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Posted by: Juramike May 9 2010, 06:47 PM

Nice shot of Rhea against Saturn taken on May 8 2010:

This is the exact same geometry as Planetary Photojournal Image http://photojournal.jpl.nasa.gov/catalog/PIA10494.

Posted by: dilo May 10 2010, 03:05 PM

Great catch, Juramike!
Is it an RGB composition?

Posted by: Juramike May 10 2010, 05:12 PM

It was indeed. I was guessing it was a Cassini "Mother's Day" special, with Saturn, Queen of the Solar System, with her daughter Rhea.

Posted by: cbcnasa May 11 2010, 04:22 PM

Nice work

Posted by: S_Walker May 13 2010, 03:02 PM

Rhea behind the rings, May 11, 2010... I think the other satellite is in front of them.

Posted by: Juramike May 14 2010, 12:04 AM

Three-frame animation of Iapetus from May 7th, 9th, and May 12th observations (May 12th is RGB, May 9th was colorized to match):

Posted by: Juramike May 18 2010, 09:47 PM

False color zoom of Enceladus RGB = IR3, GRN, UV3. Lotsa wrinkly terrain, a couple narrow deepcrevasses superposed, and a splat crater with fresh white stuff.
(Note crater on left without the splat.)

Posted by: elakdawalla May 18 2010, 09:57 PM

What the...?
http://saturn.jpl.nasa.gov/photos/raw/rawimagedetails/index.cfm?imageID=216821

EDIT: OK, now I've figured out why it looks so weird. Low phase angle plus relatively fresh uncratered terrain. We're seeing albedo differences as much as light/shadow differences. Still, it's very weird looking!

Posted by: Bill Harris May 18 2010, 10:09 PM

Yes, unusual. Islands of old terrane in a active spreading zone?

It is "RGB"...


The (temporary) jawdropper in this batch was the saturnshine/crescent Dione (N00153920).


--Bill

Posted by: elakdawalla May 18 2010, 10:28 PM

Does this 3D work for people? I can't tell if I'm really seeing 3D or if I am willing my brain to see it

Posted by: Bjorn Jonsson May 18 2010, 11:27 PM

And the automatic contrast stretch is probably messing things up as there's probably no completely black space visible in this image - some shadows though.

Posted by: volcanopele May 19 2010, 12:14 AM

Interesting that no one has mentioned this one...

http://saturn.jpl.nasa.gov/multimedia/images/raw/casJPGFullS60/N00154034.jpg

Posted by: nprev May 19 2010, 12:26 AM

...Thanks for pointing it out, VP. The upper-haze ring on Titan is just amazing in this context!

Emily, I think I see 3D in your image, but it sure is subtle. Is the surface relief here perhaps a lot less than you'd expect from the albedo & illumination variances?

Posted by: stevesliva May 19 2010, 12:43 AM

I think your eyes did not discern the solid surface of Enceladus in the foreground... or did they?

Unbelievable.

Posted by: Juramike May 19 2010, 01:42 AM

Oh wow. Me so likey:

http://saturn.jpl.nasa.gov/photos/raw/rawimagedetails/index.cfm?imageID=216997

Posted by: Astro0 May 19 2010, 04:21 AM

An amazing series of image from Cassini.
What about this one
http://saturn.jpl.nasa.gov/photos/raw/rawimagedetails/index.cfm?imageID=216991

Posted by: Astro0 May 19 2010, 04:33 AM

Looking at that Titan image with the rings and Enceladus' surface in the foreground and then at the Enceladus geyser image, I noticed that the horizon on Enceladus pretty much matched up in each image.

So I guess that under the different cameras and lighting conditions, this combined image is what Cassini was heading towards.

Posted by: Stu May 19 2010, 05:41 AM

G O O D G R I E F...

Posted by: brellis May 19 2010, 06:14 AM

wow! Cassini is building us a nice library for a virtual tour of the Saturn system.

Posted by: Explorer1 May 19 2010, 07:26 AM

Words fail me yet again!

Cassini, you're gonna make us go nuts if you keep this up much longer!

Posted by: Astro0 May 19 2010, 08:10 AM

Approaching Enceladus - animation (forward/reverse)

Couldn't resist doing an artistic desktop version of the combined image.

Posted by: ynyralmaen May 19 2010, 10:46 AM

Absolutely amazing images.

Just trying to interpret the plume jet images... although my brain tends to interpret the structure as being in the background, I guess the "lines" oriented towards the 8 o'clock position must be the shadow of Enceladus falling on the jets, so they're actually foreground features, not background, I think.

When oriented with the plume pointed downwards, I guess that means that the large plume jet on the right is all beyond the local horizon and illuminated all the way down to the horizon as seen from Cassini, the middle one straddles the limb so that only part of it is in shadow, while the source of the left-hand jet is in darkness, i.e. closer to Cassini than the limb, and it only becomes visible when it emerges into sunlight. Does everyone else interpret these in the same way?

Posted by: Hungry4info May 19 2010, 11:00 AM

I agree with your interpretation, ynyralmaen.

Posted by: Juramike May 19 2010, 12:15 PM

Multiple frame mosaic of Enceladus against the rings in high-phase glory:

Posted by: fredk May 19 2010, 03:14 PM

I think I agree. One thing I'd add is that it seems like much of the bright plumes aren't in direct sun, but are illuminated by scattered light, perhaps from the sunlit parts of the plume, or perhaps from Saturn. I've indicated with the black arrow a notch in the central bright plume that aligns with the shadow heading off to the lower left. Presumably below the notch (in the image's orientation) the plume's in full sun, and above (closer to Enceladus) it's lit by scattered light:

I'm still puzzled by the appearance of the left plume, in particular why is it's upper right edge oriented the way it is?

And I think I can see the central plume in the Enceladus/Titan/rings frame, circled here:


It's extremely subtle, which I guess is what you'd expect. When the exposure is set for Titan and the rings, the plumes are extremely faint.

Posted by: ynyralmaen May 19 2010, 04:02 PM

Maybe above that notch we're just seeing the part of that jet that's in full sunlight, while the part of the jet nearer to Cassini is in darkness, so the integrated brightness is lower?



If the shadow of Enceladus is a cylinder, then if that particular jet is oriented so that its long axis (i.e. "along" the sulcus) is close to perpendicular to the axis of the shadow cylinder, I think that odd orientation can be explained. Maybe.

Posted by: ngunn May 19 2010, 04:10 PM

On your last point, I agree and I think the other two plumes are also marginally visible in that image.

I don't quite agree about some of the rest however - at least not yet! I do do not think we're seeing plume material except where it's directly lit by the sun. I think the strange shape of the left plume is due to it's lowest part (nearest to Enceladus) being in shadow and invisible. The edge of the plume nearest the centre of the image would be the nearest part to the viewer with more of its lower bit unilluminated. As it snakes off from there towards the horizon less and less of it is in shade and so it appears to descend to meet the surface. (All of this is MUCH easier to picture with the image the other way up!) We saw the same thing on the earlier flyby with plumes apparently detached from the surface of Enceladus where their bottoms were in shade. This is the same, except the sun is now just below the horizon rather than just above, so the viewer is now 'underneath' the shadow edge. ('Down' means towards the ground here.)

Regarding the notch - I think this is due to contrast at the edge of the moon's shadow on more distant E-ring material that we're seeing through and beyond the plumes.

Posted by: dilo May 19 2010, 09:00 PM

Image composition from Astro0 is a masterpiece!
I made similar version without Cassini, different plumes color and reoriented south pole:

Original images are N00154031 and N00154034... I think this is one of the most spectacular images ever sent by a probe.

Here below also an elaborated version of W00064072 picture (without blooming); you can barely see the plumes in the lower part:

Posted by: JohnVV May 19 2010, 09:24 PM

a bit late in the thread but not in time ( Yesterday, 07:27 PM
)

i find that a big problem . and like to do 32 bit tiff's and not 8 bit png's

Posted by: Shaka May 19 2010, 09:38 PM

Thanks, folks.
Roll over and sigh, Stanley Kubrick.

Posted by: nprev May 20 2010, 01:46 AM

Astro0, that's one of the most awe-inspiring vistas ever made...really makes you feel the majesty that surrounds our little robot. Thank you.

Posted by: lyford May 20 2010, 04:53 AM

And I couldn't resist downloading it! Thanks!

Posted by: Astro0 May 20 2010, 12:23 PM

Cassini press http://saturn.jpl.nasa.gov/news/cassinifeatures/feature20100519/ on the Enceladus-Rings-Titan image.

...Enceladus put its craggy face forward, exhibiting some of the fractures and cratering that have made the Saturnian moon a favorite of both planetary scientists and outer-planet mission groupies...

Groupies? Do you think that they're talking about us?!

Posted by: Stu May 20 2010, 01:36 PM

Groupies? If we're groupies then where's the free booze and raucous rock n roll party?!?!?!

Posted by: Phil Stooke May 20 2010, 01:40 PM

Back at my place, Stu!

Phil

Posted by: Stu May 20 2010, 02:13 PM

Now we're talking!

Posted by: Juramike May 20 2010, 05:08 PM

Stage dive?

Posted by: mgrodzki May 20 2010, 11:07 PM

This message was originally in a different thread - moderator

How is it that “I” am the one to start the thread on this flyby?

What am I seeing here?! I mean… the geysers, yes… what the hell are those straight line edges? artifacts?

Posted by: centsworth_II May 21 2010, 02:40 AM

This message was originally in a different thread - moderator

There is a long discussion of that image and others in the http://www.unmannedspaceflight.com/index.php?s=&showtopic=335&view=findpost&p=159836 thread. [now in this thread - moderator]

Also, see http://planetary.org/blog/article/00002497/

Posted by: eoincampbell May 21 2010, 04:24 AM

My congrats to the planners and executors of this astounding series of images.. and of course the groupies who have shared...

Posted by: Stu May 25 2010, 05:43 PM

New astropoem inspired by the stunning image we all love...

http://astropoetry.wordpress.com/2010/05/25/titan-rising

Posted by: ngunn May 26 2010, 08:58 PM

Stu, I too love that image - in fact I think it's the most spectacular single ISS frame Cassini has obtained - and I enjoyed your poem. However a couple of lines surprised me, the ones about there being no sign of the plumes. On my monitor I can see the brightest parts of two of the plumes, centre and left, in that image. They're faint, but they're there, and for me that is the icing on the cake as far as this image is concerned. It's a bit like the Earth and Moon in that iconic backlit Saturn mosaic or Phoenix under its parachute from HiRise - so nearly invisible that you really have to look carefully and yet there they are, almost against the odds. Wonderful.

Posted by: Stu May 26 2010, 09:21 PM

Thanks Nigel, glad you liked it. I must admit I used a bit of artistic licence there, just to make it scan better; bit of a mouthful saying "Of the plumes... well, they're very faint but they're there if you look closely enough..."

Posted by: ngunn Jun 3 2010, 09:16 PM

As soon as I saw that classic image I knew what I wanted, but didn't have the skill to do it. Basically just enough colour on Titan to dismiss the thought "Pity it's only in black and white". So I went and asked for help, with the brief: preserve the original tone values, subtly colourise Titan and leave the rest unaltered. On seeing the first attempt I've suggested a couple of minor tweaks but even if it gets no better than this I'll be well pleased. Credit to Daniel Weir.

Posted by: JohnVV Jun 3 2010, 09:33 PM

like this
[attachment=21834:Titan.png]

Posted by: ngunn Jun 3 2010, 09:42 PM

Well no, actually, that's pretty unlike the version in post 449

Posted by: ngunn Jun 3 2010, 10:32 PM

Ugordan - you're there! I thought you might have a go at colourising that image. What do you think of Daniel Weir's version?

Posted by: ugordan Jun 3 2010, 10:51 PM

Well, I was kind of out of the country when that image hit so wasn't able to play around with it

I'm a proponent of not oversaturating these images, but I'd increase saturation in that particular image. Not by much, just so the different colors of the blue haze and main orange haze layer stand out better. Also maybe making the empty space really black (removing the intentional detector bias) and adding a touch of brown to the rings. The F ring and any Enceladus plumes I'd leave white.

Posted by: ngunn Jun 4 2010, 05:54 AM

Go on, have a go! Things don't have to be done while an image is headline news - we're not dealing in ephemera here. The tweaks I've suggested to Daniel are in the direction of your proposals but less ambitious. Watch here for version 2 from him.

Posted by: Bjorn Jonsson Jun 5 2010, 11:46 PM

These posts were originally in the http://www.unmannedspaceflight.com/index.php?showtopic=335 but that thread is becoming too big and has evolved to encompass almost all Cassini-related imaging topics. It has therefore been split.

Posted by: ugordan Jun 12 2010, 06:23 PM

Late to the party, but still... my version:

Posted by: ngunn Jun 12 2010, 07:15 PM

It's never too late to have one's prayers answered That is as magnificent as I knew it would be. I hope Emily picks it up, and in fact I think it deserves an APOD slot. I'll be off to a print shop at the next opportunity to order a top quality framed enlargement for my wall.

Posted by: ugordan Jun 12 2010, 07:43 PM

That's a bit too generous there, Nigel. Anyway, glad you like it.

Posted by: eoincampbell Jun 13 2010, 05:38 PM

Not at all too generous!
An image to behold indeed....

Posted by: mgrodzki Jun 24 2010, 04:00 PM

I reworked things a tad and used the Gordan color for Titan. I think the geysers would just remain white, no?

Posted by: ngunn Aug 10 2010, 09:40 AM

I got a very special birthday present this year. Thanks to NASA, especially the person on the Cassini team who planned the shot, to Gordan for his expert colouration, and of course to my daughter Elanor and wife Angela.

Posted by: ugordan Aug 10 2010, 10:26 AM

Whoa. You sure weren't kidding about framing that shot!

Posted by: Stu Aug 10 2010, 11:36 AM

Awwwwww! What a great gift!