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Posted by: jasedm Jun 15 2012, 07:54 PM

Latest article http://www.ciclops.org/view/7229/Rev168
In summary, some distant Titan studies, more astrometric observations of smaller inner moons, and obs of the F-ring, and A-ring 'propellers'
There's a day-and-a-half stare at 'Ymir' for light-curve data, and a non-targeted Tethys encounter at ~68,000km. This should reveal Odysseus, and the northern hemisphere in some detail - closest approach images should resemble this:

Posted by: ugordan Jun 20 2012, 03:07 PM

Rough Saturn color view utilizing a wide-angle CB2 frame and a BL1 frame at 1/4 resolution:

Posted by: toddbronco2 Jun 29 2012, 03:00 AM

Wow, it looks like there's something interesting going on with this cloud on Titan. Is this a circular cloud around the pole or something?
http://saturn.jpl.nasa.gov/multimedia/images/raw/casJPGFullS74/N00191673.jpg

Posted by: nprev Jun 29 2012, 03:17 AM

Don't think that's one of the polar regions, but I could be wrong.

VERY interesting.

Also visible in a wide-angle view:

http://saturn.jpl.nasa.gov/photos/raw/rawimagedetails/index.cfm?imageID=264892

Posted by: toddbronco2 Jun 29 2012, 04:16 AM

I was surprised that there wasn't already a conversation about this going on. The scientists doing the Titan cloud monitoring will love this. No wonder they plan so many of these observations.

ADMIN EDIT: There has been some mention of it http://www.unmannedspaceflight.com/index.php?showtopic=7325&view=findpost&p=184880.

Posted by: ngunn Jun 29 2012, 09:04 AM

Titan's very own noctilucent clouds! Once again, Earth is not alone.

EDIT Here's the terrestrial version seen from space for comparison: http://cdn.physorg.com/newman/gfx/news/hires/2012/mysteriousno.jpg

Posted by: Bjorn Jonsson Jun 29 2012, 10:32 AM

This feature contains some very interesting detailed structure that I'm sure is not due to JPG artifacts. A cropped and enhanced version of the image toddbronco2 mentioned:

Posted by: Hungry4info Jun 29 2012, 12:38 PM

These concentric circular features are incredible.

Posted by: Hungry4info Jun 29 2012, 12:45 PM

Oh goodness it spins.

(animation)

Edit: It seems the programme I use to make gifs is putting some abhorrent artefacts into the animation. Hopefully someone can get a better one.

Posted by: Phil Stooke Jun 29 2012, 01:39 PM

Gifs don't like smooth gradients like these, especially if the bits/pixel are reduced.

Phil

Posted by: elakdawalla Jun 29 2012, 02:17 PM

Oh man....I have so many more things to do today.....may not be able to resist shoving it all aside to play with spinny Titan clouds.....

Posted by: Hungry4info Jul 1 2012, 10:00 PM

Taking what Phil said into consideration, I increased the contrast a bit until I was satisfied.

(animation)

Posted by: ngunn Jul 1 2012, 10:45 PM

You've done a fantastic job with this and, amazingly, no-one else has had a go, so thanks a million! Can you esimate the speed or period of rotation of the cloud from that?

I suppose it's not a total surprise that a circular weather feature is rotating, but a timescale would add a lot of information.

Next questions: Is it a cyclone or an anticyclone? The atmospheric pressure at this level is very low (-1mb) so quite a subtle energy source could be responsible. Is there radiative heating from methane condensation in the troposphere that passes right through the stratosphere before causing convection and condensation in the mesosphere? Alternatively does heating in the troposphere heft the whole stratosphere and mesosphere upward producing the same result? It comes down to this: are the (presumably ethane) mesospheric clouds cumuliform or stratiform? I don't think we have the resolution to determine that from the images alone but maybe the scientists will pull the evidence together.

Titan appears to have two weather systems one on top of the other, and going a very long way up.

Posted by: Hungry4info Jul 2 2012, 01:28 AM

Thanks.

Unfortunately not. I have no idea when exactly the images were taken.

Edit: The observability of the rotation behaviour is not new. Here it is seen on Jun 8 with Titan nearly at a full phase.

(animation)

Posted by: jasedm Jul 2 2012, 07:45 PM

Wow - that is quite something! and pretty unexpected too I would imagine - nice processing Hungry4info.

BTW, Tethys encounter raws are http://saturn.jpl.nasa.gov/photos/raw/?start=9&storedQ=2467738

Posted by: Ian R Jul 2 2012, 09:27 PM

Here's my version of the polar cap movie:

http://youtu.be/6Z3_029xlxw?hd=1

Posted by: ngunn Jul 2 2012, 11:09 PM

Good! It looks from both versions that there might be some smaller circulatory features at the edges of the main one. Can we telll for sure from the direction of rotation whether it's cyclonic or anticyclonic?

Posted by: Bjorn Jonsson Jul 3 2012, 01:23 AM

There has been a lot of interesting ring images recently, e.g. this one of the F ring: http://saturn.jpl.nasa.gov/photos/raw/rawimagedetails/index.cfm?imageID=264947

Posted by: elakdawalla Jul 3 2012, 05:36 AM

There have been a *ton* of cool images recently. I'd love to animate some of those rings images. It'll have to wait til after my vacation! And there should be a new Cassini PDS release out, right?

Posted by: Astro0 Jul 3 2012, 06:45 AM

> jasedm: BTW, Tethys encounter raws are up

Nice

Posted by: charborob Jul 3 2012, 12:49 PM

I tried animating a series of images of the rings (raw frames number N00191994 to N00192059):
 rings.mov ( 386.3K ) : 518

Posted by: Bjorn Jonsson Jul 3 2012, 01:22 PM

Looks great and makes it obvious just how variable the location of the outer edge of the B ring is.

Posted by: jasedm Jul 3 2012, 05:36 PM

AstroO - that's a beaut! - I'm going to have to train myself on photoshop!

Posted by: Ian R Jul 3 2012, 06:22 PM

Did this quickly on my laptop while watching Criminal Minds, so the color may not be very good . . .

Posted by: Ian R Jul 3 2012, 06:23 PM

A big 'wow' and 'sweet' to Astro and charborob (this forum needs a 'Like' button).

Posted by: Bjorn Jonsson Jul 3 2012, 09:56 PM

Here is an animation showing the F ring.:

 css_f_ring_20120627_p.avi ( 465.5K ) : 529


This is composed from images N00191724.jpg to N00191763.jpg (40 frames) and is encoded using the Xvid codec. The images were obtained on June 27, 2012 at a range of ~750,000 km. The frame rate is 8 frames/second so this looks a bit jerky. I therefore made an experimental version by 'tweening' the animation using the MSU frame rate conversion filter but it didn't work well for parts of the animation although other parts are better. Here is the tweened version:

 css_f_ring_20120627_p_msu.avi ( 1.48MB ) : 489

Posted by: Astro0 Jul 7 2012, 02:14 AM

Your wish is my command
http://youtu.be/T4zjYankAx0

Posted by: volcanopele Jul 10 2012, 08:41 PM

Our official image advisory on the south polar vortex is now up:

http://www.ciclops.org/view.php?id=7239

We've released an RGB color image of the stratospheric cloud taken on June 26 as well a blue filter movie.

Color image
http://www.ciclops.org/view/7235/Titans_Colorful_South_Polar_Vortex

BL1 filter movie
http://www.ciclops.org/view/7236/Titans_South_Polar_Vortex_in_Motion

There are also a pair of images taken by VIMS during the two recent flybys of this feature. While not included in this image advisory, ISS has observed this stratospheric cloud since at least March 27 (I should point out that we have seen the area for a longer period of time, albeit at the limb, but it isn't like feature just turned on over night. March 27 is just the earliest I can say that yep, the stratospheric cloud was there]
http://www.ciclops.org/view/7237/Winters_Coming
(yes someone on the VIMS is a Game of Thrones fan...clearly)

The movie covers a period of nine hours, with each frame separated by one hour (so that gives you a rotation period of about 8 hours, so some pretty fast winds at high altitude)

Posted by: volcanopele Jul 10 2012, 09:18 PM

For those curious about how big this Titan south polar vortex thing is, it's about 575x784 km (360x490 mi) in size.

Posted by: nprev Jul 10 2012, 09:38 PM

Beautiful images and a fascinating find!!! Great work, Jason!