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Astronomy Picture of the Day - The Spiral North Pole of Mars
NASA ^ | 6 Jul, 2025 | Image Credit: ESA/DLR/FU Berlin; NASA MGS MOLA Science Team

Posted on 07/06/2025 11:44:43 AM PDT by MtnClimber

Explanation: Why is there a spiral around the North Pole of Mars? Each winter this pole develops a new outer layer about one meter thick composed of carbon dioxide frozen out of the thin Martian atmosphere. This fresh layer is deposited on a water-ice layer that exists year round. Strong winds blow down from above the cap's center and swirl due to the spin of the red planet -- contributing to Planum Boreum's spiral structure. The featured image is a perspective mosaic generated in 2017 from numerous images taken by ESA's Mars Express and elevations extracted from the laser altimeter aboard NASA's Mars Global Surveyor mission.


TOPICS: Astronomy; Astronomy Picture of the Day; Science
KEYWORDS: apod; nasa
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 07/06/2025 11:44:43 AM PDT by MtnClimber
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To: MtnClimber

2 posted on 07/06/2025 11:45:13 AM 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 07/06/2025 11:46:12 AM 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
New Finding - The Martian North Pole is mostly baked goods.
4 posted on 07/06/2025 11:48:11 AM PDT by DannyTN
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To: MtnClimber

Similar to what the trade winds would do on earth, I guess, if the surface never changed except for wind erosion.


5 posted on 07/06/2025 12:03:29 PM PDT by Telepathic Intruder
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To: MtnClimber

Hey, that’s pretty cool. But sorry Elon, still don’t want to live there.


6 posted on 07/06/2025 12:07:58 PM PDT by Bullish (My tagline ran off with another man, but it's ok---- I wasn't married to it.)
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To: MtnClimber

Looks like water caused that swirling ... but then ...


7 posted on 07/06/2025 12:09:24 PM PDT by SkyDancer ( ~ Am Yisrael Chai ~)
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To: SkyDancer

It was those darned Martian SUVs and coal mines that melted everything…


8 posted on 07/06/2025 12:21:25 PM PDT by rfp1234 (E Porcibus Unum)
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To: SkyDancer

I wonder what the distance is across the photo.


9 posted on 07/06/2025 12:36:14 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: DannyTN

Cinnabon? Mmmmmmmmm…….😛


10 posted on 07/06/2025 3:00:55 PM PDT by telescope115 (I NEED MY SPACE!!! 🔭)
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To: Telepathic Intruder

One thing that is curious is that Mars’ North Pole appears to be terraced. It would be cool to know what forces caused that.


11 posted on 07/06/2025 3:03:45 PM PDT by telescope115 (I NEED MY SPACE!!! 🔭)
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To: telescope115

Are those terraces or canyons? Hard to tell from one angle only. Mars has been almost geologically dead since the early solar system. Almost the only thing that shapes the surface anymore is wind.


12 posted on 07/06/2025 4:10:43 PM PDT by Telepathic Intruder
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To: Telepathic Intruder
Very true.

One thing’s for certain- Percival Lowell was wrong about the canals.

13 posted on 07/06/2025 5:18:43 PM PDT by telescope115 (I NEED MY SPACE!!! 🔭)
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