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Astronomy Picture of the Day -- Dark Sand Cascades on Mars
NASA ^ | November 25, 2012 | (see photo credit)

Posted on 11/26/2012 7:25:19 PM PST by SunkenCiv

Explanation: They might look like trees on Mars, but they're not. Groups of dark brown streaks have been photographed by the Mars Reconnaissance Orbiter on melting pinkish sand dunes covered with light frost. The above image was taken in 2008 April near the North Pole of Mars. At that time, dark sand on the interior of Martian sand dunes became more and more visible as the spring Sun melted the lighter carbon dioxide ice. When occurring near the top of a dune, dark sand may cascade down the dune leaving dark surface streaks -- streaks that might appear at first to be trees standing in front of the lighter regions, but cast no shadows. Objects about 25 centimeters across are resolved on this image spanning about one kilometer. Close ups of some parts of this image show billowing plumes indicating that the sand slides were occurring even when the image was being taken.

November 25, 2012

(Excerpt) Read more at 129.164.179.22 ...


TOPICS: Astronomy; Astronomy Picture of the Day; Science
KEYWORDS: apod; astronomy; mars; science
[Credit: HiRISE, MRO, LPL (U. Arizona), NASA]

1 posted on 11/26/2012 7:25:30 PM PST by SunkenCiv
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To: brytlea; cripplecreek; decimon; bigheadfred; KoRn; Grammy; married21; steelyourfaith; Mmogamer; ...

2 posted on 11/26/2012 7:26:21 PM PST by SunkenCiv (https://secure.freerepublic.com/donate/)
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To: SunkenCiv

I so much love that photo, I almost want a copy to frame to hang on a wall!


3 posted on 11/26/2012 7:30:39 PM PST by onyx (FREE REPUBLIC IS HERE TO STAY! DONATE MONTHLY! IF YOU WANT ON SARAH PALIN''S PING LIST, LET ME KNOW)
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To: SunkenCiv

Oil or tar on Mars??

Is that possible without decayed carbon based plants??

Enquiring minds, etc.


4 posted on 11/26/2012 7:38:32 PM PST by Noob1999 (Loose Lips, Sink Ships)
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To: onyx

how many miles does that cover?


5 posted on 11/26/2012 7:39:34 PM PST by GeronL (http://asspos.blogspot.com)
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To: SunkenCiv

Where’s that BIG BIG BIGGER THAN BIG news they promised us last week?


6 posted on 11/26/2012 7:42:33 PM PST by DManA
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To: SunkenCiv

Looks like some funky cheese in my refrigerator.


7 posted on 11/26/2012 7:47:17 PM PST by fieldmarshaldj (Resist We Much)
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To: onyx

No kidding. That’s cool!


8 posted on 11/26/2012 7:53:55 PM PST by colinhester
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To: colinhester

Truly!


9 posted on 11/26/2012 8:02:53 PM PST by onyx (FREE REPUBLIC IS HERE TO STAY! DONATE MONTHLY! IF YOU WANT ON SARAH PALIN''S PING LIST, LET ME KNOW)
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To: onyx
Looks cold. Article doesn't say whether the frost is H2O or CO. Either way... Pretty as it looks, I'd say put some Christmas lights on it, and go back to where it's warm. Don't expect the lights to look nice if I have to put them out. ;)

/johnny

10 posted on 11/26/2012 8:16:16 PM PST by JRandomFreeper (Gone Galt)
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CO should be CO2. Doh!


11 posted on 11/26/2012 8:17:46 PM PST by JRandomFreeper (Gone Galt)
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To: SunkenCiv
I bet NASA is going to say that this isn't a lake on Mars.



And these aren't trees or bushes.


12 posted on 11/26/2012 8:24:31 PM PST by Jack Hydrazine (It's the end of the world as we know it and I feel fine!)
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To: Jack Hydrazine
By no means land a rover there!!!
Could get hung up in the trees :)
13 posted on 11/26/2012 8:32:02 PM PST by The Cajun (Sarah Palin, Mark Levin......Nuff said.)
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To: SunkenCiv

“Objects about 25 centimeters across are resolved on this image spanning about one kilometer”

I hate when they use these measurements because I have no idea what they mean. I cannot get any idea of the size I am looking at.

And their explanation, although I’m sure correct, does not seem correct. The dark stains appear to be standing freely in the air and do not look at all as if they are sliding down a sand dune.

Useless to me.


14 posted on 11/26/2012 9:03:46 PM PST by Beowulf9
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To: SunkenCiv

Great find! Thanks!


15 posted on 11/26/2012 9:38:07 PM PST by Graewoulf ((Traitor John Roberts' Obama"care" violates Sherman Anti-Trust Law, AND the U.S. Constitution.))
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To: JRandomFreeper

I haven’t given any thought to the temperature.
I remain captivated by the photo.


16 posted on 11/26/2012 10:26:12 PM PST by onyx (FREE REPUBLIC IS HERE TO STAY! DONATE MONTHLY! IF YOU WANT ON SARAH PALIN''S PING LIST, LET ME KNOW)
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To: Beowulf9
The picture frame is about a half mile across. Every pixel is about 10 inches. If I did my sums right. I'm just a cook.

Interpreting overhead photographs requires a rather long school in the US military.

Lots of pitfalls and tricks to it. What you think you see might not be reality on the ground.

johnny

17 posted on 11/26/2012 10:34:35 PM PST by JRandomFreeper (Gone Galt)
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To: SunkenCiv

Looks like a Martian ski slope.


18 posted on 11/26/2012 11:49:15 PM PST by Ken H
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To: JRandomFreeper
Article doesn't say whether the frost is H2O or CO

Actually the article does say. It is CO2 ice.

19 posted on 11/27/2012 12:15:44 AM PST by calex59
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To: SunkenCiv

Very cool. I set it as my new desktop. Replaces the ‘moonbow waterfall’ pic of last week(?). Thanks.


20 posted on 11/27/2012 12:42:31 AM PST by Tainan (Cogito, ergo conservatus sum -- "The Taliban is inside the building")
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To: GeronL

One kilometer.


21 posted on 11/27/2012 3:07:07 AM PST by TheOldLady
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To: SunkenCiv

Mars has eyelashes? Cool.


22 posted on 11/27/2012 3:08:34 AM PST by TheOldLady
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To: calex59
Thanks. I missed that first time around.

I just bumped the heat up here. Just looking at it makes me shiver. ;)

/johnny

23 posted on 11/27/2012 7:15:37 AM PST by JRandomFreeper (Gone Galt)
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To: SunkenCiv

Wait a minute, now; carbon dioxide ice? But every AGW proponent swears that CO2 causes warming, whats up with the dry ice? < /sarc >


24 posted on 11/27/2012 10:36:41 AM PST by JimRed (Excise the cancer before it kills us; feed &water the Tree of Liberty! TERM LIMITS, NOW & FOREVER!)
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