Thursday, January 26, 2012

Barsoom

Hubble Space Telescope image of the Acidalium hemisphere of Mars, 1995

I mentioned in a comment on the Megaupload post that I opened one of my old websites the other day, one I first created some time in 1997 or 98, I'm not sure, haven't updated since 2001, and which I hadn't even looked at for years.

It was a site about Mars, the Red Planet, the Mimic Planet as I came to call it, "Barsoom" as known by its inhabitants in Edgar Rice Burroughs's novels, which was being heavily featured in space science communities at the time because of the unprecedented images of the surface being returned from the Mars Orbital Camera.

These were stunning pictures that show things that in many cases are still unexplained. Which doesn't mean they are necessarily the work of Aliens, but only that the surface of Mars is telling us things we have yet to understand, and part of our failure to understand is due to the paradigms we use when observing. If we aren't thinking openly, we can't see clearly.

In the case of Mars, the problems of observation are long-standing, going back at least to Schiaparelli, but compounded by Lowell, and made even worse over time by the planetary science community which has its own set of biases and peculiarities, and is subject to a kind of authoritarian belief system that disallows innovative perspectives.

Telescopic observation of Mars is still quite interesting -- I find it fascinating myself, even with the relatively primitive telescopes I've used. But the orbital cameras and the landers of the space program have provided a startlingly different view of the surface than can be had from any telescope on Earth, and an honest assessment of that view shows that Lowell may have interpreted in error (as do we all about many things) but his vision -- if you will -- strikingly parallels what's actually there on the surface, but at a completely different scale than he saw it.

I've been to the Lowell Observatory and seen some of his primary materials and have come to understand somewhat better how he could believe what he did about what he was seeing through the telescope. Yes, he saw a surface that showed distinct linear patterns, dotted with circular spots here and there, and he saw darkenings and lightenings and other things that he interpreted erroneously. Yet closer to the surface, much closer, the orbital cameras showed that many of the things he thought he saw at a telescopic distance (but which are not visible -- at least to most people -- at that scale) are actually there -- or things that look like what he saw are there, though at a much smaller scale. So is much else besides, things that he never dreamed of.

Interpretations of the surface of Mars have been complicated since Lowell's time by the debate over the presence or absence of liquid water. Lowell claimed that he saw linear features on the surface that he interpreted as canals and that most likely water flowed in those canals to enable irrigation of parts of the surface. Other astronomers vehemently disagreed. They asserted there was no water so there was no point in canals, and the whole thing was just stupid, nyah, nyah. Unfortunately, this is the way some scientists are, and because Lowell was an outsider, a Boston Brahmin, and a writer, not a scientist at all, he was treated with a certain level of contempt by a portion of the planetary science community of his day, and his work was constantly being denounced -- as well as popularly accepted, in part because he was a good writer.

It had been obvious since the days of the Mariner 9 in 1971 that the surface of Mars had been heavily shaped by flowing water; dry riverbeds seemed to be everywhere. Yet there was no visible water at the surface now, and many of the features that were assumed to have been carved by water didn't quite "look right." There was something going on that didn't quite scan, but nobody quite knew what it was.

It was long assumed that the polar caps were mostly carbon dioxide -- and very thin at that -- but that was found not to be true. The caps were found to be quite thick and finely layered, and they were mostly water ice, with an annual carbon dioxide deposit that came and went with temperature. The permanent caps are nearly entirely water ice. The behavior of the CO2 caps was and is remarkable. The surface near the poles, especially in the south, can become very active with geysers blowing dark sand and CO2 gas into the atmosphere in startling displays, one of which I believed -- and believe -- was captured in action by the orbital camera but was misinterpreted at the time and still is, though the activity I say it depicts is now widely accepted within the planetary science community as real and frequent. They will not accept that the image actually shows the geysering taking place, however, due to the technical details of the capture of the image.

This is the image that I cropped from a larger one and colorized and showed as possible evidence of geysering near the south pole. This was well before it was widely accepted that such geysering does indeed take place.



From this crop, it looks pretty obvious (at least to me) what is going on, but many of those who have seen the image strenuously deny it shows what it seems to show, claiming that the apparent appearance of geysers in action is merely an optical illusion (they are so common on Mars; remember the canals!). In fact, say the skeptics, according to the image data, the picture was taken from almost directly overhead, not at a glancing angle close to 30° which would have been necessary for the appearance of actual geysers geysering. Thus, what we actually see here is the surface appearance seen from directly overhead, after two separate incidents of outgassing (or some other process) which occurred at different times under different wind regimes. There are many other images which show similar patterns of dark deposits at almost right angles to one another.

Of course, I being stubborn continue to insist that I am right and the skeptics are wrong; for the emission angle of the image doesn't necessarily reflect how the image is processed, since many images taken at relatively low angles were processed to look as if they had been taken from directly overhead. The data that appears on the image record doesn't necessarily reflect what happened from the time the image was captured until it was released. Etc. Etc.

This is a futile argument, however, and these days, since the geysering phenomenon is now widely accepted -- but not widely known of outside the planetary science community -- what this picture actually shows is essentially moot. Yes, it is an image that looks to show what is widely accepted as taking place on the surface, though skeptics say it doesn't actually show it. Got that?

Many other issues like that were being batted around back in the day: was there evidence of glaciers on the surface today? Was water being released at the surface? Could water even exist at the surface? And so on.

There were so many opposing camps, and the arguments were more on a political plane than a scientific or even straightforward observational one.

The political positions about Mars came to dominate all other considerations, and this seemed to me to go back to the Lowellian era of telescopic observation and popular culture. There was a time, for example, when Gil Levin (project scientist on the Viking Mission who asserts that evidence of life on Mars was found by the Vikings) questioned the color manipulation being done by the image processors at JPL, manipulations that eventually produced some of the oddest sky and surface colors imaginable for Mars, and almost always obscured the actual sky and surface colors. Levin began to speak out about it from early on in the Viking mission and he became more strident as time went on because he felt that the manipulation was a deliberate (if pious) fraud intentionally done to disguise actual findings -- such as what he believed was evidence of biology on the surface of Mars.

The official defenses of the color manipulations -- some of which were patently absurd -- revealed the political basis of many of the pronouncements about Mars; science -- or even simple and accurate observations -- had to take a back seat to Mars science politics. And that has always been about who is doing the asserting and interpreting and what their position is in the pecking order.

To this day, Gil Levin's arguments in favor of a biological interpretation of the Viking findings are largely suppressed and unknown outside a circle of enthusiasts. He broke with the consensus of his peers, and doing that is perhaps the surest way to perdition known to mankind, especially in the sciences.

All that aside, it eventually dawned on me that probably everyone was wrong about Mars, and that what we were seeing and sensing remotely with our spacecraft was probably not at all what we thought it was. Interpretations relied on "water" -- and I came to realize that that was probably the key error.

Water there is in abundance on Mars in the form of ice and vapor, but the fluid that has flowed and ponded at the surface of Mars has probably never been "water" as we would understand it, that is pure or somewhat salty. No, it's more likely that much of the evidence of flowing water on the surface of Mars is actually evidence of flowing aqueous solutions of sulfuric acid, and that changes everything.

First of all, sulfuric acid can remain liquid under Martian conditions far longer than pure or salty water can. The mythology has long been that "liquid water can't exist" on the surface of Mars, which is something of a falsehood, because liquid water can and does exist on the surface to this day and landers have from time to time produced images of it, most startlingly the drops of water that clung to the legs of the Phoenix Polar Lander after it landed on a patch of ice.

Of course, there are those who dispute any such thing ever happened, pshaw. So it goes.

My own view now is that though there can be liquid water at the surface of Mars, and it can persist for some time in a liquid state without freezing or evaporating/subliming "instantly" as the Mars Myths insist must occur, it doesn't matter that much because liquid water is and has always been rather rare at the surface of Mars. An aqueous solution of sulfuric acid has been far more common and is probably the volatile that has carved most of the evidence of "flowing water" on the surface.

Almost all of this flow, of course, has come from the interior. It is probably still in a liquid state fairly near the surface, primarily in and near the vast Northern Lowlands. These lowlands may have once been an open ocean but not of liquid water. As a sulfuric acid ocean, it would appear similar to an ocean of water, but it would behave very differently.

For one thing, it would neither freeze nor sublime under typical Martian conditions. It would instead remain liquid, though it might become more viscous at low temperatures and pressures, neither a slush nor a gel, but somewhat similar to them, thick and slow-moving. A cold sulfuric acid lake or ocean would be very placid compared to an ocean or lake of water.

There are many craters that show evidence of repeated flooding from below. There are remnant deposits in some of these craters (they are often referred to as "White Rock" deposits) that show hundreds of layers, all of which are approximately the same thickness (a few meters or less). These formations were long mysterious and enigmatic.

Then the Opportunity craft landed in a crater in Meridiani Planum that showed "white rock" around its rim.

Studies were undertaken.

The "White Rock" -- in Meridiani at least -- turned out not to be "rock" at all. It was a sulfate deposit. A layered sulfate deposit. Within which and all around which there were little blue balls of an iron precipitate called hematite. Oh. My. Goodness. What the hell?

This spectacular finding was cited by a very excited project scientist Steve Squyres as proof positive that the landing site and all around it had been "soaked in liquid water." Meridiani had to have been formed in a liquid which Squyres initially insisted was water; there was no other way.

Well, except... Actually formation of what we see would imply that the liquid was actually a fairly saturated solution of sulfuric acid, not water as we would commonly understand it at all. In order to get those kinds of precipitates, especially in those quantities, the solution would have to have been close to super-saturated, but even a mild saturation would imply that the "water" was no longer water at all, but was instead the equivalent of battery acid, and adding even distilled water would still leave you with an aqueous solution of sulfuric acid.

That understanding changes everything. If much or most of the "water" that has ever been at the surface of Mars was actually a strong sulfuric acid solution, what does that say about the possibility of biology on Mars? Is it even conceivable? I'm not saying it isn't, by the way. What I'm suggesting is that the question needs be explored more fully. If sulfuric acid is and has been the predominant volatile liquid on the Martian surface then the implications for biology and evolution are quite different than if the volatile has been water.

Ultimately, Squyres himself came around to the view that "water" as such was unlikely as the volatile agent at the surface of Mars, that it was probably sulfuric acid at considerable concentration. But I've seen very little followup to the implications and consequences of a sulfuric acid as opposed to a water regime on Mars.

I stepped back from the Mars questions when it seemed that the discoveries being made were confounding expectations too much for a clear understanding to materialize. Mars is a planet of deception and illusion and what we may think we see there is... really something else.

A new lander called "Curiosity" is expected to land in Gale Crater in August. Given the nature of the site, I don't doubt there will be surprises.

The Face on Mars is still there after all, still staring into space, still wondering...

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