If there’s one idea that will never die it’s that of turning one of our sister planets into a habitable world to call our own. My head has been filled with the possibilities thanks mostly to me finally sitting down to watch Cowboy Bebopafter being told to do so for almost 10 years. However long before I discovered my passion for space exploration I’ve always wondered about the possibility of transforming a world into the lush paradise that we now call Earth. It may surprise you to learn that the science of terraforming a world is quite solid, although it does require feats of engineering on the scales the likes of which we have never seen. Still over the past couple years I’ve developed a theory about how we could go about terraforming one of our sister planets, Mars, into a lively vibrant world.
Mars was once a place not too unlike earth. Studies have shown that vast oceans once covered a great deal of the planet’s surface and that it had an atmosphere much thicker than the one it has today. However Mars is much smaller than our earth and is also quite a distance further away from the sun. Consequently Mars’ atmosphere was stripped away by solar winds and the core of the planet cooled very quickly further accelerating the planet’s geological death. Today all that remains are vast deserts of rust and a tenuous layer of carbon dioxide but that doesn’t mean the planet is beyond saving.
Now whilst Mars wasn’t able to hold onto its original atmosphere that doesn’t mean it isn’t capable of doing so. On a human timescale the atmospheric loss due to solar wind erosion would be quite minimal on the order of 100 tons per day. When the total mass required to give Mars a livable atmosphere is on the order of 7.2 x 1017Kgsuch a loss would take many millennia to have any effect. The issue is of course how we get such enormous amounts of matter up into the martian atmosphere, and this is where things start to get a little dreamy eyed.
In my view comets are the answer to this question. Many of them are large balls of water ice with many other compounds and gasses trapped inside them. Additionally many of them are quite large in mass, on a similar order of magnitude to that of the gas required to make the martian atmosphere livable. Using a small space craft acting as a gravity tugwould allow us to steer some of the comets of our solar system on a collision course with that of Mars. The most optimal solution would be to get the comets into orbit around the red planet and slowly de-orbit them so that the majority of their composition ends up in the upper atmosphere however this requires a lot more energy to achieve. There is the possibility that some may already be on course for such a collision (like Phobos and Demios appear to have been) but the best hope to get such materials onto the planet is to smash it right into Mars.
Over time the materials would sublimate and begin replenishing the martian atmosphere. Eventually, with enough materials bombarding the planet, it would develop a climate and greenhouse effect. In order to ensure that the atmosphere was livable there would have to be a much higher amount of greenhouse gases to make sure that the reduced heat from the sun was more efficiently captured. Most comets contain decent amounts of methane which would help greatly with this process. Additionally the water ice from the comets would form the beginnings of large bodies of water which would be used to form the beginnings of an ecosphere.
One of the largest problems that the planet would face after this would be the intense amounts of radiation that Mars recieves. Whilst the new atmosphere would provide a bit of protection the vast majority would still get through. My solution would be in the form of small magnetic field generators to protect areas that will play host to the various seed lifeforms used to continue the terraforming. This is much more realistic than the proposition of restarting Mars’ core which requires unfathomable amounts of energy. Such generators could be powered by photovoltaics or small nuclear reactors with many of the raw materials being mined on site.
The next step is to seed the planet with simple forms of life which would be the building blocks for larger beings like ourselves. Many plants have shown incredible resilience to extreme environments like lichens and certain types of moss. Additionally the soil of Mars has shown to have ideal properties for growing fleshy plants such as asparagus which could form the basis of a sustainable on planet food source for an initial colony. In the more “tropical” parts of Mars it might even be possible to use something like Kudzu who’s less desirable properties here on earth make it a perfect candidate for creating a sustainable biosphere on the red planet.
Realistically such a process would likely take something on the order of centuries to complete as the various different stages would require some time to reach equilibrium. However each stage of the process is theoretically possible and some steps (like gravity tugging comets and local magnetic field generators) could be implemented with today’s technology. Mars makes a prime candidate because the environment there, whilst harsh, is quite a lot tamer than the other alternatives like Venus. Whilst I’m sure that something like this won’t get off the ground in our lifetimes I can already see the beginnings of the technology that makes this all possible and I know that one day, whether by desire or necessity, humanity will attempt this mega engineering feat.
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