APOD: Enceladus Backlit by Saturn (2012 Feb 08)

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APOD: Enceladus Backlit by Saturn (2012 Feb 08)

Post by APOD Robot » Wed Feb 08, 2012 5:05 am

Image Enceladus Backlit by Saturn

Explanation: This moon is shining by the light of its planet. Specifically, a large portion of Enceladus pictured above is illuminated primarily by sunlight first reflected from the planet Saturn. The result is that the normally snow-white moon appears in the gold color of Saturn's cloud tops. As most of the illumination comes from the image left, a labyrinth of ridges throws notable shadows just to the right of the image center, while the kilometer-deep canyon Labtayt Sulci is visible just below. The bright thin crescent on the far right is the only part of Enceladus directly lit by the Sun. The above image was taken last year by the robotic Cassini spacecraft during a close pass by by the enigmatic moon. Inspection of the lower part of this digitally sharpened image reveals plumes of ice crystals thought to originate in a below-surface sea.

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Re: APOD: Enceladus Backlit by Saturn (2012 Feb 08)

Post by geckzilla » Wed Feb 08, 2012 5:23 am

Wow...
Just call me "geck" because "zilla" is like a last name.

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Re: APOD: Enceladus Backlit by Saturn (2012 Feb 08)

Post by Flase » Wed Feb 08, 2012 5:57 am

This is a wonderful picture, but it is too cropped. It would be more artistically and æsthetically pleasing if there were significant space around it.

I imagine travelling towards it and landing at a moon base on its surface...

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Re: APOD: Enceladus Backlit by Saturn (2012 Feb 08)

Post by Chris Peterson » Wed Feb 08, 2012 6:04 am

Flase wrote:This is a wonderful picture, but it is too cropped. It would be more artistically and æsthetically pleasing if there were significant space around it.
Technically, I don't think it's "cropped" at all. The image is the same size as the sensor, so I think the edges were determined by the actual field of view of the camera. Of course, that's what you'd like to maximize the information content... but as you say, it isn't what we see as most aesthetic.
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Re: APOD: Enceladus Backlit by Saturn (2012 Feb 08)

Post by Ann » Wed Feb 08, 2012 6:23 am

Enceladus is a most fascinating moon. That extremely deep canyon, Labtayt Sulci, looks incredible. I can actually imagine warm water coming out of this canyon, or at least being on the verge of breaking through the bottom of the canyon and gushing out.

Another incredible thing about Enceladus is that it is very smooth on a larger scale, but on smaller scales, the ones we humans would have to negotiate if we (or more likely, one of our unmanned probes) were to land on Enceladus, this small icy moon is incredibly uneven, with deep, deep cracks and high ice cliffs everywhere.

You can actually see that Enceladus is more cratered near its north pole than near its south pole, where all that water vapor is coming out and slowly blotting out the nearby craters. It's fantastic that you can truly see some of that water vapor in this image.

What a strange, incredible moon this is.

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Re: APOD: Enceladus Backlit by Saturn (2012 Feb 08)

Post by Mars HQ » Wed Feb 08, 2012 9:45 am

What an absolutely stunning photo. Congratulations to this spaceship's mission and all involved with her success to date. Seriously, how much more mind-blowing science has been revealed to mankind by this single probe, than arguably all findings associated with the ISS thus far?!? Cost wise, these probes and deep-space sensors seem to be the most meaningful and valued asset to discovery within the solar system. As such, I truly hope such assets and future projects are not pushed aside in favor of any potential, frenzied 'race' to Mars as exciting as a multi-national manned base would be one day.

Anyway, I have one question with regards to this Image of Enceladus. If one looks at the Northern-central and Northern right sections of the image there appears to be at least 4 diamond shaped craters? Anyone else see these? One of which seems very profound and consists of a fairly defined, multi-layered inner mound too. Very fascinating symetrical shapes really. So I'm curious, what would cause such symetrical diamond crater walls to form? Some form of angular wind blown effect over time? Any input would be appreciated, thanks in advance.

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Re: APOD: Enceladus Backlit by Saturn (2012 Feb 08)

Post by zaragon » Wed Feb 08, 2012 10:26 am

I have e question!

Why are there almost only craters around the north pole? I see almost none around the equator and none around the south pole (I'm guessing north is "up" on the photo and south is "down"). How come?

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Re: APOD: Enceladus Backlit by Saturn (2012 Feb 08)

Post by Flase » Wed Feb 08, 2012 11:36 am

Mars HQ wrote:What an absolutely stunning photo. Congratulations to this spaceship's mission and all involved with her success to date. Seriously, how much more mind-blowing science has been revealed to mankind by this single probe, than arguably all findings associated with the ISS thus far?!? Cost wise, these probes and deep-space sensors seem to be the most meaningful and valued asset to discovery within the solar system. As such, I truly hope such assets and future projects are not pushed aside in favor of any potential, frenzied 'race' to Mars as exciting as a multi-national manned base would be one day.
The Huygens probe also gave us amazing images. It's a shame it didn't last very long.
Mars HQ wrote:Anyway, I have one question with regards to this Image of Enceladus. If one looks at the Northern-central and Northern right sections of the image there appears to be at least 4 diamond shaped craters? Anyone else see these? One of which seems very profound and consists of a fairly defined, multi-layered inner mound too. Very fascinating symetrical shapes really. So I'm curious, what would cause such symetrical diamond crater walls to form? Some form of angular wind blown effect over time? Any input would be appreciated, thanks in advance.
My personal guess is a sort of plate tectonics like the skin on hot milk that bunches up into straightish lines.
Last edited by owlice on Wed Feb 08, 2012 12:13 pm, edited 1 time in total.
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Re: APOD: Enceladus Backlit by Saturn (2012 Feb 08)

Post by Indigo_Sunrise » Wed Feb 08, 2012 11:57 am

Incredibly detailed, beautiful image! Brilliant!

(Can't believe I've missed this one! I try to visit the Cassini Image Site frequently.)


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Re: APOD: Enceladus Backlit by Saturn (2012 Feb 08)

Post by orin stepanek » Wed Feb 08, 2012 1:23 pm

Wow! What a shot; made possible by Cassini! 8-)
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Re: APOD: Enceladus Backlit by Saturn (2012 Feb 08)

Post by Steve Dutch » Wed Feb 08, 2012 2:03 pm

Cassini just continues to amaze. It has been the most brilliantly flawless mission in the history of space exploration.

I like the "ghost" craters at upper right below the prominent deep pair. Evidently craters get buried by ice impact debris or ice eruptions, or simply flatten out as the icy crust relaxes.

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Re: APOD: Enceladus Backlit by Saturn (2012 Feb 08)

Post by bactame » Wed Feb 08, 2012 2:15 pm

A subterranean ocean and icy crust must be giving Jules Verne travel plan dreams.

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Re: APOD: Enceladus Backlit by Saturn (2012 Feb 08)

Post by Boomer12k » Wed Feb 08, 2012 2:47 pm

Magnificent picture!
Ok, here is one for you...just right of center is a big bunch of lines, above the north end of the canyon. Why does it look like a stick figure of a man plowing in a field?
Either that or it looks like a Chinese letter....

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Re: APOD: Enceladus Backlit by Saturn (2012 Feb 08)

Post by jinger » Wed Feb 08, 2012 4:03 pm

Skiers, get your poles ready: Saturn's moon Enceladus appears to be cloaked in drifts of powdery snow around 330 feet (100 meters) thick
http://news.nationalgeographic.com/news ... -enceladus

the moon Enceladus is the best candidate for finding simple organisms in the solar system in our lifetime
http://www.pbs.org/wgbh/nova/space/life ... ladus.html

If you get a chance, I highly recommend the NOVA episode Finding Life Beyond Earth -- just for the CGI walkthroughs of what it might be like to walk around on Enceladus and Titan.

mugsy

Re: APOD: Enceladus Backlit by Saturn (2012 Feb 08)

Post by mugsy » Wed Feb 08, 2012 5:02 pm

Interesting that what would appear as the northern hemishere is littered with crators whereas the rest of this moon is almost devoid of cratering. This picture would also almost make one think that ice had melted from the north pole and flowed south ,splitting into two main water systems which creates the canyons. At the southern end of the canyons it appears that liquid water has again frozen in the delta areas. Just my opinion of what I see. Interesting.

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Re: APOD: Enceladus Backlit by Saturn (2012 Feb 08)

Post by Chris Peterson » Wed Feb 08, 2012 5:20 pm

mugsy wrote:Interesting that what would appear as the northern hemishere is littered with crators whereas the rest of this moon is almost devoid of cratering. This picture would also almost make one think that ice had melted from the north pole and flowed south ,splitting into two main water systems which creates the canyons. At the southern end of the canyons it appears that liquid water has again frozen in the delta areas. Just my opinion of what I see. Interesting.
There is a lot of complex stuff going on. The moon is tectonically active, so you have a lot of resurfacing going on from that. It's also made mostly of ice, which undergoes viscous flow over (geologically) short time spans, which also results in resurfacing. It is tidally locked to Saturn, so it has permanent leading and trailing edges in its orbit, which means there will be an inherent asymmetry in cratering, and also in surface composition. And because there are probably instabilities in its interaction with the rings, there may well be periods of increased cratering which occur semi-periodically.

All in all, not an easy object to understand.
Chris

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Saturn shine (Re: APOD: Enceladus Backlit by Saturn)

Post by Anthony Barreiro » Wed Feb 08, 2012 6:04 pm

This is a beautiful image. I love the analogy to Earthshine on our Moon, "the old Moon in the arms of the new." Thanks to everyone for more info about the dynamics of Enceladus' surface.
May all beings be happy, peaceful, and free.

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Re: APOD: Enceladus Backlit by Saturn (2012 Feb 08)

Post by Flase » Wed Feb 08, 2012 10:38 pm

Boomer12k wrote:Magnificent picture!
Ok, here is one for you...just right of center is a big bunch of lines, above the north end of the canyon. Why does it look like a stick figure of a man plowing in a field?
Either that or it looks like a Chinese letter...
As long as it doesn't look like a french letter

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Re: APOD: Enceladus Backlit by Saturn (2012 Feb 08)

Post by TNT » Wed Feb 08, 2012 11:06 pm

It looks like the Moon, just without those gulleys. I like it.
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Re: APOD: Enceladus Backlit by Saturn (2012 Feb 08)

Post by biddie67 » Thu Feb 09, 2012 12:06 am

What a great picture of a fascinating and intriguing moon ~~ are there any cousins of the little rovers that can be sent here?

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Re: APOD: Enceladus Backlit by Saturn (2012 Feb 08)

Post by starstruck » Thu Feb 09, 2012 7:08 am

This is what a billiards/pool cue ball might look like when it gets really really really old . .

. . this one looks like it played one game too many