Light Deposits, Water Flowing on Mars (APOD 12 Dec 2006)

Confused · Post by **Confused** » Tue Dec 12, 2006 10:09 am

This is for the APOD for 2006 December 12, but evidently there is not enough room for the title and date in the subject field.

I hope it is appropriate for me to start this thread.

My comment is that I am interested in the skeptics. What are the chances that it was not water? What other theories are there?

If it was water that caused the deposits, then that surely is exciting, but are scientists jumping to conclusions?

Nereid · Post by **Nereid** » Tue Dec 12, 2006 10:20 am

I edited the title; what you wrote is quite OK for a thread starter.

fatcitymax · Post by **fatcitymax** » Tue Dec 12, 2006 11:47 am

The picture shows a rockfall uncovering lighter colored soil, not evidence of water flow. That is clearly a very steep incline.

Confused · Post by **Confused** » Tue Dec 12, 2006 12:10 pm

Nereid wrote:I edited the title; what you wrote is quite OK for a thread starter.

Good.

Confused · Post by **Confused** » Tue Dec 12, 2006 12:15 pm

fatcitymax wrote:The picture shows a rockfall uncovering lighter colored soil, not evidence of water flow. That is clearly a very steep incline.

That sure sounds like a reasonable potential explanation. I am not a geologist or anything like that but the media sure likes to emphasize the dramatic. If NASA says it is likely evidence of water then I will trust that it is reasonable to suspect it probably is but I hope people don't exagerate what NASA says.

fatcitymax · Post by **fatcitymax** » Tue Dec 12, 2006 1:16 pm

NASA is anxious to find reasons for a manned mission to Mars.

beatsleepless · Post by **beatsleepless** » Tue Dec 12, 2006 1:36 pm

http://www.slate.com/id/2155117

Water or not, there still appear to be significant barriers to human existence on Mars.

It seems like the capacity to dream was much stronger when we knew less. As more of our little piece of the universe is exposed, bit by bit, we seem a little more alone.

Confused · Post by **Confused** » Tue Dec 12, 2006 1:36 pm

{I am replying to fatcitymax.}

Why is water a reason to go to Mars? Is it that water makes it more likely that life exists? I think the (potential) discovery of life is a good reason to send unmanned missions until we have discovered enough that manned missions are productive.

The subject of water on Mars I thought was also important because it makes Mars more practical for manned missions, but for that, they sure better be right about the water.

If NASA is exagerating the value and pragmatism of manned misions to Mars then it is even more important to listen to the skeptics. You seem to agree.

fatcitymax · Post by **fatcitymax** » Tue Dec 12, 2006 2:01 pm

See

http://antwrp.gsfc.nasa.gov/apod/ap060406.html

for more 'evidence' of water.

BMAONE23 · Post by **BMAONE23** » Tue Dec 12, 2006 2:11 pm

While it certainly could be a rock slide which has uncovered lighter soil much like the rover wheels have, It could also possibly be water that has flowed down slope then frozen into white ice.

beatsleepless · Post by **beatsleepless** » Tue Dec 12, 2006 2:32 pm

fatcitymax wrote:See
http://antwrp.gsfc.nasa.gov/apod/ap060406.html
for more 'evidence' of Mars cocaine.

Fixed your post.

Just kidding, of course.

BMAONE23 wrote:...It could also possibly be water that has flowed down slope then frozen into white ice.

Wouldn't it be the case that Mars' lower gravity and thin atmosphere would duly cause rapid evaporation instead of freezing? Also, the title of the article describes "water flowing," in the sense of "water has flowed here." This seems to support the idea that this picture is also of light-toned mineral deposits.

Martin · Post by **Martin** » Tue Dec 12, 2006 4:11 pm

What about a meteorite. Could a small meteorite impact or debris from one, somehow cause something like this?

What about the possibility that the sand just shifted -exposing lighter colored sediment?

gsgeorge · Post by **gsgeorge** » Tue Dec 12, 2006 4:37 pm

My first post!

I noticed that the light-colored 'flow' is not the only thing that has changed from the 1999 photo. Follow the flow upwards towards the lip of the crater, and on the other side you'll notice that some sand has shifted, creating a slightly darker pile. Is this darkness the result of a shadow or has the sand actually shifted here? The bowl-shaped depression on that area of the crater makes me think there have been 'avalanches', sand-shifts, etc in this area before...

Clearly this could have been caused by high winds, possibly even a tiny earthquake. But this does not rule out the possibility that the light-colored area was water that froze or sublimated. Shifting sand from winds/earthquakes could have uncovered a small spring. Whatever it is, MGS has found something significant.

Any thoughts??

kovil · Post by **kovil** » Tue Dec 12, 2006 5:06 pm

What is the slope of that area of the terrain? I can't tell. It almost looks too flat for a landslide. The impact idea occurred to me too, but the debris trail is not what I'd expect. If it was a water caused event, what caused the water to melt? The flow or whatever it is looks to be about 800 meters.

Perhaps, if the slope is 6% or so, a small meter arrived from the lower right of the photo, and impacted the slope in the uphill direction, and the heat of impact melted the water, and some debris was carried downslope with it and that is why the lighter color, it is the deeper shale kind of lighter color material the rovers have seen earlier. There may not be any water at all, just the lighter color rock avalanching downslope.
The meteor idea, would have to hit near the lower area of a small cliff and pulverized a good deal of it, from whence it collapsed down hill.

Most of this hinges on how steep the slope is.
If it is quite flat bottom land, then it would need to be a different scenario.

A closer inspection of the origin of the flow is needed to be looked at with a higher power of magnification.

You are correct, NASA is fishing for more reasons to go to Mars !
Water being present will save us from having to take our own water there, which could be quite an onerous task. (or having to drink our own piss ! yuckky )

Dr. Skeptic · Post by **Dr. Skeptic** » Tue Dec 12, 2006 6:53 pm

http://antwrp.gsfc.nasa.gov/apod/image/ ... s_full.jpg

Most evidence of H2O an Mars shows it to be saturated with soluble compounds leaving the (white) precipitates behind as the H2O evaporates. The "white" substance is most likely not H2O but residual salty precipitates.

Liquid H2O on the surface would behave the same as H2O at 98 degrees c on Earth, quickly assimilated into the atmosphere. If the crater was the result of a comet strike the area would have residual H2O permeating the surrounding area, as erosion exposes new soil, solar energy can create a "hot spot" of geologic activity leaving the trail of precipitates, H2O being the carrier.

http://antwrp.gsfc.nasa.gov/apod/ap000626.html

Orca · Post by **Orca** » Tue Dec 12, 2006 9:54 pm

Is it too small an area for an accurate spectral analysis?

Confused wrote:Why is water a reason to go to Mars? Is it that water makes it more likely that life exists? I think the (potential) discovery of life is a good reason to send unmanned missions until we have discovered enough that manned missions are productive.

That's exactly what I was thinking. In general it seems to me that with the vast resources required to get humans to Mars and back alive, if that is even currently possible, could be more effectively spent on robotic missions. The ratio of resources to scientific value leans heavily toward robotics. But as fatcitymax suggested, the underlying motive to send humans to Mars appears to be political rather than scientific in nature.

Dr. Skeptic · Post by **Dr. Skeptic** » Tue Dec 12, 2006 10:30 pm

Many robotics missions are planned to take place before a manned mission. A trained geologist can observe and preform a basic analysis in 15 seconds for the same information the present robots are capable of in an hours time plus can maneuver data point to data points exponentially faster. Humans are far more adaptive to unanticipated findings, situations, terrain ...

Proving or disproving the existence of life an Mars may take 100's robotic missions, manned missions - who knows - less than 5?

fatcitymax · Post by **fatcitymax** » Tue Dec 12, 2006 10:53 pm

If there is one thing that the Moon missions and the Mars rovers have shown, it is that we need to expend our resources and employ the talents of our scientists and engineers toward saving the Earth from environmental destruction, not wandering around (almost surely) dead planets.

Orca · Post by **Orca** » Tue Dec 12, 2006 11:32 pm

Dr. Skeptic wrote:Many robotics missions are planned to take place before a manned mission. A trained geologist can observe and preform a basic analysis in 15 seconds for the same information the present robots are capable of in an hours time plus can maneuver data point to data points exponentially faster. Humans are far more adaptive to unanticipated findings, situations, terrain ...

As I understand it, there's little that the Apollo astronauts did that couldn't have been done...or at least could be done now...by robots. I could be wrong...

Besides, sure, it would be great to have a trained geologist on the surface of Mars. The problem is the tons (literally) of food, air and water, the radiation shielding, the medical supplies, ect ect that go along with the geologist and his/her comrades. You could build a 'hells bells' of a robotic probe for a fraction of the cost of these life-supporting supplies and their transport to Mars. I was talking about the ratio of cost to scientific gain.

It seems to me that we are talking about manned missions to Mars because it would be "cool" to send people there.

Dr. Skeptic · Post by **Dr. Skeptic** » Wed Dec 13, 2006 1:43 am

Another aspect is the human need to grow and achieve new heights, which varies between individuals. Putting all the eggs in one basket to "save this doomed world" may not be the best strategy.

The greedy consumptionism of the US and the warring religious fashions of the world will not be solved by technology and/or money.

makc · Post by **makc** » Wed Dec 13, 2006 2:06 am

Not sure why this got moved, but since I can't move it back to merge with this thread, here it goes:

PAW wrote:Today (12/06/06) they announced that they think they've found definitive evidence of liquid water on Mars.
Since the boiling point of water is a function of pressure, and since, as I understand it, the atmospheric pressure on Mars is about 90 times less than that on Earth, if any volcanic activity on Mars produced water wouldn't that water immediately boil into a vapor?
And, further, wouldn't any ice that forms from that vapor at that pressure almost immediately sublime back into vapor?

Martin · Post by **Martin** » Wed Dec 13, 2006 5:42 pm

Martin · Post by **Martin** » Wed Dec 13, 2006 5:44 pm

I will never be able to understand the ignorance behind people’s desires to prefer robotic missions over manned. Although there is no denying the value and safeness of utilizing robotic technology, I am disappointed that the vast majority of people believe that this 3rd rock from a monstrous nuclear furnace will protect them and their children and their children’s children forever.

Where does this ignorance come from? Is everyone programmed into believing that there are not enough trees to print our paper money on? Do you actually believe that when the Earth’s next major catastrophe happens you will find yourself looking into oblivion and crying out “oh if we only had more paper to print ink on then we could have afforded to learn to live in space?” If this is what is stopping us as a species from becoming a space bearing race then may be we should become extinct, eh?

Volcanoes, earthquakes, loss of or dramatic changes to Earth’s magnetic field, global warming, loss of or dramatic changes to vital ecosystems, asteroids, comets, solar flares, solar radiation, gamma ray bursts, extreme global climatic changes, supernovas, warfare, biological threats, famine, disease and pollution are just some of the threats that could lead to an inhospitable planet.

So when you find yourself saying “NASA is just looking for excuses to go there”. Please hit yourself up side your head and remember that ignorance is contagious. We must enter into space quickly before we lose our chance at continued existence. Do you really understand what is at stake here? All could be lost in an instant. We were designed to figure this out and to achieve it. Creation has given us a chance –please don’t let simple ignorance stop our progress!

fatcitymax · Post by **fatcitymax** » Wed Dec 13, 2006 6:23 pm

Clearly you are an expert at ignorance.

Martin · Post by **Martin** » Wed Dec 13, 2006 9:29 pm

Are you implying that an expert is needed to identify ignorance?

Starship Asterisk*

Light Deposits, Water Flowing on Mars (APOD 12 Dec 2006)

Light Deposits, Water Flowing on Mars (APOD 12 Dec 2006)

Don't Drink the Mars Water

3 days and 4 nights on Mars, only $27 Billion