Cassini's Iapetus encounter 2007

The Singing Badger · Post #1by **The Singing Badger** » 10.09.2007, 17:42

Yikes. This is one lumpy moon. We're gonna need a model, not a sphere...

http://saturn1.jpl.nasa.gov/multimedia/ ... eID=126212

http://saturn1.jpl.nasa.gov/multimedia/ ... eID=126165

Post #2by **ElChristou** » 10.09.2007, 18:55

Indeed, would be nice; now the question is... do we have enough topo data to do the model?
(I fear the answer is no...

)

Hungry4info · Post #3by **Hungry4info** » 11.09.2007, 00:30

ElChristou wrote:Indeed, would be nice; now the question is... do we have enough topo data to do the model?
(I fear the answer is no... )

Yeah... I don't think we do. I think that close up, I've only seen one side of the moon. Hopefully this encounter will provide a lot of data.

lostfisherman · Post #4by **lostfisherman** » 12.09.2007, 03:29

Iapetus is a truly strange and wonderful place, going by the images coming out of Ciclops. It's like a panda moon.

http://ciclops.org/view_event.php?id=67

Why the dark regions should look as sharp as that I haven't the faintest clue.

The Singing Badger · Post #5by **The Singing Badger** » 13.09.2007, 00:15

At last! A high-res view of Iapetus's bright side. This has been a long time coming. It's amazing, some regions look like they're covered in freshly laid snow.

Iapetus must be one of the weirdest places in the solar system.

http://saturn.jpl.nasa.gov/multimedia/i ... &storedQ=0

Hungry4info · Post #6by **Hungry4info** » 13.09.2007, 22:30

lostfisherman wrote:Why the dark regions should look as sharp as that I haven't the faintest clue.

Yeah I know what you mean. At first, I thought they were shadows, but I now realise that they couldn't be.

ajtribick · Post #7by **ajtribick** » 13.09.2007, 23:07

From that image, it sort of looks like the dark stains are preferentially on slopes facing in one direction, as if something rained down on the surface from a certain angle.

But that may just be me overinterpreting the image. Even if my slopes idea is correct, the interpretation really depends how localised this effect is.

Cham · Post #8by **Cham** » 14.09.2007, 00:24

Could the dark spots be created from the temperature differences between light and shadows ? That "rain" effect you're talking about may be light from the Sun (or solar wind ?) : if the body is slowly rotating in some special periodic way, the shadows may be casted more frequently on some parts than on the rest, so the material may get less light and heat on a long run. The material is then reacting differently than the rest of the whole body. So the dark spots may be some kind of "permanent" shadows prints. Hmmm, I'm not sure this makes any sense.

LordFerret · Post #9by **LordFerret** » 14.09.2007, 01:21

I found the flow in the Rhea "Preview #3" image interesting... you'll find it on the previous month's page.
http://ciclops.org/ir_index.php?id=26

JetCrow · Post #10by **JetCrow** » 10.10.2007, 20:49

At last...
http://photojournal.jpl.nasa.gov/catalog/PIA08384

The Singing Badger · Post #11by **The Singing Badger** » 10.10.2007, 21:10

Wow!

Steve Albers has made a new Iapetus map.

http://laps.fsl.noaa.gov/albers/sos/sos.html

It'll work in Celestia if you offset it horizontally by 50%.

danielj · Post #12by **danielj** » 15.10.2007, 11:12

It is interesting,but the Steve Albers??textures are still too crude,with a lot of seams.I still waiting for someone to refine this textures.Not only Iapetus??,but also of other Saturnian moons.I don??t have computer habilities needed for it.Any volunteers?
Also,the texture works perfectly in Celestia without any offset in Geforces 6,7 and 8 because they works with non power of 2 textures,but I didn??t see if the locations match it...

The Singing Badger wrote:Wow!

Steve Albers has made a new Iapetus map.

http://laps.fsl.noaa.gov/albers/sos/sos.html

It'll work in Celestia if you offset it horizontally by 50%.

Post #13by **t00fri** » 15.10.2007, 11:27

I have updated my 4k Iapetus texture with the same new data which looks very nice ;-)

. There is not much point in going for 8k size yet.

I may show my updated texture tonight at CM.

Bye Fridger

Cham · Post #14by **Cham** » 15.10.2007, 14:42

t00fri wrote:I have updated my 4k Iapetus texture with the same new data which looks very nice . I may show my updated texture tonight at CM.

Showing the texture is one thing. Giving access to it is another. Will you release your new texture ?

Post #15by **t00fri** » 15.10.2007, 15:22

Cham wrote:
t00fri wrote:I have updated my 4k Iapetus texture with the same new data which looks very nice . I may show my updated texture tonight at CM.

Showing the texture is one thing. Giving access to it is another. Will you release your new texture ?

Cham,

I always release my work, whenever I feel it is ready according to my own quality standards. Probably one version will form the official update of my 4k iapetus texture that is located in the hires directory in CVS. I also may make a less rigorous but pleasing version available @CM that includes both bump and specmaps.

I also made a number of further new/updated textures of Saturn moons based on the official Ciclops data (Dec 2006). Notably one based on the highest resolution 16k map of Enceladus by the Ciclops imaging group. There were a large number of nasty artefacts, that I all got rid off on the weekend.

Did you want to imply that I should rather not show my iapetus texture tonight, if I don't release it at the same time? That would be easy ;-)

Bye Fridger

Post #16by **ElChristou** » 15.10.2007, 15:30

t00fri wrote:...Did you want to imply that I should rather not show my iapetus texture tonight, if I don't release it at the same time? That would be easy

Release, release, release! :wink:

Post #17by **t00fri** » 15.10.2007, 15:38

ElChristou wrote:
t00fri wrote:...Did you want to imply that I should rather not show my iapetus texture tonight, if I don't release it at the same time? That would be easy

Release, release, release!

No no, the implication was rather NOT showing, since I never hurry, with releases before I am satisfied.

F.

Post #18by **ElChristou** » 15.10.2007, 15:46

t00fri wrote:
ElChristou wrote:
t00fri wrote:...Did you want to imply that I should rather not show my iapetus texture tonight, if I don't release it at the same time? That would be easy

Release, release, release!

No no, the implication was rather NOT showing, since I never hurry, with releases before I am satisfied.

F.

Then,

show it, show it, show it!

:wink:

Cham · Post #19by **Cham** » 15.10.2007, 15:55

Thanks for the explanation, Fridger.

It's just that it happens frequently that people are showing some "finished" stuff, and teases the other users, without ever releasing it to the public. Or the delay is so long that we end forgetting about it. What gives ? Personally, I'm not really interested in seeing stuff if it's not "close enough" to the final release. And if it's never released, why showing it ? It doesn't interest me to see it shown on a web page only.

I prefer that a finished texture is announced about at the same time it is released. Or else, what gives ?

Post #20by **ElChristou** » 15.10.2007, 16:14

Cham wrote:It's just that it happens frequently that people are showing some "finished" stuff, and teases the other users, without ever releasing it to the public. Or the delay is so long that we end forgetting about it. What gives ? Personally, I'm not really interested in seeing stuff if it's not "close enough" to the final release. And if it's never released, why showing it ? It doesn't interest me to see it shown on a web page only.

Hey Cham, you say that for me or for Don Edwards? (or for both?) I see only both of us with long period before release...