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Astronomy Picture of the Day - Striped Sand Dunes on Mars
APOD.NASA.gov ^
| 6 Jan, 2021
| Image Credit: HiRISE, MRO, LPL (U. Arizona), NASA; Processing: Włodek Głażewski; Text: Alex R. Howe
Posted on 01/06/2021 3:30:58 PM PST by MtnClimber
Explanation: Why are these sand dunes on Mars striped? No one is sure. The featured image shows striped dunes in Kunowsky Crater on Mars, photographed recently with the Mars Reconnaissance Orbiter’s HiRISE Camera. Many Martian dunes are known to be covered unevenly with carbon dioxide (dry ice) frost, creating patterns of light and dark areas. Carbon dioxide doesn’t melt, but sublimates, turning directly into a gas. Carbon dioxide is also a greenhouse material even as a solid, so it can trap heat under the ice and sublimate from the bottom up, causing geyser-like eruptions. During Martian spring, these eruptions can cause a pattern of dark defrosting spots, where the darker sand is exposed. The featured image, though, was taken during Martian autumn, when the weather is getting colder – making these stripes particularly puzzling. One hypothesis is that they are caused by cracks in the ice that form from weaker eruptions or thermal stress as part of the day-night cycle, but research continues. Watching these dunes and others through more Martian seasons may give us more clues to solve this mystery.
TOPICS: Astronomy; Astronomy Picture of the Day; Science
KEYWORDS: apod; astronomy; kunowskycrater; mars; nasa; science
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For more detail go to the link and click on the image for a high definition image. You can then zoom by moving the magnifying glass over an area and then clicking. The side bars will move the zoomed area over the photograph.
To: MtnClimber
2
posted on
01/06/2021 3:31:20 PM PST
by
MtnClimber
(For photos of Colorado scenery and wildlife, click on my screen name for my FR home page.)
To: 21stCenturion; 21twelve; 4everontheRight; abb; AFB-XYZ; America_Right; Art in Idaho; AZ .44 MAG; ...
Pinging the APOD list.
🪐 🌟 🌌
3
posted on
01/06/2021 3:31:49 PM PST
by
MtnClimber
(For photos of Colorado scenery and wildlife, click on my screen name for my FR home page.)
To: MtnClimber
That’s not striping. That’s chocolate frosting. Mars is a giant Lindt Truffleball.
4
posted on
01/06/2021 3:33:20 PM PST
by
Seruzawa
(TANSTAAFL!)
To: Seruzawa
I have to go with Seruzawa on this one.
5
posted on
01/06/2021 3:36:15 PM PST
by
blueunicorn6
("A crack shot and a good dancer”)
To: blueunicorn6
6
posted on
01/06/2021 3:52:15 PM PST
by
null and void
(When the press doesn’t report something, it’s because the narrative would reflect badly on the Left)
To: null and void
Nope.
I think Seruzawa nailed it.
7
posted on
01/06/2021 4:21:04 PM PST
by
blueunicorn6
("A crack shot and a good dancer”)
To: MtnClimber
8
posted on
01/06/2021 5:31:19 PM PST
by
ETL
(REAL Russia collusion! DEMOCRAT-Russia collusion!! CHINA-Russia collusion! Click ETL...)
To: MtnClimber
Looks like here, Yuma Proving Grounds, Mars on Earth👍
9
posted on
01/06/2021 5:32:52 PM PST
by
gbs
To: MtnClimber
10
posted on
01/06/2021 5:35:02 PM PST
by
ETL
(REAL Russia collusion! DEMOCRAT-Russia collusion!! CHINA-Russia collusion! Click ETL...)
To: ETL
It is a sad day when I can’t find a cheeseburger in the APOD photo.
11
posted on
01/06/2021 5:44:30 PM PST
by
MtnClimber
(For photos of Colorado scenery and wildlife, click on my screen name for my FR home page.)
To: MtnClimber
Looks like Chinese calligraphy.......................
12
posted on
01/07/2021 5:15:21 AM PST
by
Red Badger
(TREASON is the REASON for the SLEAZIN'.................................)
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