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Posted by: ngunn Oct 29 2009, 07:08 PM

The rev 121 Rhea nontargeted flyby is discussed in a http://www.unmannedspaceflight.com/index.php?showtopic=6315 - moderator

Mission Description double bill:
http://saturn.jpl.nasa.gov/files/20091102-21_enceladus_mission_description.pdf

Posted by: elakdawalla Oct 29 2009, 09:42 PM

Holy smokes, whose job is it going to be to assemble THIS mosaic? Is it you, Jason? Looks gnarly.

Posted by: volcanopele Oct 29 2009, 09:49 PM

It's what I do, shouldn't be too difficult. It is just a clear filter mosaic.

Posted by: JohnVV Oct 30 2009, 03:35 AM

for someone experanced it won't be a problem ,
i am just learnning how to use a control network for isis3


OT) a bit off topic but dose anyone have some links for manuals for isis besides the links here
http://isis.astrogeology.usgs.gov/index.html
https://isis.astrogeology.usgs.gov/IsisSupport/index.php

Posted by: nprev Oct 30 2009, 05:20 AM

That's gonna be a great set; lots of terra inexplorata, as it were.

Posted by: Juramike Oct 31 2009, 04:06 PM

Latest global map of Enceladus was released (pre-flyby):

http://photojournal.jpl.nasa.gov/catalog/PIA11680

Posted by: JohnVV Oct 31 2009, 08:53 PM

and the last pds release " SE_500K_0_0_SIMP.IMG 17-Sep-2009 07:39 99M "
http://pds-imaging.jpl.nasa.gov/data/cassini/cassini_orbiter/coiss_3002/data/images/

Posted by: eoincampbell Nov 1 2009, 04:05 AM

Should we expect images worthy of the swear-jar this around?

Posted by: ngunn Nov 1 2009, 07:59 PM

This one's not bad for starters:
http://saturn.jpl.nasa.gov/multimedia/images/raw/casJPGFullS54/W00060947.jpg

Posted by: Stu Nov 1 2009, 10:09 PM

Wow! That's one hell of a plume!!!

Posted by: nprev Nov 2 2009, 12:19 AM

I might have missed it in the mission description, but will Cassini be oriented dish-first along the trajectory during the plume flythrough? Not sure if they feel that any precautions are required or not.

Posted by: john_s Nov 2 2009, 03:07 AM

Nope, the mass spectrometer and dust instruments will be facing forward to get the best possible sampling of the plume. We're confident by now that these passages are safe, especially as the speed of this passage is much slower than last time we flew through. The question we're anxious to learn about on this flyby (other than the science results of course) is whether the plume is affecting the spacecraft pointing stability enough to require use of the attitude control thrusters in future similar flybys. If we can get away without thrusters in future close plume flybys, we'll be able to use the flybys to measure gravity and thus investigate the interior structure under the tiger stripes, and we will plan on doing so next Spring, on orbit 131. If we have to continue to use thrusters in the plume we'll use the orbit 131 flyby for more plume sampling instead, because the thrusters interfere with the gravity measurements.

Posted by: nprev Nov 2 2009, 04:44 AM

Thanks, John. I suspected as much given the emphasis on direct sampling; appreciate the reassuring confirmation!

Posted by: ustrax Nov 2 2009, 08:09 PM

I am sure I have missed this class...for when are we expecting the images of the flyby to hit the web?

Posted by: jasedm Nov 2 2009, 08:27 PM

Next 24 hours I would imagine...

Posted by: Sunspot Nov 2 2009, 08:47 PM

I got this email from the ciclops website:

A select few images will probably appear there first.

Posted by: Anne Verbiscer Nov 2 2009, 09:23 PM

The last two pages of JPL's mission description document (a link is found on http://saturn.jpl.nasa.gov/mission/flybys/enceladus20091102/) provide the playback tables for all data acquired during the E7 (today) and E8 (Nov. 21) flybys. When the images (entries with black background, beginning with "ISS" in those tables) get posted on JPL's raw web site is hard to say.

According to the data playback table, the first two observations of Enceladus' plumes at extremely high phase angles (>165 degrees, observable only because the spacecraft was safely hidden from the Sun - in eclipse behind Saturn - at the time they were taken) should already be on the ground.

Posted by: Bjorn Jonsson Nov 3 2009, 01:16 AM

WOW!

http://saturn.jpl.nasa.gov/photos/raw/rawimagedetails/index.cfm?imageID=205346
http://saturn.jpl.nasa.gov/photos/raw/rawimagedetails/index.cfm?imageID=205345
http://saturn.jpl.nasa.gov/photos/raw/rawimagedetails/index.cfm?imageID=205347
http://saturn.jpl.nasa.gov/photos/raw/rawimagedetails/index.cfm?imageID=205344

Only these four images so far - should soon be a lot more.

Posted by: Hungry4info Nov 3 2009, 01:20 AM

Wow is right.

Posted by: mhoward Nov 3 2009, 01:20 AM

** clink, clink **

Posted by: ElkGroveDan Nov 3 2009, 01:39 AM

Oh my.

Posted by: nprev Nov 3 2009, 01:40 AM

...<clink!>

Edit: More on the site as we speak: serious http://saturn.jpl.nasa.gov/photos/raw/rawimagedetails/index.cfm?imageID=205381!

Posted by: Hungry4info Nov 3 2009, 01:48 AM

Plumes!

http://saturn.jpl.nasa.gov/photos/raw/rawimagedetails/index.cfm?imageID=205381
http://saturn.jpl.nasa.gov/photos/raw/rawimagedetails/index.cfm?imageID=205377
http://saturn.jpl.nasa.gov/photos/raw/rawimagedetails/index.cfm?imageID=205376

Posted by: nprev Nov 3 2009, 01:52 AM

205377 is amazing. I count 5 discrete large plumes; who knows how many smaller ones there may be.

Posted by: Hungry4info Nov 3 2009, 02:08 AM

Not sure what this is showing, if anything useful, but here's a string of the plume images (animation).

Posted by: volcanopele Nov 3 2009, 02:11 AM

Versions of a few images without jpeg compression artifacts:

http://ciclops.org/view/5935/Enceladus_Rev_120_Flyby_Raw_Preview_2

Posted by: nprev Nov 3 2009, 02:27 AM

That made a huge difference, Jason, thank you! I'm upping my discrete plume count to no less than 14.

Posted by: volcanopele Nov 3 2009, 04:42 AM

http://saturn.jpl.nasa.gov/photos/raw/rawimagedetails/index.cfm?imageID=205344

Just so you all know, while the image is cropped from apparent data dropouts (which could be recovered during the next playback), you aren't missing much. Maybe another 50-100 lines of surface while the rest is space.

Posted by: Juramike Nov 3 2009, 05:21 AM

RGB combo of Enceladus images (R=IR1; G=Red; B=Blue) with the bright crescent filled in with a lower exposed portion of a RED filtered image (N00145932).

(and lotsa playing around with contrast levels)

Posted by: Stu Nov 3 2009, 06:20 AM

Good grief!!! What a sight to wake up to! I'm out to work in a few minutes, walking through curtains of lashing rain, and will arrive there soaked to the skin, but I don't care... look at that: a dozen or more plumes on Enceladus... just a magical time to be here isn't it?

Is this Enceladus silhouetted against the rings?

http://saturn.jpl.nasa.gov/multimedia/images/raw/casJPGFullS54/N00145342.jpg

If so, that's a heck of an image, too...

Posted by: nprev Nov 3 2009, 06:48 AM

Yes it is, Stu, and looking at it more closely I realize that it's even more interesting than I thought at first glance. Notice the apparent ring refraction around the edges of Enceladus, and the fuzzy dim apparent refraction of 'ringshine' all over the top (assuming that's the south polar region) of the moon.

The plumes seem to sustain a localized atmosphere dense enough to produce these effects. That's wild!!!

Posted by: Hungry4info Nov 3 2009, 09:16 AM

I'm confused.

There seems to be no light shining on that hemisphere, so either the sun is directly behind it or it is in eclipse by Saturn. Since they are taking it safe with the camera, surely the sun isn't directly behind Enceladus. And no plumes are visible, suggesting no light is getting anywhere close to Enceladus. So... it's Enceladus in Saturn's shadow? And if so, why is it mixed in with the images from this approach? Enceladus well over the illuminated Saturnian hemisphere at the time of the flyby.

Posted by: volcanopele Nov 3 2009, 09:27 AM

The images in the JPL Raw Images page for this flyby are out of order. Those eclipse shots were actually taken first, then the images with clearly prominent plumes, then the dark frames currently the latest images on that page (taken shortly before C/A), then the few great shots of the south polar terrain boundary, and finally the Tethys images.

Posted by: belleraphon1 Nov 3 2009, 12:44 PM

WOW!

At work and just had my first chance to look at these.

Enceladus has gorgeous plummage (Bad pun)

A lot of plume detail to be had here.

Beautiful!!!!

Craig

Posted by: ugordan Nov 3 2009, 05:32 PM

A RGB view with F ring backdrop and one of the saturnlit, small rocks wandering into the scene. Very artifacted stuff, this might be a beauty once calibrated data is available.

Posted by: elakdawalla Nov 3 2009, 05:47 PM

Looks like it's Prometheus. Cool!

Posted by: mgrodzki Nov 3 2009, 05:50 PM

been a long pause… is this all of them or are there surface shots to look forward to for closest approach?

Posted by: volcanopele Nov 3 2009, 06:03 PM

There hopefully will be 1 or 2 more BOTSIMs (NAC/WAC combos) that will come down in this cleanup playback today. Images might show up ~noon MST. So if they don't show up in the next hour or two, that might be it.

Posted by: jasedm Nov 3 2009, 07:40 PM

Could the pointing have been a little off? - there are 16 NAC/WAC frames from a range of ~11,000km showing just background stars. Perhaps the plume passage exerted some unexpected drag on Cassini?

Posted by: illexsquid Nov 3 2009, 07:48 PM

Those plume shots are spectacular. The level of fine detail is much higher than what I recall from previous Enceladus encounters. Can someone with more knowledge than me comment on this? Is it a consequence of higher resolution? A better viewing angle? Better tracking? Or has the Cassini crew just learned from past encounters how to optimize exposures for the plumes?

Posted by: S_Walker Nov 4 2009, 09:09 PM

Here's an image created from 5 of the raw shots captured this weekend. The 5 images taken through CL1 and 2 filters:
N00145409, N00145408, N00145403, N00145398, and N00145388 were registered then combined in an HDR program to try to bring out some of the structure in the plume, I then colorized the image using a red, blue, and clear filtered image.

Enjoy.

Posted by: ngunn Nov 4 2009, 10:49 PM

That is superb. The yellowish saturnshine in particular turns an image into an experience. Thanks for sharing it.

Posted by: S_Walker Nov 4 2009, 11:34 PM

Those look more like cosmic ray hits than stars. Perhaps they were shooting some new calibration frames; in this case, dark exposures.

Posted by: S_Walker Nov 4 2009, 11:37 PM

I think it's because none (or very little) of Enceladus is illuminated, so longer exposures could be used to record the plumes. If it were, blooming from the bright surface of the moon would ruin the faint details in the plume.

Posted by: Floyd Nov 5 2009, 12:39 AM

volcanopele or other Cassini team members: Can you say anything about how Cassini did flying through the plumes? It seems that thrusters did not bring craft back to proper orientation for BOTSIM images. This would imply that reactions wheels would definitely not be enough to keep craft oriented?

Posted by: volcanopele Nov 5 2009, 12:55 AM

Not sure. Those BOTSIMs were just taken earlier than I thought they would be, though this was expected.

Posted by: nprev Nov 5 2009, 01:41 AM

Jason, has anyone set an upper limit on the 'temporary' surface pressure in the south polar region from the localized atmosphere produced from these apparently continuously active plumes? The limb refraction & scattering of F-ring-shine to some degree all around the pole in http://saturn.jpl.nasa.gov/multimedia/images/raw/casJPGFullS54/N00145342.jpg really intrigues me.

I'm guessing that the peak surface pressure at the densest point in this region is WAY less than a millibar (probably less than tens of microbars), but the refraction in this image is really striking.

Posted by: brellis Nov 5 2009, 02:07 AM

*steps out from the crowd of lurkers*

If the first mystery is how such a small moon could have oceans and emit geysers, the second (for me) is how is the material recycled to replenish the oceans? The returning material gives Enceladus a bright surface color, but then what happens? How does the ice get back under the surface? Is there a related process when the stripes break open?

Thanks, and I love reading the threads here!

Brad

Posted by: john_s Nov 5 2009, 02:48 AM

I don't believe there's any noticeable refraction of the ring light in this image- just the plumes near the pole, and an ultra-thin sunlit crescent on the right side of the disk, and a scattering of compression artifacts. Certainly the plume atmosphere is not dense enough to generate significant refraction.

I also don't believe there were any significant pointing anomalies due to the plume passage. There should be an announcement soon about the decision regarding the use of thrusters on orbit 130- I'll check if we're allowed to talk about it here :-)

John

Posted by: nprev Nov 5 2009, 05:35 AM

I might be getting spoofed by the curvature of Enceladus' darkened limbs. The refraction I thought I saw (and, frankly, it looks much less pronounced to me now) was a slight distortion of the F-ring right at the point where it disappears behind Enceladus on each side.

May well be a JPEG artifact if it's anything at all besides my imagination; I confess my ignorance of those!

Posted by: jasedm Nov 6 2009, 09:46 PM

No additional NAC images of enceladus have shown up on the raws page since the flyby - it seems there must have been a problem of some sort with the near-encounter mosaic imagery.
Shame, but you can't win 'em all
Oh well, the next encounter's less than three weeks away....

Posted by: volcanopele Nov 6 2009, 09:59 PM

There was no mosaic imagery this time around planned. All the mosaics are planned for the next encounter.

Posted by: jasedm Nov 6 2009, 10:03 PM

My mistake - thanks jason, I look forward to those.

Posted by: Floyd Nov 7 2009, 12:09 AM

I was confused as well. My previous post was in response to what I thought were missing mosaic images. Glad to realize that they will show up in three weeks.

Posted by: scalbers Nov 7 2009, 01:25 AM

As I recall the next flyby is the one that shows more new terrain at higher resolution - should be pretty neat.

Posted by: HughFromAlice Nov 8 2009, 06:26 AM

Great - enjoyed it ......Keep posting

It is really amazing that Cassini is being flown through these plumes. I find these very powerful images. They really move me.

I am away from home on the East Coast of Aus in Newcastle at a family enagement party but took time out and had fun taking a bit of time out doing this interpretation on my laptop.



Did a fair bit to get the Saturnshine to show up and get more details on those fantastic plumes. Can't pretend it's scientifically accurate. I more wanted to get a powerful impression without straying too far from the reality. My laptop has a horrible screen so I hope it turns alright for others.

Posted by: Littlebit Nov 13 2009, 08:59 PM

Like it, Hugh from Alice!

The plumes turn into a city in celibration! I suspect some jpeg artifacts are creeping in, but it makes nice art.

These are some of the best raw images, ever.

Posted by: HughFromAlice Nov 14 2009, 10:19 AM

Thanks. I like the dichotomy of in some pics going for effect and in others going for accuracy. That's the fun of blogging!! But not enough hours in the day.

Yes, fantastic raw images, great space craft and team, plus brilliant skeet shoot technique!!

Posted by: ngunn Nov 20 2009, 11:38 AM

Quote from the flyby page for today:
"NASA's Cassini spacecraft will fly by Saturn's moon Enceladus this weekend for a last peek at the intriguing 'tiger stripes' before winter darkness blankets the area for several years."

Got me thinking what will the tiger stripes look like after the sun sets. Might there be some kind of luminescence associated with the plume activity?

Posted by: ugordan Nov 20 2009, 11:41 AM

Probably nothing that wouldn't already have been discovered in many long exposure, eclipse shots during the outbound leg on a couple of flybys.

Posted by: ngunn Nov 20 2009, 12:40 PM

Right, thanks, clearly nothing on a spectacular scale. I was thinking of a very localised effect, maybe confined to the 'throats' of the vents where presumably collisions and friction occur. With resolution comparable to the 30m expected today maybe it's still an outside possibility for the future.

Posted by: Bjorn Jonsson Nov 21 2009, 01:19 PM

Wow:

http://saturn.jpl.nasa.gov/photos/raw/rawimagedetails/index.cfm?imageID=207300

This is a WA image. The thumbnails on the Cassini raw image site are broken but the images are there.

Highly fractured terrain:

http://saturn.jpl.nasa.gov/photos/raw/rawimagedetails/index.cfm?imageID=207285

Extremely rough terrain at high resolution, I wonder if this is due to recent/ongoing geological activity:

http://saturn.jpl.nasa.gov/photos/raw/rawimagedetails/index.cfm?imageID=207273

WOW, WOW, WOW!!! Hi-res plumes:

http://saturn.jpl.nasa.gov/photos/raw/rawimagedetails/index.cfm?imageID=207263

Posted by: Bjorn Jonsson Nov 21 2009, 01:23 PM

Actually I can't resist posting a plume image here. These are by far the best and most spectacular plume images Cassini has obtained:

Plumes from a distance of less than 10,000 km!

Posted by: Stu Nov 21 2009, 01:26 PM

Holy frak...!!!

Best get the swear jar ready folks...

Posted by: Bjorn Jonsson Nov 21 2009, 01:28 PM

This one shows backlit plume material silhouetted against the shadowed surface along the fractures so it is very easy to determine exactly where the plumes originate:

Of the many spectacular images Cassini has returned these are definitely near the top.

Posted by: belleraphon1 Nov 21 2009, 01:31 PM

OH WOW ....Bjorn

the images are beyond what I expected! Plumes and all that fracturing...

Look at these
http://saturn.jpl.nasa.gov/photos/raw/rawimagedetails/index.cfm?imageID=207271

http://saturn.jpl.nasa.gov/multimedia/images/raw/casJPGFullS55/N00146728.jpg

http://saturn.jpl.nasa.gov/photos/raw/rawimagedetails/index.cfm?imageID=207262


Craig

Posted by: Bjorn Jonsson Nov 21 2009, 01:37 PM

I'm getting the impression that this must be the most 'photogenic' Enceladus encounter so far despite having looked at only a few images.

Just WOW!!!

Posted by: tedstryk Nov 21 2009, 01:55 PM

http://saturn.jpl.nasa.gov/multimedia/images/raw/casJPGFullS55/N00146709.jpg has left me almost unable to use whole words. Wow!!!

Posted by: Floyd Nov 21 2009, 01:58 PM

Bjorn, I totally agree--these are some of the best images of the mission, and that really says a lot. Wow!

Posted by: remcook Nov 21 2009, 02:14 PM

Yup, swear jar time! Amazing, really amazing! Those plumes coming from the dark into the light...wow

Posted by: ugordan Nov 21 2009, 02:19 PM

Oh, my, these images are simply wonderful! Here's a rough cross-eyed stereo view of the plumes.

Anyone prefer a red/blue anaglyph instead?

Posted by: Hungry4info Nov 21 2009, 02:24 PM

Meh... I've seen better.

More seriously.
HOLY CRUD!
That is so spectacular! I never thought you would ever be able to actually point to and say "That is the plume source" from Cassini images. This is amazing! Wow... just absolutely gorgeous. You can even trace the scarps on the dark-side of the moon. These images are incredible!

Edit:
Wow! Look at that canyon!
http://saturn.jpl.nasa.gov/photos/raw/rawimagedetails/index.cfm?imageID=207280

Posted by: ugordan Nov 21 2009, 02:38 PM

A great stereo view of one of the stripes, 2.6 and 3 thousand km frames:

Posted by: ugordan Nov 21 2009, 03:01 PM

And an anaglyph of frames from 2 and 2.3 thousand km frames:
http://i108.photobucket.com/albums/n15/ugordan/enceladusstripe2_2.jpg

Posted by: Stu Nov 21 2009, 03:02 PM

Wow...

Posted by: ngunn Nov 21 2009, 03:16 PM

Wonderful sights! Hats off to the Cassini team, and thanks to Stu and Gordan for the 3Ds. (But Stu, I'm having to reverse the specs to see the same as Gordan's cross-eye version.)

EDIT: I'm also suffering from a rush of blood to the head as a result of balancing upside down to get a 'normal' view of that plumed landscape in post 65.

Posted by: Sunspot Nov 21 2009, 03:20 PM

Those plume images !!!!!!!!

Posted by: Mariner9 Nov 21 2009, 03:25 PM

I was a bit depressed before the flyby knowing that this was likely the last time a spacecraft would be able to see the Tiger Stripes in the next 20 years.


Then I saw the images where I could see the plumes emerging from the surface ..... well, still sorry that this is the last of the surface images of the south pole, but what a great way to go out!

Posted by: floron Nov 21 2009, 03:42 PM

here's a red/blue anaglyph of the plumes, with the contrast tweaked just a wee bit.

Posted by: Stu Nov 21 2009, 03:55 PM

B*r! Thanks for pointing that out, corrected version here...

http://twitpic.com/qdbuc

Posted by: eoincampbell Nov 21 2009, 03:57 PM

Fantastic work by the Cassini team to bring us those astounding pictures. What a place!

Posted by: elakdawalla Nov 21 2009, 04:28 PM

WOW!! THanks for the eye-popping stereo, guys!

Posted by: mhoward Nov 21 2009, 05:00 PM

This is what red-blue glasses were made for. Jaw-dropping stuff. Thank you!

Posted by: machi Nov 21 2009, 05:11 PM

Stereo images are simply amazing!

Posted by: jasedm Nov 21 2009, 05:54 PM

I'd almost forgotten about this encounter (unusual for me, as I am normally very well-aware of Cassini's upcoming treats) There seems to have been much less fanfare with this encounter, but going by the images, it has to be the best yet.
Simply stunning! many congratulations to those that plan the observations - seems to have all gone to plan.
Rhea encounter up next too - maybe we'll get a little more insight into that equatorial band on this flyby.
Great times.....

Posted by: imipak Nov 21 2009, 07:07 PM

<Ob StarWars reference>

Astounding images, and at 17200mph!

Posted by: ugordan Nov 21 2009, 07:19 PM

This flyby certainly set new standards for awesome.
http://saturn.jpl.nasa.gov/photos/raw/rawimagedetails/index.cfm?imageID=207423
It's like flying through the fog! Also, check out the moon's limb contour!

Posted by: scalbers Nov 21 2009, 07:27 PM

Amazing to see Enceladus' shadow appear to lift off in several locations, and to see the limb of the dark side as Gordan mentions. I wonder how these images showing localized plumes might be able to be correlated with CIRS measurements to help derive temperatures.

Posted by: Sunspot Nov 21 2009, 07:36 PM

Would love to have seen the reaction from the science teams when these images came down

Posted by: Stu Nov 21 2009, 07:49 PM

Just... beautiful...

Posted by: nprev Nov 21 2009, 08:14 PM

<yawn><wakes up, turns on computer, goes to UMSF>.... <CLINK!> ....THUD!!!!! <passes out again!>

Good grief. These are all just ridiculously amazing images. I gotta digest this. Think one of the overhead shots actually showed a fumarole!

Posted by: Tman Nov 21 2009, 08:17 PM

The longer the mission the better the images...

Posted by: belleraphon1 Nov 21 2009, 08:35 PM

Ya know, Stu.... I do not know if there are words for these moments but I hope you find them.

When CASSINI acheived Saturn orbit back in 2004, I never dreamed we would see this. The Universe is so big. We are so small. But we can manage missions like these. Just makes me wonder what else is waiting for us out there!

Glorious!

Craig

p.s Hope you are well!

Posted by: Juramike Nov 21 2009, 08:39 PM

Mosaic made of the initial images N00146699, N00146701, and N00146702. Dropouts removed, and an underlayer of wide angle W00061502 used as background. Much leveling, and dodging/burning/and blurring to blend int the dropout areas.

-Mike

Posted by: volcanopele Nov 21 2009, 08:55 PM

Just in case you are all wondering: The E-8 playback ended about 3 hours ago ERT. The rest of the data I presume will be carried over to the next playback which begins, Earth-receipt time, in about 40 minutes or so. The gap is the result of the Rhea non-targeted encounter. Now, I am not sure either whether this playback will be a real-time stream like the one this morning was. I think we should know in about an hour. If it isn't, Rhea and Enceladus images will show up around midnight MST (~10-11 hours from now)

Posted by: belleraphon1 Nov 21 2009, 09:04 PM

I was wondering. Thanks, Jason, for the info.

I have STS-129 NASA TV coverage in one window, downloaded CASSINI images in another and then this forum.

space heaven

Craig

Posted by: jasedm Nov 21 2009, 09:14 PM

Don't want to appear ungrateful, but Cassini passed Calypso within 40,000km en-route to Rhea - no chance I suppose for a couple of snapshots of the moon? Perhaps it was in eclipse at the time, or pointing constraints ruled out any images based on priorities....
Just askin'....

Posted by: dilo Nov 21 2009, 09:40 PM

Sirs, I still need to fully recover from such pleasant shock.... The multiple plumes emerging from darkness and "tracing" the faults are simply breathtaking!
In the meantime I made this mosaic where I identified contest of images 6002_14142 (WA), 6004_14140 (NA) and 5999_14130 (NA):

In fact this sequence could be used to make a real "bird fly" over such features! (note that I rotated 180° all pictures and I cropped in order to almost eliminate the very disturbing histogram on one side of all ciclops pictures).

Posted by: NickF Nov 21 2009, 10:27 PM

Truly wonderful images. Thanks to those that have taken the time to present some of the highlights to us on the forum.
(and congrats to everyone at Team Cassini of course!)

Posted by: Hungry4info Nov 21 2009, 10:31 PM

More plume images, though not quite as amazing.
http://saturn.jpl.nasa.gov/multimedia/images/raw/casJPGFullS55/N00146846.jpg

http://saturn.jpl.nasa.gov/multimedia/images/raw/casJPGFullS55/W00061504.jpg


Enceladus + ring
http://saturn.jpl.nasa.gov/multimedia/images/raw/casJPGFullS55/W00061499.jpg

Traditional view of the plumes, + Saturn
http://saturn.jpl.nasa.gov/multimedia/images/raw/casJPGFullS55/W00061501.jpg

http://saturn.jpl.nasa.gov/multimedia/images/raw/casJPGFullS55/W00061500.jpg

Posted by: scalbers Nov 21 2009, 10:47 PM

This has some interesting Solar + Saturnian lighting effects (note from the Nov 2 encounter - and I see it was posted before):

http://saturn.jpl.nasa.gov/multimedia/images/raw/casJPGFullS54/N00145397.jpg

Posted by: Paolo Nov 21 2009, 11:27 PM

from a purely aesthetic point of view, these are my favorite images of the encounter

Posted by: ngunn Nov 21 2009, 11:36 PM

[quote name='Stu' date='Nov 21 2009, 07:49 PM' post='150618']
Just... beautiful...
/quote]

That picture, in my view, is the best version yet of any of these images. However it appears to be left-right inverted relative to others posted here. Is it just me? I know it's late . . .

Posted by: Ron Hobbs Nov 21 2009, 11:48 PM

I just have to add my gratitude to the Cassini Team and to all of the imaging magicians on this site.

As well as my speechlessness. What a time to be alive.

Ron

Posted by: Astro0 Nov 22 2009, 12:54 AM

Just inspirational images...wow!
Here's the artists view. Enjoy.

Posted by: Juramike Nov 22 2009, 02:01 AM

Snowy ridges of Enceladus:

I took the Cassini Raw N00146709.jpg image, and used the Filter/Video/Deinterlace (even fields, interpolate) filter in Photoshop.

This image was acquired from a distance of 1,855 km.

-Mike

Full Res TIFF (3 Mb - and it's well worth it!) here: http://www.flickr.com/photos/31678681@N07/4123688100/

[EDIT: original image and technique changed based on suggestion below, images on flickr and here updated.]

Posted by: elakdawalla Nov 22 2009, 02:10 AM

The every-other-line truncation can be fixed quickly in Photoshop by using the Filter -> Video -> De-interlace. You can get a quick and dirty result that way. To refine it a bit, just select the part of the image that has the truncation problem and run the filter on that part.

Posted by: Juramike Nov 22 2009, 02:16 AM

Well, by golly, it does. And it's a much better result than the one above....

*sigh*

Posted by: jgoldader Nov 22 2009, 02:28 AM

This one

http://saturn.jpl.nasa.gov/multimedia/images/raw/casJPGFullS55/N00146706.jpg

looks like really heavy rime ice in a freezer that's been too long between defrostings. That texture... it looks too amazing to be real. So beautiful it almost makes you want to cry.

Congrats and THANK YOU, Cassini team!

Jeff

Posted by: belleraphon1 Nov 22 2009, 02:52 AM

All... more Enceladus and the Rhea images are now availale...

Enceladus
http://saturn.jpl.nasa.gov/multimedia/images/raw/casJPGFullS55/N00146863.jpg

Rhea
http://saturn.jpl.nasa.gov/multimedia/images/raw/casJPGFullS55/W00061511.jpg

I have to step away from the pc for awhile.... someone may want toopen a Rhea thread.

Craig

Posted by: Loiserl Nov 22 2009, 04:01 AM

Here's a link to the website of mine where I have posted a short, 3-frame animation of Cassini's aproach to the sourthern pole of Enceladus.

Link: http://www.espaciosur.com.ar/2009/11/cassini-imagenes-del-acercamiento.html

Posted by: Astro0 Nov 22 2009, 04:41 AM

4-frame surface closeup.

Posted by: nprev Nov 22 2009, 04:42 AM

This is literally lunacy. I keep staring at these Enceladus images & they just...won't...stop...being...overwhelming. Can scarcely believe what we're seeing, really.

Astro0, really like your artistic composition; it's frame-worthy!

EDIT: And as I wrote that, you posted that terrific mosaic! (BTW, dunno how the hell we're gonna land something there someday, to say nothing of comm; talk about multipath potential!)

Posted by: Shaka Nov 22 2009, 06:06 AM

Was I born too early, or too late?
I feel what it was like to skip across the surface of the Moon.
I'll never know what it's like to lean over the lip of a geyser on Enceladus.

Astro0 understands, but his vision graces UMSF, when it should cover the front page of The Times and all the rest.

Posted by: Stu Nov 22 2009, 08:01 AM

You're right, it is. I was, as usual, "just messing about". I leave it to others here to be 1000% accurate.

Posted by: Stu Nov 22 2009, 08:20 AM

Astro0 - those two latest image creatiosn of yours are shockingly beautiful. Thanks for sharing them with all of us here.

Don't know about anyone else, but this encounter with Enceladus has made me feel an almost childlike sense of wonder again. I thought I'd have to wait maybe another 20 years to actually see the plumes coming out of Enceladus, on images taken by a post-Cassini orbiter, yet there they are, and I've been able to mess about with them and not just gawp at them.

This is nuts, absolutely nuts. On exceptionally still and clear evenings here in Cumbria I've seen Enceladus through my humble 4.5" scope. It looked just like a pinprick of light close to Saturn, a hole in the black velvet of space made by the point of a needle... now I see it, on these very pages, thanks to the Cassini team and all my friends and fellow explorers here, as a world, a real world, criss-crossed with meandering canyons of ice, covered with fields of snow and slashed by deep, axe-wound gorges out of which gush geysers...

One day people will walk up and down those canyons, running their gloved hands along their sides, maybe stopping to carve out intricate designs in the ice, leaving their mark as humans are always moved to do. One day spacesuited children will bound across those snowfields, boots crump-crumping as they land, laughing and giggling in the low gravity. One day explorers will stand on the edge of Baghdad Sulci and stare wide-mouthed at the beauty of the scene, leaning back to stare up at the geyser erupting out of the ground before them. Seen through the geyser's veil, the Sun will be surrounded by glorious haloes of rainbow-hued light, and the stars above them will shimmer and dance...

And standing there, beside that geyser, they'll wonder how it felt like to be us, here, in 2009, to be the first people to see the beauty of their homeworld, on grainy images taken by a tiny, Mayfly-fragile spaceprobe sent out across the gulf of space by a generation that Wanted To Know.

Amazing.

Posted by: jasedm Nov 22 2009, 09:18 AM

Certainly a candidate for most stunning spacecraft encounter this year - breathtaking. Imagine what a radiation-hardened orbiter could achieve at Io - (obviously it could come nowhere near as close to Io's plumes though....)

Posted by: dilo Nov 22 2009, 11:32 AM

I was plaiyng with Stu mosaic, in order to enhance weaker plumes parts...

Hope you enjoy this "psychedelic" result!

Posted by: ugordan Nov 22 2009, 01:27 PM

Ooh, shiny!

IR3/GRN/UV3 filters, Saturn http://i108.photobucket.com/albums/n15/ugordan/saturn_ir3grnuv3.jpg in this filter combo which I think is kind of neat. Otherwise no color apart from hints of blue at the tiger stripes.

Posted by: ngunn Nov 22 2009, 02:30 PM

Amidst the excitement I almost missed this excellent article:
http://saturn.jpl.nasa.gov/news/cassiniinsider/insider20091119/

Thanks for all the wonderful image work folks (now continuing on Rhea also).

Posted by: scalbers Nov 22 2009, 02:33 PM

Astro0 quote: Here's the artists view. <<<There's your clue right there!

Wonderful - as I wondered how this might look in color. Is this from multi-color imagery or somehow colorized? I did see some color filter images are available.

One "analysis" type of thing that can be done is to apply a mapping transformation to the image(s) so we can see where the source regions are (by comparing to the map of fully lit images). I'll see if I can give this a shot.

Posted by: JTN Nov 22 2009, 02:57 PM

The http://saturn.jpl.nasa.gov/news/cassiniinsider/insider20091119/ that ngunn linked to seems to have answered that:

Posted by: tfisher Nov 22 2009, 03:44 PM

I wonder if we might spot sun dogs in the backlight plume images, if we look in the right spot? Water ice crystals give a refraction halo at about 22 degrees. (see e.g. http://hyperphysics.phy-astr.gsu.edu/HBASE/atmos/halo22.html). Can anyone good with orbit/camera geometry identify if this angle is covered in the Enceladus imagery?

Posted by: eoincampbell Nov 22 2009, 04:25 PM

From these images, would the Cassini team (or UMSF team!) be able to discern if the plume activity has intensified since E6?
Looks... so... alive...

Posted by: Sunspot Nov 22 2009, 04:33 PM

I think i'm Stereo blind

Been staring at the stereo pairs posted here and on the Planetary Society website to no avail.

Posted by: ugordan Nov 22 2009, 04:48 PM

Tfisher, keep in mind the FOVs of Cassini cameras are 3.5 and 0.35 degrees so without knowing the exact geometry it would be rather difficult to determine whether a halo ring (I'm thinking no sundogs as the particles here are in freefall) crossed a certain image. Obviously, such a halo ring would be pretty diffuse and wide even in wide-angle images and with localized plume emissions I'm not certain how obvious it would be.

One last image from me, this time (yet another!) soft colorization of what has to be my favorite shot of the encounter, N00146847. Just enough to not make it look grayscale, but not to overdo it for realism's sake.

The foggy appearance of the scene with the moon's limb cutting sharp shadows across makes it somehow look less alien and more familiar, down to earth.

Posted by: scalbers Nov 22 2009, 05:31 PM

Here's a mapped version of a plume image at 2K map size. The next step might be converting to polar and blinking on top of the hi-res map. I'll also try this with larger map sizes.



Steve

Posted by: Poolio Nov 22 2009, 05:43 PM

I'm late to the party and I have nothing to contribute, but I just can't let the opportunity pass without registering my awe at what I am seeing here. I am stunned. My sincerest thanks to the Cassini team and to all of you for producing these amazing aritifacts.

Posted by: ngunn Nov 22 2009, 06:47 PM

Mine too, and that's a great version of it Gordan. I like the way the curved dark limb and the straight shadow edge on the right are clearly distinguishable. The whole thing gives the deceptive impression of being a wide-angle panorama rather than a telephoto shot. It seems to pull the observer right down there into the airy space where the plumes rise like auroras.

Posted by: scalbers Nov 22 2009, 06:55 PM

Here's the mapping comparison I mentioned earlier to help locate the plumes on the dark side of the terminator (click to animate):

It's interesting that the forked nature of the left plume appears to have a correspondence with the forked end of Alexandria Sulcus. The more intense spot is where the fork is. The other plume being traced out on the dark side is Cairo Sulcus. Here the really intense spot at the terminator matches a kink in Cairo Sulcus. The original image I used is N146851 so we could in principle proceed to annotate the image with the associated sulci.

Steve

Posted by: ugordan Nov 22 2009, 07:00 PM

First time I saw it, I thought the shadow is the limb and thought no way, look at that relief!

Steve, is it me or is the plume image noticeably shifted w/ respect to the basemap?

Posted by: Juramike Nov 22 2009, 07:02 PM

Nice!

Posted by: scalbers Nov 22 2009, 07:15 PM

Gordan - yes I can see a shift in the terrain features too. This is kind of a first attempt at matching the geometry while reprojecting the image. As a quick fix they could be shifted around to fit better - feel free to give that a try. Meanwhile I can see about making some adjustments in the reprojection geometry.

There would be an additional shift in the plumes themselves since they of course are above the surface. One can try and extrapolate them down to the surface if you follow the direction of the eruption.

Steve

Posted by: dilo Nov 22 2009, 07:34 PM

Another mosaic joining frames N00146711 and 710 (with deinterlace technique):

Posted by: scalbers Nov 22 2009, 09:07 PM

Update to post #130 plume comparison map with a somewhat better match (click on animation):

Steve

Posted by: elakdawalla Nov 22 2009, 09:18 PM

This was as wide a shot on the plumes as I could come up with. Mosaic of N00146851 and N00146855. I cannot get over how cool it is that we can see those plumes issuing from the darkness. Even after the sun has set on the south pole for the winter, for quite a while we'll be able to see the tiger stripes outlined by the sunlit plumes wherever they reach high enough elevation to see the Sun.

There appears to be a ring feature on the terminator, made of concentric circles of low ridges. I think. I wonder if this is an impact feature, or just a trick alignment of ridges and shadows? Does it line up with anything on the maps? I see something roundish in Steve's blink gif. Someone on the imaging team, I forget who, was doing some tectonic reconstruction on the Enceladan south pole -- I wonder what they thought of that feature? It's certainly dramatic in the oblique views.

--Emily

Posted by: scalbers Nov 22 2009, 09:30 PM

Looks as Emily and I are looking at the same roundish feature - have yet to see a name for it, being between Alexandria and Cairo in http://laps.noaa.gov/albers/sos/saturn/enceladus/Enceladus_map.jpg. In her wide shot from left to right we can trace Alexandria, Cairo, Baghdad, and a bit of Damascus Sulci, though the latter two are outside of my comparison map (post #135).

Steve

Posted by: nprev Nov 22 2009, 09:46 PM

Was wondering if I was the only one wondering about that 'ring feature'. Amazing how pronounced it is at a low illumination angle; it's hard to even recognize from the overhead images.

Sure looks like a highly modified impact crater to me, though agree that it's hard to be sure given the chaotic nature of this terrain. If it is in fact a crater, could provide some interesting insight re the age of the surface.

Posted by: antipode Nov 22 2009, 09:54 PM

Ring feature = diapir?

This thing needs a name! Are there more of them?

As boggled as the rest of you by these images. They should be on front pages everywhere, but of course they wont be.

P

Posted by: ugordan Nov 22 2009, 09:56 PM

Approaching the plumes:
http://i108.photobucket.com/albums/n15/ugordan/flythru.gif

Posted by: volcanopele Nov 22 2009, 09:56 PM

There have been some arguments made that the feature is a very heavily modified impact crater, a ghost crater if you will. I'm not quite sure I subscribe to that, but I guess something had to happen to the craters after the region got chewed up and spat out.

Another reasonable argument, antipode.

Posted by: ngunn Nov 22 2009, 10:17 PM

I too was wondering about the apparent ring feature, but after locating it on the map concluded that it was probably nothing in particular, perhaps a patch of surface that has rotated somewhat due to activity on surrounding fractures. Of course that's not inconsistent with an impact having set up the fracture pattern in the first place.

Emily the first image in your post provides exactly what I've been waiting for since first seeing Stu's version - thanks! That's the one for my wall.

Posted by: Gladstoner Nov 22 2009, 10:21 PM

.

Posted by: nprev Nov 22 2009, 10:42 PM

Ooo...GREAT animation, Gordan!

Cassini did in fact blast right through the biggest plume, right? Looks like she went through a little curtain of lesser emissions immediately prior to that.

Posted by: ugordan Nov 22 2009, 10:46 PM

I don't know which part of the plume it went through, but tracking a certain feature like above can be deceptive. Cassini might have been going more sideways than towards that particular "hotspot".

Posted by: ngunn Nov 22 2009, 11:16 PM

Would anybody like to guess which sulci the main plumes on the horizon belong to?

Posted by: ngunn Nov 22 2009, 11:23 PM

My guess is that smooth means old around here, so one side of that fracture is older than the other. What is the sharpest feature we can find in these images and how recent might it be? This must be a question the Cassini scientists are addressing.

Posted by: scalbers Nov 22 2009, 11:34 PM

My guess for the brightest three spots on the limb in Emily's wide angle image is (left to right) Cairo, Baghdad, Damascus.

Approach was from 195 west longitude, passing closest approach at 80S 120W. So it looks to have flown mostly along the Cairo plume passing most directly over it just on the sunward side of the terminator.

To help piece the puzzle together I have a coordinate grid on the image used for the map comparison. Longitude lines are every 20 degrees with the green longitude line at 180. Latitude lines are every 15 degrees. It may have passed just left of the brightest plume (slight slant of path over Cairo Sulcus) on the horizon in this image. Closest approach would be on the visible side midway between the terminator and the limb/horizon.



Hopefully I've got this straightened out. It might be interesting to overlay the ground track on the above image.

Posted by: Vultur Nov 23 2009, 12:58 PM

These pictures are absolutely, completely incredible! What an amazing moon...

Posted by: ustrax Nov 23 2009, 03:16 PM

One leaves for the weekend and in the meanwhile we fly straight through the freaking plumes of Enceladus?! Someone please slap me in the face, I have a facial paralysis...

Posted by: paxdan Nov 23 2009, 08:30 PM

http://news.bbc.co.uk/1/hi/sci/tech/8374194.stm

Posted by: Spin0 Nov 23 2009, 10:56 PM

Hi!

I have a video on the works, and while working on it I noticed something quite amazing (well, to me anyway - could be old news to you folks here).
Those streaks in the plume images do not look like random cosmic rays, as they go on image by image. I think they are particles. Visible ice particles from the plumes. Beautiful!

For example compare these two beauties:
http://saturn.jpl.nasa.gov/photos/raw/rawimagedetails/index.cfm?imageID=207371
http://saturn.jpl.nasa.gov/photos/raw/rawimagedetails/index.cfm?imageID=207372

Ok, news to me, maybe old news to you. Still amazing to see them passing by Cassini.

(still removing stripes, five more images to go, going carpal... sleep now and video ready in 10 hours. )

Posted by: ugordan Nov 23 2009, 10:59 PM

Those streaks are stars in the background, Spin0. Other pixels which don't "move" between frames are hot pixels with abnormally high dark current rates - due to cosmic ray damage. The rest is your typical cosmic ray hit stuff.

Posted by: Spin0 Nov 23 2009, 11:11 PM

Sorry for the false alarm then, and thank you for the quick reply. I really have to get some sleep now.

Yet, have a look at this:
http://saturn.jpl.nasa.gov/photos/raw/rawimagedetails/index.cfm?imageID=207373
What are we seeing here?

Posted by: ugordan Nov 23 2009, 11:13 PM

I see two long star streaks and the rest are hot pixels and cosmic ray hits. The latter can also take on appearance of streaks if the hit is at an oblique angle. Not very common, but it does happen, especially during long exposures like that one. Typically, such artifacts are very sharp, i.e. one pixel can be completely saturated while the adjacent one completely dark, but with real objects, camera's point spread function tends to blur point sources slightly. Hard to notice in compressed jpegs, but more noticeable in calibrated images. Note for example how the star streaks have a certain softness to them.

Posted by: HughFromAlice Nov 24 2009, 04:48 AM

I've been so busy I somehow forgot to keep up with all this. I dreamed of images something like these when I was a kid reading science fiction - and now they are for real! And the image makers of UMSF have done a nice job too!!!

Thank god for skeet shooters. As for whole words, these came into my mind....

The cloud-capp'd towers, the gorgeous palaces,
The solemn temples, the great globe itself,
Yea, all which it inherit, shall dissolve,
And, like this insubstantial pageant faded,
Leave not a rack behind.

We are such stuff as dreams are made on;
and our little life is rounded with a sleep.


Prospero in the Tempest (PS Vaughan Williams did a wonderful job putting this to music).

Posted by: Stu Nov 24 2009, 07:48 AM

Well done Emily, on having your Enceladus image used as today's APOD!

Posted by: HughFromAlice Nov 24 2009, 12:17 PM

Yes, well done.

Posted by: scalbers Nov 24 2009, 06:28 PM

For some reason this makes me think of some type of interplanetary ski resort with all the snow guns going at full blast.

In terms of the ground track it may be less relevant for this flyby. Being at a relatively large distance (1600km) the individual plume sources may have merged by the time they reach Cassini's altitude. On the other hand plotting the ground track of the Nov 2nd 102.7km flyby on the Nov 21 images might be of some interest if we can assume the plumes are constant enough on that time scale.

Steve

Posted by: rlorenz Nov 24 2009, 07:23 PM

Spectacular images indeed. Well done ISS team!

The Enceladus/snow cannon analogy has been brought up before. I was doing the night-ski
thing at Whitetail (PA) earlier this year and they had the snow guns going. I was moved to
send the attached text message to a friend who was meteorite-hunting in Antarctica at the time

snow guns blast the night
Curtains of ice dust rain down
like Enceladus

Posted by: sgendreau Nov 24 2009, 08:21 PM

Haven't seen this image here yet, and it's wonderful:


http://ciclops.org//view_media.php?id=29884

from

http://ciclops.org/view_event/120

Posted by: ngunn Nov 24 2009, 09:14 PM

Post 102?

But more recently we have this one, in which the plumes are visible against the night side as in the spectacular narrow angle shots:
http://saturn.jpl.nasa.gov/multimedia/images/raw/casJPGFullS55/W00061616.jpg

Posted by: sgendreau Nov 24 2009, 11:45 PM

Oops. (smacks head) Sorry, y'all.

Posted by: Ron Hobbs Nov 26 2009, 01:20 AM

That famous oblique view of the lunar crater Copernicus was dubbed by some as the "Picture of the Century." When I show it in my presentations, I tell my audience that they might well see the picture of this century before it is all over. But I really didn't believe it; while we have seen some really cool pictures, the century is awfully young.

But http://apod.nasa.gov/apod/ap091124.html has got to be a candidate for THE Picture of the 21st Century. (Congratulations Emily.)

Looking at the pictures from this encounter, I remembered an exclamation uttered during one of the Voyager encounters of the Saturn system almost 30 years ago. I clipped the following picture and quote, I think from the San Francisco Chronicle:

I attribute this quote to Ed Stone, though I am unable to document it with anything other than my memory. Any way, I share it, in part to celebrate that we are still looking for the unimaginable. It is a kind of crude attempt attempt to do what Asto0 and others do here regularly. (That is Mimas, in case anyone can't make it out.) We certainly have come a long way!

Oh yeah, and we are coming up on the 30th anniversary of Saturnian exploration.

Thanks again to all involved for such incredible views.

Ron

Posted by: stevesliva Nov 26 2009, 02:05 AM

Incidentally, the lighting required for such a view will likely not be seen by any other camera for at least 30 years. I am betting that nothing will be there in 15. (And is the lighting equivalent then, at the next solstice? Or is it 30 anyways?)

Posted by: scalbers Nov 26 2009, 03:51 PM

The same solar declination and lighting would be near the next equinox in around 15 years. However even when the sun goes somewhat more to the north it seems there would be opportunities to see as much or even more of the plumes just over the dark side of the terminator from a well positioned spacecraft (including Cassini).

Posted by: john_s Nov 26 2009, 04:20 PM

Note that there's another remote-sensing Enceladus encounter coming up on Rev. 136 (August 13th 2010), with a high phase angle approach, in which we will still have grazing-incidence sunlight on some of the plume sources, and probably we'll get equally spectacular views. So the current season ain't over yet...

John

Posted by: scalbers Nov 26 2009, 07:23 PM

Here's a rough blinking overlay of Emily's mosaic on top of a Celestia view to help get our bearings (click to animate). There are some polar pinch effects with Celestia so maybe another rendering engine would help.

Steve

Posted by: jasedm Nov 26 2009, 07:59 PM

That date would take us into the XXM.... Do you know something we don't John....

Posted by: scalbers Nov 26 2009, 08:25 PM

And here by the way is an annotated version (click to animate):

Almost think I can see part of Damascus Sulcus illuminated on the dark side.

Steve

Posted by: john_s Nov 26 2009, 08:28 PM

Nope, no inside information here, but the planning is going ahead on the assumption that we will be funded at least for the first part of the XXM, and realistically it's unlikely that the plug would be pulled on such short notice. No guarantees, of course...

John

Posted by: Shaka Nov 27 2009, 12:12 AM

Tres cool effect, kimosabe! How about blending the two views so we actually see the plumes emerging from the sulci?
TIA

Posted by: Stu Nov 27 2009, 03:13 PM

Some words inspired by the plume images...

http://twitpic.com/r63j0/full

Posted by: scalbers Nov 27 2009, 04:31 PM

Interesting idea Shaka, here is what it looks like with a simple blend:



Thanks to Stu for the poetry.

Steve

Posted by: ugordan Nov 27 2009, 04:34 PM

That's neat stuff, Steve!

Posted by: scalbers Nov 27 2009, 06:44 PM

I wonder if this (or another) close encounter will have some Saturn-shine to help illuminate the dark side?

Posted by: claurel Nov 27 2009, 06:55 PM

One thing you can do to mitigate these polar pinch effects is to force anisotropic filtering on via the control panel for your graphics card. I think this is only an option for Windows users. Also, the polar pinch problem has been addressed in the development version of Celestia--send me a PM and I can tell you how to get a recent build.

--Chris

Posted by: john_s Nov 27 2009, 10:04 PM

The Rev 136 encounter approach longitude is ~210, on the anti-Saturn side (similar to the Rev. 121 geometry, in fact), so there won't be much Saturn-shine illumination on approach, though Saturn shine will of course reach to the south pole, which sunlight won't do. The next encounter with a good remote-sensing view of the south pole won't be till December 19th 2015 (assuming the mission goes that long, of course), and we'll probably want to use Saturn-shine to look for changes at the south pole, as the sun will be a long way from the pole by then.

John

Posted by: Shaka Nov 27 2009, 10:11 PM

Oh, man! This place would turn anyone to poetry!
I'm now considering having myself frozen for a century or so, to be thawed out when I can take over the Rent-a-hang glider concession for Baghdad Sulcus. I'll lead guided tours to the south pole, with frequent swoops down to the vents!

Posted by: martin peters Nov 28 2009, 02:15 AM

Take a look at some small portions of Rev 121 flyby images #6 and #7 on the Cyclops website. These cropped portions are from near the bottom of both images. Image #7 is slightly less clear than #6, and there appears to be foreshortening of the features shown in #7 because the camera was looking at more of an angle rather than straight down. However, there is an apparent difference in the brightness of the linear feature just below the two little dark spots that I do not think can be attributed to any change in sunlight on the landscape in the few minutes between the images. Any ideas about what might have changed?

Clip from Rev 121 raw #6

Clip from Rev 121 raw #7

Posted by: ngunn Nov 28 2009, 09:38 AM

I think you said it right there: that must be an away-facing slope. If so it should be possible to infer the gradient from these images. I tried viewing them as a cross-eye pair but couldn't make it work. Perhaps it would be worth scaling and aligning them properly with 3D viewing in mind. Maybe some of the slopes would pop into view.

Posted by: Exploitcorporations Nov 30 2009, 04:58 AM

More late additions to the party, but nothing can top those plume images! This is an attempt at the big mosiac of the southern leading hemisphere. The changes in spacecraft position make this one dirty, but it does show the extent and detail...very much looking forward to VP's clean orthographic version. Three small gaps have been plugged with lower-resolution frames from late in the encounter.

Posted by: Exploitcorporations Nov 30 2009, 05:14 AM

These are the seven highest-resolution frames post-encounter, cropped from the big mosaic. The spectacular vertical shot of the "canyons" is in the foreground at lower center right, covering part of a nearly obliterated fractured crater in the transition zone. The reprojection of the images to the perspective of the big mosaic adds to the sense of landscape ,so I've flipped it.

Posted by: nprev Nov 30 2009, 05:18 AM

...fantastic. Always good to see you, EC!

Posted by: Exploitcorporations Nov 30 2009, 05:50 AM

Likewise, nprev! We've had sporadic computer access and internets for weeks, and it's always good to be back.

Those eye-shaped "islands" of terrain appear all over the place...the pair to the southwest in the big mosaic have fascinating trapped chunks of cratered terrain. Emily mentioned the ring-shaped polar feature in post 136, and I wonder if they are different stages of the same process, or merely a case of pattern recognition.

Posted by: belleraphon1 Dec 2 2009, 02:30 AM

Gorgeous mosaics EC!

Craig

Posted by: nprev Dec 2 2009, 03:15 AM

Indeed they are!

Those 'chunks' are very reminiscent of similar features on Europa, albeit probably much older geologically. I've always assumed that they are thicker pieces of ice that resisted the underlying convective process enough so that surrounding terrain deformed instead & relieved the stress.

Posted by: scalbers Dec 5 2009, 04:18 PM

Nice to see you back EC with some interesting and highly detailed mosaics of the encounter. Here is an updated map including both medium and a majority of high resolution coverage from this flyby.

Posted at 8K resolution online at http://laps.noaa.gov/albers/sos/sos.html#ENCELADUS.

Steve

Posted by: volcanopele Feb 23 2010, 08:13 PM

Images and mosaics from the Nov. 21 encounter with Enceladus have now been released:

http://ciclops.org/view_event/129/Forest_of_Jets

Press release: http://ciclops.org/view.php?id=6226

Posted by: Exploitcorporations Feb 24 2010, 06:32 AM

Thanks so much, VP...been waiting for those impatiently. Very cool.

Posted by: scalbers Mar 7 2010, 06:07 PM

The CIRS overlay is interesting showing >180K temperatures measured. How much higher might they be at sub-pixel resolution (and of course underground)?

Posted by: Bill Mar 25 2010, 09:06 PM

Damascus on Enceladus ? No, Eyjafallajoekull in Iceland.
Just change the color in white and blue and you can imagine flying over enceladus...

Enceladus on earth

How about a link? ADMIN

The link is :
http://www.youtube.com/watch?v=VwdOH9GayVw

Sorry.

Posted by: JohnVV Mar 26 2010, 06:07 AM

that "blue " color is not there in visible light
It is in the UV part of the spectrum .However some of us have added the "blue" to our maps
mine and Steve Albers ( from the above posting)
[attachment=21200:Screenshot.jpg]
[attachment=21201:Screenshot_1.jpg]

this reminds me
I need to update this map

Posted by: scalbers Mar 26 2010, 01:25 PM

John - I think some of the blue is visible in RGB imagery, hence a partially desaturated presentation of IR/G/UV imagery might be fairly realistic. I've attempted to do this in my map. We've discussed how ice can appear blue elsewhere in this forum:

http://www.unmannedspaceflight.com/index.php?showtopic=5371&st=240&p=123832&#entry123832

Posted by: ugordan Mar 26 2010, 02:00 PM

This is not correct AFAIK. The spectrum of the blue ice appears fairly flat across the visible and near UV wavelengths. The "blue" appearance in Cassini imagery actually stems from the use of the farther IR filter (IR3) where the crystalline ice is dark. This gives the effect of the ice being blue-green, compared to the rest of the surface, it's actually not intrinsically brighter in UV than the amorphous ice in its surroundings. It's pretty obvious when you flip through individual, calibrated IR3/GRN/UV3 images.

The same blue-green hue is very very subtle in natural color imagery, I suppose if you squinted real hard with the naked eye, you'd be able to see the tiger stripes have a bluish tint to them.

Posted by: scalbers Mar 26 2010, 02:16 PM

Since I can see some color in the low-res RGB imagery I think it's possible that some deeper blue colors in localized sub-pixel areas would look more impressive to the naked eye at close range. Deep blue colors in earthly ice can be localized in this fashion.

Posted by: ugordan Mar 26 2010, 02:25 PM

Keep in mind most of the imagery is presented in a non-gamma correct fashion which boosts any contrast and color saturation over what is otherwise present. This would be offset somewhat by the eye's ability to pick out even slight differences in hue. It would probably be noticeable, but wouldn't readily stand out.

Posted by: scalbers Mar 26 2010, 04:10 PM

Interesting the IR absorption of ice decreases at lower temperatures. Could this mean that outer solar system ice is less blue than on Earth?

http://www.lowell.edu/~grundy/H2Oice.html

Posted by: JohnVV Mar 26 2010, 06:37 PM

my oops .

Posted by: machi Nov 12 2010, 09:52 PM

Morph animation of Enceladus from three frames.
Timewarp 25×.

Posted by: machi Nov 13 2010, 11:31 PM

Second animation from same encounter.
Timewarp 6×.

Posted by: Hungry4info Nov 13 2010, 11:54 PM

Wow nice!!

Posted by: machi Nov 16 2010, 03:29 AM

Third animation from 21.11.2009 encounter. It's made from four images. Timewarp ~25×.
http://planets.wz.cz/saturn/satorig/enc_cas_dam_004.avi

And second animation in better quality:
http://planets.wz.cz/saturn/satorig/enc_cas_dam_005.avi

Posted by: lyford Nov 16 2010, 04:37 AM

Gorgeous!

Posted by: eoincampbell Nov 16 2010, 05:55 AM

My new mac mini is really loving these animations.
This perspective truly inspires awe... thank you very much!