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AMAZING pictures of Saturn from Cassini (Dialup warning)

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n2doc Donating Member (1000+ posts) Send PM | Profile | Ignore Thu Oct-12-06 07:34 AM
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AMAZING pictures of Saturn from Cassini (Dialup warning)

With giant Saturn hanging in the blackness and sheltering Cassini from the sun's blinding glare, the spacecraft viewed the rings as never before, revealing previously unknown faint rings and even glimpsing its home world.

This marvelous panoramic view was created by combining a total of 165 images taken by the Cassini wide-angle camera over nearly three hours on Sept. 15, 2006. The full mosaic consists of three rows of nine wide-angle camera footprints; only a portion of the full mosaic is shown here. Color in the view was created by digitally compositing ultraviolet, infrared and clear filter images and was then adjusted to resemble natural color.

The mosaic images were acquired as the spacecraft drifted in the darkness of Saturn's shadow for about 12 hours, allowing a multitude of unique observations of the microscopic particles that compose Saturn's faint rings.

Ring structures containing these tiny particles brighten substantially at high phase angles: i.e., viewing angles where the sun is almost directly behind the objects being imaged.

During this period of observation Cassini detected two new faint rings: one coincident with the shared orbit of the moons Janus and Epimetheus, and another coincident with Pallene's orbit. (See PIA08322 and PIA08328 for more on the two new rings.)

The narrowly confined G ring is easily seen here, outside the bright main rings. Encircling the entire system is the much more extended E ring. The icy plumes of Enceladus, whose eruptions supply the E ring particles, betray the moon's position in the E ring's left-side edge.

Interior to the G ring and above the brighter main rings is the pale dot of Earth. Cassini views its point of origin from over a billion kilometers (and close to a billion miles) away in the icy depths of the outer solar system. See PIA08324 for a similar view of Earth taken during this observation.

Small grains are pushed about by sunlight and electromagnetic forces. Hence, their distribution tells much about the local space environment.

A second version of the mosaic view is presented here in which the color contrast is greatly exaggerated. In such views, imaging scientists have noticed color variations across the diffuse rings that imply active processes sort the particles in the ring according to their sizes.

Looking at the E ring in this color-exaggerated view, the distribution of color across and along the ring appears to be different between the right side and the left. Scientists are not sure yet how to explain these differences, though the difference in phase angle between right and left may be part of the explanation. The phase angle is about 179 degrees on Saturn.

The main rings are overexposed in a few places.

This view looks toward the unlit side of the rings from about 15 degrees above the ringplane.

Cassini was approximately 2.2 million kilometers (1.3 million miles) from Saturn when the images in this mosaic were taken. Image scale on Saturn is about 260 kilometers (162 miles) per pixel.





This NASA image shows a false-color mosaic of Saturn showing deep-level clouds silhouetted against the planet's glowing interior. The image was made with data from Cassini's visual and infrared mapping spectrometer, which can image the planet at 352 different wavelengths. This mosaic shows the entire planet, including features like Saturn's ring shadows and the terminator, the boundary between day and night.


Saturn's D ring--the innermost of the planet's rings--sports an intriguing structure that appears to be a wavy, or "vertically corrugated," spiral. This continuously changing ring structure provides circumstantial evidence for a possible recent collision event in the rings.
Support for this idea comes from the appearance of a structure in the outer D-ring that looks, upon close examination, like a series of bright ringlets with a regularly spaced interval of about 30 kilometers (19 miles). When viewed along a line of sight nearly in the ringplane, a pattern of brightness reversals is observed: a part of the ring that appears bright on the far side of the rings appears dark on the near side of the rings, and vice versa (see D Ring Sight Lines).

This phenomenon would occur if the region contains a sheet of fine material that is vertically corrugated, like a tin roof. In this case, variations in brightness would correspond to changing slopes in the rippled ring material (see image with inset graphic). An observation made with NASA's Hubble Space Telescope in 1995 also saw a periodic structure in the outer D ring, but its wavelength was then 60 kilometers (37 miles). There were insufficient observations to discern the spiral nature of the feature. Thus, it appears the wavelength of the wavy structure has been decreasing: that is, this feature has been winding up like a spring over time.


more: (The full res versions of the first image are incredible!)
http://photojournal.jpl.nasa.gov/catalog/PIA08329
and
http://saturn.jpl.nasa.gov/home/index.cfm
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Nimrod2005 Donating Member (1000+ posts) Send PM | Profile | Ignore Thu Oct-12-06 07:37 AM
Response to Original message
1. Wow......Amazing and beautiful in a way.
Thanks for sharing...
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Tom Joad Donating Member (1000+ posts) Send PM | Profile | Ignore Thu Oct-12-06 07:43 AM
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2. Saturn is always beautiful this time of year.
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SlavesandBulldozers Donating Member (1000+ posts) Send PM | Profile | Ignore Thu Oct-12-06 09:27 PM
Response to Reply #2
8. lol
great time for a walk on the beach aside the ocean of ammonia.
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Tom Joad Donating Member (1000+ posts) Send PM | Profile | Ignore Thu Oct-12-06 10:06 PM
Response to Reply #8
12. It actually is the height of the tourist season, but i had hoped to
keep it a secret.
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AIJ Alom Donating Member (1000+ posts) Send PM | Profile | Ignore Thu Oct-12-06 07:47 AM
Response to Original message
3. The world that awaits and beckons us out there while we try to deal with
the short narrow minded war mongers here fighting over this insignificant small spot. Imagine all the other wonders that await us. Sigh. Here's to hoping for a brighter tomorrow.
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Psephos Donating Member (1000+ posts) Send PM | Profile | Ignore Thu Oct-12-06 08:55 AM
Response to Original message
4. Fabulous! Thanks. n/t
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Bill McBlueState Donating Member (1000+ posts) Send PM | Profile | Ignore Thu Oct-12-06 09:55 AM
Response to Original message
5. those really are amazing
These pics serve as a reminder why it's good to invest some of our tax money in space exploration.
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JimDandy Donating Member (1000+ posts) Send PM | Profile | Ignore Thu Oct-12-06 09:04 PM
Response to Reply #5
7. And a reminder of something bigger than the squalid political heavings
Edited on Thu Oct-12-06 09:05 PM by JimDandy
of mother earth. Thanks.
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daninthemoon Donating Member (1000+ posts) Send PM | Profile | Ignore Thu Oct-12-06 08:37 PM
Response to Original message
6. These are beautiful. Thank you!!!
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Straight Shooter Donating Member (1000+ posts) Send PM | Profile | Ignore Thu Oct-12-06 09:45 PM
Response to Original message
9. I hope I never become indifferent to the wonders of our universe.
Absolutely sublime beauty. Thank you so much for sharing this with us.
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Az_lefty Donating Member (1000+ posts) Send PM | Profile | Ignore Thu Oct-12-06 09:45 PM
Response to Original message
10. Wow! amazingly better than what I can see through my Oberwerk bino's
by orders of magnitude....
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ovidsen Donating Member (1000+ posts) Send PM | Profile | Ignore Thu Oct-12-06 09:50 PM
Response to Original message
11. Just gorgeous! Thanks K&R n/t
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SlavesandBulldozers Donating Member (1000+ posts) Send PM | Profile | Ignore Thu Oct-12-06 10:09 PM
Response to Original message
13. anyone know why images in space have to be
amalgamations of various images, and not "actuals". like when they take a picture of a galaxy typically its computer hypothesized or otherwise not actual. why is that?
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n2doc Donating Member (1000+ posts) Send PM | Profile | Ignore Fri Oct-13-06 07:32 AM
Response to Reply #13
14. It has to do with the size of the images that the camera can take
They are using their "wide field" camera, but even so at the distance Cassini is from Saturn, it only captures a small part of the planet. It is like trying to take a picture of a mountain while standing at its base. If they were further out they could get the whole planet in (there are examples of this on the site) but there would not be as much detail.
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SlavesandBulldozers Donating Member (1000+ posts) Send PM | Profile | Ignore Sat Oct-14-06 10:24 AM
Response to Reply #14
17. Thanks!
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Tesha Donating Member (1000+ posts) Send PM | Profile | Ignore Fri Oct-13-06 11:31 AM
Response to Reply #13
15. Casini is probably too close to get the whole thing "in view" at once.
Plus, its sensor has limited resolution. So if you want
more pixels (for a really finely detailed image), you need
to use those pixels on the sensor more than once.

Plus it lets you accommodate a wider range of brightness;
longer exposures on the dimmer parts, shorter (or stopped-down)
on the brighter.

With regard to the galaxy: From where would you take an
"actual" picture?

Tesha
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SlavesandBulldozers Donating Member (1000+ posts) Send PM | Profile | Ignore Sat Oct-14-06 10:23 AM
Response to Reply #15
16. thanks!
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