Tuesday, February 24, 2015

First Contact – The Germ Scenario
By James and John Gaines

                The February, 2015 issue of Popular Science has a thought-provoking article by Corey S. Powell entitled “Have We Found Alien Life?” (pp. 34-39 and 70).  It reports on the research by USC scientist Kenneth Nealson into a one-celled organism called Shewanella oneidensis that appears to be able to grow uniquely on the charges from an electrode.  This allows the bacterium to “breathe rocks” in a way unlike other earthly creatures, but perhaps like others that may be discovered eventually in outer space.  The article goes on to examine, in parallel, possibilities of microbial life on other planets of the solar system and ways to go about detecting it. 
                Nealson’s discoveries, while not oriented specifically towards alien biology, bring up the sensible scenario that when we make contact with other-worldly life, it may be us doing the contacting, and the life may not be intelligent by any existing standards.  Of course, this type of first contact scenario poses a number of significant risks that have been imagined in part by science fiction in the past.  H. G. Wells’s War of the Worlds treats the matter in reverse, since technologically superior and malevolent Martian invaders are eventually laid low by germs from earth.  B-movies of the 1950’s were concerned, in contrast, with the dangers to Earthlings from germs that would come to earth accidentally.  In the case of The Blob, an amoeba-like organism survives inside a meteor and winds up absorbing the tissues first of an imprudent hermit and then of much of the population of an isolated town.  Invasion of the Body Snatchers imagines a different sort of cosmic fallout in the form of spores that grow first into exaggerated peapods and then morph into humanoid form, taking over the psyche, as well as the body, of the nearest human.  These pod creatures are not strictly speaking microbial or one-celled, but the idea is similar.  Other films, such as The Crawling Hand, feature some kind of contagion that comes back to Earth with a space explorer and spreads (in this instance with merciful slowness) into the human race before it is stopped.  It is not quite clear in The Crawling Hand that the organic processes are due to a new species or simply to radiation-induced mutations of human cells, but as one can deduce from the title, this drive-in fare is more concerned with the sexual attributes of its “Swedish” female lead than with hard sci fi. 
                In more recent times, the discovery of quasi-microbial remnants in meteorites and the apparent evidence of water on Mars have revived speculation about microbial life that could be soon proven on one of the near worlds.  Some anxieties have arisen over the possible contamination of our own ecosystems by these strangers.  During the exploration of the Moon by Apollo astronauts, there had been relatively little concern that moon rock samples might pose any dangers.  For one thing, there was ample evidence that the Moon would be sterile, given the fact that water was not positively identified there until after the missions were finished.  Secondly, the samples were quite limited and were subject to careful scrutiny.  Thirdly, the astronauts themselves functioned to some degree as canaries in the coal mine, since the return to Earth was not instantaneous and any glaring peril might presumably unveil itself during the flight back.  After extended examination, moon rock samples were eventually distributed far and wide, so the fact that they have produced no discernible damage proves retrospectively that any anxieties were unnecessary.
                However, this comforting lack of extraterrestrial life so far may not hold true for future expeditions.  Asteroids, the immediate target for NASA missions, might seem to pose no greater danger than the moon rocks.  We must keep in mind, though, that one important goal of asteroid encounters is potential mining.  One wonders if importation of tons of material would be treated with the same scrupulous care as NASA’s tiny samples, especially if the goal were not pure science, but commercial capitalization.  This still limited risk is multiplied many times when it comes to samples from some of the other interesting bodies in our solar system, such as the moons of Jupiter, Saturn, and Neptune.  Besides satellites like Triton and Europa, which might have submerged liquid seas, other worlds may sustain underground microbial life.  Powell’s article specifically mentions Mars, Titan, and Ganymede as places that might sustain rock-consuming microbes not dissimilar to the ones discovered by Nealson and his team.  In regards to the Saturnian moon of Enceladus, Powell says, “hydrothermal vents below its South Pole… would be natural homes to rock-breathing microbes” (35).  NASA certainly embodies much of mankind’s present knowledge about biochemical contamination and could be counted on to apply what it knows, but in view of severe budget restrictions and the general neglect of much hard scientific R & D on a worldwide scale, we wonder if what we know now might really be enough to protect our planet against possible contamination. 
                In this regard, two additional B-movies deserve consideration.  It! The Terror from Beyond Space and 20 Million Miles to Earth postulate more substantive imports in the form of vaguely reptilian and bipedal creatures that are brought back on spacecraft.  In It!, the importation is strictly involuntary and unknown until after the return trip is initiated.  The ET kills several of the crew and menaces others before a drastic solution is found in the form of depressurization of the ship.  This was a good enough idea that it was duplicated years later in the film Alien, where the danger of exposing Earth to its dragon-like creature was far more explicit.  In 20 Million Miles, on the other hand, the importation is deliberate and the Venusian is thought to be utterly harmless until it is exposed to the air and rocks of Earth, which make it grow into a giant that terrorizes Rome before succumbing to a mere bazooka.  Leaving behind the sensational appearance of both monsters, let us ponder the means of transmission rather than the exterior, since a real danger may not come from something that roars or looks like a dinosaur.  The It! scenario, where a stowaway bacterium would not be discovered until it is already on the way to Earth and holds, so to speak, a human crew as hostages, is a frightening possibility.  In a worst case, it might lead to the termination of the mission and its human component.  A 20 Million Miles eventuality might be all the more ghastly, since control on our own planet could not be preserved simply with nets or bazookas. 
                Returning to the Nealson characterization of his organism as “rock breathing,” it may be worthwhile to examine a particular risk of an organism “hiding” itself inside the Earth.  Humans generally tend to think of the Earth as a vast machine for decontamination, rendering harmless everything from nuclear waste to plague remains.  However, what if a rock breathing microorganism got under the surface of our most important rock – this planet?  We who are mainly limited to controlling the surface of the planet do not currently possess the means to reasonably decontaminate the Earth itself I an alien microorganism managed to establish itself below us.  What could be the potential effect of a life form that could digest the very underpinning of our existence?  Only one sci fi example exists, as far as we know, of such a threat to Earth’s minerals, the rather far-fetched film Monolith Monsters, in which alien crystals begin to grow disproportionately and dehydrate any living things that come in contact with them.  Ironically, they are easily conquered when a dam is breached near a salt flat and the flood of sodium chloride dissolves them into harmless sand.  Yet this threat is literally superficial and does not begin to approach the complexity of having to deal with a harmful organism proliferating underneath the outer crust of the Earth. 

                So to “get real” with this admittedly unusual sort of scenario, what could be done?  First, it seems prudent that a containment area away from the Earth would be a good idea.  The Moon might be a possible candidate, but let’s not forget that, thanks to tides, the Moon is also an important part of the Earth’s environment and may not make a good celestial guinea pig.  Better would be a moon around the Moon, since NASA is already proposing to tow an asteroid into lunar orbit as part of its preparation for missions to the Asteroid Belt and Mars.  Such an installation might cost more than one on the lunar surface, but would add a useful degree of separation in a worst case situation.  Secondly, it would be important to test possibly life-bearing samples not only in a vacuum, but in simulated Earth-like conditions.  If earthbound industries and laboratories are the eventual destination, it follows that we would have to be sure that organisms would not get out of hand if they were exposed to oxygen, moisture, cosmic ray protection, and the other privileges we enjoy.   Lastly, some consideration should be given to conducting materials processing at a location above the Earth’s surface.  This would be enormously expensive in the beginning, but might actually pay for itself to some degree by greatly reducing the mass of material that would have to be moved from space to Earth, given the fact that navigating our atmosphere is the most expensive and dangerous part of such transport.  Ultimately, it may be impossible to completely eliminate the danger of harmful exposure to organic life if we are determined to travel beyond our present home.  On the other hand, failures like the Challenger disaster should convince us that safety has to come first, especially on a planetary scale.