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Posted by: volcanopele Dec 22 2005, 09:14 PM

As an early Christmas gift, CICLOPS and the Imaging team are pleased to announce the release of a number of Cassini images and maps as part of "Spectacular Sights from 10 AU" (though one is from near 5 AU
First up is a series of maps of the icy satellites of Saturn (Mimas, Enceladus, Tethys, Dione, Rhea, Iapetus, and Phoebe). These maps incorporate much of the new data taken over the last few months at these mostly interesting (though some dead and boring) worlds. Note however, that the Rhea data from last month's encounter has not yet been incorporated into the basemap.

http://photojournal.jpl.nasa.gov/catalog/PIA07780
http://photojournal.jpl.nasa.gov/catalog/PIA07776
http://photojournal.jpl.nasa.gov/catalog/PIA07781
http://photojournal.jpl.nasa.gov/catalog/PIA07771
http://photojournal.jpl.nasa.gov/catalog/PIA07779
http://photojournal.jpl.nasa.gov/catalog/PIA07778
http://photojournal.jpl.nasa.gov/catalog/PIA07775

But that's not all! Also included in this release are some great images of Saturn and Titan in color and a movie of Rhea and Dione.

http://photojournal.jpl.nasa.gov/catalog/PIA07771
http://photojournal.jpl.nasa.gov/catalog/PIA07772
http://photojournal.jpl.nasa.gov/catalog/PIA07774
http://photojournal.jpl.nasa.gov/catalog/PIA07770

http://photojournal.jpl.nasa.gov/catalog/PIA07773

Enjoy!

Posted by: volcanopele Dec 22 2005, 09:23 PM

Okay, somethings going funky at the Photojournal. The basemaps can be found at http://ciclops.org/view_event.php?id=48 .

Here are the Ciclops links:

* http://ciclops.org/view.php?id=1089
* http://ciclops.org/view.php?id=1474
* http://ciclops.org/view.php?id=1086
* http://ciclops.org/view.php?id=1732
* http://ciclops.org/view.php?id=1112

Posted by: odave Dec 22 2005, 10:01 PM

Seeing that image of Dione - it just blows my mind that I can see something that small, that far away, in a backyard telescope. I guess that's albedo at work

Thanks for the presents, CICLOPS team!

Posted by: ugordan Dec 22 2005, 10:05 PM

There's nothing funky, it's quite common for them to take some time to update/refresh/sort-out the database.
There were a number of times when an image appeared on the Cassini home page, linking to the Photojournal, yet the latter said no such entry existed.

Posted by: JRehling Dec 22 2005, 10:05 PM

You can really tell how much it helps to be 10 AU closer to it...

Posted by: Tman Dec 22 2005, 10:06 PM

Wow! Again two beautys of Saturn!
I love this blue behind the shadows.

A nice fluently show from Rhea and Dione too
"...a scheme called interpolation" ...means that those additional frames between the original pics are copys of the left and right originals. I guess there have to be a lot of them between.

Posted by: ugordan Dec 22 2005, 10:10 PM

I, on the other hand, don't very much appreciate the interpolations like this. Especially since they seem to be done using the nearest neighbor method. They make the whole thing seem "false". I didn't like it on the Hyperion anim, didn't like it on the recent Iapetus anim and still don't like it.
Give me animation frames as they were originally taken is what I say


How do you know it wasn't in fact several AU farther?

Posted by: Tman Dec 22 2005, 10:16 PM

Ok, but then you have to shoot a lot of pics every seconds to get such a fluently show. Or the next generation of spacecrafts should carry a webcam behind the telescope

Posted by: ugordan Dec 22 2005, 10:19 PM

Hear, hear!

Posted by: JRehling Dec 22 2005, 10:38 PM

Then it would look smaller.

Posted by: Fraggler Dec 23 2005, 12:11 AM

I believe the interpolation is actually done by animating slices of the original frames. Take for example this eclipse movie... Dione is sliced out of each frame and that slice is shifted along a path in the interpolated frames creating the illusion of motion without actually messing with the individual pixels. By this method each movie frame, interpolated or not, has pixels values from an actual image of Dione and Rhea though the positions of the two bodies relative to each other changes.

Posted by: ljk4-1 Dec 23 2005, 05:16 AM

Here's a beautiful image:

http://photojournal.jpl.nasa.gov/catalog/PIA07772

Original Caption Released with Image:

Few sights in the solar system are more strikingly beautiful than softly hued Saturn embraced by the shadows of its stately rings.

The gas planet's subtle northward gradation from gold to azure is a striking visual effect that scientists don't fully understand. Current thinking says that it may be related to seasonal influences, tied to the cold temperatures in the northern (winter) hemisphere. Despite Cassini's revelations, Saturn remains a world of mystery.

Currently, the rings' shadows shield the mid-northern latitudes from the harshest of the sun's rays. As Saturn travels around the sun in its 29-year orbit, the shadows will narrow and head southward, eventually blanketing the opposite hemisphere.

Images taken with blue, green and red spectral filters were used to create this color view, which approximates the scene as it would appear to the human eye. The view was brightened to enhance detail visible in the rings and within their shadows.

The images were obtained with the Cassini wide-angle camera from a distance of approximately 999,000 kilometers (621,000 miles) from Saturn on May 4, 2005, as the spacecraft cruised a few degrees above the ring plane. The image scale is about 60 kilometers (37 miles) per pixel on Saturn.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.

For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov. The Cassini imaging team homepage is at http://ciclops.org.

Image Credit:

NASA/JPL/Space Science Institute

Posted by: ugordan Dec 23 2005, 07:59 AM

Yes, but the end result is jerky nonetheless. While there was no resizing in this particular animation, both the Hyperion and Iapetus, maybe even Dione (haven't looked at that one in a while) anims do involve resizing and it's very obvious it's a pretty lousy algorithm one would expect from simple Flash animations.

Posted by: Tman Dec 23 2005, 10:31 AM

Yeah, think so too. The MPEG is very cloudy but the QT-movie is nice: http://ciclops.org/view.php?id=1732&flash=1 Dione shows in the 37 original pics no visible change during the sequence, so it's acceptable to put copys between. Btw. I count ~300 frames in the QT-movie

Apropos change, in the normal GIF sequence you can catch a small turn of Rhea:
(1,0 MB) http://www.greuti.ch/cassini/eclipse_rhea-dione2.gif

Posted by: jmknapp Dec 23 2005, 11:55 AM

That's just terrific. I downloaded one map at full res & it's 14960x7860! Great to zoom in on areas and see so much detail.

As for Christmas proper, ISS-wise, here's a possible Christmas "Tiny Tim" (don't know if it's planned):

date/timeUTC/moon/distanceKM/%NAC FOV

DEC25 00:45 TELESTO 21,499 25%

And another little guy on Christmas eve?

DEC24 20:48 PROMETHEUS 138,000 17%

I believe the best resolution of Prometheus to date was from 4x further away. How about letting him in on the reindeer games?