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Walk Tall, but Please Tread Softly, SpaceX

The views expressed are those of the author and are not necessarily those of Scientific American.

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A Falcon 9 launches the Dragon spacecraft - which orbited and then reentered the atmosphere to splashdown in the Pacific in December 2010 (SpaceX/Chris Thompson)

We live in interesting times. Just as NASA’s most recent budgetary rearrangements seemingly threaten the very core of solar system exploration, with cuts that might pull the agency out of its participation in exciting efforts with Europe on the ExoMars project, the private space industry appears to be on an accelerating course to more real flights, real missions, and real exploration.

Elon Musk, the driving force behind SpaceX, has expressed his clear intentions to not only get humans to Mars in the next 10-20 years, but to get lots of humans to Mars, perhaps 10,000, perhaps many more. Such hubris could seem a little silly coming from almost anybody else, but Musk is poised to turn the spaceflight business topsy-turvy, making the missteps of others appear positively comical. If SpaceX says it’s going to Mars, it means it. Musk’s stated long-term motivation is nothing less than to ensure the survival of the species, by making us a multi-planet race. Funnily enough I find myself agreeing with him on this point, but (as I’ll describe below) also very nervous about what happens during the process.

The objection that people typically make to his kind of announcement is pretty hackneyed, and it goes along the lines of “we have enough problems here on Earth without spending money and resources to go to other planets, think of all the things we could solve here first.” Well, yes, and no. This is part of a much bigger debate, but I think a couple of points are worth mentioning. First, it seems pretty clear at this stage in human history that no successful large society really solves its problems by forgoing activities that push technology, science, exploration and inquiry forward. There is simply far too much momentum and dynamic change in a large human collective to keep it in safe stasis. Like it or not, the problems of our overwhelming presence on this world (in numbers, thirst, and hunger) are very, very unlikely to be solved if we just divert all our resources to medicine, green energy, and good deeds. This is not to say that we shouldn’t be chasing those things, but rather than senselessly trashing exploration and basic science to shore up resources we should try to stop waging wars and try to halt truly dysfunctional economic practices when we spot them (phew, there, I said it).

In the grand experiment of evolution we have a remarkable opportunity to put members of our kind on other worlds. Even if, like Mars, these places are far from comfortable, they are really only another extreme environment, and we’ve become very, very good at coping with those. It may be that going interplanetary is ultimately too challenging, but we won’t really know until we try, and I think there is greater risk for the distant future of our species if we don’t make the attempt.

Cute, but do we want these on Mars? (National Park Service)

But there is a catch with a gung-ho approach, and it’s a basic one, with many precedents here on Earth. Take for example the case of the genus Rattus, the not-so-humble rat. Over the past few centuries the flourishing of European and Asian ocean travel and exploration has allowed stowaway rats (particularly the Black, Brown, and Norwegian varieties) to jump ashore on over 90% of the world’s islands and island chains. The consequences have been devastating for seabird populations, rats are hungry little buggers, and eggs and chicks are a veritable a la carte menu for rodents. Other native species also suffer as rats gobble up fruits and seeds, disrupting the entire food chain. Some thirty percent (about 100 species) of seabirds are now considered to be at risk of global extinction, and the prime culprit is accidental rat contamination on previously isolated land masses. Exactly what this is going to do to the global environment over the long term is unknown, the physical isolation of these places is still a buffer, but for people living in some of these places it profoundly alters their otherwise sustainable economies and livelihoods.

Earth’s recent history is littered with stories like this, and its deep past is undoubtedly also replete with ‘contamination events’ caused by either instinctively driven migration and exploration of species, or sheer random chance. There is however one critical difference when it comes to human-driven events, we may have selfish and intellectual reasons to want to intervene and prevent such things. A defining characteristic of our species is the ability to observe and learn. It has served us incredibly well in the ferocious and unforgiving torrent that is biological evolution, and we’ll need it if we want to carry on across the solar system.

From a planetary contamination point of view one of the dirtiest things you can place in a pristine environment is an organism like a human, replete with our 100 trillion cells of microbiome each of us is a walking bio-hazard. We breathe out, we excrete chemicals and waste, our skin is constantly shedding. It would be next to impossible to keep ourselves isolated from the martian environment – especially if there were 10,000 of us there. Obviously we don’t know how bad a thing this might actually be, Mars could be (and have forever been) utterly sterile, in which case we’d not precipitate normal ecological disaster. But we might still want to be very careful about what microbial populations we first unleash; although bacteria are smaller than rats, they’re many times more potent.

Perhaps a more likely scenario is that Mars is no stranger to contaminants (an argument I made in an earlier post), nonetheless it will never have seen the kind of complex filth we would bring with us. Purely selfishly we would want to be extremely cautious about what we set in motion on a new world, and scientifically we would be foolish to be anything but careful, since Mars could hold keys to understanding our origins.

It has often been said that one of the motivations for finding life elsewhere in the universe is to increase our sample size – which is currently one. Extinct or extant organisms on Mars, whether related to us already or not, would offer a vital clue to the origins of life in this little corner of the cosmos. It would be truly awful irony if the first thing we did in transcending our planet-bound evolutionary path was to destroy the very evidence that would tell us where were came from in the first place.

So, SpaceX, what you’re doing is wonderful and exciting, and potentially critical for our species, just please, please tread softly.

The future on Mars? (SpaceX)


Caleb A. Scharf About the Author: Caleb Scharf is the director of Columbia University's multidisciplinary Astrobiology Center. He has worked in the fields of observational cosmology, X-ray astronomy, and more recently exoplanetary science. His books include Gravity's Engines (2012) and The Copernicus Complex (2014) (both from Scientific American / Farrar, Straus and Giroux.) Follow on Twitter @caleb_scharf.

The views expressed are those of the author and are not necessarily those of Scientific American.

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  1. 1. quickc 10:33 pm 02/13/2012

    In 2013, SpaceX plans to launch its Falcon Heavy launch vehicle. This launcher can send a Dragon capsule all the way to the surface of Mars and will cost 1/2 the cost of a less-capable Delta IV or Atlas 5. SpaceX will conduct the first launch on its own dime, but later launches will be paid for by the customer. If SpaceX is bold they may try to send their Dragon to the moon or even Mars if they want bragging rights as the first company to do so.

    Regardless, in short order, NASA can purchase a trip to Mars and a landing craft for pennies on the normal NASA dollar. The MARS program need not falter, just transform itself to take advantage of new space economies that private enterprise will create.

    One thing that will not help, however, is complaining about the current budget environment. We need to learn how to be bold and do more with less, not complain that we have less and do nothing but gripe.

    Sure JWST and SLS are eating our shirts, but that’s just pork politics at it’s best and there’s no stopping it by force (embarrassment at the achievements of commercial space, on the otherhand may be our best bet for seeing at least the SLS die away).

    Besides, we need to get away from all this entitlement thinking if we are ever going to conquer space and learn the mysteries of the universe. The money always belonged to the taxpayer and was not the right of science to take anyway. If the taxpayers elect leaders who wish to waste money that’s their perogative.

    We should be trying to use our public funding better and finding sources other than public funding as well.

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  2. 2. caleb_scharf 8:26 am 02/14/2012

    I certainly think we’ve reached a point of change. The trick will be for NASA to transform into something more agile. As an agency it has truly remarkable personnel to draw upon, with engineering and scientific talent coming out of its ears (really, it does. I spent a few years at a NASA center and it was an eye opener, you would not find more extraordinary people at the most elite university, but of course there was also deadwood). The next few years will be interesting for sure.

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  3. 3. Torbjörn Larsson, OM 2:58 pm 02/14/2012

    Of course it is worthwhile to try to colonize, and it will slightly lower risk for our species, but let us recognize that the risk isn’t large to begin with.

    Roughly estimated, our world has had a continued biosphere for ~ 4 billion years. Our ancestors H. erectus became ~ 2 million years old, respectable among mammals. Modern H. sapiens is ~ 0.2 million years, so we have at most ~ 2/4000 = 5*10^-4 risk of going extinct from external reasons before our time. That is not much compared to the longevity problems of earlier civilizations.

    I hear the minimum gene exchange between sexual subpopulations needed to keep them as one large is ~ 1 cross fertilization/generation, regardless of population size. So yes, we can likely keep an Earth/Mars species going. However, when we start to colonize the Oort clouds between stars, ‘our’ species will split and be ‘lost’ due to the distances involved.

    “It would be truly awful irony if the first thing we did in transcending our planet-bound evolutionary path was to destroy the very evidence that would tell us where were came from in the first place.”

    To have invasive species in our biosphere they need to be generalist and adapted to the overall environment. There is no way Earth species can compete with indigenous species.

    We are lucky Mars surface is sterilized by heavy oxidation, or we would need to use neutron bombs before building surface habitats. Seeing some or all habitats will likely be subsurface, there will be some risk involved – for us.

    We can always detect contamination or recent transpermia here. The problem for experiments detecting organics is to be clean enough when landing.

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  4. 4. caleb_scharf 6:00 pm 02/14/2012

    Thanks for comments. I’m not sure I agree that Earth species would be unable to compete with indigenous – given the overlap in martian and terrestrial (extreme) environments, and time and time again we find unexpected interactions between invasive species and native. Also, given that we have probably identified and sequenced only a tiny fraction of Earth species (i.e. including microbial life) I think that dumping loads of these on Mars would make the task of finding/identifying true martian species (even if very different) vastly more difficult than it would otherwise be.

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