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Ned Potter is the science correspondent for ABC's "World News with Charles Gibson." He has reported on such topics as space exploration, the human genome and climate change.
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Water on Mars? Not So Fast
February 29, 2008 4:15 PM
Maybe it was a nice idea while it lasted. In 2006 a team of scientists published two images from NASA's Mars Global Surveyor probe -- the first, from orbit in 1999, showing the slope of a crater, the second, from 2005, showing that something had created a gully in the crater's side.
What could it be? The researchers at the time said they thought it could be water, spurting from underground and freezing as it slid down the crater wall. But today a second team says...maybe not.
To review: Here's that image from 1999:
And here's the second, of exactly the same spot, six years later:
Tantalizing, no? “We are talking about liquid water that is present on Mars right now," said Ken Edgett, the scientist who led the analysis, at the time. "It could be acidic water, it could be briny water, it could be water carrying all types of sediment, it could be slushy--but H2O is involved."
But now, Jon D. Pelletier and colleagues at the University of Arizona in Tucson have reexamined that crater wall, using higher-resolution imagery from a newer probe, Mars Reconnaissance Orbiter. They've also done some computer modeling, and they conclude that a small landslide -- sand or gravel -- is a better explanation for what the orbiting cameras saw. The deposit could have some liquid in it, but water would spread slightly differently as it came down the slope, especially at the bottom.
Take a look at the newer picture, and the Arizona team's interpretation of it:
I traded e-mails with Pelletier and with Alfred McEwen, one of his co-authors. "If it was bright due to water ice it should have disappeared in the summer or at least changed shape if being resupplied somehow, but instead it had the identical outlines after a full summer," McEwen wrote.
"I was surprised," says Pelletier. "I started off thinking we were going to prove it's liquid water." The team is publishing its conclusions in the journal Geology; the abstract is HERE.
To a lot of people this finding may feel disappointing; many scientists studying Mars will openly admit they want to find water there. But as MeEwen wrote, "we should always be skeptical, especially about a brand-new observation and preliminary interpretations."
February 29, 2008 | Permalink | Share | User Comments (36)
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The truth of the matter is not only "many scientists studying Mars will openly admit they want to find water there" .... the theory of evolution needs it too. The uniqueness of the Earth is too uncomfortable for them.
Posted by: CM Loke | Feb 29, 2008 5:34:56 PM
Of course not, That is so absurd to say it is proof of water in one place like that on the side of a crater. It is a landslide. I always knew it was a landslide. People are so desperate to try to prove their ideas that they lose touch with reality.
Posted by: Rich | Feb 29, 2008 5:51:32 PM
How about cleaning up the flaming fithy mess you have made on this planet before you stick your primitive american clapped out space junk on other planets
you know nothing about his planet,..now you want to search for oil and gold on others?
get real stupid Toxic Americans
Posted by: AJ | Feb 29, 2008 6:53:20 PM
This does not disprove the existance of water on Mars, it doesn't even disprove the possibility of liquid water on Mars. It only shows that in this particular instance it probably was not liquid water. Maybe we can get AJ to go look for it.
Posted by: Quietman | Feb 29, 2008 8:03:38 PM
Perhaps, perhaps. We won't know for sure until we get there, and we'd damned well better get there to find out. Otherwise, we'll be committing slow suicide by total ignorance. If we don't look, we'll be nothing more than primitive savages wondering about the lights in the sky. Find out, find out, find out. Then we'll know, one way or another.
And, yes, I'll be the first to volunteer aj for the job.
Well, the second, Quietman.
Posted by: Andy | Feb 29, 2008 8:13:52 PM
I guess that makes me the third!
All the new information shows us is that we don't know everything, gotta go and see it - well after AJ lets us know it's OK.
Posted by: Andy Clark | Feb 29, 2008 8:22:12 PM
Hey, Quietman! I came back from the other side of the deep dark black place of the nothingness of cyberspace. Well, not really but it makes no difference if there is any form of H2O on Mars because it has already been determined there is no life there. So even if there are billions of tons of ice beneath the surface, it makes no difference at all because there are not even microbes there.
Well, other countries are not that much better than Americans to be judging them so harshly. In fact, in many ways they could be worse. So what does that prove? Nothing at all except that it is not too smart to be berating other people. (and at least I am not a clone like some of these other people seem to be.)
Anyway, Andy, our salvation does not depend on us getting to Mars. It could be more of a trap than anything. We should just be content to enjoy life fully (which is what Shalom is).
I can't say too much about God or I will have to go back into the deep dark blackness of cyberspace deletions.
Posted by: PQQAm | Mar 1, 2008 9:00:51 AM
The moment I first saw this picture, I was telling people at work that these "scientists" are crazy. It is so obvious to anyone who has any kind of real experience with nature that it is a landslide. They are making the rest of us look bad. They are making good money to make us all look silly.
...and I do agree with what CM Loke said. If the historical record, as we have it, is true, they could have a lot to lose and a lot of explaining to do.
Being held responsible for what we say and do, that is a novel idea!
Posted by: Daleri | Mar 1, 2008 9:19:25 AM
PQQAm
The need to know if life is there is partly academic - some of us are curious. It's also partly in the interest of our use of the planet - is there a chance that we could disturb an existing form with our presence or would it be a danger to exploration.
And the importance of water is for selfish reasons. We want to go there and be able to return.
Evolution falls under the academic interests - not under the practical interests.
Posted by: Quietman | Mar 1, 2008 1:55:05 PM
It seems some people take any reason to bash science
Posted by: WDJ | Mar 1, 2008 2:17:25 PM
It's to their credit as scientists that they admitted what they found was not what they wanted. I feel a lot more comfortable with these people than the evolution pushers.
Posted by: JimmyDaGeek | Mar 1, 2008 3:10:15 PM
CM Loke
The uniqueness of the Earth is thus far only in this one little solar system. We do not yet have the technology to determine if it is truely unique.
Posted by: Quietman | Mar 1, 2008 3:10:19 PM
PQQAM
Re: "Nothing at all except that it is not too smart to be berating other people."
I said nothing at all to berate, merely suggested that since Americans are so stupid and toxic that he would be much better qualified to go look.
Posted by: Quietman | Mar 1, 2008 3:21:43 PM
This is how science is supposed to work. One group collects data and interprets it, and publishes it for others to review. If someone else thinks the interpretation was wrong, they publish their evidence for saying so. If it still isn't resolved, they or someone else figures out how to test the alternatives. Eventually a consensus is reached - the strength of the consensus depending on the strength of the evidence. New evidence, who knows? That's what makes it exciting.
Posted by: jock59801 | Mar 1, 2008 3:24:24 PM
And consensus is ONLY used where there is not as yet any means to prove that a hypothesis is correct and all others wrong. At that point a consensus is no longer required. For example: The world has been proven to be a globe, it requires no consensus.
Posted by: Quietman | Mar 1, 2008 5:53:57 PM
Hi Quietman,
No, I wasn't aware of that. I don't know how the comments work anyway. It looks like my other "blog" type comments are still there. I only care about the science discussions anyway, so maybe I'll just stick to this. The rest is pretty much a waste of time.
Posted by: jock59801 | Mar 1, 2008 6:00:54 PM
I think I use the word consensus fairly loosely. I know in some deliberative bodies, such as the U.N., "consensus" generally means unanimous. That certainly is not my intention when talking about science. I basically just mean that the large majority of scientists that I respect seem pretty confident about it. I don't know how other people view the word when it is used so much in the climate change debate. There the percent that seem quite confident is well over 90% (really it's probably over 99%, but I don't want to get into any stupid arguments over dueling lists of scientists). That is a good enough "consensus" for me, but of course that doesn't mean it is absolutely certain, although I think it makes it likely enough to prompt action.
Posted by: jock59801 | Mar 1, 2008 6:10:44 PM
jock59801
I concur, unanimous or close to it. I was thinking of science, more along the lines of paleontology or climatology where absolute proof is elusive.
Posted by: Quietman | Mar 1, 2008 6:31:55 PM
Well, there are consensuses and consensuses. There is a consensus among those who believe that pi should be 3 even, and there is a consensus among those who believe that hell awaits those who don't follow the "true" beliefs. I would also believe that there is a consensus among those who believe (and those who don't) about water on our neighbor, Mars. Who is to be the final judge? We'll probably need a consensus there, too. The only real way to end the discussion, one way or the other, is to get ourselves hence.
Posted by: Andy | Mar 1, 2008 6:43:09 PM
Andy
Re: "get ourselves hence"
My point exactly.
But I thought the consensus on Pi was to use 3.1417 for more seriuos calc and 3.14 for GP use.
Posted by: Quietman | Mar 1, 2008 6:49:41 PM
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