It is a mystery about the early release of images at lpl.arizona.edu. I downloaded those images at work at about 3:15 PM CST and as a "CYA" copied them to floppy to take home. I have 11 images, and skipped some of the "duplicate" surface images.

Have the contacts at lpl.arizona been contacted?

My impression of the landing site is being very humid and "drizzly", much like the Pacific Northwest of America. I'm not sure of the hydrologic cycle of methane but I presume that it evaporates, condenses and precipitates like dihydrogen oxide.

--Bill

Concerning remarks "not much to see" or even "blank" for a number of bottom pictures of the triplets - some quick contrast processing shows that there is some information content in it. Lets see what the "masters of the DISR" will do with them...

I have yet to see any atmosphere data?

I'm curious as to what Huygens detected element wise.

This is an enhanced version of triplet 700, it does seem to show some linear surface features in an area that, at least from the RAW image, look featureless..

We also have to remember that in addition to being transmitted in a lossy way, the "raw" images have also been jpeged, so perhaps there is more low-contrast detail in the originals the DISR team is working with.

never mind - link was already posted

my opinion about the PR stuff (i wasn't online when all the fun started )
ESA should have done better in that respect, but as long as the science is good, you don't hear me complaining much.

I could be wrong, but I thing Europeans aren't nearly as web-based as the americans. I don't think a lot of europeans were watching the webcast. What impressions do you people get about this?

Anyway, I hope ESA will learn from all of this (incl. MEX) and will improve PR. Because in the end, it's the taxpayers who are paying.

What was the stage of the tide at the time of the landing? Was this at low tide or high tide? I'm not sure where the peri-whatever of Titan's orbit is.

--Bill

Hi Bruce -

they had an open directory that I was able to surf - there were never more than 16 links on the front page though, you are right.

I didn't get them all from the open directory (it was closed before I finished downloading- I was pacing myself!), but through another board and slashdot I was able to recreate the whole list - I haven't tweaked them at all. If this were an antiquities investigation, I could not vouch for the entire lists pedigree, that is I cannot trace each file to an orgin at ESA, but it appears to be complete and untarnished to my unprofessional eye, including the numbering.

Basically I put them up to save the bandwidth bills of some other fine folks who are running mirror as well. There are several places and blogs where you can find the same files now...

My personal speculation is that the DISR team wanted to share, but were told not to without ESA approval. They may have "inadvertantly" left a hole open on the site for a savvy seeker, and the rest, as they say, is history.

If any MIB from the ESA show up, I will deny it all. oops - probably shouldn't have typed all this then.

EDIT: doh - note to self - always read the NEXT POST DOWN before replying - thanks Pando for filling in the details....

Hmmm. Just how much is my continued silence about your ruthless criminal activities worth to you, Lyford?

More seriously: I went over that compendium of 367 triplets again last night, and -- while it's impossible to be absolutely certain, given the number of blank-looking ones -- there seems to be a minimum of 170 triplets actually taken during the descent on it. Since the original plan was to send back about 200 triplets (plus 2-4 single frames during the last few hundred meters), and since that return was halved by the Channel A failure, there MUST be some duplicates in there. (I still haven't heard back again from Bashar Rizk.)

I see a lot of duplicates - perhaps their automated processing was expecting triplets like...

a.b.c.d.e.f.g.h.i.j.k.l.m

but because some were on channel a - it automatically filled in the expected images with ones it had - so we get

a.a.c.d.e.e.g.h.i.j.j.j.m

Perhaps?

Doug

Check this out:
http://www.futura-sciences.com/communiquer.../sort/1/cat/525

Speaking of the channel A loss, any word of what can be recovered from ground based measurements. Or to be more clear, just how much doppler data will we be able to recover?

Ted

Unfortunately that location cannot be correct--the wider context does not match.

A large mosaic of the Huygens landing are shows a very distinctive fish-hook shaped feature just 'offshore', slightly to the left of center of the 'shoreline', while on this mosaic, covering a larger area, we see the same 'fish-hook' at the bottom right of the mosaic. After allowing for the different orientations of the two mosaics, it is clear that the 'ocean' has land, with drainage channels, on BOTH sides. The Huygens landing site therefore could not be where it is placed in that montage.

I think it would be nice to re-introduce the cartographical convention of the compass rose -- simply stick a tiny medallion or arrow in the corner of these close-up mosaics, so we know which way north (south, east or west) is.

"Titan probe's message not what was expected":
http://www.dailystar.com/dailystar/dailystar/57153.php

I quote:

The probe also tipped, losing its sensory lock on the sun - which will make analyzing the components of Titan's mysterious atmosphere a slower process that was originally planned. At first, he said he and his sleep-deprived colleagues in Germany didn't think they'd be able to salvage that data at all.

Why is that? Was the spectrometer supposed to look directly at the sun or something? I don't understand what he means.

I am not sure we know which way is which with any great precision at this point.

Makes sense to me. It would explain why the three views in most of the triplets don't match.

I would be interested to know just how the camera frames nest together, if they do at all. That way the surface triplets could be combined into a photomosaic, although the bottom camera images don't appear good for too much after landing, for understandable reasons. Also, how high was DISR off the ground while on the surface. This would depend on how much Huygens dug into the ground, and how it was tilted.

Ted

(1) The DISR team has put the raw images, back onto their site, claiming that they took them down while "analyzing the data": http://www.lpl.arizona.edu/%7Ekholso/data.htm . It's possible that they may have cranked up the contrast from the originals; I haven't done a detailed comparison yet to the originals on "Lyford's" site. (Also, I still don't see the 2 to 4 isolated HRI frames that they were supposed to get between 500 and 200 meters altitude; I suppose they might have lost those on Channel A. I'm awfully hard to satisfy.)

(2) The DISR camera head was supposed to be 45 cm (18 in.) off the ground after landing, assuming that the probe landed upright and didn't sink in. Since it MAY have sunken in a little, the images may be even closer to the ground.

(3) It was stated at the last press conference that the excellent Huygens tracking from those 18 ground radio telescopes (and they showed two graphs to show just how clear the Doppler and VLBI data was) should be able to recover the data lost from Cassini's own Doppler wind measurements "in full", although it may take a while to complete the analysis.

(4) Even if Guillaume did miscalculate Huygens' exact landing spot, his work seems to me absolutely superb, and indispensable right now for anyone interested in Titan.

I would agree concerning William's (to anglicize his name )work, despite the fact he is from that country And before anyone accuses me of being racist, I have travelled to France twice and am actually quite fond of the place...I am just poking fun at current jingo attitudes.
I am more than pleased to hear that we recovered the doppler data on the ground. That I think would have been a greater loss than a random half of the images. Also, does anyone know how the tilt of the lander effected the DISR. I have read that it was tilted a few degrees, but how it was tilted with respect to DISR's location would also effect its altitude. I hadn't realized that it was so low. That certainly, a la pathfinder before IMP was deployed, explains why it seemed to be in a field of giant boulders (although in the case of Pathfinder a few of the rocks proved to actually be quite large).

I agree - Bruce - I think they are higher contrast "raw" images - unless the first batch weren't ready yet - check out


TRIPLET.0.JPG

against my copy:


hmmm - need to download them AGAIN!

The best technical description of the DISR anywhere -- including the data on the angular overlap of its three cameras' viewfields -- is at http://www.rssd.esa.int/SB/HUYGENS/docs/SP1177/tomask_1.pdf . There, we learn that there were actually two sun sensors -- one for directional data both to tell which direction its cameras were looking, and crucial for interpreting the atmospheric composition data from its upward-looking spectrometers. (Huygens, however, had backup azimuth information from its roll gyro, which continued to operate throughout the descent.) The other was a solar aureole sensor to allow data to be obtained on the particle size of haze and cloud particles. It's hard to tell which of these the Arizona Daily Star is referring to.

I can't find a reference either in this article or anywhere else to the item I thought I'd read that the DISR would be 45 cm off the ground if Huygens landed on a flat surface without being sinking in -- it's possible I had it mixed up with the very definitive description of the spatial dimensions and angles of those post-landing images which can be found at http://www.planetary.org/news/2005/huygens_images_0115.html , and which says flatly that the DISR was about 40 cm above the surface when those photos were taken. (The accompanying size-calibrated photo is direct from the final Hugyens press conference.)

Continuing my monomania about the altitude at which the final returned images were sent: Tomasko's description says that, during the drop from 500 to 200 meters, single HRI images would be taken at intervals of about 8 seconds, with each one sent back immediately. Since Huygens actually hit the surface at about 4.5 meters/sec, it seems certain that it actually had time to take 7 or 8 HRI images during this period -- and once again I find it had to believe that all of them were returned via Channel A. Given the number of duplicated "triplets" on the DISR raw image site, it's possible that some of those last-second HRI images are sitting there falsely mixed in with unmatching "triplets" and unrecognized by us.

Either that or they haven't been released.

Man - been scrolling through the new ones at the DISR archive...

is it just me or are there compression artifacts galore, especially on the descent images?
Is this compression in the raw data you think, or just the web versions? Maybe introduced when they upped the contrast? Maybe that is the compromise that allows the PI's to get first dibs on the good stuff?

Compare triplet 226-



and

Tomasko's description of the DISR reveals that JPEG compression was actually used in the DISR before it sent its images to the transmitter -- in fact, a modified version of JPEG which is mildly lossier was used, to save weight in the system. So, when you JPEG a JPEG, it's not exactly surprising that the quality is somewhat low...

Ah, found it, thanks - on page 22:

Well, I would venture to say that those pics quality for low contrast status! - Now to plow through the rest of this document!
Perhaps they can reconstruct some of the missing pixels from other images...

I believe that last sentence contains a typo by Tomasko; he must have meant to say "...the SIGNAL is increased above shot noise..."

Whats that honeycomb pattern on the bottom image of triplet 0?

Possibly some sort of refraction based thing due to a totally out of focus image sent down an optic fibre bundle?

Doug

Can someone please clarify:

Are the images at http://www.lpl.arizona.edu/~kholso/triplets1.htm *exactly* the JPEG images from the spacecraft or have they been JPEG ( i.e. Lossy ) compressed again on earth, meaning that there exist better images, somewhere in ESOC or Arizona ?

well - they are jpg's - so they will have lost some quality from whatever they actually originate by virtue of the JPG process.

Bottom line - if you want the ACTUAL image data - wait 6-12 months and it should be on the PDS

doug

My concern is that a lot of the artifact features are also showing up in public release material, so clearly a good deal of it is really part of the nature of the images.

Yes - but given the time and effort that the scientists need to give this stuff (yet no one seems willing to let them have ) - such things can be reverse engineered out to a certain degree - along with any artifacts of the optical system etc.

Doug

djellison: Please read my question again. We know the images are JPEG compressed once, before transmission from the spacecraft and we will never get back what that lost. My question is, are the images lossy JPEG compressed a second time here on earth, and are there images without this second compression ?

As to giving the engineers time: the internet public has shown it can work faster and produce better images, and if the powers that be give us all the *raw* data, then we can work in parallel with them.
Hopefully this work will capture the world's attention and make them feel their money was well spent. I do not think ESOC have, to date, done enough to make them feel that way, and this should concern everyone interested enough to post here:

Am I just worrying about not making enough eye candy for Joe Public? Yes.
Will how Joe feels about the quality of the eye candy have an impact on future mission budgets ? Yes.

I understood it to mean the noise introduced by the compression, but I am not an imaging specialist, so I can defer to anyone else's interpretation.

I understand the tradeoff as far as the camera is concerned: Titan presents unique challenge for images. High contrast ground pattterns, but low contrast fog and clouds washes everything out in the atmosphere. What's a CCD to do?

ESA now has the raw images posted, the same overstretched ones you see at DISR
http://esamultimedia.esa.int/docs/titanraw/index.htm

Joe Public has seen the picture from the surface, seen the one with the very river-delta looking thing - gone "oo - titan - thats interesting - oo look, Kate Winslet's been nominated twice in the Golden Globes' The general publics interest in this sort of thing if fleeting, and momentary. and gone before they finish reading the 500 words on page 8 of The Times. Everyone I've shown the colour surface image has gone "wow - cool" - and then we're started talking about Kate Winslett again. The public does not and will not care. No ammount of released 500 tiny JPGs is going to change that. Ever.

A routine is in place for all space missions - the data is with the scientists who made it for 6 - 12 months, then it is released to the public at large. Cassini and MER have recently broken that mould with essentially useless JPG's - but every other mission, previous oo present - has done no more than ESOC did for the Huygens descent - Three 'headline' pictures and no more, and thats more than enough for the mainstream media - enough to show joe public - not enough to steal the scientists ( who lest we forget have toiled for two decades to get this data ) thunder on doing science with them.

And the proper raw calibrated data takes time to produce using techniques, technology and information that only the people who built the camera can do. No one else can do that. So, for goodness sake, let them get on with it!!

That we got what appears to be much of the data set in jpg format within 48 hrs is just as much as JPL do with Cassini and MER - if it IS the exact data as transmitted from Huygens - then hell - we're 6 months ahead of ourselves already.

We dont know how the images have been treated ( in the same way we dont know how the MER and Cassini images are treated ) - an 'auto levels' seems to be the most obvious way to get the most out of a murkey image of a murkey place in murkey conditions - result being it looks 'over' stretched. The Cassini auto-processing did it for 2 months - making each and every image of a saturnian moon into a white disk on a black background with no detail inbetween. A few weeks, and a few thousand images later - thats been fixed.

People have put 20 years of their LIVES into making these images - let THEM enjoy them - the proper data will be yours to play with soon enough.

Doug

Well, yes, but I think of the Voyager Neptune flyby. They showed the images as they came down to the ground. And lots of images, which kept the public interested. And come on, pictures simply at a quality that looks good on a television screen are not good enough to steal the science, so to speak. Same with the JPEG releases JPL does. Yes, scientifically, they are useless, but it allows the planetary society and other groups to generate decent looking images to keep enthusiastes interested. It seems like a good way of going about it. I think it is a fair compromise. I am certainly willing to leave measures in place to ensure those on the mission teams get first crack at scientific analysis. But good grief, I'm not a scientist, I am not going to supplant them. And for all their work, without taxpayers such as myself and most of us, whether we be Americans or from one of the ESA countries, they still wouldn't have had a mission, so I think we do have the right to see the results. I think the MER/Cassini approach has proven an excellent way to go, as was the Voyager approach for the pre-internet era. I would actually grant more flexibility to the DISR and Galileo teams...in both cases, one by design and one by the HGA problem, you had teams that had so few images that releasing them at high quality right away (although the DISR team seems to have done so anyway), even as JPEGS, would have left them to be scooped every time they released an image. But we are becoming so awash in images from MER and Cassini that this isn't as much of an issue. The stretching thing helps too, as, once fine tuned, it allows one to get a good look but prevents scientific analysis.

I think part of the reason the ESA held onto the raw images is the result of a bad experience with Giotto the probe that flew by Comet Halley. The first image released was done in false color to emphasize brightness variations which the general public was not able to interpret. Margaret Thatcher called the mission a waste of billions of dollars. The news media just shows the first images released and quickly forgets about it goung back to the latest celebrity trial. Not wanting the public to remember only some bland and grainy images they released only the best they had and held back the ones people would be disappointed by until the media has moved on. About the policy of holding data for six months to let the scientist on the project to study it first I think most of the science will come from the other instruments such as the spectrometers and chromotograph thus releasing the images shouldn't be a problem for them.

Imaging does result in a lot of science. As for basic geomorphology, the "raws" they release are somewhat useful. But as for multispectral analysis, they aren't good for much...for example, beyond being jpegs, you don't know if a patch that comes as red is really blue and is simply less blue than surrounding areas, or is really red, thanks to the stretching. And I think multispectral analysis may be where the greatest discoveries are made.

Yes -- splendid. I've gotten to page 16. The surface features are becoming more distinct, sharper.

Am grateful for the 350 images secured; a pity about the loss of the other 350.

All these years, wondering what's beneath the haze...am really enjoying this historic "piercing of the haze."

I'm not too disturbed by the loss of half the images since they were probably redundant of the ones already taken. We did get images from varying altitudes and most importantly from the surface.

And remember that many of the 350 lost images would have been from high up where visibility is almost zero and from the surface where practically nothing changes. So the number of lost 'useful' pictures is less than 350.

Does anyone know how long Huygens operated? There are conflicting reports:

- The surface science experiment worked for 3h 37min, including 1h 10 min on the surface.
- Radio telescopes on Earth received a carrier signal even after Cassini turned away from Titan (more than 4h 30min after entry interface). Was Huygens still transmitting data to Cassini at this time? Or only a carrier signal?

Did we miss data because Cassini couldn't see Huygens any more? Or was Huygens already dead?

Analyst

It seems criticizing ESA is becoming a sport these days:

http://www.spacedaily.com/news/oped-05i.html

While I agree with this ( and J.Bell's ) article in that the press conferences were overly nationalistic and pompous ( poetry... ) I do get the impression that spacedaily just tries to flak ESA because it can.

I mean Bell started reasonable with the complains about the poor quality webcast and endless nauseating compliments to eachother. But then he takes off and calls Europe a backwards, feudal aristocracy and such. And now this article. Again some good remarks about the poetry in the press conference. But whining that the pwetty pictures didn't come first and were not pwetty enough in the end is so incredibly... childish. This author probably never heard of building up tension or holding on to the best things. Not to mention that DISR is only one of the many instruments onboard.

I noticed complains about the picture quality on other forums as well, but as these are the same places where people see dinosaur teeth in mars rocks I can see where those complains are coming from.

Actually, Simon Mansfield's argument was more that ESA built up excessively high expectations in advance for the quality of the DISR photos, and so their actual fuzzy appearance was invariably a severe letdown that is going to unnecessarily turn more of the general public off of space exploration -- presumably in the sme way that ESA's bungling of the live presentation of Giotto's photos of Halley infuriated Margaret Thatcher, with God knows what effect on Britain's later level of contributions to ESA.

But I'm not sure I agree with him -- after all, if ESA HAD made it clear in advance that the Huygens photos were inevitably going to be rather mediocre in visual resolution, that would have turned the public off just as effectively. And ESA handled this latest Huygens press conference far better than it handled the last one -- no bureaucrats stealing the limelight this time (except maybe for Lebreton, Southwood and Diaz taking up the first 20 minutes or so of the p.c., for which I think they can be forgiven. I was actually unexpectedly touched by Southwood suddenly bursting into apparently sincere tears during his statement.) My only real objections to this p.c. were:

(1) ESA still hasn't released, on the web, the various graphs that were shown as slides -- slides that, even at this state, contain some very interesting-looking information, but which were almost impossible to read properly during the Webcast. (More on this subject later, since I've just spent a couple of hours squinting at them on Spaceflight Now's recording of the p.c., and as I said I think there's some quite interesting stuff visually apparent on them that wasn't mentioned verbally by the scientists.)

(2) The really sloppy job the DISR team did on pasting together that panorama, which I myself found to be very interesting and rather dramatic-looking -- but which was so badly put together that the horizon lines in the various frames didn't even match up properly. Christian Waldvogel's version at http://www.futura-sciences.com/communiquer...g/cat/525/page/ is infinitely better. (Despite that, the ESA panorama DID get a round of applause from the reporters -- they weren't THAT disappointed with the photos.)

(3) The last straw, for me, wasn't ESA's fault at all -- it was NASA TV's fault, for cutting away from the p.c. right in the middle of Tomasko's reply to a rather important question to switch back to their endless round of rerun video clips (in this case, a stupefyingly dull clip of some piece of Shuttle equipment being installed, followed by the trillionth replay of the Deep Impact launch.) I came very close to throwing something at my computer screen at that moment.

So: ESA still very badly needs to clean up its act when it comes to its overall public presentations of space science data -- but it wasn't as bad, overall, as Simon and Jeff Bell have made out.

One has to consider ESA's performace w.r.t. the main stream media. The next day's papers, and that evenings news. For that - their performace and output was sufficient. A couple of pictures, a couple of sound bites - thats all that was required. Anything above and beyond that is a bonus for the TINY minority who have a greater than passing interest in it.

Doug

If these two ****** from spacedaily can build a better camera with the technology available 10/11 years ago, have it survive the launch, another 7 years of spaceflight, entry into the atmosphere into a totally alien environment, temperatures of -200 then I think they're in the wrong job.

Yes - sadly, there are some who think that because they can buy an 8 megapixel digital camera on the highstreet there's no reason why you cant put one on Titan.

Jim Bell's articles are best avoided. He's a troll that somehow - is given the title 'journalist'. In the forum of life - he should have been banned some time ago. He gives other, more decent writers ( JimO, Bruce ) a bad name.

Doug