Rev 168 - June 17th-July 10th 2012 - Titan at distance, And non -targeted Tethys Options

[jasedm]

Latest article is available
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:

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[ugordan]

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

[toddbronco2]

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/imag...4/N00191673.jpg

[nprev]

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/rawi...?imageID=264892

[toddbronco2]

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 here.

[ngunn]

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/hir...ysteriousno.jpg

[Bjorn Jonsson]

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:

[Hungry4info]

These concentric circular features are incredible.

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[Hungry4info]

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.

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[Phil Stooke]

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

Phil

[elakdawalla]

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.....

[Hungry4info]

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

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[ngunn]

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.

[Hungry4info]

Thanks.

Can you esimate the speed or period of rotation of the cloud from that?

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.

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[jasedm]

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

BTW, Tethys encounter raws are up