Huygens!

[t00fri]

I suppose much of NASA's argumentation for the water-icy nature of the surface used support from Cassini's near-infrared sprectrometer data,

[Evil Dr Ganymede]

I do wish you'd put non-colorised images up so that we can see the original data... colour can be very misleading (it can give false impressions, especially when you make the dark stuff look blue to give the impression that they're oceans).

Plus, if they've been taken down from the LPL pages then I suspect that's because they were released prematurely and that person has not been authorised to release the images yet - which means you shouldn't be showing them here either. Speaking as someone who worked for a short time on an imaging team (Galileo) I suspect they'd be very pissed off to find that someone has grabbed an image that wasn't supposed to be online yet and posted it on a public forum, even if they did put credits up. Have you emailed them to ask if it's OK for you to post the images here? If not, I would strongly recommend that you do so.


That said, the image on the right does look rather reminiscent of river channels. But I still don't think that the low-res image I was looking at shows them.


EDIT: Thanks for changing the image. But do keep in mind that things are initially going to be a bit chaotic, and images may be pulled at any time for the next couple of days.

[t00fri]

The Titan images are for public viewing only and the UA, ESA, and NASA logos must remain visible for redistribution or downloading.

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

[fsgregs]

Guys, there is more to the debate than the surface. I clearly remember our discussions and the arguments on the forum that Titan was dark, very smoggy and like twilight, with neither Saturn nor the Sun visible from the surface. Yet, those claims seemed to go against what ESA and NASA were claiming at the time in all their artwork. Every image of what Titan looked like on the surface, done by their graphic artists, all showed a smoggy but well lit Titan with Saturn rising on the horizon. Now, it seems they were right.

If you also recall, we had some disagreement over the color of the atmosphere, particularly near the top. I was told by other forum members that the true color of the upper atmosphere was not blue but clearly a brown/beige. I had worked for hours to recolorize the atmosphere with a bluish upper tint to match ESA's artwork and photos but was politely told I had it wrong. Yet today, plastered all over the world news, are both photos and dozens of ESA released sketches/images showing Titan with a distinct blue upper atmosphere.

I really want to get this right in my educational activities. I HATE to tell someone something in a document that is simply not true. Either ESA is still intentionally fooling everyone, or the color of Titan's atmosphere is not correct in Celestia and should be changed.

HELP!!!

Frank

[Dollan]

Can't agree here fully, Doc... I think that they are very reminiscent of drainage channels; in fact, they really remind me of some aerial images of rain-wash gullies in my old stomping grounds in New Mexico -- not that I, for a minute, am advocating them as being such!

I think we'll have a better idea in the next few days.....

[Guest]

Hello Evil Dr Ganymede,

I hope I wasn't improper by posting links to them thar raw images (30 enthusiastic Celestia fans shouldn't make a web server fall over, should it?), but at least you'd have seen the original grayscale imagery before the images were removed.

Nice point about lobate edges to lava flows - I remember it on the SAR imagery discussions. I squinted at the first-released image again, and could almost see your preference for those dark meaders being shadows of lava flows, but since the shadows seem to occur in 3/4 of directions, and there are no bright sides (except one against the shadow where the 'channel' lead to a picture corner, implying the relief of a channel), I think we see an albedo feature.

The orange-colourised image t00fri posted above is the centre picture of triplet.541.jpg which does cover the area of the first-release picture - compare the lower half of it to the first-released image rotated 90?° clockwise. This lets us see that it does look more like a 'river' network.

The drainage channel was mentioned by an ESA scientist interviewed by the BBC as a first impression. He stressed that the channels would be due to seepage, not rainfall (it doesn't rain on Titan ).

The 'river valley' phrase is AFAIK my own 'invention' for explaining Titan features, no ESA/NASA person said it.

Actually, I disagree with the ESA interpretation that the drainage channels flow toward a 'shoreline'. First they flow away from that dark area, and second I too am not convinced the dark area is open liquid. The 'waves' claimed to be almost visible could be dunes.

By the way, if anyone else is interested, you can match up the 'droplets' from one triplet picture to another. I guess that might mean they really are droplets on a screen. Triplets appear to be ordered so the top one is looking to the horizon, the next at 45?° down to the ground and the lower one straight down. Put two triplets side by side, and you'll see what I mean.

Spiff.

[maxim]

Guys, you are posting faster than I can read!

I just dropped in to say how 'geil' I found that success to be.

maxim

[t00fri]

Guys, there is more to the debate than the surface. I clearly remember our discussions and the arguments on the forum that Titan was dark, very smoggy and like twilight, with neither Saturn nor the Sun visible from the surface. Yet, those claims seemed to go against what ESA and NASA were claiming at the time in all their artwork. Every image of what Titan looked like on the surface, done by their graphic artists, all showed a smoggy but well lit Titan with Saturn rising on the horizon. Now, it seems they were right.

If you also recall, we had some disagreement over the color of the atmosphere, particularly near the top. I was told by other forum members that the true color of the upper atmosphere was not blue but clearly a brown/beige. I had worked for hours to recolorize the atmosphere with a bluish upper tint to match ESA's artwork and photos but was politely told I had it wrong. Yet today, plastered all over the world news, are both photos and dozens of ESA released sketches/images showing Titan with a distinct blue upper atmosphere.

I really want to get this right in my educational activities. I HATE to tell someone something in a document that is simply not true. Either ESA is still intentionally fooling everyone, or the color of Titan's atmosphere is not correct in Celestia and should be changed.

HELP!!!

Frank

Frank,

it was Grant who argued that the sun could not be discerned from Titan's surface while others (including myself and also Spiff ) argued rather that some (vague) location of the sun should be possible. The case is still open and remains interesting.

As to the upper atmosphere color, there seems little doubt that the blue/purple is strongly exaggerated and could never be made out /visually/. This is also clearly stated in the official image captions, if I correctly remember.

Bye Fridger

[Dollan]

As a clarification, the image I posted came from spaceref.com, and was an official press release.

...John...

Actually, that picture Dollan posted above is stated by ESA to be "This is one of the first raw images returned by the ESA Huygens probe during its successful descent. It was taken at an altitude of 8 kilometres with a resolution of 20 metres per pixel. It shows what could be the landing site, with shorelines and boundaries between raised ground and flooded plains."

I can't make it out as that, instead maybe as a series of mountain ranges, but then the shadows are all wrong - or are they lakes, and I'm wrong!? .

Yes, I just found out the http://www.lpl.arizona.edu raw data pics got pulled...

Spiff.

[Evil Dr Ganymede]

The Titan images are for public viewing only and the UA, ESA, and NASA logos must remain visible for redistribution or downloading.

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

Yes, but the fact remains that they've pulled the images from that very website, which implies that they don't want the images to be publicly released yet. And if the source doesn't want them to be shown on their own public website, then that would indicate that nobody else should be putting up copies of the images on a public website like this either.

Still, email the guy and ask to make sure. If he says OK then you're fine, but if he says not OK to post the images then you'll know you have to abide by it.

[Evil Dr Ganymede]

Well, I think my interpretation based on that one image I linked to does still stand to an extent. However, I've only had a brief glimpse at the other images (namely, that one picture that fridger posted - I didn't see the rest before they were pulled). Especially at this early stage, there are going to be a lot of ideas thrown around that would only get whittled down by looking at more data.

Either way though I do think it is VERY premature to start talking about river channels and shorelines. I'll be more convinced either way when more data is processed and released but right now I am still skeptical. I certainly don't think we're looking at a shoreline though, but I am now considerably more open-minded (based on that glimpse of the triplet image) that there might be some kind of drainage channels down there.

In other words, I reserve the right to change my interpretation as I see more data .

[chris]

To fuel further discussion, here are all of the raw 45 degree images pasted together horizontally:

http://www.electrasite.com/pano567-nodupes.jpg

--Chris

[Dollan]

Just a thought... what about some kind of ice field? Or even a former lake bed or some such analogue?

I know, I know, I'm throwing things out here a hundred miles an hour based on those triplet pictures, as well as the three main releases, without waiting for more info to be released... but I am so damned excited about this! This is the first time that I've been able to see, as it happens (okay, minus the time lag and preparation time) a new world unfold.....

...John...

[lostfisherman]

Peoples eyes will play tricks on them as they peer at those rather small raw pictures. It is rather fun though! Do those ice rocks (I would think that that's what they are) look to be half buried? Just a thought.

[rthorvald]

Do those ice rocks (I would think that that's what they are) look to be half buried?

Some of them do.

I played a bit with the pics in Photoshop to see if i could bring out some detail, sharpen contours etc... All i got was blacker and whiter pixels...
To me it all looks like a plain, low hills in the distance. The bright patterns just looks like snow or something to me...

-rthorvald

[maxim]

To fuel further discussion, here are all of the raw 45 degree images pasted together horizontally:

http://www.electrasite.com/pano567-nodupes.jpg

--Chris

There was a worldwide common agreement here at Z-Bau, N??rnberg, that the landing area will be definitely called 'Fr?¤nkische Schweiz', because the landscape on these pics looks just like the same-named landscape just some dozen kilometers outside N??rnberg.

maxim

[Brian Short]

I was thinking that it would be nice when we get more images from the surface, so we can have a nice panorama, but then I remembered that the camera only rotates with the probe, so the shot we have from the surface is the only one we'll get Still, I'm looking forward to some more images from the descent. I hope that the results from this mission will prompt NASA or ESA to build a dedicated Titan orbiter/lander combo. How often do launch opportunities come along for Saturn missions?

My impression of the official photos released so far is that the patterns definitely look like drainage patterns flowing into an area of liquid. Hopefully we'll learn soon what the truth is.

Brian

[Dollan]

With the work going on with Prometheus-style probes... we'll be back. I don't know whehn, but we will....

...John...

[t00fri]

Quite spectacularly, on the ESA site

http://www.esa.int/SPECIALS/Cassini-Huygens/SEMC8Q71Y3E_0.html

we now got the first color image of Titan's surface!



Also the sizes of the "foreground rocks" and characteristic distance scales were given. In the Darmstadt WEB-log it was stated today that the foreground objects on the photo are big rounded pebble-stones rather than ice blocks! The darkish terrain on which Huygens landed is stated to consist of a mixture of water-and hydro-carbon ice. In 18-20 Km altitude there is a dense band of methane (CH_4) clouds. They speculate that there must be an extensive methane reservoir on the surface, with the methane being liquid at the surface temperature of -180 degrees Celsius, but constantly evaporating into the atmosphere.


Together with another beautiful 'landcape'-composite I could soon start revising my Titan surface texture for Celestia. But I'll wait a bit since more color images are surely going to come. Well you may find my first attempt in 'users'->t00fri's Titan...

Bye Fridger

[t00fri]

Since today it's weekend, I could not resist playing a bit with the latest composite image on the ESA site. The original looks like this



For completeness, here is the caption

This composite was produced from images returned yesterday, 14 January 2005, by ESA's Huygens probe during its successful descent to land on Titan. It shows the boundary between the lighter-coloured uplifted terrain, marked with what appear to be drainage channels, and darker lower areas. These images were taken from an altitude of about 8 kilometres with a resolution of about 20 metres per pixel.

I applied the following manipulations to the original, in order to improve the visual impression of the striking landscape:

1) With Photoshop, I fitted the brightless levels of the individual images in the composite and with the patch tool I eliminated the visual borders....

2) I then mapped the precise color spectrum from the first color image of titan's surface above to the grayscale composite, using GIMP2. The result looks like this:



I think this gives quite a 'lively' 3D impression of the rich 'landscape' as seen by Huygens during its landing approach.

Today, in the German TV, ESA scientists commented this image by stating that there is now substantial evidence accumulating for a 'liquid' landscape, with rivers of methane (CH_4).

Enjoy,

Bye Fridger