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Posted by: SigurRosFan Sep 14 2005, 08:38 AM

http://photojournal.jpl.nasa.gov/catalog/PIA07732

Informatively image release.

Posted by: edstrick Sep 14 2005, 08:48 AM

Ooo.. Perfect time for a new thread... I was looking for a topic to attache the following to....

I ran my nifty-keano bandpass filtering enhancement on the mosaic today and got the attached results.

That previously discussed dark plume-like feature is still there. I will be most interested to know if it's changed in any way since the discovery images last winter or spring. The dark spot that seems to be it's source is featureless and lacks sharp edges at this resolution and signal-to-noise-ratio. The less well defined dark plume'ish feature at the top of the image also needs comparison with previous imagery. I will be even-more-than-most-interested to see of VIMS shows any spectral difference between these features and the normal dark materials seen at low lattitudes.

Also of interest, almost due south of the dark "plume" on the light-dark region boundary is about 2/3 of an almost perfect circle with a very slightly bright rim (I don't think artifact of the enhancement). The north edge and a bigger chunk of the south edge are disrupted by mostly light material. A smaller near perfect circle with some attached light "blobs" is visible to it's left, mostly surrounded by dark materials. Calderas? Eruptive Centers?... Impact Craters?.. They're quite different from the crater on the right side of the mosaic.

There really do seem to be low contrast streamers of lighter and darker albedo markings in the dark regions of the "H", but they're really at the S/N limits of the image.

Posted by: dvandorn Sep 14 2005, 09:07 AM

You will also note, very much evident in your enhancement and, I believe, a real feature -- a large circular feature that the last small bright circle you mention lies within. The boundary between the light and dark terrain directly to the north, and to the northwest especially, of that bright crater-like circle describes the upper third of a larger circular feature. That feature continues into the dark terrain as a series of darker arcs that are near-continuous with the arc above, forming the largest circular feature in the entire image.

Basin? Huge caldera? Volcanic collapse feature?

-the other Doug

Posted by: edstrick Sep 14 2005, 09:19 AM

DVandorn:

You are right. I did not see that at all, either the bay, or the dark features out in the dark region, add up to another circle.

I've "decorated" the enhancement with my two features and yours marked with radial red lines, and then went slighty crazy suggesting possible more circularoids (new geologic term) in the right part of the mosaic.

Posted by: SigurRosFan Sep 14 2005, 10:01 AM

More impact craters? Dark spots encircled by bright material.

Posted by: volcanopele Sep 14 2005, 05:50 PM

SigurRosFan, you're very welcome.

In terms of those dark streaks, Omacatl Macula and Elpis Macula, guess what I am doing my senior thesis and a paper on So, I am on the case

Posted by: volcanopele Sep 14 2005, 06:07 PM

Interesting work. Not sure I am convinced on some of the "circularoids", particularly some of those at the limits of the S/N. I'd really have to see those in more than one mosaic to be convinced they are there. The one at the bottom, edstrick, is Coats Facula, a feature we have interpreted as being tectonic.

SigurRosFan, the two circular features you point out are a little more convincing, certainly because we have seen those more than once. The one at left certainly seems to me to be a possible impact crater, not unlike the 80-km crater to its southeast. The other feature you point out is more interesting. actually, we have RADAR SAR data right over that spot:

Posted by: Sunspot Sep 14 2005, 07:05 PM

Volcanopele, do you have any more information on whether they managd to retrieve some of the radar data?

Posted by: volcanopele Sep 14 2005, 08:23 PM

They did, and it is spectacular

Posted by: edstrick Sep 14 2005, 08:27 PM

Volcanopele: ..." Not sure I am convinced on some of the "circularoids"....

Neither am I... those last examples are more than a bit "iffy". Enough beers, joints, late-night-fatigue, or Hoaglanditis can make you see ANYTHING!

I just wish real mid-infrared CCD-equivalent detectors more than 16x16 pixels or whatever had existed when Cassini was being designed. We have'm now but not then. VIMS atmosphere transparency and Imaging System resolution, ghods it would be easier.

Posted by: alan Sep 15 2005, 02:50 PM

I know that feeling, I've looked at the global map late at night and convinced myself that if I treated the dark areas as oceans I could slide the light areas together like pieces of a puzzle.

Posted by: tfisher Sep 15 2005, 05:35 PM

The last time Cassini got a good view of this region, the Planetary society page had an awesome science article including both radar and VIMS imagery. Check it out http://www.planetary.org/news/2005/cassini_titan05_results_0504.html

So who will be the first to give a blink image comparing the new and old views?

Posted by: Sunspot Sep 16 2005, 12:00 PM

Anddid they find any lakes ?

Posted by: Marz Sep 16 2005, 03:57 PM

I've not seen any mention of lakes yet, and they still put the word "islands" in quotes.

I saw this description in the Cassini Update newsletter:
"Tuesday, September 13 (DOY 256):

A significant amount of science data was lost during the recent Titan flyby as a result of an operational problem at the DSN tracking station, and a software error on the spacecraft. The software error was the larger contributor of the two causes, and the data loss resulted from an improperly set flag preventing the spacecraft from writing to or reading from the A side of the solid state recorder, so the result was performing the encounter with only half of the expected data storage volume. Commands will be sent on September 15 to reset the flag to its proper value, and normal operation is expected after this. The nature of the code error is now fully understood and has been reproduced in the spacecraft test bed. A decision will be made in the near future whether to correct the flight code or to implement workarounds to prevent the conditions that led to execution of the faulty code."

Posted by: Jeff7 Sep 16 2005, 04:29 PM

Doh! Sounds like NASA's probes need better debugging. Spirit was really out of it for a little while early in the mission due to a programming bug, and now Cassini's having issues.

Posted by: um3k Sep 16 2005, 04:32 PM

As long as humans are involved in the space program, there will be errors.

Posted by: mike Sep 16 2005, 05:18 PM

Yeah, I have to say, all code is perfect until it doesn't work. Software is complex, and generally speaking a bug will make everything fail. Mechanical devices have a bit of tolerance.. That said, once software is bug free it will work forever (as long as something doesn't corrupt the code itself, like a blunt object or a stray elementary particle..).

Frankly whenever I write any sort of complex code and it works immediately, I get worried.. There are ALWAYS bugs, it's just that some of them are more difficult to discover.

Posted by: volcanopele Sep 16 2005, 06:04 PM

We put "islands" in quotes so as not to have people think these are small areas of land surrounded by liquid. We use "islands" and "coasts" metaphorically, only because I really lack the imagination to really call them anything different well, they are surrounded by a sea of sand dunes I guess

I'm not really at liberty to discuss what is on the swath other than to say it is spectacular.

Posted by: Sunspot Sep 16 2005, 06:08 PM

........sounds interesting

Wasn't the first half of the radar pass over a more interesting geological region the the seond part which was lost?

Posted by: volcanopele Sep 16 2005, 06:25 PM

I couldn't really say. Our best images show the first half of the swath and our best resolution for the second half is 35 km/pixel. So there could be interesting features in the second half, but we just don't have the resolution to say for sure.

Posted by: volcanopele Sep 16 2005, 09:40 PM

Now I can talk:

http://photojournal.jpl.nasa.gov/catalog/PIA03563

Mezzoramia now looks like it is now or was at one time, covered by liquids.

Posted by: OWW Sep 16 2005, 10:41 PM

Pasted together two of the three images. The channels look spectacular! I Don't know how far to the right the third picture is supposed to be though...

Btw, how much of the RADAR-data was retrieved in the end?

Posted by: SigurRosFan Sep 17 2005, 07:59 AM

New radar images up at Photojournal.

http://photojournal.jpl.nasa.gov/catalog/PIA03565 (Titan's Rain Drains to the Plains)

http://photojournal.jpl.nasa.gov/catalog/PIA03564 (Canyonlands of Titan)

http://photojournal.jpl.nasa.gov/catalog/PIA03563 (Shoreline on Titan?)

New article: Cassini radar show dramatic shoreline on Titan

http://spaceflightnow.com/cassini/050916titanshoreline.html

Posted by: OWW Sep 17 2005, 08:07 AM

Sorry to see your blog go. I really enjoyed it. But are TPTB coming after your posts on forums as well? That would be very sad if that's the case. As I recall you didn't say anything 'secret' in your last post. Is JPL so concerned with image that absolutely no word of 'lost data' is allowed to come out?

Posted by: Decepticon Sep 17 2005, 10:50 AM

I once brought up this idea before along with other posters.

Why don't the cassini team dedicate a future flyby to just radar mapping?

Posted by: Decepticon Sep 17 2005, 11:13 AM

My location guess at part of the radar mapping.

Posted by: SigurRosFan Sep 17 2005, 12:39 PM

Difficult to say, Deception.

--- The next radar pass will be Oct. 26 when the team will focus on the Huygens probe landing site close to the equator. ---

I am looking forward to pinpoint better the landing site.