Printable Version of Topic

Posted by: Decepticon Nov 25 2005, 01:37 PM

Getting the Holiday Spirit going.

This is a Distant Flyby @ 10,409KM CA
Hope we will see a NEW Titan map Soon!?
If anyone has a animation of the flyby Please Post It!

Posted by: Decepticon Nov 25 2005, 01:40 PM

One things for sure, this flyby should provide a better look at areas in between all previous flybys.

Posted by: AlexBlackwell Nov 25 2005, 05:35 PM

I'll defer to Jason (volcanopele) on this one. That said...

The last listing (August 12, 2005) of T9 science objectives I've seen listed ISS's primary goals during this flyby as "Low-phase global map, and an examination of wind/cloud motions," though I wouldn't be surprised if ISS NAC filled in some gaps as a ride along. In fact, I've seen "ISS High Res NAC" slotted for 6-4 hrs. before T9 C/A; however, this might refer to the cloud observations.

On the other hand, I believe that while UVIS has control of pointing during the 6-hour window surrounding T9 C/A (4 hours before and 2 hours after), both UVIS and ISS NAC are listed as pointing towards Titan's specular point during this time frame, so gap-filling high resolution imagery could be acquired.

CIRS ("trace constituents in Titan's stratosphere.") and VIMS ("medium resolution regional map") acquire data further out while inbound to T9 C/A.

Posted by: Decepticon Dec 3 2005, 09:27 PM

Does anyone have a animation of the approach?

Posted by: volcanopele Dec 5 2005, 06:44 PM

here is a view of Titan taken during the middle of the GLBMAPNLP001 observation that Alex mentioned:

http://pirlwww.lpl.arizona.edu/~perry/T9.jpg

Posted by: jmknapp Dec 8 2005, 01:05 PM

Here's an animation:

http://cboh-t.cboh.org/~jmk/titan26dec.avi

Posted by: Toma B Dec 13 2005, 06:01 AM

I know this does not have anything to do with Dec 26th flyby but...look at this image from "Where is Cassini now"....

I wonder if they will take pictures of that...

Posted by: ugordan Dec 13 2005, 09:12 AM

Looks like another one of those KODAKMMT photo-ops
I'll be VERY disappointed if they don't snap at least one frame at this scene. You know, for optical navigation purposes and stuff

Posted by: Decepticon Dec 13 2005, 01:17 PM

I'm pretty sure I've seen similar images already.


I hope we get a NEW Titan map soon, I was hoping after this flyby.

I even tried myself to make a new map. Purely a laugh in my opinion.

Posted by: Decepticon Dec 17 2005, 06:05 PM

http://cassinicam.com/

Neat page, updates every 5 mins.

Posted by: ugordan Dec 17 2005, 06:29 PM

Maintained by none other than our Joe Knapp a.k.a. jmknapp

Posted by: AlexBlackwell Dec 19 2005, 04:11 PM

The T9 Mission Decscription Document (http://saturn.jpl.nasa.gov/multimedia/products/pdfs/20051226titan_mission_description.pdf) is now available on the public Cassini website.

Posted by: Matt Dec 22 2005, 01:17 PM

I like the Cassinicam!

Posted by: ustrax Dec 22 2005, 07:26 PM

Me TOO!...

Posted by: jmknapp Dec 22 2005, 07:44 PM

Good to know it's appreciated--wasn't getting many hits until recently.

Posted by: AlexBlackwell Dec 22 2005, 07:55 PM

Thanks for the work, Jim. Incidentally, I believe at one time JPL's David Seal had a "Real-Time" simulation display on the internal Cassini website, which showed the FOVs for ORS pallet instruments and RADAR.

Posted by: elakdawalla Dec 22 2005, 08:43 PM

The whole cassinicam site is very very much appreciated. So much so that I have been checking every day to see when the S17 page for ISS is going to show up here: http://www.cassinicam.com/sp/iss.html
Is such a page in the works, please please please? They are SO helpful in making sense of what all the raw images were captured for...

--Emily

Posted by: ustrax Dec 22 2005, 09:01 PM

You should do some advertising...
Talk with me...I so very nice prices!

Posted by: ustrax Dec 22 2005, 09:04 PM

DO very nice prices...

Posted by: Tman Dec 22 2005, 09:15 PM

http://www.cassinicam.com/sp/S16/req/ISS_018EP_MUTUALEVE012_PRIME.html

That's exactly the information I http://www.unmannedspaceflight.com/index.php?showtopic=1842&view=findpost&p=32658 was searching for... That's great Joe! Thank you for putting these informations to the web!

Posted by: jmknapp Dec 22 2005, 10:08 PM

It's great that they post the so-called "event kernels" to the NAIF website, but there's always about a 12-day gap between the end of one science plan and when the event kernels for the next one are released. For example, the S16 kernels came out on Nov. 22, and covered Nov. 10-Dec. 15.

Now we're a week into S17, but the event kernels probably won't be released until about Dec. 27th. Which kills me too--for example the Dec. 26th Titan flyby and any Enceladus observations on the 24th-25th are under the radar--no pun intended!

When they come out I'll run the program to crunch them into html & post it to the web site.

Posted by: Roby72 Dec 27 2005, 10:16 PM

Nice images vulcanopele !

I suspect some fog over the "H"/Fensal-Aztlan regiion especially over the middle of the H. Its a little brighter than the dark regions.

Robert

Posted by: alan Dec 27 2005, 10:16 PM

Hey volcanopele, you moved again. NASA should dump the shuttle and get in touch with your moving company.

Posted by: djellison Dec 27 2005, 10:30 PM

Have you seen the R,B,G sequence...

It flicks filter to filter, but you get the idea...I'll TRY to do the colour version, but it all moves so quickly it'll be a mess.

Doug

Posted by: djellison Dec 27 2005, 10:47 PM

The colour one, as I thought, terrible

It's something to fudge the between-filter-motion of a martian sunset movie at 20s intervals, but if you see a proper movie of this looking nice, then Jason's spent a thousand hours in Photoshop

Doug

Posted by: djellison Dec 27 2005, 11:07 PM

And a random filter merge of some WA's in the VIMS style

Doug

Posted by: ugordan Dec 27 2005, 11:16 PM

LOL, that would look nice along these two:

Looks like green is in this year

Posted by: djellison Dec 27 2005, 11:27 PM

Some nice sequences of WA imagery that give a good sense of being somewhere real.

You need the latest Quicktime to view these, they come out MUCH smaller than any Anim Gif I've found.

Doug

Posted by: volcanopele Dec 27 2005, 11:33 PM

Yes, but the colors mean different things.

Nice work, Doug, though there is no Quicktime on my Sun machine (I have to actually get up out of my workstation, go ALL the way to the other side of the room to view it on the MAC

Posted by: ugordan Dec 27 2005, 11:34 PM

Hm. And I was wondering why Media Player Classic wouldn't play the clips...
Any chance you could do an avi version? QT update is a no-go over dialup

Posted by: David Dec 28 2005, 12:05 AM

In this one:
http://saturn.jpl.nasa.gov/multimedia/images/raw/raw-images-details.cfm?feiImageID=59293

There's a noticeably smooth curve on the lower-left hand side of the "channel" joining the two sides of the H. Could this be -- or have been, which I guess in this case is a different thing -- the result of fluid action?

I still cannot help feeling that Titan looks like a beach at low tide; and I keep wondering when the ocean is going to come back.

Posted by: nprev Dec 28 2005, 01:00 AM

I don't know if the word "enigmatic" could ever be over-used for this place; every time I see a new pic, my mind goes crazy trying to figure it out...

I think one huge problem that we're all having is trying to relate the truly strange to the familiar; heck, even the Huygens surface pics look so much like Venus or in some respects Mars that I have to constantly remind myself that I'm looking at ice pebbles and complex hydrocarbons instead of silicate rocks and soils!!!

My point here is that the materials of Titan's surface--and probably also the processes that shape them--are so far out of our legacy experience that their behavior may not fit our intuitive expectations, despite the observed prima facie similarity of many features to those on the terrestrial planets. Huygens could only tell us a very little bit about the composition and mechanical properties of its landing site, and of course that's not meant as criticism; what a brilliant success in the face of so many unknowns!!!! However, I'm absolutely certain now that we need some serious, in-depth dedicated follow-on missions before we'll even begin to understand Titan; we're really at the "Mariner 4" stage right now in many ways.

Posted by: jmknapp Dec 28 2005, 03:04 AM

S17 now up, covering through Jan. 27, 2006:

http://cassinicam.com/sp/issS17.html

Posted by: tedstryk Dec 28 2005, 03:06 AM

Am I imaging it, or does the atmosphere seem a bit less hazy in some of the images this time?

Posted by: elakdawalla Dec 28 2005, 03:31 AM

Yay! Thank you! Now I have no excuse not to work on the rev 19 page...can't wait to delve in to all of those delicious icy satellite images that have been coming up recently.

Cool pics coming in from T9!

--Emily

Posted by: ermar Dec 28 2005, 04:57 AM

Nice picture, Emily! I notice that there are a series of raw images in that sequence showing Saturn disappearing behind Titan's limb; could someone with more skills than me make an animation of that? Also, there seems to be a double layer in the atmosphere in the raw images I see of the Titan limb, with two layers separated by a darker band. Is that an actual feature or an imaging artifact of some sort?

Posted by: tallbear Dec 28 2005, 08:57 AM

you must be grabbing the reconstructed C-kernels ( ?? )
( with letters ra and file extension bc )
not sure if the predict C-kernels go out to any public URLs
.... curious as to what kernels you are using ....

Posted by: tallbear Dec 28 2005, 09:06 AM

is it the S17 E_kernel ???

S17_CIMSSSUPa.bep

Posted by: djellison Dec 28 2005, 11:07 AM

cough ahem

http://www.unmannedspaceflight.com/index.php?showtopic=1730&st=15#

See .mov attachments ( x3 )

And nope, sorry, I'm not making .avi's of them, I'm sticking to QT from now on, it works beautifully There's bound to be a copy of QT on the cover of a PC mag etc. It's worth it, H264 ( or whatever it's called ) it's astonishingly good.

Jason - you've got it easy, I had to walk all the way upstairs to use Quicktime Pro, as I made the imagery down here ( points at living room sofa ) and the movie up there (points ALL the way up the stairs to the office )

On reflection, mind you, I think I'd rather have your seat

For those that dont want quicktime, have a look for Quicktime Alternative ( and real alternative ) both freeware options instead of QT or Realplayer. Not sure if they have the H264 codec in there, but there must be another option somewhere.

Doug

Posted by: jmknapp Dec 28 2005, 11:28 AM

The S17 page uses the following:

S17_cmd_pj.bes
S17_status_pj.bes
S17_CIMSSSUPa.bep'

I take it that the 'p' designation means predicted and 'j' is the version code.

The as-flown ('f') versions seem to come out about 3 weeks after the end of each science plan, as in:

S15_cmd_frevA.bes
S15_status_frevA.bes
S15_36noise_a.bes

S15 ended Nov. 10 and the above kernels came out on Dec. 1.

As for C-kernels ("camera" pointing info) the predicted versions do go out to the public NAIF website. There are predictions covering the entire primary mission supplemented by "as flown" versions covering like 5-day periods that come out piecemeal. For example the latest CK is 05347_05352ra.bc covering Dec. 13-17.

Posted by: Sunspot Dec 28 2005, 11:50 AM

Do I need to have Quicktime 7 to view those files? You can download it here:

http://www.apple.com/quicktime/download/win.html

My computers too old to use QT 7 - I still have Win ME - hopefully will be getting a Mac next month though


Enjoy the exquisite High Definition (HD) footage of the NASA Space Shuttle in preparation for launch, launch and views of the earth from orbit.

http://www.apple.com/quicktime/guide/hd/nasaspaceshuttle.html

Posted by: djellison Dec 28 2005, 12:18 PM

http://www.codecguide.com/
Tip: QuickTime HD clips
Here is a tip for all those people that want to play QuickTime HD clips (the ones that use the new H.264 codec) without QuickTime (Alternative).
You can play them if you hae the K-Lite Codec Pack installed. Download a .mov file to your harddrive. Then simply rename the file from .mov to .hdmov.
The required components from the K-Lite Codec Pack are:
- ffdshow (for H.264 and AAC)
- MP4 splitter
Playback will be faster and better than with QuickTime itself! Note that this method only works for HD QuickTime clips, not for normal QuickTime clips.

http://www.videohelp.com/tools?tool=QuickTime_Alternative

There's options out there

Doug

Posted by: Matt Dec 28 2005, 06:28 PM

"still cannot help feeling that Titan looks like a beach at low tide; and I keep wondering when the ocean is going to come back"


If there was an ocean, wouldn't high/low tide always be in the same places on Titan?

Posted by: ugordan Dec 28 2005, 06:34 PM

Generally, yes, but Titan's orbit is slightly eccentric meaning that its sub-Saturnian point wobbles slightly on a 16 day period. Any surface liquid tides would probably follow the wobbling, lagging somewhat behind the rigid, icy crust.

Posted by: JRehling Dec 28 2005, 06:50 PM

It would be possible for tides to move laterally even if Titan had the same subsaturn point always. Consider that there is a solid geoid to Titan (which would alter in shape only slightly between apoapsis and periapsis) and a liquoid (??) that would alter in shape to a larger degree. At periapsis, the liquoid would be deeper at the subsaturn and antisaturn points. As Titan moved towards apoapsis, the liquid would flow outward, radially (as local topography allowed) towards the ring that ran over both poles along 90E and 90W. Then when it returned to periapsis, the liquid would flow back to the subsaturn and antisaturn points.

If that were happening, we would expect to see some signs of channels extending inward and outward in all directions radially distributed around the subsaturn and antisaturn points. I don't think any such thing has been seen in the north/south directions, so this tidal sloshing is probably not happening to any great degree.

Posted by: AlexBlackwell Dec 28 2005, 07:13 PM

Some pre-Cassini references:

The tide in the seas of Titan
Carl Sagan & Stanley F Dermott
Nature 300, 731−733 (1982)
http://www.nature.com/nature/journal/v300/n5894/abs/300731a0.html

Tidal Dissipation in Oceans on Titan
Icarus 113, 39-56 (1995)
William D. Sears
http://dx.doi.org/10.1006/icar.1995.1004

Tidal Dissipation on Titan
Icarus 115, 278-294 (1995)
Frank Sohl, William D. Sears and Ralph D. Lorenz
http://dx.doi.org/10.1006/icar.1995.1097

Tidal effects of disconnected hydrocarbon seas on Titan
Stanley F. Dermott and Carl Sagan
Nature 374, 238-240 (2002)
doi:10.1038/374238a0
http://www.nature.com/nature/journal/v374/n6519/abs/374238a0.html

The Seas of Titan
Ralph Lorenz
Eos, Trans. AGU 84, 125, 131-132 (2003)
http://www.lpl.arizona.edu/~rlorenz/seasoftitan.pdf

Posted by: jmknapp Dec 29 2005, 11:57 AM

I should note that the ISS/Science Plan page for http://cassinicam.com/sp/issS17.html includes only the items related to the ISS subsystem (more or less--any item which includes the terms ISS, WAC, NAC or KODAK). For a complete list of all events per the S17 event kernels, see:

http://cassinicam.com/sp/allspS17.html

That would include such non-ISS activities as this magnetometer item:

Posted by: BruceMoomaw Dec 29 2005, 04:53 PM

John Rehling's tidal-channel suggestion for Titan -- since what we're mainly talking about is migrating tides driven simply by the considerable libration that Titan undergoes in its mildly eccentric orbit -- may be better supported by the current evidence than he thinks. Surely, given that the tidal bulge of any liquids on Titan would slosh back and forth in an east-west direction, the channels gradually gouged by tides would be more pronounced in that direction than in a north-south one -- and indeed the dark channels we see on Titan DO tend toward east-west directions, although of course there may be meteorological reasons (or pure-chance reasons) for that. Some of these channels may be classic "tidal bores" like the Bay of Fundy, gradually carved during those periods when Titan's playas do have some liquid in them from its occasional methane cloudbursts.

Posted by: jmknapp Dec 29 2005, 07:49 PM

volcanopele:

The latest images from T9 include a lot of shots of Sotra Facula, your new "location." Anything new of particular interest re that island?

Posted by: belleraphon1 Dec 29 2005, 11:04 PM

Hello .....

new as a registered member, but I have been reading this blog ever since
volcanopele felt compelled to shut down TitanToday......

Does anyone know what a specular reflection would look like coming through all that Titan haze?

If you look at the raws from w00012654 through w00012628 you will see a bright spot in the center of each image. It seems to be there no matter what set of filters is used.

Interesting ... just another 'bright' feature on this hard to decipher world?
Or a specular reflection?

See http://saturn.jpl.nasa.gov/multimedia/images/raw/casJPGFullS17/W00012645.jpg
as an example



Craig

Posted by: jmknapp Dec 29 2005, 11:31 PM

Interesting... here's a set of them:



I suppose it would be neater to see it come off the dark area.

Posted by: belleraphon1 Dec 30 2005, 12:18 AM

Thanks......

Too bad......

but what would a bona fide specular reflection look like coming through the haze.

I would assume that has been modeled? Is there a pre-cassini (or post SOI) paper out there on this specifically?

Craig

Posted by: belleraphon1 Dec 30 2005, 01:27 AM

Ok.... I am answering my own question ......guess I am really fishing for a qualitative image in my mind's eye ... would a specular reflection look like a small bright glint or a larger bright blob?

Below are links to papers on this question from googling .....a West et al analysis pre-CASSINI, the Cambell et al radar paper from 2003, the West et al paper from 2005 and the Emiliy Lakdawalla article on West from the Planetary Society....

This paper was pre-CASSINI on expectations for specular reflection ..... they seem to feel that glints should be visible from adaptive optics on the ground
R. West, S. Salinas, M. Tsang
http://sci.esa.int/science-e/www/object/doc.cfm?fobjectid=35115

This is 2003 radar paper released by Campbell et al seeing glints in radar wavelengths that gave us all hope....
Campbell et al
http://www.astro.cornell.edu/~lcarter/papers/titan03.pdf

This is the West, et al paper from this year seeing no glints in infrared wavelengths
http://www.nature.com/nature/journal/v436/n7051/full/nature03824.html

This is Emily Lakdawalla's piece from The Planetary Society on the papers above
http://www.planetary.org/news/2005/0805_No_Oceans_on_Titan_for_the_Present.html

Interesting that looking at the figure in the 2005 West paper, the glints seen at radar wavelengths were NOT in the dark areas, but primarily in areas bordering the dark 'playas' or on the lighter expanses......

what a fascinating world this is.......

Craig

Posted by: BruceMoomaw Dec 30 2005, 02:51 AM

Yeah, at the COMPLEX meeting Elizabeth Turtle showed a map of the locations of the specular radar reflections seen thus far -- and they have absolutely no detectable correlation with the dark areas.

Posted by: Decepticon Dec 30 2005, 03:54 AM

Small scale lakes have not been ruled out. I'll hold on to the that for now.

We still don't know if some dramatically seasonal change might cause a shift in this possible dry season.

Posted by: belleraphon1 Dec 30 2005, 02:18 PM

This really belongs in the radar thread but ....

I like the model that posits a lot of methane 'snowed' out in the north waiting for a spring thaw......

The north polar regions have been in darkness now for at least 7 years. Interesting that the Ta radar swath found a lot of terrain identified as
homogenous unit (see the CHARM RADAR pdf by Lopes et al p20) ..... this was past the sunline ..... methane/ethane snow?

Yet the equatorial regions are not exactly bone 'dry'..... Huygens seems to have landed on 'wet beach sand' ....

All the more reason to keep CASSINI going for a long extended misson and watch for seasonal changes.

Will Titan start to sparkle with specular glints come northern spring?

Craig

Posted by: PhilCo126 Dec 31 2005, 12:28 PM

Joe, do You have an online JPL link for that 26 Dec Titan flyby ... movie doesn't play for me


Best NASA-JPL .gif image for me about Cassini-Huygens remains PIA06119.gif

Posted by: jmknapp Dec 31 2005, 01:58 PM

Wow, that's a good animation--shows exactly what they did on that flyby (Oct. 2004)! I'm not aware that they make one of those for every flyby.

Posted by: PhilCo126 Dec 31 2005, 02:14 PM

Which other PIA-numbers did You find ?
( Other then PIA06119 and PIA06147 )

Posted by: Decepticon Dec 31 2005, 04:52 PM

My attempt at merging earlier mapping with the most current Titan map.

Just trying to see what it would look like.

Posted by: JRehling Jan 1 2006, 06:33 AM

Nice work -- I appreciate it.

I remain ever-eager to see the final Cassini map of Titan, which is being unveiled slowly. This "dance of the seven veils" certainly does build anticipation.

Posted by: edstrick Jan 1 2006, 07:58 AM

Decepticon: "My attempt at merging earlier mapping with the most current Titan map."

I took the liberty of cropping a piece out of the map to point something ?cute? out. Has anybody else noticed the PlayBoy Bunny on Titan?

Posted by: Decepticon Jan 1 2006, 08:05 AM

OMG That is Hilarious!

Posted by: jmknapp Jan 1 2006, 01:31 PM

Move over, Mars bunny!

"Dance of the Seven Veils" is pretty hilarious too.



I was looking over some photos I took out the airplane window over the holiday, & found this one of specular reflections from small lakes around Pennsylvania I think. Wouldn't it be nice to see a return like this from Titan?

Posted by: Decepticon Jan 1 2006, 05:40 PM

Is the sun even strong enough to be seen? The suns beams need to go back up threw the haze.

Posted by: Bob Shaw Jan 1 2006, 10:13 PM

You might get a reflection from ice, too, or wet surfaces. The 1950s 'Mars Flash' has been explained as possibly being refraction (some strange mechanism - there was an article in S&T about five years ago) so it doesn't always need to be a situation where everything lines up at 90 degrees. Granite with water on it is quite blinding at times...

...presumably if light can get *down* in narrow wavebands, it can also get *up* too!

Bob Shaw

Posted by: JRehling Jan 1 2006, 11:31 PM

If we can see the difference between the dark and light terrains, then we should be able to see the difference between light terrain and a specular reflection -- unless it is very much more muted than you would expect of sunlight off liquid.

Posted by: belleraphon1 Jan 2 2006, 12:27 AM

All....

Should we open a specular reflection thread?

The modeling reports I have read all suggest that the team has full expectations of seeing a specular reflection, provided there are bodies of liquid at the specular point on each Titan flyby... that is why I got excited with those raws....

I can distinctly remember a reference, made by either Dr. Carolyn Porco or Dr. Elizabeth Turtle, to the modeling of a reflection through the haze and she even mentioned the researcher's name..... I believe this was at the NASA pre-Titan encounter press conference, either on that Friday the 2nd or Saturday the 3rd, in July of 2004, right after CASSINI SOI.... I've not been able to track down a transcript of that. I remember Dr. Porco saying that when the conference was over they were adjourning to the imaging lab, and if the press heard screaming it was because they caught the glint.

see..
http://www.spaceflightnow.com/cassini/040703titanpix.html

"But so far, the instruments have not detected reflections from the surfaces of lakes or small seas of liquid hydrocarbons many scientists believe must form in the ultra-cold environment.
But like the sun glint off rivers and lakes visible from airplanes on Earth, the reflections in question can only be seen in a small region of Titan, about 1 percent of the visible surface, based on the relative positions of the sun and Cassini."

http://www.planetary.org/news/2004/0706_No_Lakes_on_Titan_Too_Soon_to_Tell.html

"A specular reflection, or glint, occurs when a smooth, mirror-like surface is oriented so that it reflects sunlight directly at an observer. (Imagine the glinting reflection of a signaling mirror.)

For a spherical body like the Earth or Titan, there will always be one point on the sunlit part of the surface such that, if that point is covered by a smooth, mirror-like surface, spaceborne instruments should be able to see such a glint. Earth-orbiting spacecraft frequently see specular reflections from the Earth’s oceans. But throughout Cassini’s observations last week, no such glint was observed at any point on Titan.

Does this mean that there are no seas or oceans on Titan? “It’s too early to say that there is no liquid,” says Cassini imaging team member and University of Arizona researcher Elizabeth Turtle. “Titan is a completely alien surface. And understanding the surface is complicated by the fact that there’s an atmosphere in between [Cassini and the surface]. I think we need to spend more time trying to understand what we’re seeing.”
Turtle explained that since specular reflections were observed by the Earth-based Arecibo radio observatory, “It’s a big surprise that we didn’t see the specular reflection.” But there could be several reasons that Cassini didn’t see the reflection apart from a lack of seas or oceans. “It’s possible that the atmosphere is affecting how we can see the specular point. It may be that the atmosphere is decreasing the amount of signal. Or it may be that some of the features that we are seeing are low clouds. We’re just not real sure what we’re seeing on the surface yet.”

And

reference to equinoctial rain at the Huygen landing site latitudes

http://www.spacedaily.com/news/saturn-titan-05h.html

p.s trying to type though by black cat Moo's tail fur...... she believes that my keyboard is her butt warmer...

Craig

Posted by: BruceMoomaw Jan 2 2006, 09:49 AM

I imagine that the real explanation is that the specular reflections are coming off some of the mudflats or playa surfaces that seem to be scattered all over Titan; they're flat enough to produce a specular-reflection effect for long-wavelength waves like radio, but much too rough-surfaced to produce such a glint for short wavelengths like light.

Posted by: belleraphon1 Jan 2 2006, 01:59 PM

Good point, Bruce.....

That certainly fits the theorectical arguments (West et al 05 paper). But it does not fit some of the observations since the glints did not come from the dark 'playas'.

Huygens did a nice job at one small point on this big moon. But we have to be careful not to interpret that result too literally to all the light/dark expanses. How much geology would we understand of the Earth from one small point on it's surface.

So... the observations are of light areas that glint at radar wavelengths and not at infrared wavelengths... hmmmmmmmmmm

Craig