07779

Iapetus Wow Great work here! COOL! Night side mapping!!

http://photojournal.jpl.nasa.gov/catalog/PIA07778

Enceladus So small yet So exciting! http://photojournal.jpl.nasa.gov/catalog/PIA07777

Dione http://photojournal.jpl.nasa.gov/catalog/PIA07776

Phoebe!!!!!!!! http://photojournal.jpl.nasa.gov/catalog/PIA07775

Posted by: Decepticon Dec 30 2005, 01:02 AM

And no new Titan Map.

Posted by: scalbers Dec 30 2005, 04:14 PM

Yes, I also spotted these yesterday, on the CICLOPS page. Interesting to start comparing with the maps I've been working on. For example, as you allude to, there is some good coverage from the Iapetus nighttime imagery (particularly south of the Snowman craters). I wonder if there are any good quality raw images available showing that?

Posted by: David Dec 30 2005, 07:26 PM

I hadn't noticed this before -- but on the Iapetus map, there's shown a smaller basin within the Really Big Basin, on the western side just north of the equator (at about 35° W). The floor of the northeast quadrant of this smaller basin (and adjoining areas) is very smooth (on this scale anyway), which is bizarre considering how beat-up the rest of Iapetus is. Why? Any ideas?

Posted by: JRehling Dec 30 2005, 07:32 PM

QUOTE (David @ Dec 30 2005, 11:26 AM)

Check out the closeup:

http://photojournal.jpl.nasa.gov/jpegMod/PIA06171_modest.jpg

Obviously, a landslide has led to a rough/chaotic surface inside part of the crater. The other part is quite smooth: some sort of flow has filled it in. Perhaps impact melt, perhaps cryovolcanism? It is smooth, but not utterly smooth...

Posted by: alan Dec 30 2005, 07:41 PM

The landslide crater was discussed here
http://www.lpi.usra.edu/meetings/lpsc2005/pdf/2268.pdf

QUOTE

Landslide crater. A 120 km-sized crater is located at the southwestern edge within the 550-km basin [1] at ~5°N/35°W. Almost half of its floor is covered by a giant landslide, which appears to have originated from the wall of the giant basin which is ~15 km high and has a very steep slope of at least 45°. Unfortunately, large parts of the wall lie in shadow so that no detailed structure can be seen. However, an area immediately adjacent to the crater on its northern side is also covered by the landslide. As in the crater, this area is rather sparsely cratered. A second curiosity of the landslide crater is that the crater floor shows no impact craters, but is very flat. Since the landslide crater itself is quite large, and because the landslide itself is covered by a few craters, it appears more likely that it has been resurfaced rather than being a very recent impact. Possibly, a relaxation of a locally weak ground removed all topography. Alternatively, deposits of fine materials might be considered, although the reason for this very localized appearance is not clear in either cases. Interestingly, the dark material coverage on the landslide and on the crater floor do not look different from each other or from other locations. This suggests that the process causingthe dark blanket ended later than the flattening of the crater -- perhaps even ongoing today.

Posted by: Michael Capobianco Dec 30 2005, 10:16 PM

It certainly looks like a cryovolcanic flow, doesn't it? But there don't seem to be any other similar circular cryovolcanic eruptions on the other icemoons, even Eneceladus. One explanation I heard involved a deposit of fine dust spread out from the landslide to cover the floor of the crater. Just one more Iapetus mystery to solve.

Michael