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A Hole in Mars (APOD 28 May 2007)

Posted: Mon May 28, 2007 4:35 am
by craterchains
"Quite possibly, the spots are entrances to deep underground caves capable of protecting Martian life, where it to exist."

Now that is about as wishy washy as one can get and still not say anything of value. Why say it at all I wonder?

Philosophical curiousity

Posted: Mon May 28, 2007 4:36 am
by RyGardner
I have a philosphical curiousity about life on mars. In the description for the Hole in Mars there was mention of the caves being a potential spot for the martians, "[were] they to exist", to hide. My curiosity is multi-layered... If there were in fact martians, why would they be in the caves? Heat, surface weather, ect? Could they be hiding from us, or another race? And then I guess my deeper curiousity is that might we, living arrogantly on the surface, be foolish or naive in doing so?

Any thoughts?

Ryan

- amendment -

Posted: Mon May 28, 2007 4:38 am
by RyGardner
I realized that I used the word "hide" which wasn't what the description used, and which was an initial presumption on my part...

Thanks,

Ryan

Posted: Mon May 28, 2007 4:44 am
by ReallyFUBAR
the "hole" looks fake. and bad fake like i could MS Paint a better one. bleh. if it was true youd like to see more displacement. or some thing, it looks like I did a drunken freeform crop.

Any longer exposures?

Posted: Mon May 28, 2007 4:47 am
by eanwhite
Has anyone tried to collect more light with a longer exposure? The image posted is exposed for the surface... Is there absolutely no light in the holes or is it only relative to the light on the surface?

Couldn't we put a light in one of these holes in three years? If we really want to?

Ean

Posted: Mon May 28, 2007 5:01 am
by craterchains
Taken from one of the links.

"We'll never know for sure without visiting it, but I expect that Cushing and his coauthors and the HiRISE team will be crunching the numbers on the illumination conditions and the sensitivity of the camera to put a lower limit on how deep that cave must be for HiRISE to be able to see nothing at all inside it."

I bet they will.

The holes appear clearly on MARS maps

Posted: Mon May 28, 2007 5:49 am
by gadieid
I have the National Geographic map of Mars from Feb 2001. The hole appears clearly there. Of course I never noted it before, it is there and resamble the strucutre seen in this photo. Try to look for the map in te NG site.

Posted: Mon May 28, 2007 6:34 am
by sagian
Does anyone else see the quasi-elliptical depression surrounding this hole? Or is it a rise? Or perhaps it's just a ridge?

It's between about 3 and 6 hole-diameters out, all the way around.

Mars MAP

Posted: Mon May 28, 2007 7:42 am
by gadieid
Look for Mar Map, You can zoom in and see the exact hole. It is in the left side of the map...
http://www.ngmapstore.com/shopping/prod ... ductID=171

grammar etc.

Posted: Mon May 28, 2007 8:01 am
by menelaos42
I just thought it interesting that the NASA-backed APOD site would post such a glaring grammatical error. "...where it to exist." This should read "...were it to exist." I apologize in advance for any criticism this may draw as pertains to nitpicking and such, but it surprised me.

Be easy.

Posted: Mon May 28, 2007 8:45 am
by rigelan
Yeah, it looks like a camera glitch, but its too huge at that resolution to be so. It kinda excites me to have shafts this deep.

If they were on earth, they would probably be filled with water, and we would fish on the natural springs they exhibit.

Posted: Mon May 28, 2007 11:10 am
by l3p3r
Two events this year that have got me all excited! The hexagon on Saturn and this!

I have no doubt that the feature is real - these holes pop up in many photos so they are not errors in the photograph.

What troubles me is that there appears to be no resolution of the interior at all, despite the fact that sunlight is obviously striking the ground at quite a shallow angle to the horizon (as we can see from the craters.) Yet wouldn't perspective render at least part of the wall of the hole visible? Perhaps the walls slant outwards as the hole gets deeper - or maybe we are seeing something as exotic as a hole in a shell rather than a 'tube'.

Intriguing. The sharpness and definition of the edge is surprising!

But I agree with you craterchains, the text contains a totally unnecessary piece of speculation.

Posted: Mon May 28, 2007 12:37 pm
by jokergirl
Am I the only one who is reminded of the terraforming potholes in K.S.Robinson's Red Mars by that picture?
I'll have to pick up the book again when I come home to check the exact description of their holes.

I wonder about the smear of white above the hole in the image; is it smoke/clouds, deposits or something else?

;)

Posted: Mon May 28, 2007 12:39 pm
by JohnD
It's not a fake - see the HiRise version. Look at it in fullscreen to see what detail of the edges is possible.

http://hiroc.lpl.arizona.edu/images/200 ... _cut_b.jpg
And see the full photo and discussion,
http://hiroc.lpl.arizona.edu//images/PS ... 03647_1745
where they comment that HiRise can "see details in almost any shadow on Mars, but not here" so that the depression beneath must be deep and have very steep or overhanging sides to make the inside so dark.
John

Posted: Mon May 28, 2007 1:14 pm
by DaleA
I see this not as a lack of light in a hole but as a very dark filling of a hole. My evidence is in the in the HiRise version at http://hiroc.lpl.arizona.edu/images/200 ... _cut_b.jpg Notice at about the 4 O'clock position in the original photo there appears to be a collapse of the wall that spreads out on a black "floor". It appears to me that it is a hole with a light absorbing substance covering a flat floor. Another indication is the sharpness of the edges even where there is no direct illumination (9 O'Clock). The sharpness indicates a discontinuity of the edge yet we have several intrusions on the edge (4 O'clock and 11 O'clock as examples).

Posted: Mon May 28, 2007 1:51 pm
by orin stepanek
Like a black liquid lake? Maybe oil? :D
Orin

Posted: Mon May 28, 2007 2:08 pm
by Diamonddavej
They say the holes are collapsed lava tubes (couple of hundred meters wide and deep).

I agree with this idea. They look fresh, no doubt the holes are quickly in-filled by wind blown dust. Some craters near the holes are not craters, they are in filled holes; they have odd looking rims. How many "craters" are not craters?

Another possibility, some of them maybe solutional collapse structures - that a layer of evaporatic materials (gypsum/salt) dissolve to form a caves. This is an interesting idea as it would imply current groundwater flow on mars.

The final crazy idea, they are alien weapon fire that poked holes in mars.

Here is a lava tube's sky light in Utah...

Image

Posted: Mon May 28, 2007 2:58 pm
by liu xingyu
I don't doubt the real of the picture when I saw it on fist sight.What puzzle me was in what way can such a perfect hole make?
The underground water's flow maybe can make such hole.But I got another suspection: the falling stone hit it out . of course,in our moon such a beautiful hole can not be make.-----just image: there is a poll dry up,just mug left ,under the mug is the rock and sand,between the mug and sand is water flowing. when the mug is dry to just good,what the crater will look like when a stone shot into the mug?can a hole like this be make?
So ,if the suspection above is right ,then there will be plenty of water on mars.

Hole in Mars?

Posted: Mon May 28, 2007 4:38 pm
by pjsuther
I think DaleA has got it, especially with the blackness appearing to encroach on the rim at about "11:30" on the enlarged view from the planetary.org blog. Could not a liquid body also display the same thermal properties - similar to surrounding temps during the day and then warmer than the surrounding material at night? I recall the joys of night time bathing in the Pacific from that very quality...

A Hole in Mars

Posted: Mon May 28, 2007 4:54 pm
by smitty
Can anyone please refresh my memory regarding current Mars orbiters: does any of them have a radar-based terrain mapping capability? If so, could it be programmed to plumb the depths of one or more of the holes discovered on Mars?

add fuel to the speculation fire

Posted: Mon May 28, 2007 5:11 pm
by ta152h0
I thought the boulder ( ? ) on this object also seemed out of place

http://near.jhuapl.edu/iod/20000503/index.html

I noticed that when published and my friends though it was just a rock. Looks too square and we all know nature abhors straight lines. :P Pass some more beer around :D

Posted: Mon May 28, 2007 6:34 pm
by Wadsworth
My first impression was that of a lake like structure as DaleA mentioned, not an impossibly deep cave..
Where (or were) do these titles, or overzealous assumptions, come from?
It seems painfully obvious that it isn't an empty cavern.

A Hole in Mars

Posted: Mon May 28, 2007 6:41 pm
by rmmarvos
I log on to APOD daily and enjoy the photos and descriptions posted. While some are quibbling about a probable typo (were). As a former caver, you have committed one of my favorite redundancies -- "underground cave." Is there any other kind of cave? Otherwise, keep up the good work.

Posted: Mon May 28, 2007 9:02 pm
by Doum
If it is strong enough deep below then perhaps it is possible to close the opening, fill it with air and "Voila" a Mars space base is build. Vast and yet (May be ) relatively cheap to build considering the possible size of it. I know its speculation but i enjoy it. At least there would be life there then. :)

Posted: Mon May 28, 2007 10:09 pm
by BMAONE23
Doum,
You've hit uopn a means of establishing our presence there. Covering this "Hole" (and others) would be easily done with geodesic dome technology. It could then be pressureized and be a good base. It could even be used for growing food crops.