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Posted by: Decepticon May 13 2006, 05:12 PM

Can someone point me in the right direction to any full Radar Swath releases.

For some unknown reason I can't find mine on my PC.


Thanks.

Posted by: volcanopele May 13 2006, 07:37 PM

only the Ta and T3 SAR swaths have been publically released, through the PDS. If someone asks nicely, I might convert what is in the PDS to a more easily readable JPEG format. The other swaths have not been publically released in full, except for those small size versions posted in the photojournal a few weeks ago. A large chunk (~50%) of the T8 swath was released on the Photojournal yesterday, though.

Posted by: Decepticon May 14 2006, 01:49 AM

Pretty Please!

Posted by: BruceMoomaw May 14 2006, 03:08 AM

With sugar on it. (Fructose, since that's healthier.)

Posted by: Decepticon May 14 2006, 03:13 AM

With Ustrax on it!:P

Posted by: peter59 May 14 2006, 06:36 PM

I have Ta and T3 Swath, but I can't publish it here, because I'm
not sure whether it is legal or illegal. So I present only thumbnails.



You can download Radar Swath from PDS archive. http://pdsimg.jpl.nasa.gov/forms/
You must download it on your computer, unzip it and use NasaView
program.

Warning:
These files are very large ( 335MB in orginal size 26368 X 4096).

I suggest download file BIBQF48N071_D035_T00A_V01.ZIP
(only 0,3MB in size 3296 X 512)

Posted by: angel1801 May 14 2006, 06:58 PM

I'm sure that any downloading of any space imagary based products are legal. NASA even states that almost (99.9%) all images are "Copyright Free" for personal and scientific use.

Posted by: tedstryk May 14 2006, 08:51 PM

If you downloaded it from the PDS, it is definitely legal. If it was given to you by the scientists, I would say it is still legal but immoral, as it would be a betrayal of trust.

Posted by: Bob Shaw May 14 2006, 08:57 PM

That's the nail struck squarely upon the head!

Bob Shaw

Posted by: BruceMoomaw May 14 2006, 10:25 PM

TA Swath, at least, is definitely publicly available on one of the LPSC abstracts, and T3 Swath MAY be publicly available. I'll *very heavy sigh* go through my records to try to find them...

Posted by: BruceMoomaw May 14 2006, 11:37 PM

Well -- although I imagine this is where Jason got his thumbnails -- you can find TA on both http://www.lpi.usra.edu/meetings/lpsc2005/pdf/2294.pdf and http://sci.esa.int/science-e/www/object/index.cfm?fobjectid=37161 , and T3 on http://www.lpi.usra.edu/meetings/lpsc2006/pdf/1497.pdf , all in highly enlargable form. As for the others, there's a lot available on the Nov. 2005 CHARM presentation ( http://saturn.jpl.nasa.gov/multimedia/products/pdfs/20051129_CHARM_RADAR.pdf ), with extensive notes.

Posted by: volcanopele May 14 2006, 11:45 PM

LPSC abstracts aside, the entirety of the Ta and T3 swaths are freely and publically available, and can be posted in JPEG format on this site. If peter59 doesn't do so before me, I will post jpeg version of swaths in the PDS tomorrow, at either 128 or 256 pixels/deg. It is the other swaths (T7, T8, and T13) where you would have at the very least ethical issues that I am not sure Doug wants to deal with.

There are some neat stuff there, though the Ta swath is probably my least favorite of the five returned thus far. Outside of the cutouts posted in the Photojournal (like of the Sisi's cat "lake", Ganesa Macula, and near flows and what not), the Ta swath is pretty bland. The T3 swath is much more interesting with two impact craters, Omacatl Macula, channels, mountains (though far fewer than in T13 and T8), and dunes.

Posted by: alan May 15 2006, 12:56 AM

T3SAR downsized from 17000 x 2200 to fit under 1MB.

Posted by: volcanopele May 15 2006, 07:04 PM

Moved discussion of Ta and T3 radar swaths, and radar swath availablity to its own thread.

JPEG versions of the PDS released Ta and T3 radar swaths are now up:

http://pirlwww.lpl.arizona.edu/~perry/RADAR/

Posted by: Decepticon May 15 2006, 11:07 PM

Excellent!

Posted by: edstrick May 16 2006, 09:37 AM

The first two titan radar passes were posted in quite high resolution on

http://www.stanford.edu/group/radar/

and the links are still there, but sometime in the last year, you get "Object Not Found" when clicking the link.

Posted by: Thorsten May 16 2006, 04:40 PM

Great stuff, thanks a lot!

By the way, is Omacatl Macula this strange dark splotch between the "Dark Terrain" (PIA07367) and the northern "coastline" of Fensal?

Posted by: volcanopele May 16 2006, 04:52 PM

that is fact Omacatl. I really need to go back to that guy...

Posted by: elakdawalla May 23 2006, 01:25 AM

By the way, I've posted a page with the full swaths (thanks, Jason, for retrieving those from the PDS for us all) -- as well as my attempts to reconstruct the patches of the swaths that haven't been fully released yet -- http://www.planetary.org/explore/topics/saturn/titan_radar.html. I also got a list of future SAR passes from a friend and posted it at the bottom of the page. I hadn't seen that list anywhere on the Web before so I thought it might be useful. Here it is, for the curious:

Future flybys that are currently planned to include SAR imaging:
T16 (July 22, 2006)
T17 (September 7, 2006) - ride-along (with INMS), possibly at less than optimal attitude
T18 (September 23, 2006) - ride-along (with INMS), possibly at less than optimal attitude
T19 (October 9, 2006)
T21 (December 12, 2006)- ride-along (with INMS), possibly at less than optimal attitude
T23 (January 13, 2007)
T25 (February 22, 2007)
T28 (April 10, 2007)
T29 (April 26, 2007)
T30 (May 12, 2007)
T39 (December 20, 2007)
T41 (February 22, 2008)
T43 (May 12, 2008)
T44 (May 28, 2008) - maybe; the planners are carrying two options, one of them SAR.

A little story about the Ta and T3 swaths -- I downloaded them from that Stanford website when Jason posted about their availability in his blog, and re-posted them on the Society's old website. They were still available on the old pages when we switched to our new site design last October, but I hadn't yet ported them over to the new site. Then, in December, I got an email from a RADAR team member, asking me how I'd come by them, because a paper had appeared by some in press by some non-Cassini scientists analyzing some of the data, which was not yet released to the PDS. (Jason talked about that http://www.unmannedspaceflight.com/index.php?showtopic=1872.) It seems that in the interim, the RADAR team had shut down the "leak" from Stanford (from a team member who apparently didn't understand the data release process), but hadn't known that I'd reposted them...oops. I hadn't meant to contribute to that bit of uncool scientific behavior. Fortunately the RADAR team didn't cast any blame on me for the incident; they were quite nice about it, actually. At the RADAR team's request I removed the images from the old website last December -- but since they appeared in the PDS in January it was safe for me to put them back up.

--Emily

Posted by: Decepticon May 23 2006, 12:29 PM

Emily You ROCK!

Posted by: Thorsten May 23 2006, 01:42 PM

Wow! Thanks a lot, Emily!

BTW, I’m not sure if this is helpful for you, but in one of the Titan vision studies from the October 6–7, 2005 OPAG Meeting (http://www.lpi.usra.edu/opag/oct_05_meeting/jpl_titan.pdf) there are two beautiful parts from – what I believe is – the T7 (Sept. 7, 2005) SAR radar swath. The image on Page 6 of the vision study is northwest (left) of PIA03564 (Canyonlands of Titan) and shows some mountainous/hilly region probably in Central Tsegihi. The region shown on Page 8 is between PIA03565 (Titan's Rain Drains to the Plains) and PIA03563 (Shoreline on Titan?). You can see the rivers of PIA03565 flowing into that strange RADAR bright stuff.
However I don’t know if it is illegal or immoral to post these parts of the T7 swath because they are actually not yet publically released. Hope, I’m not involved in any kind of scientific misconduct right now!

Posted by: elakdawalla May 23 2006, 03:30 PM

I don't think you have to worry, Thorsten; you can see that much of the swath from the various context images that the RADAR team has started releasing, for example:
http://photojournal.jpl.nasa.gov/catalog/PIA03571

Those context images were pretty useful in figuring out approximately where the press-released bits fall on each swath. I'm glad the RADAR team has started doing that, they're very helpful.

--Emily

Posted by: volcanopele May 23 2006, 05:24 PM

Your placement of the T13 releases is a little off. Check out my post from last week or so on the placement of the released crops in the swath:

http://www.unmannedspaceflight.com/index.php?s=&showtopic=2425&view=findpost&p=53445

Posted by: elakdawalla May 23 2006, 05:34 PM

Oops. Fixed. Thanks. --Emily

Posted by: BruceMoomaw May 24 2006, 03:59 PM

Believe me, Thorsten, if those swaths were shown in an OPAG presentation, they are public property and nobody will jump you for trying to fit them into context. (The managers of the COMPLEX meeting that I attended cheerfully mailed me, without a peep, hard copies of all the Powerpoint presentations shown -- including a huge one by Elizabeth Turtle packed with SAR views from the T8 swath that were publicly shown for the very first time at that meeting. Maybe it's time I looked at those again.)

One thing I'm starting to notice in recent scientific presentations is that bloggers are starting to get explicit credit from the scientists for their work in putting useful image mosaics together -- especially in the case of the Huygens images.

Posted by: The Messenger Jun 9 2006, 05:05 PM

This is probably already on the board somewhere, but I don't see it:

http://planetary.org/blog/
The official publication on the second Titan RADAR swath is out

Posted by: Tom Tamlyn Jun 9 2006, 05:52 PM

The permalink to Emily's post on the second Titan RADAR swath is http://www.planetary.org/blog/article/00000601/.
TTT

Posted by: volcanopele Jul 17 2006, 05:35 PM

I have added the T7 swath to my RADAR swath page:

http://pirlwww.lpl.arizona.edu/~perry/RADAR/

Unlike Alan, I used the BIFQI version of the file. From the looks of it, the pixel values range from 0.05 to 1.4 or so, so I am guessing in this product, the pixel values have been converted to dielectric constant or some RADAR equivalent to I/F, like I do with ISS images while the BIBQI version uses the actual brightness values. the "F" version may also be corrected for incidence angle (or emission angle or what ever...). I would ask our resident RADAR team member, but I'm not sure he is in town.

I should also point out that the file has been rotated 90 degrees CCW from what is in the PDS. Also, if anyone wants lat-lon gridded versions at 128 pixels/deg., let me know.

EDIT: If I looked in the label file, I would find my answer... "The data values in this file are Synthetic Aperture Radar (SAR) normalized backscatter cross-section values. The values are physical scale (not in dB) and have been corrected for incidence-angle effects. The raw backscatter values have been multiplied by the function f(I), where I is the incidence angle and f(I) = 1.4142*sin(I)."

Posted by: volcanopele Oct 6 2006, 08:18 PM

I will be posting the T8 swath, released on the PDS earlier this week, in a few hours. This swath is quite large (not to mention there is a seperate, short segment from that pass) so it will take a little bit.

Posted by: Decepticon Oct 7 2006, 06:27 AM

Soon?!

Posted by: peter59 Oct 7 2006, 10:07 AM

I have, I have, I have !!!

T8 swath

Posted by: volcanopele Oct 7 2006, 03:28 PM

Sorry, network was really slow yesterday. Too many people trying to download that Victoria crater image. I'll try to have the whole thing up this weekend.

Posted by: Decepticon Nov 6 2006, 07:38 PM

I tried at updating the Cassini RADAR coverage map. It's not 100% correct. Does look better with the area filled in.

Flyby T13 (Apr 30, 2006) Was added.

Posted by: JRehling Nov 6 2006, 10:26 PM

Cool. That's 4.5 swaths done. The total number of swaths by the end of the extended mission may be as high as 30 or so. At the end, we'll have a piecemeal map of strips and stripes that should be pretty representative of the globe, but annoyingly "gap"py.

Posted by: Decepticon Nov 12 2006, 04:55 AM

Are there 8 or 7 swaths still not added?

I'm not sure if one of the swath was lost?

Posted by: volcanopele Jan 9 2008, 10:52 PM

I've updated the Titan RADAR SAR swath page to include all the RADAR swaths released on the PDS (now through T25). I also included the ISS-RADAR map showing the coverage up to T25:

http://pirlwww.lpl.arizona.edu/~perry/RADAR/

Posted by: peter59 Jan 10 2008, 06:50 PM

What's with T29 ??

Posted by: volcanopele Jan 10 2008, 07:26 PM

I guess I forgot about it. Thanks for reminding me.

Posted by: JRehling Jan 10 2008, 07:50 PM

Great stuff. I know there's an imperfect correlation between IR and radar (and even radar from two different angles, or IR with different phase angles), but the cartographer in me wants to fuse all of this info into a one-wavelength-fits-all map with as broad of coverage as possible. Slap a layer of low-res color based on VIMS on top, and call it a global map. It's getting pretty complete now, but I guess we may as well wait for Cassini to finish its work before doing the backbreaking cartography. But I've still got my 6-inch globe of Earth waiting for a Titan skin to get gored and pasted on.

Posted by: Juramike Jan 10 2008, 09:01 PM

It looks like IR and RADAR are not very correlated at all. Even at it's simplest, this becomes a multi-dimensional problem. Titan is deserving of a map of multiple layers so you can capture the "deep" data.

The best thing might be three different maps:
-Relative Altitude (which I suspect is correlated with IR in the Equatorial Zones)
-RADAR
-VIMS

Or you could try to use a whole bunch of colors in the pallette to try and hit all the myriad combinations (example: the RADAR bright, but IR dim, VIMS dark blue = medium blue; while RADAR medium bright,but IR dim, and VIMS dark blue = darker blue). But this will get really complicated (although very pretty) on a global scale.

Do you have 3 globes you'd be willing to sacrifice?

-Mike

Posted by: Exploitcorporations Jan 11 2008, 02:44 AM

Thanks so much, VP!

Posted by: JTN Jan 16 2008, 01:15 AM

Thanks for this. I've put up http://www.chiark.greenend.org.uk/~jacobn/cassini/ of the new stuff. (I haven't bothered with the distant stuff since it's generally small enough to view directly.) Same caveats as http://www.unmannedspaceflight.com/index.php?showtopic=3745&view=findpost&p=82617.

Posted by: Juramike Jan 16 2008, 02:54 AM

Thank you both very much both VP and JTN,

I've been hitting your pages like a hummingbird hits a feeder.

-Mike

Posted by: volcanopele Aug 29 2008, 11:43 PM

The T28 and T29 RADAR swaths are now online in the PDS. I have added them to my RADAR SAR page and to the ISS-RADAR map:

http://pirlwww.lpl.arizona.edu/~perry/RADAR/

Posted by: Juramike Aug 30 2008, 03:31 AM

Thanks, VP!

-Mike

Posted by: TheChemist Aug 30 2008, 10:21 AM

Many thanks, VP, some nice coastal property there.
Could I point out that the link to the 2nd part of the 256 pixels/deg of the T29 swath should be corrected, currently it opens up the 1st part.
Cheers !

Posted by: volcanopele Aug 30 2008, 07:23 PM

Okay, I figured out what happened. Part 2 being uploaded.

Posted by: Sunspot Aug 30 2008, 07:39 PM

T30 - "Large Northern Sea" ???

Posted by: volcanopele Aug 30 2008, 07:51 PM

In that case, I mean Kraken Mare, and not the North Pole Sea.

Posted by: peter59 Oct 23 2008, 04:05 PM

The T30 RADAR swath is now online in the PDS. (22 Oct. 2008)

Little more (west edge) than image released by Photojournal.
http://photojournal.jpl.nasa.gov/catalog/PIA09218

Posted by: peter59 Oct 23 2008, 04:53 PM

Previously unseen region in greater resolution.

Posted by: ngunn Oct 23 2008, 09:14 PM

Thanks for posting those - truly spectacular. The dark channels within some of the islands look (at a superficial level) too wide to have been produced solely by drainage of rainmethane from such small areas. I wonder if lake tides flow in and out of them, making them more like estuaries?

Posted by: Juramike Oct 23 2008, 09:54 PM

Flooded deep valleys is another possibility.

Maybe there was a really dry and stormy period that carved out deep valleys, then they all got flooded during the latest climate cycle.
[/wild speculation]

-Mike

Posted by: tty Oct 24 2008, 05:57 PM

I agree with Juramike. They look very much like terran rias, i e river valleys flooded by a rising sea (or sinking land). They are common in the southeastern US (which slowly sinking) for example around Chesapeake Bay.

Posted by: imipak Oct 24 2008, 06:46 PM

The image reminded me strongly of http://maps.google.co.uk/?ie=UTF8&ll=50.293726,-4.529114&spn=0.594831,1.400757&t=k&z=10... there's also a resemblance to maps of snow-covered mountains, which has geometric similarities (a flat plane, the snowline, intersecting eroded peaks, with the distinction emphasised visually by the different appearance of snow and rock.) I know / understand very little about Titan and it's landforming processes, but presumably the fractal values of such landforms derive from a physical constants (the slope of the valleys, resistance to erosion, power of the eroding flows that form the valleys, a 'branching constant', etc.) Is the apparent visual similarity coincidental, or does it imply analogous processes / morphologies?

Posted by: ngunn Oct 24 2008, 09:30 PM

I agree that large sections of the lake shore look like drowned mountain topography, making the valleys rias. But those shorelines, and the terrestrial examples of rias cited, all have a large catchment areas upstream able to create large river valleys for later flooding. You can't do that on a small island, like the one at the rightmost extremity of the straggling archipelago in this Titan image. There also seem to be at least two cases of similar-looking channels cutting right through an 'island' from side to side, which I find somewhat suggestive of two-way flow. (Mike, you have previously identified such features on a bigger scale in the sand seas IIRC.) It's all guesses I know.

Posted by: Juramike Oct 25 2008, 04:37 AM

I think there might be three things coming together:

1) A tectonic ridge structure running left right across the Swath.
2) Possible almost orthogonal undulations or deep valleys cutting across the tectonic ridgeline
3) The entire structure indundated.

[And 4) a little crater on the archepeligo that got breached and the wall on the right side collapsed.]

Titan is unimodal: there is no evidence for tectonic subduction. But there can be gentle upwarping and downwarping. I wildly speculate that the north polar region has a broad downwarping. (Adiri and Xanadu, may have been subjected to ancient upwarping.).

I also speculate wildly that Titan may have had several climate shifts. There may have been an earlier period of extensive erosion in the North polar region, only to be followed by later indundation with the present climate.

[Other evidence for this? The fretted terrain of T18 and T39 may have been formed by erosion into earlier deposited materials. Uniform erosion across similarly friable materials would explain the observed pattern (just like fretted terrain on Mars)]

So this terrain may have had tectonic ridges and orthogonal undulations getting cut and eroded by an earlier stormy climate. It would have looked like a more-eroded version of Adiri. Then a broad regional downwarping could have drowned the mountains and broad valleys with sediment and lake fluids, giving the landscape we see today.

Being able to penetrate the murk and see what is in those gaps and beyond would be key to confirming this scenario. If this scenario is correct, we should see broad subsurface valleys extending out into the lakes, possibly hidden by sediments. Lake level changes should be evident along the up-down shoreline (shallow gradient of undulations) but less evident along the right-left tectonic ridges (steeper gradient.)

The main difference (I think) between the "archipeligo cuts" in this area vs. the reversible channel in T8 is that the T8 channel went in the direction of the EW tectonic ridges (cutting across a broad NS uplifted area and had an interesting RADAR gradient pattern at either end. In this area I think the "cuts" are parts of long deep valleys that would have a unidirectional gentle gradient.

Another possibility for this area would be glacial features that might've been pinned back by the tectonic ridge. But that idea is really off the top of my head. (Then you would expect to see an offshore morainal dump zone if you could magically penetrate the murk).

Looking at other shorelines near this region might also help elucidate what's going on. (Might get lucky and see some diagnostic features exposed and visible in SAR RADAR images of shallower regions)

Whatever formed this, it would be a really, really neat place to explore by kayak!

-Mike