We are obsessed with Mars . Not only thanks to the tireless enthusiasm of people like Elon Musk , whose life and work seems to revolve around the goal of sending humans to live on Mars , or movies and video games like Mars (The Martian), Doom or Red Faction. In the 90s we were already obsessed, as Babylon 5, Total Challenge or Mars attack demonstrate, and even more than a century ago, when HG Wells ‘ War of the Worlds or Thomas Edison ‘s A Trip to Mars were created.
Today we have abandoned the ideas we had about invaders and intelligent Martian life but not the desire to visit the red planet . In recent years, several space agencies have redoubled their efforts and proposed specific dates for the arrival of the first humans on Mars . Companies like SpaceX , whose main and ultimate goal is to create a self-sufficient colony on Mars, are also developing reusable rockets and new technologies to make this process cheaper and faster. But why? Why Mars and not another planet or moon?
Our moon is almost a thousand times closer than Mars , so it is much easier to maintain a human colony there and, above all, to supply it. Venus is half to half the distance from Mars and has a gravity more like ours. Even some moons like Europa or Enceladus , which orbit Jupiter and Saturn respectively, we think have oceans of water several kilometers deep surrounding their inner layers.
So what attracts us so much to the red planet? Why do all our efforts seem to be geared in that direction? Other than Earth, no other body in the solar system has the ideal conditions to host a human colony . None have a breathable atmosphere and some do not even have an atmosphere or liquid water on their surface. They also do not have the range of temperatures that we are used to.
Despite all this, there are certainly some better options than others . For example, the Moon is the most comfortable destination due to its proximity and, of course, we intend to create bases on it where astronauts can live and investigate. But the possibility of a permanent and self-sufficient colony is complicated, mainly because our satellite does not have an atmosphere , so it does not have the natural protection that an atmosphere offers against small meteorites or certain radiation. In addition , building is more complicated due to the constant pressure difference between the interior and exterior of the cabins. One of the most important resources for any human colony is scarce on the Moon: water. Although oxygen is very abundant, it is found forming oxides together with other elements in a way that is complicated and expensive to process.
Venus would be a real hell . The average temperature of the planet is more than 460 ºC . At this temperature materials such as tin and lead melt in a matter of minutes. In addition, the atmospheric pressure on the surface of Venus is about 90 times that of Earth, equivalent to the pressure almost 1 km deep in the sea. Both conditions are a consequence of its dense atmosphere , made up of 96% carbon dioxide, a gas that is very efficient at trapping heat and warming atmospheres.
Europa, Enceladus and other bodies beyond Mars have precisely the opposite problem. They are too cold . Although Europa we think contains twice the amount of liquid water that we have here on Earth, that water is under a layer of at least 10 kilometers of ice.
Well, Mars , which is far from ideal, does not have these problems but it does have others . The average temperature on the Martian surface is about -63 ºC , cool but remediable with appropriate materials. Its atmosphere is 100 times less dense than Earth’s and it is not enough to provide complete protection against solar radiation, but it is certainly better than not having it or having something that looks more like an ocean. This atmosphere can be used for wind power , something impossible on the Moon. Relatively clear skies, except during dust storms, and a day/night cycle of less than 25 hours would also allow for solar power.
Even if wind and solar power weren’t enough, Mars could still have an advantage . If we manage to develop nuclear fusion as a source of energy , Mars has about five times more deuterium (an excellent fuel) than Earth and thousands of times more than the Moon. However, everything indicates that we will reach Mars before a stable and efficient nuclear fusion. In addition, Mars has practically all the elements that we may need in our technological development in a more accessible way.
As if these reasons weren’t already enough, Mars is believed to be the easiest planet to terraform. Terraforming involves transforming the atmosphere and surface of a planet to make it habitable for humans. There are many proposals on how to do it, the main objective of all of them being to create a Martian global warming to increase the thickness of its atmosphere. Most are relatively conservative , such as heating and melting the poles using orbiting mirrors, creating an artificial magnetosphere by placing magnets in space that protect the atmosphere from erosion by the solar wind, or colliding gas-rich asteroids. greenhouse effect and increase the amount of gas in the atmosphere and also its temperature. But there are also other proposals that are more drastic , such as that of Elon Musk, to drop nuclear bombs on the polar ice caps to melt them. If it is finally done, the terraforming of Mars will be a process that lasts at least hundreds of years. Meanwhile, the humans who inhabit the red planet will have to do so indoors or with space suits and on a surface and soil that, right now, are inhospitable to terrestrial life.
In short, we are obsessed with Mars because it is the least bad of many terrible options.
