In recent times well known figures such as Elon Musk (of Spacex) and the late Prof. Stephen Hawking have made highly publicised comments about space exploration and the necessity for humanity to colonise other planets (such as Mars) in order to ensure human survival in the future.
While such luminaries may well be right in suggesting that humanity is more than able to bring about its own destruction, I do not believe that attempting to populate other environments is the solution to the problem of human survival. Apart from the great challenges that face those attempting such a feat, the fundamental problems of human behaviour are still likely to apply in any locations additional to our own planet.
Before looking at humanity’s innate problems and our struggle to overcome them, let us consider the immensity of any attempt to colonize the Moon or a nearby planet such as Mars. The Moon is much closer to Earth than Mars (240,000 miles as opposed to at least 35 million miles) so it would obviously be easier to try a settlement closer to home first.
Despite its relatively convenient location, the Moon offers much greater challenges than Mars in many respects. For starters the gravity on the Moon is only about 17% of that on Earth, whereas on Mars it’s not far off 40% of that on Earth. The effects of long-term exposure to low gravity are quite serious with loss of bone mass (like osteoporosis), muscle wasting, deterioration of liver function and possible damage to eyesight. So far, the longest anyone has spent in space is 438 days, so it is hard to gauge the negative effects of spending several years or decades in a low gravity situation. Long-term existence in low gravity would undoubtedly make returning to Earth difficult or even impossible and there might also be implications for life expectancy for continual living in a low gravity environment.
Temperature is a significant problem for any would-be colonists, particularly on the Moon, which has no atmosphere. Daytime periods, which last for approximately half of the 28 day lunar cycle, can see surface temperatures of over 120 Celsius. For the other half of the cycle the surface is plunged into darkness and temperatures of around -150 Celsius. Obviously prolonged periods of extreme cold (and darkness) or extreme heat would make creating a stable environment for humans very difficult. Assuming that it could be done, one would still need to provide an environment that is suitable for growing food – with no water, no atmosphere and extended periods of cold and darkness it does not look very feasible.
The situation on Mars does not look quite so bleak, despite the fact that it would currently take at least 150 days to get there. In the Martian summer temperatures at the equator can reach an encouraging 20 Celsius, although generally temperatures only make it above freezing for a very short portion of the year (of 687 days). At night temperatures can plummet to -100 Celsius, even in summer, due to the thinness of the atmosphere. Mercifully the nights are similar in duration to those on Earth as the Martian day is marginally more than on earth and the axis tilt is only 2 degrees higher. Although this is a lot more inviting than the Moon, average temperature is around -55 Celsius and daytime temperatures rarely creep above the freezing point of water.
All this makes creating a human environment difficult, especially given that the Martian year is nearly twice as long as here on Earth and combined with its off-centre elliptical orbit, severely low temperatures outside of summer can be very long lasting. If it’s going to be difficult to keep warm for humans, that could be a more dramatic problem for plant life which we would need to cultivate to feed us. Plants need exposure to sunlight in order to stay alive and so would need to be grown in some kind of greenhouse type structure in order to allow heat and light to reach them. This would not be so great at night unless some form of effective insulation could be provided to stop the contents of the ‘greenhouse’ from freezing.
For any long-term situation on Mars it would be essential for humans to be able to grow their own food. The atmosphere is 96% carbon dioxide on Mars which is fine for plants but deadly for humans. Unfortunately, like us, plants need oxygen (albeit a tiny amount), which is sadly lacking on Mars. Apart from the surface being too cold for plants the air pressure is about 100 times lower than on earth, what affect that would have is unknown. Assuming there are no pathogens in the air, external carbon dioxide could be brought into the closed environment but oxygen would need to be brought from earth or extracted from the frozen polar ice. If this could be done and similar air pressure to earth created, in time it should be possible for plants to create a stable ecosystem that provides sufficient oxygen for a human colony although many hundreds of plants or huge amounts of algae would be needed to provide for just one person.
Initially oxygen would have to be brought to the colony or obtained from water by splitting the oxygen from hydrogen and this would not be easy as water is known to exist at the frozen poles.
Growing plants for food and oxygen would be essential for any colony however it’s not going to be simple. Plants would need light but they would also need to be protected from harmful rays (by filters) that penetrate the thin Martian atmosphere. Plants need a growing medium, usually soil, and nutrients but both are rather lacking on Mars. There is no organic soil on Mars, it’s more like sand and although many of the right minerals do exist there, the proportions are tiny compared to what is typical on Earth – artificial fertilizers would be needed.
The soil on Mars is so thin and dry that a huge amount of it ends up as dust in the atmosphere. With rapid temperature changes a great deal of wind is generated, with maximum speeds of around 60mph. Dust storms would be a major problem to overcome on Mars as, on occasion, they engulf almost the whole planet and can last for weeks or even months at a time. High levels of dust in the atmosphere decrease light and heat penetration, just like a volcanic eruption can on Earth. On Earth such incidents are usually localized and short-lived. Severe eruptions in our past caused crop failure and famines on Earth; imagine how a dust storm of months on Mars could impact solar energy production and the photosynthesis of plants.
One particularly important component for survival, that I have barely mentioned yet, is water. The Moon has no water, but there is some present on Mars – in tiny amounts in the atmosphere and as ice at the poles. It would not be possible to transport sufficient water to another planet to provide for a colony so it would need to be separated from any frozen carbon dioxide at the poles and brought to the colony and melted. In the nineteenth century, before refrigeration was invented, huge blocks of ice were transported mostly by ship from northerly regions and sold where-ever people could afford to buy it. So, in theory, ice could be transported from polar regions on Mars to a colony (presumably near the warmer equator) but the logistics of long-distance transportation on a planet with no breathable atmosphere and severe dust storms would not be easy to overcome.
All that I have mentioned so far are just the basic problems of establishing even a tiny community on another world. Assuming that all of the huge problems of creating a workable environment could be overcome we have made no allowance for the inevitable complexities of human existence. Apart from the input of energy of the sun, we live in essentially a closed system that can provide everything that humanity needs to live. We do not need to find, bring or manufacture air, soil, water, plant and animal life in order to survive as it is already here.
Despite having the good fortune to exist on a planet that can provide perfectly for our needs humanity has had and continues to have great difficulty in living in a sustainable way. Humans have an unfortunate tendency to over-consume resources, damage life-sustaining parts of the environment (water, air, soil, other species) and also compete violently with each other and other life forms. In the past we have found that the easiest solution to our problems was to move somewhere else that had not been fully exploited. A small number of isolated communities do continue to live in a sustainable way, but they are under threat from the proliferation of destructive modern living patterns.
Until fairly recently the world seemed like a huge place, inexhaustible and indestructible. However, with a world population of close to 8 billion people and increasing demand for finite resources we are all becoming aware of the dire impact humanity is having on our planet. Of course, the possibility of our destruction is one of the main justifications for attempting to colonize somewhere else.
If we had another Earth to migrate to, it might seem justifiable to move there and start again, although it would not necessarily change the way that we behave – in fact the sudden lack of need to change our ways might ensure that it would not happen. The fact is that we do not have another Earth and trying to create a long-term livable environment somewhere else could prove to be impossible.
Even if it were possible to create a colony on Mars in the decades to come, how many people could it sustain? Without a constant influx of resources to expand a colony of say 100 people, a tiny speck of humanity would be sustainable. The scale of creating a Martian colony of a million people (which is a tiny fraction of humanity) is so daunting that it really is in the realms of science-fiction. Even if such a colony were possible, how would we overcome the continued human tendencies of over-populating, degrading our environment and fighting amongst ourselves? Such behaviour is dangerous for humanity and the world here on Earth, one can only imagine how dangerous it would be for a community in a highly restricted and vulnerable alien environment.
Despite all of the damage that we have done to the planet, which we are only beginning to understand now, we still live on a beautiful and habitable world. Running away to another planet is not going solve the problems of humanity as our fundamental problem is not of technology or resources but of our behaviour. If we insist on trying to colonize Mars or anywhere else we are liable to run into the same problems, created by our behaviour patterns, including our chronic problem of military conflict that shows no sign of ending.
While we are learning that we need to change and learning new and better ways of doing things we still have a very long way to go. What knowledge, energy and resources we have should be concentrated on solving the problems of living here, on this planet that is ideally suited to us. The thought of being stuck here if we do manage to fatally damage Earth is rather terrifying, but perhaps a lack of other viable options might be what saves us. Scientific exploration and expansion of our understanding of the universe is a benefit to humanity, but it should not be used to offer false hope to a species that could be faced with self annihilation. With the possibility of escaping to somewhere else removed we are left with only one realistic option – finding a way out of the mess we have created.
The huge amount of money, time, energy and physical resources that is allocated for or currently being used for space exploration and colonization would be better expended on dealing with the plethora of problems that exist on Earth. We do not yet have the technology to make colonizing Mars or other places a reality, but we do have the technology to fix our problems here on Earth.
The know-how for producing renewable energy has been around for decades and the technology has improved with more and better techniques coming on line in recent years. Nuclear energy is dangerous, potentially explosive and produces huge amounts of radioactive waste – a problem that could haunt us for centuries. This is just one problem that humanity has failed to address properly and is long overdue being solved for the good of future generations. The technology for solving this and much of the pollution problems, including plastic waste, already exists but is very expensive at the moment.
Much of the world’s problems such as environmental degradation, over population and poor resource distribution, economic and physical warfare can be changed simply by changing how we think and do things and don’t necessarily need advanced technology – just the will to do it and allocation of resources. Humanity’s problems are not problems of technology they are behavioral and that is down to our failure to mature as a species. While we continue to put conflict, greed, self-interest and short-term goals above cooperation, consideration and the long-term future of all life, running away to another planet is not going to save us.
You can read more of Luke’s work at lukeeastwood.com.