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Posted by: slinted Jan 15 2005, 02:41 AM

Contrast enhanced triplets http://mars.lyle.org/titan/
raw triplets http://mars.lyle.org/titan/raw/

The 'stream' animation : http://www.mars.asu.edu/~gorelick/huygens1.gif

i've done a couple small mosaics, chock-full-o-jpeg artifacts:

3 frame from the high-res camera : http://www.lyle.org/~markoff/huygens/shoreline.jpg

4 frame from the medium-res camera : http://www.lyle.org/~markoff/huygens/shoreline_medres.jpg

The ones I did are pretty bad, but I figured people might find them interesting anyway. I'm sure we'll see much better in the next couple days.

Posted by: David Jan 15 2005, 03:27 AM

Okay, I have to admit it now; if those are rivers then what they're draining into must be a lake. Or... part of an ocean? In either case, that means there's a pretty high bank close to the shore (like the drainage of southern Lake Michigan, I suppose).

Posted by: gpurcell Jan 15 2005, 06:35 AM

I think people are misinterpreting the channels. They might look like they are flowing the wrong way, but they aren't. Rather, they're all coming off of a highland and flowing down to the sea.

For it is a sea. It must be.

Posted by: volcanopele Jan 15 2005, 06:59 AM

or it was a sea. landing site images from "The sea" show at best some trickling methane.

Posted by: remcook Jan 16 2005, 12:05 PM

niiiice

http://www.spaceflightnow.com/cassini/images/050115montage.jpg

http://sci.esa.int/science-e/www/object/index.cfm?fobjectid=36370

Posted by: djellison Jan 16 2005, 12:36 PM

It reminds me of one of those sea-side resorts that has a huge tidal reach - and when you get a veyr low tide - you have miles of damp sand - and occasionally - tiny little trickles run thru it.

The thing landed 2 miles west of Weston-Super-Mare !!

Doug

Posted by: Mongo Jan 16 2005, 03:12 PM

Yes. From the panorama linked to above, it appears that Huygens landed on one of the 'sand bars' or 'shoals' just 'offshore' from the 'mainland' (presence or absence of quote marks depending on the nature of the dark unit). In which case, the apparent signs of flowing liquid might not be due to a 'stream', but possibly due to the 'ocean' advancing/receding due to a tide.

ESA is saying that these 'shoals' are fog banks, but I am not convinced. They seem to have been unmoving and unchanging during the descent of Huygens, with only their visibility improving with lower altitude.

Bill

Posted by: SFJCody Jan 16 2005, 03:32 PM

Some more DISR mosaics are up at http://anthony.liekens.net/index.php/Main/Huygens

Including this one



We have to go back!

Posted by: Decepticon Jan 16 2005, 04:07 PM

WOW!

Can they do anything about the jpg distortions/compression?

Posted by: alan Jan 16 2005, 05:46 PM

Wow. I'm glad the raw images were leaked. Just imagine how long it would take for the ESA to release something like this.

Posted by: Sunspot Jan 16 2005, 06:09 PM

The RAW images have been re-posted now

http://www.lpl.arizona.edu/%7Ekholso/data.htm

Posted by: Mongo Jan 16 2005, 06:12 PM

There are yet more mosaics available at http://anthony.liekens.net/index.php/Main/Huygens. By far the most interesting to me is http://anthony.liekens.net/titan/bigmosaic2.jpg, which was taken at a higher altitude than http://anthony.liekens.net/titan/bigmosaic.jpg.

In it, you can clearly see 'land' on BOTH sides of the 'ocean'--which makes sense, given what we knew from the global imagery of the Huygens landing zone. What we are looking at is apparently a 'strait' or channel between two land masses.

He also has a http://anthony.liekens.net/titan/titan_panorama_colored.jpg version of http://anthony.liekens.net/titan/titan_panorama.jpg.

Bill

Posted by: chris Jan 16 2005, 06:12 PM

They have much better contrast than the previous ones we have seen. Has anyone published the correct order for the triplets yet?

Posted by: tedstryk Jan 16 2005, 06:43 PM

I wonder if they were taken down due to a bandwidth issue, or if ESA realized that the proverbial cat was already out of the bag so there was no point in having the official DISR site be the only Huygens site without the images!

Posted by: tedstryk Jan 16 2005, 09:37 PM

Here is a version of another surface image. I produced it from 127 images from the middle camera, and used the color from the released image.

Posted by: Mongo Jan 16 2005, 10:03 PM

Has anyone made an animated GIF from the middle-camera images taken on the surface, in a way similar to the animated GIF from the more familiar upper-camera images? If there is a fluid flowing over the patch of ground imaged by the middle camera after landing, we should see its effects through distortions of the images.

Also, that bright reflection on the lower right part of the images looks a lot like a specular reflection. It's similar to what you would see if you found a shallow (a few cm deep) stream with a rocky, sandy bottom, and shone a floodlight onto it.

Bill

Posted by: tedstryk Jan 16 2005, 10:19 PM

I would like to see that. My problem is that I am not quite sure what order the images should go in. The triplets don't seem sequential, unless I am looking at it wrong. It defintely does seem that the camera is dirty or had something splash on it.

Posted by: volcanopele Jan 17 2005, 02:51 AM

Attached is my attempt at a panorama. A bit crude, being in photoshop and all. And I wasn't trying to be 100% perfect, I don't get paid for this and those who are (and even a few amateurs out there) will do a better job. This is basically from triplet 380 to triplet 490 or so.

Posted by: Mongo Jan 17 2005, 04:06 AM

Another panorama by http://anthony.liekens.net/images/titan/huygens-join.jpg, similar to volcanopele's, is now up at the http://anthony.liekens.net/index.php/Main/Huygens. This one is not final; in Anthony's own words:

The main substantive difference between this one and volcanopele's, is that volcanopele's mosaic extends further in all directions, while Jakub's mosaic is a bit more complete within its boundaries.

Bill

Posted by: Sunspot Jan 17 2005, 04:13 PM

Another nice mosaic

http://spacenews.dancebeat.info/images/Huygens_Full_Landing_Site_Mosaic.jpg

Image credit: Kevin Dawson/SpaceCanada.org + other space enthusiasts
Original image credit: ESA/NASA/University of Arizona

Found on this site http://spacenews.dancebeat.info/index.php?topic=Cassini_Huygens

The much brighter white features seen inside the darker areas do have a superficial resembelance to some features seen in the radar images, particualrly the "arrow head" shaped areas.

Posted by: OWW Jan 17 2005, 09:53 PM

Official mosaic! :

http://www.esa.int/SPECIALS/Cassini-Huygens/SEMA6U71Y3E_1.html

Nice. Still has camera blemishes and JPEG artefacts though.

Posted by: SFJCody Jan 17 2005, 09:58 PM

And the so-called 'tiff' is actually a 'png'

Posted by: alan Jan 18 2005, 05:50 AM

I wonder if they are going to fix this
http://s04.imagehost.org/view.php?image=/1590/PIA07230duplicates.jpg
taken from here
http://photojournal.jpl.nasa.gov/catalog/PIA07230

Posted by: BruceMoomaw Jan 18 2005, 12:13 PM

Christian Waldvogel's already done a superb job of fixing it, Alan ( http://www.futura-sciences.com/communiquer/g/showphoto.php/photo/509/sort/1/size/big/cat/525/page/ ). The DISR folks themselves, did, I think, a mindbogglingly lousy job themselves, apparently thanks to their obsession with the idea that the vertical axes of all the individual frames had to be parallel -- which, to put it mildly, they were not in reality.

By the way, DISR imaging team head Bashar Rizk has just tossed another tidbit of information my way: contrary to what ESA says in its photo caption, the frames for that panorama were NOT all taken from the 8 km panorama -- thanks to the Channel A failure, they didn't get a completely panorama from ANY altitude, and this one had to be put together from "images from different pans". But I still haven't gotten any information from him on just how low-altitude the final pre-landing images were -- I may make a phone call to LPL tomorrow to look into this further. (Tomasko's document describing the DISR does say, however, that all its photos between 3 km and 200 meters altitude were sent back at 8-second intervals -- and since Huygens, by then dropping at 5 meters/second or a bit less, would have taken over 9 minutes to pass through that altitude range, I find it virtually impossible to believe that they didn't get a fair number of images from those altitudes back via Channel B.)

Posted by: OWW Jan 18 2005, 12:55 PM

According to this article 600 images were received:
http://www.planetary.org/news/2005/huygens_mosaic_0117.html

I quote:

It's been harder than expected for the Descent Imager Spectral Radiometer team to interpret their pictures, for two main reasons. One is the loss of one of the two communications channels from Huygens. The DISR instrument split its bandwidth between the two channels, so the loss of "Channel A" means that only half of the DISR images that were acquired were returned to Earth. The lost images are scattered randomly throughout the data set, so while images were acquired in triplets (one each from a side-looking, angled-down, and downward-pointing camera), the returned triplets are often missing one or two of the component frames.

The other difficulty for DISR arose from Titan's recalcitrant atmosphere. DISR contained a Sun Sensor that was designed to help the instrument identify which direction it was pointing relative to the Sun as the probe rotated. Unfortunately, early in the descent, the probe was swaying much more strongly than anticipated, and the Sun Sensor was unable to get a "lock" on the Sun's position. (The reason for the strong swaying is not yet known for sure, but one possible explanation is higher-than-expected horizontal wind shear.) And later in the descent, Titan's haze proved to be deeper than expected, so the Sun was too dim and diffuse for the Sun Sensor to detect it. As a result, DISR was less sure of its orientation while it was taking pictures than was expected.

Despite the communications trouble, DISR still acquired 600 images. The DISR team is now located at the European Space Operations Centre, and is working almost without sleep to process and calibrate the images to improve their quality, and then mosaic them together. Give them some time, and they will show you all that Huygens had to reveal of Titan's surface.

Not clear though if those 600 images are triplets or frames. And how many of those were taken during descent.

Posted by: BruceMoomaw Jan 18 2005, 03:06 PM

They're definitely referring to the total number of frames, not triplets. The plan from the start was to have Huygens take only about 200 triplets (plus about half a dozen individual HRI frames during the last few minutes of its descent), then about 80 more triplets during its first 10 minutes on the surface. That "700" figure we keep hearing for its originally planned number of total frames was a reference to the 605 or so frames it was to take during descent, plus whatever it could get if it survived for just a few minutes on the surface. The Channel A failure cut this in half, but its longer-term survival on the surface let it get a total of about 600 frames anyway, with about half of them being repeated shots of that same post-landing surface scene (taken at a reduced rate after the first 10 minutes, largely to look for any clouds that might happen to drift by).

Posted by: alan Jan 18 2005, 03:30 PM

Yes, his version looks much better but it still has the extra "island". This is where the "islands" should be:
http://s03.imagehost.org/0743/Berichtigtes_Huygens-Panorama.gif

Posted by: alan Jan 18 2005, 03:51 PM

ESA has a movie of the descent images with the altitude listed
http://www.esa.int/SPECIALS/Cassini-Huygens/SEM5YW71Y3E_1.html

Posted by: OWW Jan 18 2005, 04:43 PM

On the same page, ESA also posted a zip file with the press conference slides.

http://esamultimedia.esa.int/images/huygens_pr_15_jan.zip

It contains pdf files with the graphs from the radio astronomy, acp, disr, gcms and ssp.

Posted by: TheChemist Jan 18 2005, 05:42 PM

The GC-MS results must be from the atmospheric unit manifold (IS1). If the numbers 14,15,16 correspond to molecular weights I guess CH4 abudance is shown (amu 16).
Times have to be correlated with altitude. I 'll have to look it up more closely at home, along with the mision pdfs, later hopefully.

edited to correct MW errors shame on me

Posted by: Sunspot Jan 18 2005, 06:10 PM

Wow.....

You can see alot of what look to me like channels in the images located in the dark areas near to where Huygens landed...perhaps they landed in or very close to one.

Also, the image with the circle indicating the landing site looks much better than any i've seen before - fewer compression artefacts.

edit:

The title of the article is "Huygens lands in Titanian Mud" further down we have the caption "Landing with a Splat" but no further explanation.

Posted by: OWW Jan 18 2005, 08:36 PM

This article ( http://story.news.yahoo.com/news?tmpl=story&cid=624&ncid=624&e=1&u=/ap/20050118/ap_on_sc/europe_saturn ) claims Huygens landed "just a few yards from the shoreline".
Maybe that oval dark area is a small basin surrounded by icy ridges?

Posted by: djellison Jan 18 2005, 08:47 PM

FWIW - and I'm not a geologist...

I think we have a dark sandy material as the 'sea bed' - and ice/ice+organics as the 'mainland'. For some reason - be it tidal or wind of flow of some other reason- we have had 'bars' of deposits that might be carried down from the mainland out into this flood plain - these rounded ice-pebbles look a bit like terminal moraine and flood-debris.

Where do you see ridges and bars of rounded eroded debris off a 'mainland' feature

Doug

Posted by: BruceMoomaw Jan 19 2005, 02:55 AM

The AMUs shown in the graph of GCMS data, according to Sushil Atreya during the press conference, are for methane (AMU 16), the methyl radical (AMU 15), and doubly ionized atomic nitrogen (AMU 14). Presumably the very low counts for nitrogen (10 times lower than the methane count in that cloud layer!) are due to the fact that they represent only the small number of nitrogen atoms that the MS electron gun not only ionized but tore loose from their strongly bonded diatomic N2 molecules.

I'll add a bit more on the various released graphs later.

Posted by: BruceMoomaw Jan 19 2005, 06:19 AM

Here's some more on those new slides of graphs from the last press conference (including data from the few crumbs of verbal commentary added by the scientists):

(1) The two graphs of pressure and temperature vs. altitude from HASI are missing -- but there were no surprises. Surface pressure from HASI was almost exactly 1.5 bars. Atmospheric temperature dropped to only 70.5 K throughout the stratosphere (roughly 70 to 40 km), then rose to a surface temperature of 93.8 K., following just the shape of curve predicted.

(2) The graph from the SSP echo sounder is a more serious omission -- the only one shown, which shows virtually nothing, is just the last in an animated sequence of about a dozen echoes off the surface, taken at altitudes ranging from 100 m down to the surface. They were very strong -- rising, at the end, to a peak running almost to the top of the graph -- and they consistently showed something very interesting. Almost every one showed a clear DOUBLE spike -- with the second echo sometimes almost as strong as the first, and sometimes weaker -- and the time between the two peaks roughly the same at all altitudes (reflecting, I roughly estimate, a distance gap of about 10 meters, assuming that the speed of sound was the same in this layer as in the atmosphere). Could they have been picking up a second echo from a floor below the surface -- the depth of the mud layer?

(3) The GCMS graph shows, as I said, relative MS counting rates for doubly ionized atomic nitrogen (produced by the MS itself), methane, and the methyl radical. The nitrogen/methane ratio stayed constant all the way down to a layer at 20 to 18 km -- apparently a fairly dense cloud or haze layer -- where the CH4 mixing ratio suddenly took a leap of about tenfold. Then it dropped again just as sharply -- but from there down to the surface, the CH4 ratio stayed roughly twice as high as it had been above that apparent cloud layer. After landing, it rose again gradually, presumably as the heated inlet started boiling CH4 out of the "soil", and then finally levelled off at about 3 times higher than it had been just before landing.

(4) Tomasko's graph of the DLIS (Downward-Looking IR Spectrometer) surface spectrum obtained at 100 m altitude shows, as you can see, three peaks at the same places where peaks are expected for both water ice AND hydrocarbons. And while, in the longest-wavelength of those three peaks, hydrocarbons have a much higher reflectivity than ice, the reflectivity of Titan's actual surface was considerably lower than both ice AND hydrocarbons in all three bands. This suggests (as Tomasko said) that some other kind of darkening agent had been mixed in -- and, I imagine, also makes it impossible to judge the actual ice/hydrocarbon ratio of the surface from these bands. But in the longest wavelength zone, the reflectivity of hydrocarbons is once again much higher than that of water ice, and this time the graph from DLIS almost exactly follows the much lower curve for water ice (it is, perhaps, very slightly higher). This one clue suggests (as Tomasko again said) that, at least at that point on the surface, the surface was mostly water ice with little of the hydrocarbons that had been expected, but with some other as-yet unidentified darkening agent mixed in.

(5) Tomasko also noted that the DISR images show that, between 10 and 20 km altitude, Huygens was being blown sideways by a wind of about 7 meters/second.

Posted by: Sunspot Jan 20 2005, 01:04 AM

RAW Triplet 202:



Could those be raindrops on the camera lenses?

Posted by: LtlPhysics Jan 20 2005, 04:46 AM

Hi!

I found these a few days ago, but don't recall how. They are very very wide and may be dupes of each other.

http://www.its.caltech.edu/~rwald/pano567-nodupes.jpg

http://whodatzone.com/forum/index.php?act=Attach&type=post&id=714

Posted by: BruceMoomaw Jan 20 2005, 04:47 AM

I've wondered about that myself. You will notice that, throughout the later frames, there's a pattern of little round transparent circles (in the same places for each frame) that look exactly like little clear drops of liquid on the optical windows. I wouldn't be at all surprised to learn that the DISR got briefly rained on -- or hit from underneath with large methane cloud droplets -- on the way down.

Posted by: alan Jan 21 2005, 04:41 AM

The movie that was made up of descent images that is on the Planetary Society's site has the altitudes listed. If the altitudes listed are accurate then the mosiac that is labeled as being from 8 km on the ESA site
http://sci.esa.int/science-e/www/object/index.cfm?fobjectid=36381
is actually made up of images from between 2.1 and 0.5 km

Posted by: alan Jan 21 2005, 04:45 AM

About the movie, the images are much better than the butchered ones they are calling "raw"

Posted by: BruceMoomaw Jan 21 2005, 05:15 AM

Turns out that I was wrong in saying that that movie includes all the down-looking HRI images, and that therefore it proves that the last HRI images was taken at either 700 or 500 meters. The ESA's caption explicitly says (although I idiotically overlooked it) that those 108 descent images are taken from either the HRI OR the MRI, which looks down at an angle. Together those two cameras should have returned about 200 images on Channel B, which means there's still a chance that the HRI did get some of its still closer single frames planned between 500 and 200 meters. I sincerely hope we'll know more about this -- and a lot of other subjects -- after tonight's ESA press conference (2 AM Pacific time), which NASA TV is covering, and which I'll record.

In any case, there are dark channels a few dozen meters across clearly visible in images taken as low as 1 km -- one of them looks like an oxbow bend, while another branches. Some kind of fluid has been flowing all over Titan's surface, at least occasionally -- although it's still unclear whether it's liquid or viscous.

Posted by: BruceMoomaw Jan 21 2005, 05:42 AM

I just did a (long overdue) tally -- and, assuming that Channel B by itself did indeed return half the pictures, there should be 82 recovered frames taken below 20 km altitude by the MRI and HRI (the ESA movie shows 60), 46 returned from below 10 km (the movie shows 36), and 22 returned from below 5 km (the movie shows 18). So the question of whether it does include the lowest-altitude photos that were returned still remains.

Posted by: alan Jan 21 2005, 06:21 AM

I looked at the last 6 HRI images taken before landing again. There is a subtle difference between 710 and 713. The others, 716,718,719,720 appear to be the same as 713. They appear to be taken after the light was turned on. Hopefully they will be able to process them to eliminate the brightness difference caused by the variable distance from the light while leaving the details visible on the ground.
I noticed that the HRI from triplets 668,674,689,and 695 seem to cover one area and 650,656,662,671and 683 cover another. I have not seen any mosiacs from these yet. Perhaps in tomorrow's press conference.