A Hole in Mars (APOD 28 May 2007)

[JohnD]

Is it a hole?

Have a look at this object on Google Earth - the Waw an Namus in Libya at 24 degrees 58' 50.59" N 17Deg 44' 42.63" E

Then look at the photos of it from ground level - it looks nothing like that, just an oasis in a depression.

Why does it look like that from space?

John

[Fabio Knopf]

First of all, sorry about any mispelling. I just don´t speak english.

Well, if it´s not a cave, then it is something we´ve never seen before.
The HiRISE camera is *really* sensitive, and it could get nothing from the hole.

Probably, they´re skylights, like this one: http://www.oregonl5.org/lavatube/images/skylite1.jpg

What is really amazing is the different thermal behavior betwen night and day, as you can check here: http://planetary.org/image/caves.jpg

Any geologists here? Any ideas?

[kbowersjr]

The "black spot" looks like a tar pit! If there is oil on Mars, then it is certain that oil is an accululation product from planet formation and is not the product of plant decay.

The implications for Man are immense. Our resources of oil are much larger than thought. (There could also be oil on the Moon).

Ken Bowers
Phoenix

[ta152h0]

what is the mechanical/chemical/raw products reaction required to produce crude oil ?

[craterchains]

Some think that our crude oil was formed by meteor strikes, big ones.

Also that past president Harry Trueman stated that with atomic weapons any industry on the surface of the planet could now be destroyed. Underground is the only safe place now.

[Dr. Skeptic]

what is the mechanical/chemical/raw products reaction required to produce crude oil ?

Some say oil is from metamorphosed organisms of early Earth, others suggest hydrocarbons embedded in the Sun's accretion disk created oil early in Earths formation. Neither theory has been proved.

[iamlucky13]

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?

ESA's Mars Express has a long wavelength radar designed to map subsurface water. I'm not sure the resolution, but I gather it was on the order of a km or so, in which case it might not be able to spot these caves.

The HiRISE camera on MRO also has near infrared capabilities. Comparing night and day thermal images might be very telling, but I don't think its range includes thermal IR.

what is the mechanical/chemical/raw products reaction required to produce crude oil ?

You need carbon, hydrogen, and energy. All of these are available on Mars, but the general conditions are against it. On earth these were probably combined via plant matter, and then protected underground via sublimation. I think the biggest problem is hydrocarbons tend to break down in the Martian environment, so any big pool of oil should gradually oxidize into CO2 and water vapor. The oil theory raises a really glaring question of how it can exist at the surface and why it would only be seen in these spots.


I think the skylights makes the most sense. If it were a normal hole, you should be able to see a sunlight cave wall for some distance based on the sun angle...unless the sun angle just happened to match the wall angle. Instead, that appears to be very shallow. If it's opens up underneath though, the wall is shadowed by the roof. However, these holes are big (~200 meters for the APOD?). That means a huge lava tube, but perhaps the size limits of such a structure are much different in 0.38 G?

Have a look at this object on Google Earth - the Waw an Namus in Libya at 24 degrees 58' 50.59" N 17Deg 44' 42.63" E

I think this link should show that properly. That feature is about 10 miles across. It's actually an extinct volcano filled with dark material...but not as black as what we see in the APOD.

[iamlucky13]

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

Underground would have more stable temperatures and also a higher likelihood of liquid water. Also it would protect any possible organisms from the intense radiation that reaches the martian surface due to Mars' weak magnetic field.

[orin stepanek]

While I don't say for certain that the black spot is an oil lake I wouldn't be quite so quick to rule it out. Why should oil break down into water vapor and CO2 in mars' atmosphere. I would think the cold conditions there would more than likely preserve mater than for it to deteriorate. And what other spots would you expect to see oil on the surface? While the spot may indeed be a hole; I still think it looks more like a pool. I think some day an expedition to Mars may unlock some startling discoveries.
Orin

[BMAONE23]

Maybe the ESA could look into the area with Mars Express ground penetrating radar on its next pass over the area. It should be able to see a hollow point.

[JohnD]

Have a look at this object on Google Earth - the Waw an Namus in Libya at 24 degrees 58' 50.59" N 17Deg 44' 42.63" E

I think this link should show that properly. That feature is about 10 miles across. It's actually an extinct volcano filled with dark material...but not as black as what we see in the APOD.

That's the place. But that is to Google Maps. On Google Earth, there are links to photos taken from ground level, that show - desert. With oases. No dark material.
If the Waw an Namus on Earth shows up like that from space, what effect causes it, and would it happen on Mars too? Ie - nothing so dark on the ground, just - desert.
JOhn

[BMAONE23]

http://www.fjexpeditions.com/frameset/waunamus.htm

a good link to the same wau namus region with images from the ground. It could be that the particular image strip was exposed for the lightness of the surrounding bright sand which caused the darker volcanic material to appear darker than it is

[pjsuther]

Why would it have to be oil? Why not some other liquid that could sustain a colloidal dispersion at the typical martian temperature ranges? Opacity is a common feature of these solutions.

[Doum]

If it was oil (Wich i dunno how it could be create on mars?) , the UV from the sun and the almost absent atmosphere from mars to stop it would of broken all these chain of carbon from the billion of years of UV bombardment from the sun on the mars surface. And guess what, it would of broke it into H2O and CO2. All that from UV ray. In case some of you dont know, many organic compound are destroy by UV. Even in water treatment process there is a UV step to eliminated these carbon chain. So for that reason i doubt this round dark stuff is oil. Note that i said i doubt it wich mean i keep an open minded for any other possibility for that strange feature. I realy hope its a volcano cavern cause it might open mars planet to humand kind more quickly.

[Javachip]

At first glance, I thought the black spot was a silhouette of one of Mars' small moons, orbiting below the Mars Orbiter. After excluding that possibility, I thought it must be an artifact or a deliberate fake. Since it doesn't appear to be either of those things, the mystery just gets deeper.

If it is a sinkhole or a chimney or a cavern roof that collapsed, it must be a very large cavern underneath, to explain the total blackness within the hole. If it is a large void space with a thin roof above it, the whole terrain should be very unstable, and there should be many more holes of various shapes and sizes in the vicinity.

Are either of the surface rovers still operating? If so, and if they are within roving range of this feature, it would make a fascinating excursion.

[BMAONE23]

I've looked at the Hi-res image of the area and I acn count at least 10 such holes in the area. Most are only about 15 - 20 meters accross

[Wadsworth]

http://www.fjexpeditions.com/frameset/waunamus.htm

a good link to the same wau namus region with images from the ground. It could be that the particular image strip was exposed for the lightness of the surrounding bright sand which caused the darker volcanic material to appear darker than it is

Exactly, the surrounding terain is extreamly bright and reflective, washing out the interior hole / pool.

For those who think it is a hole of some sort how do you explain the protrutions shown here just shy of twelve o'clock and again blown up here?

This would be hard to form as an overhanging cliff..

[orin stepanek]

http://antwrp.gsfc.nasa.gov/apod/ap070528.html
I thought it would be easier to see what the subject was by posting the link.
Orin

[JohnD]

Thank you, BMAONE!
The pics in that link are much better than those on Google Earth and clearly explain the blackness of the satellite image.

Now, if a terrestrial black sand area can produce a similarly black on black image, why postulate a hole, or even, for goodness sake, oil? There is lots and lots of sand on Mars, and some of it is different colours - see the Spirit/Opportunity pics.
Volcanic black sand is found on Earth also at Tahiti, Hawaii, Iceland and even California - just Google for "black sand". All coastal sites, but Waw an Namus is a long way from the sea.

John

[iamlucky13]

For those who think it is a hole of some sort how do you explain the protrutions shown here just shy of twelve o'clock and again blown up here?

This would be hard to form as an overhanging cliff..

Good question. My best guess would be a concave wall face...so the top is lit, the bottom is lit, but the middle isn't.

Still, this picture is really puzzling. It just doesn't look right. Hopefully MRO will have a chance to take follow up pictures of this region from a different angle and with different lighting. That could tell a lot about what is there. For one, the zoom belies a useful sense of depth.

At my first glance I swore it was some kind of weird artifact, but the HiRISE team doesn't seem to think so, and they know the camera better than anyone. I think deeply shadowed or liquid makes more sense than dark solid material, because with the dynamic environment on Mars, there shouldn't a perferctly homogenous surface. The Waw an Namus is not nearly as evenly colored. Hydrocarbons would be almost as big of a surprise, so I can only think a cave or sinkhole or a bad photoshop.

[jimsaruff]

Wadsworth, would you, please, zoom in between 3 o'clock and 4 o'clock for us.

It seems to me that you have really 'focused' the discussion with your observations of 'protrusions'.

Thanks.

[Wadsworth]

Ok, here is the section between three and four. A small "protrusion" can be seen here, but under closer scrutiny it looks like a landslide has fallen through a 'wash gully' of sorts to cause the protrusion. Blown up.. This couldn't be the case if it were a hole, but is very possible if this were say a creator full of a liquid or darker solid etc.
Diagram

Thoughts?

[orin stepanek]

The area above the hole looks lighter in color. When I magnified 400% it looks almost like venting is causing the discoloration. May it be a cauldron of some sort?
Orin

[pjsuther]

One other thing: how steep is the incline at the flank of the volcano where this thing is located? The brighter rim above the black seems to be the same height all way round. If there was an incline here and the black was liquid, I would think we would see a narrowing of the rim on the 'downslope' side.

[13 Rabbit]

I've looked at the Hi-res image of the area and I acn count at least 10 such holes in the area. Most are only about 15 - 20 meters accross

Where might one find this image?