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Posted by: um3k Sep 7 2005, 03:03 PM

Here are all the images from Cassini's recent Pandora encounter:
http://saturn.jpl.nasa.gov/multimedia/images/raw/raw-images-details.cfm?feiImageID=49038 http://saturn.jpl.nasa.gov/multimedia/images/raw/raw-images-details.cfm?feiImageID=49039 http://saturn.jpl.nasa.gov/multimedia/images/raw/raw-images-details.cfm?feiImageID=49040 http://saturn.jpl.nasa.gov/multimedia/images/raw/raw-images-details.cfm?feiImageID=49041 http://saturn.jpl.nasa.gov/multimedia/images/raw/raw-images-details.cfm?feiImageID=49044

http://saturn.jpl.nasa.gov/multimedia/images/raw/raw-images-details.cfm?feiImageID=49045 http://saturn.jpl.nasa.gov/multimedia/images/raw/raw-images-details.cfm?feiImageID=49046 http://saturn.jpl.nasa.gov/multimedia/images/raw/raw-images-details.cfm?feiImageID=49047 http://saturn.jpl.nasa.gov/multimedia/images/raw/raw-images-details.cfm?feiImageID=49048 http://saturn.jpl.nasa.gov/multimedia/images/raw/raw-images-details.cfm?feiImageID=49049

(final 5 images in next post)

Posted by: um3k Sep 7 2005, 03:06 PM

(continued from previous post)

http://saturn.jpl.nasa.gov/multimedia/images/raw/raw-images-details.cfm?feiImageID=49050 http://saturn.jpl.nasa.gov/multimedia/images/raw/raw-images-details.cfm?feiImageID=49051 http://saturn.jpl.nasa.gov/multimedia/images/raw/raw-images-details.cfm?feiImageID=49052 http://saturn.jpl.nasa.gov/multimedia/images/raw/raw-images-details.cfm?feiImageID=49053 http://saturn.jpl.nasa.gov/multimedia/images/raw/raw-images-details.cfm?feiImageID=49054

I'll post a color image soon, if someone else doesn't beat me to it.

Pandora is a very strange place, indeed.

Posted by: um3k Sep 7 2005, 03:42 PM

Here's color (IR3, UV3, P0+GRN; top left), as well as a 3d anaglyph (top right) and a cross-eyed stereo pair (bottom).
JPEG (low quality, fast download):

PNG (high quality, slow download):

Posted by: dvandorn Sep 7 2005, 07:22 PM

Is it just me, or do most of the craters on Pandora seem to be in advanced states of erosional degradation?

Also, there is a highly interesting pattern of radial spokes within the crater roughly midway between "top" and "bottom" in thiese images, about a quarter of the width of the images to the right of the terminator.

-the other Doug

Posted by: volcanopele Sep 7 2005, 07:46 PM

Probably not erosion. I suspect that dust from the F-ring has mantled the surface, giving it an overall muted appearance, by shallowing smaller craters and covering over the smallest craters.

Posted by: dilo Sep 8 2005, 10:55 PM

um3k, I had same idea about producing false color (IR3, UV3, GRN) image, then an enhanced color version (lot of work to minimize cosmic rays tracks):

Posted by: um3k Sep 9 2005, 02:00 AM

Very cool! I've made a super-res image, I'll upload it soon. It is made of three images, I can't do more than that due to motion issues. I didn't do much cosmic ray removal, either. But it's still pretty decent.

Posted by: um3k Sep 9 2005, 02:24 AM

Here's that superres I promised you:

Posted by: tedstryk Sep 9 2005, 03:05 AM

Nice work! I can't wait to see what that will do when we have raw data to use!

Posted by: dilo Sep 10 2005, 08:54 AM

Interesting!... is it possible to remove jpeg artifacts in order to better see details?

Posted by: Decepticon Sep 10 2005, 11:57 AM

Lots of topics on google...

http://www.google.ca/search?hl=en&rls=GGLG,GGLG:2005-25,GGLG:en&q=removing+jpeg+artifacts&spell=1

Posted by: Phil Stooke Sep 13 2005, 11:50 AM

um3k's super-res pic is very nice... I hadn't noticed the set of grooves near the terminator before (I'm only geting very brief glimpses of things). I'm very fond of grooves.

Phil

Posted by: um3k Sep 13 2005, 02:54 PM

Thank you for your compliments, everyone! I think I might do a rotation movie later today.

Posted by: um3k Sep 13 2005, 10:40 PM

Here's that rotation movie I promised:

Sorry, no noise reduction.

Posted by: dilo Sep 15 2005, 05:05 AM

Finally, thanks to um3k animantion, I was able to do make 3D Pandora images:
anaglyph:

crossed eyes:
Imperfections are due to slight illumination change...

Posted by: BruceMoomaw Sep 15 2005, 06:05 AM

Those grooves make it look even more like Phobos. By the way, http://www.lpi.usra.edu/meetings/lpsc2005/pdf/1186.pdf suggests that the grooves on Phobos are not crackes in its actual structure produced by the Stickney impact, but are instead tracks plowed in the regolith by big ejecta blocks from Stickney as they bounced and rolled across the surface.

Posted by: Toma B Nov 16 2005, 02:32 PM

Finally there is oficial image of Pandora on Cassini main page...
Nice!!!



Cassini's best close-up view of Saturn's F ring shepherd moon, Pandora, shows that this small ring-moon is coated in fine dust-sized icy material.

Craters formed on this object by impacts appear to be covered by debris, a process that probably happens rapidly in a geologic sense. The grooves and small ridges on Pandora (84 kilometers, or 52 miles across) suggest that fractures affect the overlying smooth material.

The crisp craters on another Saturn moon, Hyperion, provide a contrasting example of craters on a small object (see PIA07740).

Cassini acquired infrared, green and ultraviolet images on Sept. 5, 2005, which were combined to create this false-color view. The image was taken with the Cassini spacecraft narrow-angle camera at a distance of approximately 52,000 kilometers (32,000 miles) from Pandora and at a Sun-Pandora-spacecraft, or phase, angle of 54 degrees. Resolution in the original image was about 300 meters (1,000 feet) per pixel. The image has been magnified by a factor of two to aid visibility.

Posted by: Phil Stooke Nov 16 2005, 02:55 PM

Bruce commented (some time ago) on a suggestion that the grooves on Phobos may be caused by ejecta from its big crater stickney rather than as surface expressions of deep fractures.

This reference:

http://sci.esa.int/science-e/www/object/doc.cfm?fobjectid=36756

suggests that Mars basin ejecta did the deed instead. Personally (IM not-so-H O) I think Murray does a better job than Wilson and Head of making the case for ejecta. I prefer a fracture explanation myself, and I have suggested previously that the fractures responsible may be more like terrestrial jointing, produced by relaxation after excavation from a parent body. At any rate, fractures or ejecta, the tie to Stickney is very dubious.

This dispute is why I have a particular interest in scrutinizing small bodies for evidence of grooves. It's nice to see a few on Pandora.

Phil