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Posted by: Decepticon Mar 12 2005, 02:56 PM

Takes place on 2005-Mar-31 Titan close flyby (T4) 2 520km


Very excited by this flyby. We get to see more east of the last 3 flybys. If I remember right its north of the area covered on SOI orbit insertion.
(Please correct me I may be wrong )




Here you can see cassini from above before the flyby. http://space.jpl.nasa.gov/cgi-bin/wspace?tbody=-82&vbody=1001&month=3&day=31&year=2005&hour=13&minute=00&fovmul=1&rfov=30&bfov=30&porbs=1&brite=1


And here is a view from Cassini just B4 closest approach. http://space.jpl.nasa.gov/cgi-bin/wspace?tbody=606&vbody=-82&month=3&day=31&year=2005&hour=19&minute=00&fovmul=1&rfov=30&bfov=30&porbs=1&brite=1

Posted by: Decepticon Mar 12 2005, 04:24 PM

I myself have a question about this flyby. Will Radar be used during this flyby?




On another note Cassini gets a Non targeted close flyby of Rhea One day before Titan. I hope they take pictures of Rhea on the way!

http://space.jpl.nasa.gov/cgi-bin/wspace?tbody=605&vbody=-82&month=3&day=30&year=2005&hour=12&minute=00&rfov=45&fovmul=-1&bfov=30&porbs=1&brite=1



We also get a close look at Enceladus on this pass!
http://space.jpl.nasa.gov/cgi-bin/wspace?tbody=602&vbody=-82&month=3&day=29&year=2005&hour=18&minute=00&rfov=30&fovmul=-1&bfov=30&porbs=1&brite=1

Posted by: volcanopele Mar 12 2005, 11:04 PM

To answer a few questions here:

1. No RADAR SAR coverage on this pass but they do get some radiometry and scatterometry on T4. The next RADAR SAR pass will be on T7 in September which covers the southern trailing hemisphere IIRC. On T8, there will be a RADAR SAR at 10S over the large bright region that Huygens landed just off the far eastern tip of. There maybe some low resolution coverage of the landing site during that pass. Despite not have RADAR SAR this time, ISS and VIMS will both have coverage over the eastern end of the T3 radar SAR swath, including the smaller of the two craters found by RADAR, at 600 m/pixel (ISS pixel scale). ISS and VIMS will also do joint observations at higher resolutions of an area of "cat scratches".

2. ISS coverage is of the equatorial and mid-northern latitude sub-saturnian hemisphere, complimentary to the T0 coverage of this face of Titan.

Posted by: remcook Mar 13 2005, 12:43 AM

...but would you be able to see anything from the north pole even if you would fly over it, since it is dark there? Not in visible I suppose. So we have to wait a while anyway to get high lattitude coverage.
right?

Posted by: Decepticon Mar 13 2005, 02:48 AM

Once again you came threw volcanopele.

Thanks for the info.

Posted by: Decepticon Mar 25 2005, 03:44 PM

I hope we can see this area better. Beside the sideways "H"

I wonder if this suspect crater is really not a crater.

I'm worried that the "crater" will be past the day terminal.

Posted by: volcanopele Mar 25 2005, 07:00 PM

I have posted a more complete description for T4 on my blog: http://volcanopele.blogspot.com/

I have also posted a plot from Titan24 that shows Cassini's view of Titan during our major mapping observation on this ecnounter. The dark circular feature you call a "crater", which doesn't look like a crater to me, will be visible on this pass.

Posted by: Bjorn Jonsson Mar 25 2005, 07:47 PM

I'm getting a bit confused about the flyby 'nomenclature'. I thought the upcoming Titan flyby was known as T5 and the recent Enceladus flyby as E4 but now I see these referred to as T4 and E1 ??

Posted by: volcanopele Mar 25 2005, 08:27 PM

don't worry, you are not the only who is confused:

There are three seperate nomenclature systems for Cassini Mission sequences (used to facilitate mission planning), orbit number, and flyby number. We are currently in S09 in mission sequence nomenclature. We are on Rev05 in orbit number terms (don't get me started on the fact we are actually on the 6th orbit, but on orbit number 5...). We are approaching T4, the 5th flyby of Titan. Confused yet?

Flybys are numbered in sequence from the first TARGETED flyby of a particular satellite. Since this month's Enceladus flyby was the first TARGETED Enceladus flyby, it was E1. Because of the extra orbit added at the beginning of the mission to fix Huygens' doppler shift problem, Rev01 and Rev02 became Rev0A, Rev0B, and Rev0C. Since this meant three Titan flybys instead of two as well, T1 and T2 became Ta, Tb, and Tc. The number for revs and Titan flybys was restored in February with Rev03 and T3.

So why were E03 and E04 used? I think this stems from two causes. First, the flyby in February, while very close, was not an official targeted flyby, so it didn't have an official flyby designation. So unoffially it was called E03 to correspond with the rev number. People then carried it on to the next flyby which was targeted and did have an official designation, but a lot of people used E04 instead to avoid confusion...that appears to have succeeded brilliantly

Posted by: Decepticon Mar 30 2005, 12:51 PM

http://www.planetary.org/news/2005/cassini_titan04_plan_0329.html

Posted by: Decepticon Mar 30 2005, 02:24 PM

Cassini page update, just in the nick of time.


http://saturn.jpl.nasa.gov/multimedia/images/image-details.cfm?imageID=1460

Posted by: volcanopele Mar 30 2005, 05:49 PM

I would have been done with it sooner but the program that creates those plots ....

Posted by: remcook Mar 31 2005, 07:40 AM

... and more and more of the vague parts of your map turn sharp at each flyby
when do you expect to have a (almost) full hi-res map of the surface?

Posted by: Decepticon Apr 2 2005, 02:21 AM

Hummm No pics yet?


Did something go wrong?

Posted by: Decepticon Apr 2 2005, 02:24 AM

Opps missed this....

Very excited now.

Posted by: volcanopele Apr 2 2005, 06:16 AM

Bon appatite:

http://saturn.jpl.nasa.gov/multimedia/images/raw/raw-images-list.cfm?browseLatest=0&cacheQ=0&storedQ=0

Posted by: dilo Apr 2 2005, 07:47 AM

Firt elaborations:
http://img123.exs.cx/my.php?loc=img123&image=w578082855vt.jpg
false color combination of images W00005780+82+85 (channels CB2/CL2+CB3/CL2+MT2/IRP0), re-scaled for matching distance at 118000Km.

http://img30.exs.cx/my.php?loc=img30&image=w0000576376stereo8li.jpg
Tentative stereo pair (crossed eye tch.) starting from W00005763+5776 (about 140000Km).

Follow a series of false color images of Titan edge from NarrowCam and different filters (warning: not sure about alignments!):
http://img30.exs.cx/my.php?loc=img30&image=n0003092425m3b35ux.jpg
http://img30.exs.cx/my.php?loc=img30&image=n309282930m3m1b0ua.jpg
http://img30.exs.cx/my.php?loc=img30&image=n309323334m3m1b9tz.jpg
http://img30.exs.cx/my.php?loc=img30&image=n309333435m3buv0oc.jpg

Posted by: Decepticon Apr 2 2005, 08:06 AM

Saturn behind titan.

http://saturn.jpl.nasa.gov/multimedia/images/raw/raw-images-details.cfm?feiImageID=36058

Posted by: Decepticon Apr 2 2005, 08:12 AM

I was convinced that Titan had a Huge crater beside that "H"

Even the images from VLT on earth hint it.

Posted by: volcanopele Apr 2 2005, 08:56 AM

I really doubt that it is a crater. The textures along its margins don't really suggest it.

Posted by: Sunspot Apr 2 2005, 01:25 PM

Is it just me or do the surface features appear to be a little more prominent in the latest images? Perhaps the contrast between features is a little higher on this part of Titan?

Cant wait to see some mosaics

Posted by: volcanopele Apr 2 2005, 02:09 PM

Don't worry, you will. It took an all-nighter, but I finally got it done...

Posted by: Decepticon Apr 2 2005, 02:54 PM

Little tease...

Posted by: alan Apr 2 2005, 03:04 PM

Saturn seen through Titan's atmosphere
http://saturn.jpl.nasa.gov/multimedia/images/raw/casJPGFullS09/W00005811.jpg

Even more layers than last time
http://saturn.jpl.nasa.gov/multimedia/images/raw/raw-images-details.cfm?feiImageID=36240

Posted by: dilo Apr 2 2005, 10:39 PM

I tried to make some context identifications of Narrow angle images; one still not recognized (someone can try). Could be useful for mosaic activity...
http://img224.exs.cx/my.php?loc=img224&image=identifications0tj.png

As a bonus, I add also a couple of color compositions; first one is "true "RGB taken from wide angle , second one is a false-color detail of hazes using Uv+two IR channels. Bye.
http://img224.exs.cx/my.php?loc=img224&image=w000059414243rgb5ys.jpg
http://img224.exs.cx/my.php?loc=img224&image=w0000586061549ca.jpg

Posted by: volcanopele Apr 2 2005, 11:31 PM

That frame, 30978, is just to the lower left of 30994. That is a bit of a bad stretch...

Posted by: Decepticon Apr 3 2005, 02:59 AM

Ciclops Update....

http://ciclops.lpl.arizona.edu/view_event.php?id=18


That first image looks very interesting. I can almost make out little vein like channels.

Posted by: dilo Apr 3 2005, 09:28 AM

Thanks, volcanopele. I do not understand wath you mean "a bit of bad stretch"... anyway, here my tentative mosaic, rescaling images based on distance and superimposing them to enhanced version of W00005777 (contrast/luminosity differences are deliberlately left different in order to see all detils in each narrow-angle image):
http://img225.exs.cx/my.php?loc=img225&image=mosaic3zq.png

Posted by: Decepticon Apr 5 2005, 01:02 AM

Wow^^

When is the press release?

Posted by: volcanopele Apr 5 2005, 04:25 AM

Sometime this week. Hopefully...I haven't been too impressed with JPL and their speed to put out press releases of late.

Posted by: alan Apr 5 2005, 08:50 PM

New territory
http://ciclops.lpl.arizona.edu/view.php?id=992

Posted by: Decepticon Apr 5 2005, 09:00 PM

Breathless.... And that's a low res pic.

Posted by: cIclops Apr 5 2005, 09:06 PM

There are a lot of bight pixels in that image ... CCD damage?

Posted by: volcanopele Apr 5 2005, 09:46 PM

No, just cosmic ray hits. Usually we just filter those out, but maybe Daren forgot or for some reason was detrimental to the sharpening procedure he ran. I guess I should have asked about that before it was released...

Posted by: alan Apr 5 2005, 10:09 PM

When the imaged is stretched like that it looks like there are a couple of plumes visible

http://s05.imagehost.org/view.php?image=/0999/plumes.jpg

I think the lower one was imaged by the radar on T3

Posted by: volcanopele Apr 5 2005, 10:32 PM

You never know..... *whistles*

Posted by: Decepticon Apr 6 2005, 12:02 AM

Currently titans southern hemisphere is visible.

When does the northern hemisphere come into full view?

Posted by: Gsnorgathon Apr 6 2005, 06:57 AM

Posted by: EckJerome Apr 6 2005, 05:47 PM

I concure with...

My oh my, it's starting to look like Titan is one active world!

Posted by: volcanopele Apr 6 2005, 06:17 PM

okay, let me pull you guys back. We don't know that they're active plumes (and cryovolcanism is only ONE working theory, the other that it is a crater splotch, a la Venus). We will see this same area again next week and we should know then. If it isn't active, my feeling is that these are plume deposits a la Triton.

Posted by: Sunspot Apr 7 2005, 09:05 AM

They're pretty slow at updating the RAW images lately....

Posted by: Decepticon Apr 8 2005, 12:27 AM

I'm hoping for something Friday.

It's been a full week now.

Posted by: volcanopele Apr 8 2005, 01:08 AM

there also hasn't been to many images taken since the T4 flyby. I think I have seen 4 since then. But you're right, those 4 should still have shown up.

Posted by: dilo Apr 8 2005, 09:03 AM

One of the few images is a beautiful RGB portrait of Tethys and Rings. Here the combined image with corresponding geometry (from Celestia software):
http://img70.exs.cx/my.php?loc=img70&image=anelli0ru.jpg

Posted by: alan Apr 8 2005, 07:45 PM

Steve Albers has updated his map of Titan
http://laps.fsl.noaa.gov/albers/sos/sos.html
and some of the other moons too

Posted by: tedstryk Apr 8 2005, 08:10 PM

http://ciclops.lpl.arizona.edu/view_event.php?id=20

Check out the new images - ISS is starting to actually show features that look like something!

Posted by: OWW Apr 8 2005, 08:49 PM

Excellent. Some thoughts comparing this mosaic with the T3 radar swath:

- Again, all dune-covered areas in the radarswath are dark in the ISS image.

- The 'dark cloud' is also dark in the radar image! Radar shows a circle in the middle of that dark splotch, but if it was a crater, shouldn't the ejecta blanket be radarbright, not dark? Maybe it is an evaporating lake or Io-like caldera with plume?

Can't wait until the next flyby...

Posted by: volcanopele Apr 8 2005, 10:56 PM

You can see my speculation on that dark streak in my blog, but my first interpretation and my favored interpretation is that it is a site of methane outgassing. Also, RADAR doesn't show the same dark streak in the shape that we do, so I have speculated that RADAR may actually be looking through the dark deposit to the material below, at least in the distal regions. Nearer the source region, there is a pretty good coorelation.

Posted by: volcanopele Apr 8 2005, 11:37 PM

Cool. My only recommendation would be for Steve to include the Saturn-shine image of Iapetus, http://ciclops.lpl.arizona.edu/view.php?id=708, into his map. Maybe even use the new map of Titan that was recently released and combine that with the T4 WAC he used.

Posted by: Sunspot Apr 9 2005, 12:12 AM

WOW.......thats got to be a plume of some sorts.....or debris from a plume..

Posted by: volcanopele Apr 9 2005, 12:16 AM

I don't think we need to invoke that it is active, only that it is a thin enough deposit to be hidden from RADAR in the distal regions of the deposit, which as long as it doesn't contain ammonia, maybe several 10s of meters. if it contains ammonia, we may be talking meters. In addition, you can just make out a dark spot in the area were we see this streak on my map released last month. The data for that area of Titan came from images taken in June, prior to SOI.

Posted by: Sunspot Apr 9 2005, 12:44 AM

I just thought......Is the feature aligned with the prevailing wind direction? If it's not, I guess it could be something else?

Posted by: volcanopele Apr 9 2005, 12:47 AM

well, that's a good question. The prevailing wind is west-east but Huygens showed a boundary layer at 5 km and seems to indicate that surface winds may not match this east-west directionality. So what ever formed this managed to stay below the boundary layer, perhaps another case for this being due to geysers rather than cratering.

Posted by: Decepticon Apr 9 2005, 03:39 AM

VP will the gaps in between the High Res Mapping be filled on the next flyby?

Also is there a High Res mosaic global map coming soon?


I also wanted to say you work is AMAZING. Years from now I can share this work with my son and say I posted with you online!

Posted by: volcanopele Apr 9 2005, 09:50 PM

Our next flyby has some higher resolution imaging but only over a few point on the visible surface, so it won't do much to fill in the gaps (caused by a trajectory tweak that pulled apart our mosaic for T4). In terms of a map, I will start work on completely redoing the map in the next month and hope to have it done by mid-May. When it will be release, it is too soon to say.

Posted by: Sunspot Apr 12 2005, 11:46 AM

Hi volcanopele, has that image of the possible plume generated much interest or discussion among Cassini imaging scientists?

Posted by: alan Apr 13 2005, 11:47 PM

Iapetus map has been updated with saturnshine images
http://laps.fsl.noaa.gov/albers/sos/sos.html

Posted by: Decepticon Apr 14 2005, 12:02 AM

^^Excellent!!!