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Astronomy Picture of the Day - Dark Sand Cascades on Mars
NASA ^ | 29 Jun, 2025 | Image Credit: NASA, HiRISE, MRO, LPL (U. Arizona),

Posted on 06/29/2025 5:09:38 PM PDT by MtnClimber

Explanation: Are these trees growing on Mars? No. Groups of dark brown streaks have been photographed by the Mars Reconnaissance Orbiter on melting pinkish sand dunes covered with light frost. The featured 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 while the image was being taken.


TOPICS: Astronomy; Astronomy Picture of the Day; Science
KEYWORDS: apod; nasa

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To be added or removed from the Astronomy Picture of the Day ping list please send me a request via "Private Reply" (Mail).

For more detail go to the link and click on the image for a high definition image. You can then move the magnifying glass cursor then click to zoom in and click again to zoom out. When zoomed in you can scan by moving the side bars on the bottom and right side of the image.

1 posted on 06/29/2025 5:09:38 PM PDT by MtnClimber
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To: MtnClimber

2 posted on 06/29/2025 5:10:07 PM PDT by MtnClimber (For photos of scenery, wildlife and climbing, click on my screen name for my FR home page.)
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To: 21stCenturion; 21twelve; 4everontheRight; A Navy Vet; A_perfect_lady; abb; AFB-XYZ; AFPhys; ...
Pinging the APOD list

🪐 🌟 🌌 🍔

3 posted on 06/29/2025 5:11:02 PM PDT by MtnClimber (For photos of scenery, wildlife and climbing, click on my screen name for my FR home page.)
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To: MtnClimber

That photo is bizarre.


4 posted on 06/29/2025 5:19:13 PM PDT by GaltAdonis
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To: MtnClimber
That photo is bizarre.
Thanks for posting.

Anybody ever watch the movie ‘Robinson Crusoe on Mars’?
Decades ago it used to be on Saturday Morning TV frequently.

5 posted on 06/29/2025 5:22:17 PM PDT by GaltAdonis
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To: MtnClimber

Way cool!


6 posted on 06/29/2025 5:25:57 PM PDT by Jet Jaguar
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To: MtnClimber

Giant sand fleas.


7 posted on 06/29/2025 5:27:08 PM PDT by AFB-XYZ (( We have two options: 1. Stand up, or 2. Bend over))
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To: GaltAdonis

Yep. A pretty good flick that one.
Even the Martian believed in God, Kahichopek IIRC


8 posted on 06/29/2025 5:36:41 PM PDT by mitch5501 ("make your calling and election sure:for if ye do these things ye shall never fall")
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To: GaltAdonis

Saw it at the theater, iirc.


9 posted on 06/29/2025 5:37:05 PM PDT by BenLurkin (The above is not a statement of fact. It is opinion or satire. Or both.)
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To: MtnClimber

It almost looks otherworldly.


10 posted on 06/29/2025 5:39:22 PM PDT by HandyDandy (“Borders, language and culture.” Michael Savage)
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To: GaltAdonis

I didn’t see Robinson Crusoe but I saw John Carter of Mars.


11 posted on 06/29/2025 5:44:48 PM PDT by BipolarBob (If people make you sick, maybe you should try cooking them longer.)
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To: HandyDandy

That’s a good way of describing it.


12 posted on 06/29/2025 5:45:33 PM PDT by BipolarBob (If people make you sick, maybe you should try cooking them longer.)
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To: BipolarBob
Robinson Crusoe on Mars
Made in 1964 - (The special effects are king of comical.)

https://pluto.tv/us/on-demand/movies/67c8bf8a75fa845700721237?utm_medium=textsearch&utm_source=google

13 posted on 06/29/2025 5:54:01 PM PDT by GaltAdonis
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To: BipolarBob

Martians are known for their dry sense of humor.


14 posted on 06/29/2025 6:06:20 PM PDT by HandyDandy (“Borders, language and culture.” Michael Savage)
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To: GaltAdonis

Looks like a colage of Jabba the Hutt to me.


15 posted on 06/29/2025 6:09:33 PM PDT by Pocketdoor
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To: GaltAdonis

John Carter based on Edgar Rice Burroughs novel(ettes). Made in 2012 cost $250,000,000 and raked in a paltry 30 mil the first week of showing. It eventually made their money back but was considered a flop financially.


16 posted on 06/29/2025 6:12:22 PM PDT by BipolarBob (If people make you sick, maybe you should try cooking them longer.)
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To: HandyDandy

That’s just pun-derful. I’d like to go to Mars, not for the people but just for the atmosphere.


17 posted on 06/29/2025 6:17:18 PM PDT by BipolarBob (If people make you sick, maybe you should try cooking them longer.)
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To: Pocketdoor

I can see Jabba in there, I can also see what looks to be several very distorted faces of women in heavy makeup. Kid of like looking at clouds, or some kind of Martian Rorschach test.


18 posted on 06/29/2025 6:20:29 PM PDT by Antihero101607
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To: BipolarBob

Nobody goes there since it lost its atmosphere.


19 posted on 06/29/2025 6:27:31 PM PDT by HandyDandy (“Borders, language and culture.” Michael Savage)
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To: BipolarBob

My father told me that he read all of the John Carter books when he was a kid back in the dark ages.


20 posted on 06/29/2025 6:32:26 PM PDT by GaltAdonis
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