Image Description: Surface of the planet Mars.
By John Fegebank
For better or for worse, humanity has manipulated, rearranged, and altered its environment for millennia to suit its needs. It is this proficiency that has allowed us to dominate the planet as a species. In fact, we have gotten so good at this, that we are capable of changing our planet on a global scale, even changing how other species evolve. As our technology further progresses, it truly seems that our capabilities are unlimited in this manner. What challenge could possibly face us that we won’t overcome?
Already we are pushing the limits of our abilities, trying to venture from our ancestral planet into the great unknown; specifically looking to our red neighbour, Mars. But there is one slight problem — as it is, Mars is uninhabitable for humans. If we intend to live there permanently, we will have to do to radically change Mars’ environment beyond anything we’ve ever done before.
Though it may seem like a dull rock floating through space, it is important to not overlook what specifically makes Mars special.
As early as the nineteenth century, humans have noticed peculiar channels on the Martian surface. But such channels don’t just form by themselves; they are shaped by something over long periods of time, something we have an abundance of here on Earth — liquid water. This raises the question, then, that if there was once water on Mars, where did it all go?
The answer is rather simple; it probably went into space. You see, modern Mars has a very thin atmosphere unable to provide the right conditions of pressure and temperature for water to remain in its liquid state, so the vast majority will boil away, leaving the red planet barren. However, a small amount in the colder regions of the planet (mainly its poles) will instead freeze into ice, hence why Mars has polar ice caps. What this all then implies is twofold; that Mars once had a vastly different environment which could have been habitable, and that Mars’ atmosphere is the first major barrier we face to making it habitable for ourselves – in other words, terraforming.
With the latter in mind, our first step would be to essentially replace the lost atmosphere, preferably with something we can tolerate. The next big issue is that it is very, very cold on Mars. The average temperature there is about negative 63° Celsius, and compared to Earth’s relatively balmy average of 14° Celsius, it becomes very easy to see why people wanting to live on Mars would probably have a hard time not freezing to death.
Fortunately for us, we have a way of theoretically fixing both of those issues. You’re probably familiar with the greenhouse effect, where certain gasses in the atmosphere trap heat around the planet and keep it warm. It’s something that’s proving to be quite detrimental to us, and also something we’re responsible for. What you may not have heard of is the ‘runaway greenhouse effect’; it is essentially the same principle, except that once the temperature rises a few degrees, it causes various pockets of these atmospheric gasses to be released from the surface of the planet into the atmosphere. In turn, this extra gas heats the planet further, which releases even more gas, which will eventually result in a much warmer atmosphere. It’s actually believed that this may have happened to Venus at one point, turning it into the hottest planet in our solar system. Luckily, we know there are such pockets on Mars as well, so in theory, if we were able to heat the planet just enough, we might be able to create this effect and bring the Martian temperatures up to a more comfortable level.
Unfortunately, there is one major problem that puts a wrench in all that. You see, back when Mars had a much thicker atmosphere, it was also believed to have something to help protect it; a ‘magnetosphere’, which is the magnetic field produced by a planet’s core. It’s most important life-sustaining feature is that it blocks most of the harmful radiation of the sun from hitting the planet. We’re not exactly sure why, but at some point, Mars’ field weakened significantly, and the sun’s radiation stripped its then unprotected atmosphere, making it into the barren landscape it is today. As far as we can tell, with the water and carbon dioxide content we’ve found on Mars, it just wouldn’t suffice for the rate it’d be lost at. Unless we can figure out a way to kick start it’s magnetosphere again, all other attempts to make the Martian surface habitable for us would be futile.
Either way, there still remains the eternal struggle between ‘could’ and ‘should’ that is a part of every journey in science. Based on data from a subsurface radar on Mars, there is believed to be at least one large lake below the surface, which is likely full of salts that are keeping it from freezing. That means there may be many more hidden bodies of water beneath Mars’ surface, which may house some forms of microbial or even larger lifeforms. Now, this is mere speculation, but it would not be out of the realm of possibility that entire alien ecosystems could have been living there for millions of years, all the while unbeknownst to us. Perhaps then we should be asking ourselves, not could we terraform Mars, but should we? We’ve seen how humanity, especially in our current mode of production, decimates ecosystems; how could we ensure we don’t do that to Mars, lest there be life there too?
Humanity has always had a special talent for bending the environment around it to suit its needs. We’re an ambitious bunch that are always looking for new places to set ourselves up. As we move beyond our pale blue dot, the challenges we will face in continuing this trend will be enormous, and so will the changes we will need to bring just for our frail human bodies to survive in these foreign environments.
All of this hinges on technology yet unavailable to us, so it will still be plenty of time until we can even attempt something like this, let alone successfully. Until then, as we wait with the self-awareness of our actions and their consequences, we should consider those species that may lay in our paths.
The only thing stronger than John’s love of physics is his caffeine addiction.
Image courtesy of Pixabay