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Unmanned Spaceflight.com _ Cassini's ongoing mission and raw images _ July 20 2007 icy moon images (rev 48)

Posted by: alan Jul 22 2007, 02:41 PM

Latest Tethys and Enceladus images are up
http://saturn.jpl.nasa.gov/multimedia/images/raw/raw-images-list.cfm?browseLatest=0&cacheQ=0&storedQ=0

Posted by: scalbers Jul 22 2007, 03:35 PM

Looks like some new details on Tethys north of Melanthius...

Posted by: MarcF Jul 22 2007, 06:34 PM

Finally some sharper views of the great Odysseus basin !

http://saturn.jpl.nasa.gov/multimedia/images/raw/casJPGFullS32/N00086709.jpg

Marc.

Posted by: Exploitcorporations Jul 23 2007, 02:16 AM

Woohoo! Very nice set this pass, and scads of new and better-defined detail north of Melanthius to concur with Steve. Quick-an' filthy summary here:

Posted by: nprev Jul 23 2007, 04:07 AM

Whoo-hoo! EC's back, layin' down the phat montages old-school...long time no perceive, don't be gone like that no more, yo!

Tethys looks more and more interesting. Confess that I don't know the nomenclature, but that rather 'lengthy' central peak in that large crater is intriguing...busted open a fault, maybe? Certainly merits futher examination.

Posted by: edstrick Jul 23 2007, 06:52 AM

In the "Pedantic Quibbles Department"...

"Finally some sharper views of the great Odysseus basin !"

Is it a "basin" if the floor is essentially everywhere convex?
(It may be a basin in relation to the Tethyian geoid, of course)

Posted by: elakdawalla Jul 23 2007, 01:42 PM

I say, if you walk downhill to get to the middle and uphill to get to the edge, it's a basin, no matter what it looks like from orbit! The smaller the body, the weirder the basins -- most of Itokawa's basins appear noticeably convex from above, but they are "holes" as far as local gravity is concerned.

--Emily

Posted by: Mariner9 Jul 23 2007, 03:15 PM

If using an Earth based term like "basin" on Tethys seems wrong, using it to describe features on a rubble pile like Itakowa is even furthur out of the park.

Even weirder to me was the Japanese naming one of the features on Itokawa the "Muses Sea". Although I grant you it occured to me that perhaps it was an in joke, since the Hayabusa mission was originally called "Muses C" if I recall correctly.

I think a new nomenclature is needed.

Of course, only a handful of people on Earth would ever learn it, so maybe it would just make things even more difficult than they already are.

Posted by: Phil Stooke Jul 23 2007, 04:14 PM

No, a new nomenclature is not needed! Rules of supposed logic can't be applied backwards down the line of an evolving disciplinary jargon. A basin in this context is a multi-ringed impact structure, it has nothing to do with its depth. Just as the word 'crater', originally meaning a cup, and applied to cup-shaped depressions on the Moon and Earth, can be applied to Wargentin (on the Moon) despite it being filled to the rim.

Phil

Posted by: MarcF Jul 23 2007, 05:19 PM

When I used the term "basin" for Odysseus I meant "giant impact scar".
Sorry if I misused the word.
However, I would agree with Phil when he says that it has nothing to do with its depth. Just as an example, Valhalla and Asgard on Callisto are also called basins and are almost flat. I think there are plenty of such examples in our solar system.
Marc.

Posted by: volcanopele Jul 23 2007, 05:34 PM

Exactly, Phil. What is a patera on Io isn't necessarily the same on Mars, or Venus, or Titan. Same goes with Lacus for Titan and the Moon.

Posted by: MarcF Jul 23 2007, 07:59 PM

What is this ??

http://saturn.jpl.nasa.gov/multimedia/images/raw/raw-images-details.cfm?feiImageID=116751

Marc.

Posted by: volcanopele Jul 23 2007, 08:16 PM

Tis an overexposed image of Rhea

Posted by: edstrick Jul 24 2007, 07:01 AM

<grin>

Pedantic quibbles can stir up an interesting... and relevant... discussion!

Posted by: Ken90000 Jul 24 2007, 05:42 PM

New Hyperion images are in.

There is a great crater with a central peak visible. I never knew it existed.

Posted by: elakdawalla Jul 24 2007, 05:58 PM

Whoah, those are really cool images. Phil! Help! What/where are we looking at?

Speaking of Hyperion, I just noticed this little item in today's Significant Events Report.

QUOTE

Tuesday, July 17 (DOY 198):

The final sequence development process for S34 kicked off today. The sequence is unusual in that it will be composed of four parts. The first part is similar to a normal background sequence but will run for only two weeks. This is followed by uplink and checkout activities for CDS version 10 flight software that will last for about a week and a half. During this time period there will be no science observations. After the conclusion of the CDS activities, a mini-sequence devoted to Hyperion observations will run for about four days. The last piece of S34 is again like a normal background sequence with full science activities. This will run for a little over a week, concluding on or about November 1. The Hyperion mini-sequence base products and stripped subsequences and the sequence products for the pieces of the S34 background sequence have been released for team review.

Looks like the Hyperion close approach will be within about 120,000 km on October 21; and during the second week or so of October, there'll be no science data at all.

--Emily

Posted by: Phil Stooke Jul 24 2007, 06:02 PM

You're looking at the big facet frequently seen before including in the highest resolution mosaic from the really close encounter. It's just that we have not seen such perfect low angle lighting before.

Incidentally, I don't think I ever posted this before:

It's a cylindrical mosaic of Voyager images. This new pic is of the roughly circular patch on the left side. It was made by me with the assistance of my friend Alyson Ford.

Phil

Posted by: ugordan Jul 24 2007, 06:17 PM

Wow, that lump really does look different to me every time. I wish I had a shape model of Hyperion on my desk.

3 frame rotation composed of colorized IR3 frames - these are the brightest raws available. Looks like there's no end in sight for the histogram stretcher hiccup.

Posted by: elakdawalla Jul 24 2007, 06:20 PM

Neat animation. It really lets you see Hyperion as a faceted shape rather than a body that anyone could describe as "round."

Gordan, how exactly did you colorize this?

--Emily

Posted by: volcanopele Jul 24 2007, 06:21 PM

That's Helios IIRC

Posted by: ugordan Jul 24 2007, 06:39 PM

QUOTE (elakdawalla @ Jul 24 2007, 07:20 PM)

Gordan, how exactly did you colorize this?

I used my other color shots as reference, in natural color views there's virtually no color variation anyway. I simply applied a level balance in Photoshop that reduced the max brightness of the green channel to 238 (from 255) and blue to 219, thus giving the brownish-red hue and afterwards increased the saturation a tad.

Posted by: Exploitcorporations Jul 24 2007, 09:23 PM

QUOTE (Phil Stooke @ Jul 24 2007, 11:02 AM)

I might be totally off my meds here, but I disagree. This feature looks like the prominent crater to the "southeast" (!?!) of the big facet seen during the targeted encounter (bottom center in your map). To illustrate:

I think this is the bite out of the cookie (forgive me, my 4-year-old was doing impressions of you-know-who this morning). If I'm wrong Phil, you can pummel me with rocks, preferrably irregular and faceted.

EDIT: D'oh! VP got it before I did. Unrelated bonus points in Io vs Europa deathmatch. I'll get you my pretty, if it's the last thing I do! (There's no defense against buckets of superheated sulphur. Appealing to UMSF High Council).

Posted by: elakdawalla Jul 24 2007, 09:51 PM

That's a really helpful comparison, EC. Thanks!

Emily

Posted by: Phil Stooke Jul 24 2007, 10:44 PM

You're absolutely right, EC, I had it upside down! Sorry about that. Can I get some of your meds?

Phil

Posted by: ugordan Jul 24 2007, 10:51 PM

You mean there's a "This side up" on Hyperion?

Posted by: Exploitcorporations Jul 24 2007, 10:54 PM

Sure thing! Be forewarned...upside-down won't get any better with them, but they do allow you to drive backwards. I ran over my own post fifteen minutes ago.

Edit: "This Side Up" on Hyperion remains sort of ambiguous. I suggest that Proteus is the box Hyperion came in, and that Ted has reprocessed the image enough that the lettering may finally be visible.

Posted by: Stu Jul 24 2007, 11:30 PM

Not daring for a moment to think I can compete with or compare my mucking about to the work already posted here, but I couldn't resist having a go at this Hyperion image myself, purely because it reminded me of the images DEEP IMPACT sent back from its target comet... anyone else think that?

Posted by: alan Jul 25 2007, 10:16 PM

Enceladus passing in front of Dione
http://saturn.jpl.nasa.gov/multimedia/images/raw/raw-images-details.cfm?feiImageID=117089

A short animation

Posted by: scalbers Jul 28 2007, 06:35 PM

Hi,

Quick map update for Tethys adding a medium-res image from the July encounter. I'll still want to figure out where the images in EC's hi-res mosaic (post #4) are located. Also thinking of the earlier Ithaca Chasma mosaic...

http://laps.noaa.gov/albers/sos/sos.html#TETHYS