As soon as people realized how unsuitable for life Mars, Venus, and indeed the entire solar system, they wanted to figure out how to fix it. There is a special word for working on a planet to make it more like Earth: terraforming.
If you want to tweak Mars, all you have to do is thicken the atmosphere and heat it up to the point where terrestrial organisms can survive there. With Venus, you need to do the opposite - cool down and reduce the atmospheric pressure.
But it is very difficult to understand the scale of such an event. We're talking about trying to change an inconceivably huge atmospheric volume. The atmospheric pressure on the surface of Venus is 90 times higher than the pressure on Earth. This is carbon dioxide, so you need some chemicals to get rid of it, like magnesium or calcium. If you can mine four times the mass of asteroid West, then it will be possible.
Meanwhile, over the past several thousand years, we have played an active role in the evolution of the cultivated plants and domestic animals that we eat and care for. Our dog pets look completely different from the wolf ancestor from which they descended. We've increased corn and wheat yields, modified fruits and vegetables, and turned chickens into self-propelled, self-propelled breasts that cannot fly.
And in the past few decades, we have received a new and most powerful tool for changing life to our needs: genetic modification. Instead of waiting for evolutionary changes and breeding in order to obtain the desired results, we can rewrite the genetic codes of different life forms, borrow the positive properties of one species and insert them into the code of another species.
Can we adapt terrestrial life to the conditions on Mars? It turns out that our most resilient organisms are not that far from it. During a 2015 meeting of the American Society for Microbiology, researchers demonstrated how well resilient bacteria can feel in Martian conditions. They found that four types of methanogens may be able to survive below the surface by consuming hydrogen and carbon dioxide and releasing methane.
In other words, under certain conditions, some terrestrial life forms can survive on Mars now. In fact, in the process of exploring Mars, we realized that it is wetter than previously thought, so we risk inadvertently infecting the planet with our own microbes.
But when we imagine life on Mars, we are not thinking of a handful of resilient metagens fighting for life under the salty regolith. No, we imagine plants, trees and animals scurrying around.
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Do we have something like this that we could modify?
It turns out that the formations of lichens, symbiotic combinations of fungi and algae, have a chance. You may have seen lichens on rocks and elsewhere that are not suitable for all other life forms. And according to Jean-Pierre de Vera and the Institute for Planetary Research at the German Aerospace Center in Berlin, there are terrestrial lichens that are resilient enough for this.
They placed the lichen in an experimental environment that mimicked the surface of Mars: low pressure, carbon dioxide atmosphere, severe frosts and high radiation. The only things they could not reproduce were galactic radiation and low gravity.
In the harshest conditions, the lichen barely survived, clinging to life with difficulty. But in a milder version of Martian conditions, hiding in rocky crevices, the lichen continued to carry out its usual photosynthesis.
It seems that the lichen is also ready to go to Mars.
Methanogens and resistant lichen are, of course, not quite the same as a beautiful shady forest. Secondly, I'm going to talk about what we can do to tweak earthly life forms to exist and thrive on Mars. But first of all, I would like to thank Zach Kanzler, Jeremy Payne, James Craver, Mike Janzen and all of our other 709 sponsors for their generous support. If you like what we do and want to help, check out here.
If the existing earthly life does not cope with the work, well, we just need to adapt ourselves. Just as we have done in the past, using selection, and in a more modern way - by correcting the DNA itself.
Unless we make drastic changes to the Martian environment to thicken Mars' atmosphere and raise temperatures, it’s unthinkable that we will ever be able to adapt anything more complex than bacteria or lichens to survive on Mars. But if they create a base for us, and other technologies help improve the state of the environment, it will become possible to gradually move in the right direction.
Even in protected areas within the Martian colonies, our current plants and animals are unlikely to be up to the task.
The regolith of Mars, for example, contains poisonous perchlorates that would kill any terrestrial plants that dared to take root there. But there are life forms on earth that adore perchlorates and are likely to actually create organisms that will pull poisonous substances from the regolith and turn them into something useful, like rocket fuel.
Terrestrial plants and animals live according to a 24-hour day cycle, but on Mars a day is 40 minutes longer than on Earth. We can grow plants under artificial light, but if we want to use natural Martian light, it is possible that some adaptation will be required.
Perhaps the biggest risk we will face living on Mars is lower gravity. It is not known whether life at 38% of the Earth's gravity will be good for us, generation after generation. We know that we can stay on Mars for several years, but can a pregnancy, for example, complete a full cycle with such a low force of attraction?
We just don't know. To find out safely, we have to create a rotating space station and settle colonies there, so we can change gravity and see what happens to animals that have lived in low gravity for several generations.
If health problems arise, we can rely on the results of these studies and modify the genetic code to better adapt to these conditions. And since people are also animals, the experience gained will help us to adapt and be more prepared for survival on Mars, forever.
Here is a link to Kurzgesagt's marvelous video on the state of genetic engineering and impressive technology just around the corner.
If we can change humans for life on Mars, we can probably do so for other worlds. Imagine a distant future where human colonies live in different worlds, adapting to survive there, combining technology and genetic modification.
It will be both good and bad. The good news is that human colonies can survive for generations. And it's bad that they won't be able to live anywhere else in the solar system without going through the whole process of adaptation again.
Would you like to permanently change your body in order to better adapt to life in another world? Write what you think about this in the comments.