APOD: A Dark Dune Field in Proctor Crater (2010 Nov 22)

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APOD: A Dark Dune Field in Proctor Crater (2010 Nov 22)

Post by APOD Robot » Mon Nov 22, 2010 5:06 am

Image A Dark Dune Field in Proctor Crater on Mars

Explanation: Was this image taken with a telescope or a microscope? Perhaps this clue will help: if the dark forms were bacteria, they would each span over football field across. What is actually being seen are large sand dunes on the floor of Proctor Crater on Mars. The above picture was taken by HiRISE camera on board the Mars Reconnaissance Orbiter (MRO), a robot spacecraft currently in orbit around Mars. The dark rippled dunes likely formed more recently than the lighter rock forms they appear to cover, and are thought to slowly shift in response to pervasive winds. The dunes arise from a complex relationship between the sandy surface and high winds on Mars. Similar dunes were first seen in Proctor Crater by Mariner 9 more than 35 years ago.

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Re: APOD: A Dark Dune Field in Proctor Crater... (2010 Nov 2

Post by Sam » Mon Nov 22, 2010 5:20 am

bacteria.jpg
images.jpg
images.jpg (12.63 KiB) Viewed 9659 times
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Re: APOD: A Dark Dune Field in Proctor Crater (2010 Nov 22)

Post by bystander » Mon Nov 22, 2010 5:28 am

Know the quiet place within your heart and touch the rainbow of possibility; be
alive to the gentle breeze of communication, and please stop being such a jerk.
— Garrison Keillor

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Re: APOD: A Dark Dune Field in Proctor Crater... (2010 Nov 2

Post by flick » Mon Nov 22, 2010 5:32 am

It would be nice to have the context -- a wider view of the crater mentioned so we could see the dune fields as part of a larger structures. Following the links provided, I can't seem to get the bigger picture. (Maybe it's just me.)

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Re: APOD: A Dark Dune Field in Proctor Crater... (2010 Nov 2

Post by bystander » Mon Nov 22, 2010 5:34 am

flick wrote:It would be nice to have the context -- a wider view of the crater mentioned so we could see the dune fields as part of a larger structures. Following the links provided, I can't seem to get the bigger picture. (Maybe it's just me.)
Know the quiet place within your heart and touch the rainbow of possibility; be
alive to the gentle breeze of communication, and please stop being such a jerk.
— Garrison Keillor

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Re: APOD: A Dark Dune Field in Proctor Crater (2010 Nov 22)

Post by petsie » Mon Nov 22, 2010 10:44 am

the first few images on http://www.mikroskopie-forum.de/index.php?topic=3038.0 look a bit similar.

mitcoyote

Re: APOD: A Dark Dune Field in Proctor Crater (2010 Nov 22)

Post by mitcoyote » Mon Nov 22, 2010 10:55 am

Looks a lot like E. coli, but lots of bacilli look like this.

JH

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Re: APOD: A Dark Dune Field in Proctor Crater (2010 Nov 22)

Post by owlice » Mon Nov 22, 2010 12:22 pm

I love this image, but then, I love the HiRISE images in general. I find them very beautiful and am thrilled to see one as an APOD.
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Re: APOD: A Dark Dune Field in Proctor Crater (2010 Nov 22)

Post by arcosine » Mon Nov 22, 2010 1:28 pm

What is seen in the photo is the same stuff Opportunity had been driving through for the past years. The dark depressed areas are full of the "blueberries" The light rocks are broken pieces of the crumbly eroded sedimentary rocks. What we are looking at are large eroded sand dunes that were formed billions of years ago when the climate was different, before the wet era.

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Re: APOD: A Dark Dune Field in Proctor Crater (2010 Nov 22)

Post by orin stepanek » Mon Nov 22, 2010 1:31 pm

When the picture is enlarged; the rippling on the black dunes can be seen more clearly! Why are they so black though? The video link shows views of many dunes on Mars.
Click to play embedded YouTube video.
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Noachis Way

Post by neufer » Mon Nov 22, 2010 1:35 pm

http://en.wikipedia.org/wiki/Noachis_quadrangle wrote:
<<The Noachis quadrangle is one of a series of 30 quadrangle maps of Mars used by the United States Geological Survey (USGS) Astrogeology Research Program.

The Noachis quadrangle covers the area from 300° to 360° west longitude and 30° to 65° south latitude on Mars. It lies between the two giant impact basins on Mars: Argyre and Hellas. Noachis is so densely covered with craters that it is deemed among the oldest landforms on Mars. When a location on Mars is as old, it is said to be Noachian in age.

In many places on Mars, buried craters are being exposed. That is a crater formed long ago, then was buried, and is now being exposed. This takes place in Noachis, as Noachis is plenty old enough for this process to take place.

The first piece of human technology to land on Mars landed (crashed) in the Noachis quadrangle. The Soviet's Mars 2 crashed at 44.2° S and 313.2° W. It weighed about one ton. The automated craft attempted to land in a giant dust storm. To make conditions even worse, this area also has many dust devils.>>
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anon

Re: APOD: A Dark Dune Field in Proctor Crater (2010 Nov 22)

Post by anon » Mon Nov 22, 2010 1:40 pm

Look more like sinkholes to me.

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Re: APOD: A Dark Dune Field in Proctor Crater (2010 Nov 22)

Post by owlice » Mon Nov 22, 2010 2:22 pm

Oh, neufer! Are you trying to make me explode? So many HiRISE images at one time just might do it!
A closed mouth gathers no foot.

CosmosWolf

Re: APOD: A Dark Dune Field in Proctor Crater (2010 Nov 22)

Post by CosmosWolf » Mon Nov 22, 2010 2:34 pm

:oops: It kinda reminds me of fecies (sorry if I spelled it wrong) :oops:

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Re: APOD: A Dark Dune Field in Proctor Crater (2010 Nov 22)

Post by neufer » Mon Nov 22, 2010 2:40 pm

owlice wrote:
Oh, neufer! Are you trying to make me explode?
So many HiRISE images at one time just might do it!
To the Juicing Room, STAT :!:
Art Neuendorffer

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Re: APOD: A Dark Dune Field in Proctor Crater (2010 Nov 22)

Post by UseUrHeadFred » Mon Nov 22, 2010 2:57 pm

I'm hotlinking this from the University of South Carolina School of Medicine, and thanks to them and the NIH for this image.
Pseudomonas aeruginosa - the cause of "hot tub folliculitis" and urinary tract infections, among other things.

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Blue Black Barsoom Bar Stool?

Post by neufer » Mon Nov 22, 2010 3:02 pm

CosmosWolf wrote:
:oops: It kinda reminds me of fecies (sorry if I spelled it wrong) :oops:
[c]Feces from a different species?
(Blue Black Barsoom Bar Stool?)[/c]
http://en.wikipedia.org/wiki/Plant_Men_of_Barsoom wrote:
<<The Plant Men are a fictitious species existing in the Valley Dor region on the planet Barsoom (i.e. Mars) in the John Carter series of books by Edgar Rice Burroughs. Ten to twelve feet tall, with short arms resembling an elephant's trunk, they are hairless except for their head and blue in color except for a broad band of white encircling a single protruding eye; the pupil and iris of which are dead white like the eyeball. The body, legs and feet are humanoid, but monstrously proportioned, the feet being fully one meter long, and very flat and broad. They possess a massive tail about six feet long, round where it meets the body and tapering to a flat, thin blade at the end, carried at right angles to the ground. The head, except for the blank face, is covered by a tangle of jet-black hair eight to ten inches in length with each hair the thickness of a large earthworm. There is no mouth in the face, and the nose is merely a ragged, gaping, inflamed circular hole in the center of the face, similar to an open wound. The Plant Men have a mouth in the palm of each hand, with which they feed on tender vegetation which they shear with their razor-sharp talons, or the blood of their victims. After "the defiling blood of life has been drawn" from a human by the Plant Men, the flesh may be eaten by the Holy Therns, another Barsoomian race.>>
UseUrHeadFred wrote:
Pseudomonas aeruginosa - the cause of "hot tub folliculitis" and urinary tract infections, among other things.
Perhaps, Proctor Crater was a giant Plant Men hot tub.
Art Neuendorffer

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Re: APOD: A Dark Dune Field in Proctor Crater (2010 Nov 22)

Post by Prank Zabba » Mon Nov 22, 2010 3:16 pm

http://www.boingboing.net/vinylgrooves.png

An optics researcher at the University of Rochester used an electron microscope to look at the grooves on records. This is a single groove magnified to 1000x.

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Re: APOD: A Dark Dune Field in Proctor Crater (2010 Nov 22)

Post by maristoddard » Mon Nov 22, 2010 3:55 pm

Wikipedia - http://en.wikipedia.org/wiki/Cilium
"cilia projecting from respiratory epithelium in the lungs"
Image


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Re: APOD: A Dark Dune Field in Proctor Crater (2010 Nov 22)

Post by tekic545 » Mon Nov 22, 2010 4:37 pm

The large, dark "bacterial" dunes appear to be superimposed on a complex field of much smaller dunes, formed in turn on some nastily complex system of bedrock ridges. Any information as to the difference in material composition between the big dunes and the surrounding dune-like terrain? Or is this more a function of lighting?

Bob

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Re: APOD: A Dark Dune Field in Proctor Crater (2010 Nov 22)

Post by neufer » Mon Nov 22, 2010 5:21 pm

tekic545 wrote:
The large, dark "bacterial" dunes appear to be superimposed on a complex field of much smaller dunes, formed in turn on some nastily complex system of bedrock ridges. Any information as to the difference in material composition between the big dunes and the surrounding dune-like terrain? Or is this more a function of lighting?
[img3="Don't confuse "dunes" with "sand ripples""]http://images.travelpod.com/users/imapi ... ipples.jpg[/img3]
Art Neuendorffer

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Re: APOD: A Dark Dune Field in Proctor Crater (2010 Nov 22)

Post by tekic545 » Mon Nov 22, 2010 5:36 pm

Ah, I hadn't realized we are looking at sand-ripple scale. But still, we appear to have very dark sand on top of light (rippled) sand. Is there a material difference, and if so, what process keeps the light and dark materials separate?

Bob

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Re: APOD: A Dark Dune Field in Proctor Crater (2010 Nov 22)

Post by DCStone » Mon Nov 22, 2010 6:47 pm

neufer wrote:Don't confuse "dunes" with "sand ripples" http://images.travelpod.com/users/imapi ... ipples.jpg
Ripples, you said? http://www.chem.utoronto.ca/~dstone/images/ripples.gif
Image

Or would you prefer rockets? http://www.chem.utoronto.ca/~dstone/images/biorckt.gif
Image

(I miss doing SEM!)


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