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Astronomy Picture of the Day -- Flowing Barchan Sand Dunes on Mars
NASA ^ | April 22, 2012 | (see photo credit)

Posted on 04/22/2012 8:17:03 PM PDT by SunkenCiv

Explanation: When does Mars act like a liquid? Although liquids freeze and evaporate quickly into the thin atmosphere of Mars, persistent winds may make large sand dunes appear to flow and even drip like a liquid. Visible on the above image right are two flat top mesas in southern Mars when the season was changing from Spring to Summer. A light dome topped hill is also visible on the far left of the image. As winds blow from right to left, flowing sand on and around the hills leaves picturesque streaks. The dark arc-shaped droplets of fine sand are called barchans, and are the interplanetary cousins of similar Earth-based sand forms. Barchans can move intact a downwind and can even appear to pass through each other. When seasons change, winds on Mars can kick up dust and are monitored to see if they escalate into another of Mars' famous planet-scale sand storms.

April 22, 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 04/22/2012 8:17:12 PM PDT by SunkenCiv
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To: SunkenCiv

http://cache.io9.com/assets/images/8/2012/02/xlarge_72ee311b9bd1053adeaf23ae56c6bf4c.jpg

Martian `dust bunny.’


2 posted on 04/22/2012 8:33:15 PM PDT by tumblindice (Our new, happy lives.)
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To: SunkenCiv
For a place with less than 1% of the atmosphere of the earth, that planet sure does move the dirt and dust around.

You have to wonder about the electrostatic effects.

/johnny

3 posted on 04/22/2012 8:33:58 PM PDT by JRandomFreeper (Gone Galt)
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To: SunkenCiv

Considering wind speeds on Mars can reach 400 mph for weeks at a time dunes would take on all kinds of shapes.


4 posted on 04/22/2012 8:34:46 PM PDT by jmacusa (Political correctness is cultural Marxism. I'm not a Marxist.)
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To: brytlea; cripplecreek; decimon; bigheadfred; KoRn; Grammy; married21; steelyourfaith; Mmogamer; ...

from the FRchives:

5 posted on 04/22/2012 8:41:12 PM PDT by SunkenCiv (FReepathon 2Q time -- https://secure.freerepublic.com/donate/)
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To: SunkenCiv

Freaky deaky.


6 posted on 04/22/2012 9:00:38 PM PDT by martin_fierro (< |:)~)
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To: martin_fierro

DUNE

Sand worms migrating in herds!


7 posted on 04/22/2012 9:33:56 PM PDT by BwanaNdege (Man has often lost his way, but modern man has lost his address - Gilbert K. Chesterton)
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