Monday, February 25, 2013

Mars (Still) Awaits

Mars! Bitches!

Getting to Mars Edition -- Saturday was PBS Science Cafe Day at Los Poblanos in Albuquerque. We've been signing up for this event pretty much since we've been in New Mexico. It's a rather easy-going opportunity to get together with some like-minded coots and other space and science junkies (of which there are many in NM) and hear some talk about what's happening in the field.

Saturday, the field was "Mars and how to get there." Sending humans to Mars, it was confidently asserted, has been a Dream of Mankind for Centuries. Has it? Being the skeptic I am, I questioned the premise right off. Has Mars been a long-sought destination for Mankind for... centuries?  I think not. The Destination factor of Mars has only been around since the age of rockets that made probing the Solar System and beyond a possibility -- if not always a probability. But the issue wasn't really how long Mankind has set its sights on the Angry Red Planet.

The issue was "Why Anyone Would Want To Go To Mars?" And once anyone decided to go, how would they do it?

These issues are being intensely wrangled at various sites in New Mexico as well as around the world. One of the visual aids brought by the speaker was the April 30, 1954 issue of Collier's Magazine featuring articles on Mars by Wernher von Braun, Cornelius Ryan and Fred Whipple, but mostly featuring the striking cover art by Chesley Bonestell seen above.

Well, yes. Without the cover art on popular magazines, and without the enormous number of science fiction movies produced in the 1950's, I sincerely doubt many of us would give Mars more than a passing thought. If that.

Because there was so much popular media focus on Mars when we were children, however, the planet has become a kind of ingrained Place In Space for a lot of people of my generation. But I've got to wonder: do younger people, especially much younger people, give a good gott-damb?

Plenty of spacecraft have visited Mars during my lifetime. The statistic we were given yesterday -- if memory serves -- was "Earth 15, Mars 24" (as in fifteen successful Mars-destination spacecraft, twenty four unsuccessful.)  There have been many discoveries. But oddly there have been none that either confirm or refute many of the various theories about Mars and its potential to harbor biology that have cropped up over the years.

Especially, there has never been a direct effort to confirm (or refute, for that matter) the rather baroque theories of super-oxides in the soils which were offered to account for the failure of the Viking missions to discover life or even organics on the surface of the planet way back in 1976. Nor has there been any direct effort since 1976 to confirm or refute the supposed sterility of the Martian surface.

This has long struck me as very odd behavior by the planetary sciences. The Viking biology results were enigmatic and contradictory to say the least; however, the scientific consensus at the time was that the surface was sterile, and the theory offered was that a combination of soil super-oxides and ultraviolet light destroyed carbon compounds as they formed or arrived on the surface so that there were none to found. A priori, that meant there was and could be no biology on the surface. Case closed. Move on.

While this consensus may be correct, it has never been tested. No trace of super-oxides have ever been sought or found at the surface of Mars, and no measurement of ultraviolet flux has ever been made at the surface. The presence of liquid water -- or some liquid at any rate -- long confidently asserted to be impossible at the surface, has been rather dramatically confirmed in a little known series of Phoenix lander images that show droplets of something on the landing struts of the spacecraft.

Personally, I'm quite leery of asserting that it is "water" in the sense that most of us would recognize it. Due to the fact that the Phoenix landed on a patch of ice which appears to have sublimated and condensed in response to the heat of the landing rockets, the proposition that it is water seen on the landing struts makes sense; yet the behavior of the droplets -- appearing to remain on the strut and remain liquid throughout the mission -- is not the behavior expected of water at the surface of Mars. Any water that was released by the heat of the rockets striking the ice below the lander should have either sublimated immediately or if recondensed, it should have refrozen within minutes; there should have been no detectable liquid phase at all.

And yet, there those droplets are, and there they persisted. How could that be?

I proposed that it's not water. It is instead a brine or an acid that remains liquid at typical Martian temperatures and pressures, and that furthermore, many of the apparently water carved surface features on Mars were actually the result of flowing brines or even a strong solution of sulfuric acid. There may never have been much water -- as such -- on Mars throughout its entire history and there may be very little there now, and what there is may all be frozen as ice.

I could go on at great length about these matters, and have done so in other fora, but yesterday it was the turn of New Mexico Space History Museum Director Chris Orwoll to hold forth on the topic of how to get to Mars and why bother -- oh, and his own journey from submarining in the Navy to his current perch at the museum outside of Alamogordo.

Getting there is being worked out as we speak, the major difficulties being the hazards of cosmic rays and meteoroids, both of which have damaged near-Earth orbiting space satellites and laboratories, and the sheer amount of stuff that has to be carried on the voyage and will be necessary to pre-position on the surface of Mars to supply the needs of landing crews. It's much simpler just to send a robot, as of course has been done many times in the past and will continue to be done for the foreseeable future. Getting people to Mars -- even though it is quite feasible right now -- may be a long time in coming, in part because it is very expensive, there is little current impetus for additional manned exploration of the solar system, and public sector budgeting for space exploration looks rather dismal indefinitely. The private sector is not picking up the slack.

While it wasn't mentioned yesterday, there's a rather good two part teevee movie out of Canada that dramatizes some of the issues involved in manned expeditions to Mars called "Race to Mars" which I recommend as a primer. While I enjoy the many Mars movies made in the past, they tend to be locked in their own time period or to foster highly dramatic but not necessarily apropos story-lines.

Documentaries as opposed to dramatizations often leave out human nature and how people respond to crisis, focusing more on hardware than the people taking the risks and making the voyage. "Race to Mars" strikes an interesting balance and features relatively recent (well, up to 2007) discoveries and understanding of the Martian surface and conditions.

Getting there is almost the easy part. What to do once there is the hard part. The final scene in "Race to Mars" shows the establishment of a little colony in Dao Vallis, where the fictional pioneering Olympus expedition had struck water -- and lost a crew member when the water gushed out as a snow and ice geyser destroying the drilling apparatus.

Water, of course, is the prime necessity for any human colonization of Mars, but whether there is any currently available -- even deep underground -- in Dao Vallis is something of a mystery. Dao is an ancient outflow channel in the Southern Highlands, arising near the Hadriaca Patera volcano and debouching into the Hellas Basin, the deepest hole on the planet. There likely has been substantial water and ice in this region, but whether they are there now -- at least near the surface -- is doubtful primarily because these features are very, very old, dating back nearly to the origin of the planet.

There are much more recent "watery" features, and as noted above, the Phoenix craft actually landed in 2008 on near-surface ice and released something ("") that stayed liquid at the surface for quite some time. If there is water to be found on Mars today, it is likely within meters if not centimeters of such surfaces -- high in latitude, low in elevation.

On the other hand, the Hellas Basin, Dao Vallis, and the surrounding terrain are relatively low latitude (ie: in places much nearer the equator than the pole) and low elevation (the lowest on the is planet found in the Hellas Basin) and are more likely to sustain liquid water near the surface than any other location in the Southern Highlands.

It was patiently explained to me by a planetary scientist some years ago that the Hellas Basin is unlikely to contain any liquid water today (though it may have done so in the past) because of an ongoing process of freeze-drying, similar to what happens in a frost-free refrigerator freezer. Evaporation and sublimation such as is likely to take place on Mars can maintain a frost and fluid free environment indefinitely even at relatively high temperatures and and atmospheric pressures.

The basic question remains, "why go to Mars?" And the answer is always the same: "It is human nature to explore and go where no one has gone before." Once the urge to explore fades, the progress of civilization is reputed to end.

Here's the problem, though. Too many times, those who are most intent on exploration of new frontiers are the very ones who threaten -- and often cause -- the extinction of the civilizations they encounter and/or the ruin of the pristine environment they claim.

I suspect Mars is such an inhospitable place -- whether or not it hosts native biology -- that any effort to colonize the planet from the Earth will be fraught with peril and failure to no apparent object. No one expects to find gold or jewels or a functioning civilization on Mars -- all of which were impetuses for exploration and conquest on Earth. There is no one to exploit. There are few or no resources to control. There is almost nothing that could sustain a modern expedition let alone a comfortable lifestyle on Mars. Whatever is found there in the by and bye, it won't be sufficient to sustain a viable human society. At least not as we know it.

The closest analogues on Earth to potential Mars colonies are the science outposts on Antarctica and the telescopes high on the Atacama Plateau in Chile. Neither is even remotely self-sustaining, nor could they ever be in the future. Such is almost certain to be the case on Mars should a colony ever be established there. The question is not so much one of getting there, it is more about maintaining a presence once there.

At one time, after all, it was widely believed -- or at least said -- that conditions at the surface of Mars were almost certainly almost instantly lethal to any and all carbon-based biology; even the slightest contact with the surface dust could be and probably would be a death sentence to terrestrial visitors. Surely the ultra violet flux and lack of protection from solar radiation and cosmic rays would take care of any survivors of Mars dust exposure.

The lethality of the Martian surface is yet to be proved, but it is still not a hospitable place no matter what.

Almost 60 years ago in the Collier's article linked above, Wernher von Braun, the father of (Nazi)German rocketry and the American space program predicted that it would take a century for Americans to prepare sufficiently to undertake a manned expedition to Mars.  That was pre-Sputnik, when there was no American or international space program to speak of.

The space program has once again fallen on (relatively) hard times. NASA lacks focus and budgeting for major space exploration programs is not likely to be abundant for many years to come -- if ever again.

Sixty years ago there was no lack of imagination, however, and it seems to me that we've lost the ability to envision the future. Without that imagination and vision, progress as we have known it ceases.

So just what in tarnation is this thing on Mars, anyway?

Shiny Thing On Mars -- Dubbed The Faucet Handle

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