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Pluto Surface Observations 1: NH Post-Encounter Phase, 1 Aug 2015- 10 Oct 2015
Bjorn Jonsson
post Sep 11 2015, 10:49 PM
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QUOTE (Gladstoner @ Sep 11 2015, 10:28 PM) *
The crater filled with bright material happens to be crossed by a rift that also has deposits of the white stuff on its floor (marked in red)

Just to clarify: This is an upside-down version from the same image as the one I posted earlier (and that was originally posted by Saturns Moon Titan).

But image lor_0299174617_0x630_sci_3.jpg is extremely interesting:

Attached Image


The very smooth (at least at this resolution Sputnik Planum (SP) is at lower left. But what I find particularly interesting is that equally smooth, small patches of 'SP-like' terrain occur well outside of SP. There are lots of these patches, they are of various sizes and some of them are very small.

QUOTE (stevesliva @ Sep 11 2015, 10:39 PM) *
So, why are north facing slopes white, while south-facing slopes are dark?

Could be due to sublimation and/or condensation that varies with solar elevation angle (north and east facing slopes in hi-res images of Ganymede's north polar cap are bright due apparently to water ice frost that has been cold-trapped).

EDIT In this case this seems to be mostly or entirely due to the illumination geometry rather than variable albedo.
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stevesliva
post Sep 11 2015, 10:59 PM
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QUOTE (Gladstoner @ Sep 11 2015, 05:47 PM) *
If it's not just the lighting at the moment, perhaps the 'frost' on north-facing slopes hadn't had time to burn off.


I do wonder. Contrast-stretching can do that sort of thing. But it sure looks like a real dichotomy.
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Bjorn Jonsson
post Sep 11 2015, 11:10 PM
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QUOTE (stevesliva @ Sep 11 2015, 10:59 PM) *
I do wonder. Contrast-stretching can do that sort of thing. But it sure looks like a real dichotomy.

My views on this are changing rather frequently ;-). Now I notice this nearby crater where only a part of the north-facing crater wall is bright - hardly an illumination effect:

Attached Image
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Saturns Moon Tit...
post Sep 11 2015, 11:11 PM
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QUOTE (Bjorn Jonsson @ Sep 11 2015, 11:49 PM) *
The very smooth (at least at this resolution Sputnik Planum (SP) is at lower left. But what I find particularly interesting is that equally smooth, small patches of 'SP-like' terrain occur well outside of SP. There are lots of these patches, they are of various sizes and some of them are very small.


I noticed this to the North West of Tombough Regio too


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scalbers
post Sep 11 2015, 11:16 PM
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QUOTE (Bjorn Jonsson @ Sep 11 2015, 11:10 PM) *
Now I notice this nearby crater where only a part of the north-facing crater wall is bright - hardly an illumination effect:

Trying to keep up with all that is coming in now smile.gif A quick thought is that a similar crater wall effect happens on Iapetus.


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Bjorn Jonsson
post Sep 11 2015, 11:22 PM
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Some areas on Callisto might be a possible analog too.

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Gladstoner
post Sep 11 2015, 11:24 PM
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QUOTE (Bjorn Jonsson @ Sep 11 2015, 04:49 PM) *
But image lor_0299174617_0x630_sci_3.jpg is extremely interesting:

Indeed. And in that image (rotated):

Attached Image


One of the smooth areas has texture (marked in red) that resembles certain features on Sputnik Planum that seem to resemble rafts of debris. Also, my eye caught a line of three dark smudges (yellow arrows) that seem out of place on the bright terrain.
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machi
post Sep 12 2015, 12:56 AM
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Colorized global mosaic at full resolution ~850 m/pix (9 MB png).



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JRehling
post Sep 12 2015, 01:10 AM
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QUOTE (stevesliva @ Sep 11 2015, 03:39 PM) *
So, why are north facing slopes white, while south-facing slopes are dark?


My read is that Tombaugh Regio was created in an explosion and the blast coated away-from-Tombaugh slopes white and that north-vs-south is a red herring. Of course, that may be wrong.
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jccwrt
post Sep 12 2015, 01:15 AM
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QUOTE (machi @ Sep 11 2015, 07:56 PM) *
Colorized global mosaic at full resolution ~850 m/pix (9 MB png).


This is such a spectacular image I'm having trouble just taking it all in. Fantastic!
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machi
post Sep 12 2015, 01:22 AM
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Thanks!
I found some minor flaws in the original version. Now links goes to the new version (older one isn't now available).


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Gennady Ionov
post Sep 12 2015, 04:52 AM
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QUOTE (Gladstoner @ Sep 12 2015, 03:00 AM) *
Interesting albedo boundaries:

Are these wind streaks, something caused by another process, or mere imaging artifacts?

Maybe these are streaks of dunes, drifting to the south ...
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Gennady Ionov
post Sep 12 2015, 05:04 AM
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QUOTE (Gladstoner @ Sep 12 2015, 03:16 AM) *
Fur coat!
Could these be compressional folds?


QUOTE (Bjorn Jonsson @ Sep 12 2015, 03:20 AM) *
Inside the crater this looks more like a fracture to me since it extends across the crater wall (green arrow below), apparently at variable elevation. If this was due to to some exotic river system it should extend to the crater floor but apparently it doesn't. But farther away from the crater this look more like a river system (but could still be a fracture).


I note that the cracks and folds suggest about force, which moved of Sputnik to the east. That is to say in favor of the impact formation of Sputnik by fall of the body are moving to the east.

QUOTE (Bjorn Jonsson @ Sep 12 2015, 03:49 AM) *
The very smooth (at least at this resolution Sputnik Planum (SP) is at lower left. But what I find particularly interesting is that equally smooth, small patches of 'SP-like' terrain occur well outside of SP. There are lots of these patches, they are of various sizes and some of them are very small.

And these small patches only remaining ponds from Huge water splash in the eastern direction, the flow of which led to the erosion of the surface in the east-west direction (ridges and valleys are directed from west to east).
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stevesliva
post Sep 12 2015, 05:19 AM
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QUOTE (JRehling @ Sep 11 2015, 08:10 PM) *
My read is that Tombaugh Regio was created in an explosion and the blast coated away-from-Tombaugh slopes white and that north-vs-south is a red herring. Of course, that may be wrong.


Doesn't look radial to me. Before these global mosaics I was thinking it looked like a wind of white deposition could blow out the SSW from Tombaugh Regio, but now it just looks more like Iapetus, as s.c.albers said...

With plenty of local exceptions, the trend in the southern hemisphere is South facing dark, North facing white, and the clincher is that it's not just crater slopes, but also mountain slopes.
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Charles Astro
post Sep 12 2015, 06:53 AM
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As Bjorn Jonsson noted, there are smooth patches of Sputnik Planum-like terrain in eastern half of Tombaugh Regio, sometimes called the right side of 'the heart'. I think that small patches of Sputnik Planum ice is exactly what they are. If you look closely you can see that closer to the 'shore' of Sputnik Planum there are a several channels where Sputnik Planum ice is draining out of ice lakes and down into the plain.
Attached Image

These ice lakes, as well as the coating of white ice that covers the landscape of the eastern half of Tombaugh Regio, appear to be the result of a major flood of ice out of Sputnik Planum. Ice coming up through crevasses is not enough to explain the diversity, number or wide distribution of the lakes or the uniformity of the white icy veneer over the land. A giant splash due to an asteroid impact in Sputnik Planum cannot explain the flood either, because there is another white painted region to the south of Sputnik Planum, beyond the Norgay Montes and extending over the horizon into the southern hemisphere, where exactly the same things are happening. It is implausible that 2 impacts could happen in the same spot launching giant waves in different directions. Then there is the additional fact that another ice flood appears to be rolling over the landscape to the north of Sputnik Planum, right now.

The only way I can see to explain the mystery of these multiple floods is that the crust itself must sag down, allowing Sputnik Planum ice to flow over it, then rebound causing the flood to drain away. This is amazing! It raises many more questions. It implies that the visible surface of Pluto is a crust floating over an ocean of Sputnik Planum ice. So what could the crust be made of that gives it the flexibility to deform and return, without cracking up, and a density low enough to float on Sputnik Planum ice?


QUOTE (Bjorn Jonsson @ Sep 11 2015, 03:49 PM) *
Just to clarify: This is an upside-down version from the same image as the one I posted earlier (and that was originally posted by Saturns Moon Titan).
But image lor_0299174617_0x630_sci_3.jpg is extremely interesting:
The very smooth (at least at this resolution Sputnik Planum (SP) is at lower left. But what I find particularly interesting is that equally smooth, small patches of 'SP-like' terrain occur well outside of SP. There are lots of these patches, they are of various sizes and some of them are very small. Could be due to sublimation and/or condensation that varies with solar elevation angle (north and east facing slopes in hi-res images of Ganymede's north polar cap are bright due apparently to water ice frost that has been cold-trapped).


I wonder why the New Horizons team hasn't yet gotten around to giving names to the white ice painted lobes to Sputnik planum, i.e. the right half of Tombaugh Regio and the region southward from Norgay Montes (including Norgay Montes). After all, they are 2 of Pluto's most prominent and puzzling features. http://www.ourpluto.org/maps


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