Good luck, and beware of the bears - on Carl Sagan, and human settlement on Mars and Venus

Earthing Mars and Venus will change the surface of these planets, but also humanity

Once upon a time, many years ago, before the Internet, before the second channel, maybe even before the dinosaurs... there was the first channel. And in those days, science had a face and it also had a voice.

The face and voice belonged to Carl Sagan whose television series, 'Cosmos', was broadcast as part of the educational television broadcasts on Channel One. As a small child, I sat mesmerized in front of the screen as Sagan took me on journeys through the universe and inside the human body. I still remember the episode that dealt with the human mind: Sagan stood in a long corridor whose walls were covered with drawers, and explained that each drawer was a cell that contained memories from the past. Sagan spoke, and all I could think about was - 'Open one! Let's see what's inside!' I didn't understand why he was opening the drawers. I didn't know the concept of 'setting' yet, at the time.

Carl Edward Sagan was born in the United States in 1934, to a Reform Jewish family. He fell in love with everything related to space and the stars when he was in elementary school, and his curiosity about the universe around us was insatiable. As he grew up he studied physics and astronomy, completing his doctorate in 1960.
In those days, the fifties and sixties, the planet Venus was the focus of astronomers' interest. Venus was an intriguing mystery. His face was covered with a perpetual layer of clouds that hid the surface, and no one could tell what was beneath them. Already in the nineteenth century, there were astronomers who speculated that the thick clouds of Venus were constantly raining, and that life might have developed on it. Science fiction writers imagined a world-wide tropical jungle and swamps teeming with alien life... Sagan was convinced, even as a child, that there was other life in the universe. It is not surprising, however, that his first important scientific study dealt with this planet.

But when Sagan examined the results of radio wave measurements received from Venus, he began to suspect that conditions on the surface were very different than everyone thought. Additional astronomical measurements, this time of the proportion of carbon dioxide in the atmosphere of Venus, strengthened this feeling for him.

It is likely that most of you have heard of the term 'greenhouse effect' in connection with the danger of global warming of the earth. Even if you haven't heard of it, you must have experienced it firsthand every time you left your car in the sun for several hours: the temperature in the closed car may reach sixty or even seventy degrees Celsius, while the temperature outside the car - even on a hot summer day - is much lower. why?

The sun emits different types of radiation, including the light we can see. The visible light passes through the clear glass of the car without difficulty, heating the dashboard and the upholstery inside. This heating causes the surfaces to emit radiation themselves, but in a frequency range lower than that of visible light: infrared radiation, or in its foreign name 'infra red'. The glass is transparent to visible light but opaque to infrared radiation, therefore it 'imprisons' the infrared radiation inside the vehicle, allowing it to heat the interior surfaces even more. The heating causes an increased emission of infrared radiation, which in turn heats the surfaces even more - and so on and so forth. This cyclical process is the 'greenhouse effect', a name borrowed from the common use of this phenomenon in agricultural greenhouses.

The same phenomenon also occurs in the atmosphere. Certain gases, including carbon dioxide, function like the glass in the previous example: the visible light passes through them without difficulty and heats the ground and it emits infrared radiation. The carbon dioxide captures the infrared radiation and does not allow it to escape back into outer space, thus causing the atmosphere to heat up - as if someone had spread a blanket around the entire earth.

Carl Sagan knew that here on Earth, the greenhouse effect helps maintain a comfortable temperature of ten to twenty degrees Celsius on average. On the other hand, the proportion of carbon dioxide in our atmosphere is less than one percent, while on Venus, the measurements showed, it is over ninety percent. Sagan's calculations suggested that the greenhouse effect on Venus would raise the temperature on its surface to more than 300 degrees Celsius, or in other words - the surface of Venus is not covered in swamps, but in a hot and dry desert.
Sagan published his theory in 1961, in Science magazine: the article aroused great interest and was praised. But hypotheses and theoretical calculations are one thing, and facts in the field are another. Sagan had no real evidence for his hypotheses, and he understood very well that if it turned out that the temperature on Venus's face was much lower than her hair - the compliments would quickly turn into ridicule and embarrassment.

Sagan did not have to endure the uncertainty for long.

The mystery surrounding Venus was one of the reasons why both the Americans and the Russians decided to send their first research spacecraft to it, in the XNUMXs. As with everything related to the space program, here too there was intense competition between the two superpowers.

The Russians were the first to launch a spacecraft to Venus, in 1961. The Venera 1VA spacecraft was equipped with a variety of measuring devices, and also a small souvenir from Earth: a metal ball in the shape of a globe, with the symbol of the Soviet Union on it. Unfortunately, a technical malfunction in the rocket carrying Venera 1VA failed the launch, and the spacecraft crashed back to Earth. Soviet engineers were convinced that Schooner 1VA had fallen into the Pacific Ocean. Two years later a local boy was swimming in a river in eastern Siberia, and stepped on a piece of metal. He picked it up, and saw that it was a metal ball with strange markings on it. The boy's father passed the metal ball to the KGB, and from there the souvenir found its way to the Soviet Space Agency. Only then did the engineers discover, for the first time, that their spaceship had crashed in Siberia, and not in the Pacific Ocean. This strange story raises an interesting question: who is more durable - a metal ball that survived a crash from a great height, or a boy who is ready to swim in the frozen rivers of Eastern Siberia.

The second spacecraft launched by the Soviet Union to Venus also failed in its mission: it came very close to Venus, but failed to return data and measurements. This failure allowed the Americans to take the lead: their spacecraft, Mariner 2, passed by Venus and sent the first data. The measurements were unequivocal: the temperature of the atmosphere of Venus ranges between 420 and 500 degrees Celsius, hot enough to turn a lump of lead into a metallic puddle... These findings confirmed Sagan's hypotheses, and the successful prediction - combined with the natural charisma he possessed - catapulted him into the consciousness of the general public , and were the first step on the way to a very successful career. He wrote popular science and science fiction books, and the television series he hosted were widely praised. The saying most associated with Sagan is 'billions upon billions', which he used to illustrate how many stars there are in the universe. He tended to repeat it from time to time…

Carl Sagan, as mentioned, believed with all his heart that there are other living beings in the universe. Not many know, however, that Sagan was also the first scientist to seriously consider the possibility of the 'Earth' (in 'A') of another planet.

'Terraforming' (in English) is changing a planet or some kind of moon, with the aim of creating conditions on it that are more similar to those on Earth that will allow humans to settle on it one day. The idea appeared in science fiction many years before Sagan, but was never seriously considered: after all, these were the days before satellites and manned spacecraft. But Sagan, and other scientists after him, knew that colonizing another planet is a goal we must strive for.

It's no secret that the world's population is growing year by year, and the Earth is becoming more densely populated. However, the purpose of earthing is not to alleviate this overcrowding by transferring a significant portion of the existing population to another planet. It is much easier, from a practical point of view, to develop uninhabited areas on Earth such as Siberia or the Sahara desert, than to change the properties of another planet. The motivation behind the idea of ​​nationalization is the creation of a 'backup copy' for the human race. The population explosion puts a heavy strain on Earth's resources, and if we don't find a way to spread to other planets in the universe, it will only be a matter of time before we reach the limit of our world's ability to support such a large amount of humans. And if resource pollution and their exploitation do not harm us, then there is always the chance that an errant asteroid will hit the Earth and do to us what its predecessor did to the dinosaurs. Most of us are too engrossed in day-to-day problems to give much thought to events that will take place, if at all, in thousands of years, but scientists, especially in the field of astronomy and astrophysics, are used to thinking in terms of millions and even billions of years. They understand that the threat to the future of humanity, in the long term, is more tangible than we think.

In 1961, in the same paper in which he revealed his theory about the temperature on the surface of Venus, Sagan proposed spreading bacteria in the atmosphere of Venus so that they would convert the carbon dioxide into solid organic compounds and thus 'remove' it from the atmosphere. When the percentage of carbon dioxide in the atmosphere decreases, the greenhouse effect will also weaken and the temperature on the surface of the planet will drop to a level that will allow the existence of liquid water in particular, and life in general. Sagan knew, of course, that this was a process that would last thousands and perhaps hundreds of thousands of years - but already in those days he was intimately involved in the American space program as a scientific advisor, and knew that this was within the reach of existing technology.

But before the dispersal of bacteria in the atmosphere of Venus could be seriously considered, scientists had to know precisely the composition of its gases. Sagan had to wait another six years until he got answers on this matter as well.

The Soviet Union failed in its attempt to be the first to reach Venus, but the race is not over yet.
In 1965, the Venera 3 spacecraft was launched, which was intended to be the first spacecraft to actually penetrate the atmosphere of Venus, and in fact the first to reach the atmosphere of any alien planet. Venera 3 spent almost two years in space, arrived at Venus - began diving into the atmosphere... but then a malfunction occurred in the spacecraft's communication system. The spacecraft continued to collect data, but stopped transmitting it to Earth! One can imagine how frustrated the people of the Soviet space program were: so close, yet so far...

All eyes were now on Venera 4, which left Earth in June 1967. Venera 4 was an improved version of the failed spacecraft that preceded it, and some of the problematic systems were redesigned. However, the Russian engineers still did not know what to expect when the spacecraft arrived at Venus: would it find swamps and lakes, as was previously thought, or perhaps a hot and dry desert, as Mariner 2's measurements suggested? It was more likely to assume that the temperature would be high, so the spacecraft was equipped with an innovative cooling system. But just to be sure, the Soviets developed a special lock made of sugar: if you land Venera 4 in a lake of water, the water will dissolve the sugar, the lock will open and the communication antennas will be able to transmit properly.

Venera 4 arrived at Venus five months later, and began entering the atmosphere. All the systems worked correctly, and the measuring devices they started transmitting data back to Earth at a "dizzying" rate of one bit per second.

The surprises were not long in coming. It turned out that the white and almost pastoral clouds of Venus are not water clouds: in fact, there is almost no water vapor in the atmosphere of Venus. The white clouds are made of tiny drops of sulfuric acid, known to some of us by its common name - 'battery acid'.
The second big surprise was the density of the air. Venera 4's parachutes were to open at an altitude of about twenty-six kilometers, where engineers expected to find atmospheric pressure high enough to slow the spacecraft's fall. In practice, however, the atmospheric pressure on Venus was much higher than expected: a hundred times that on Earth. The atmosphere of Venus is so dense that at ground level the air pressure is equivalent to the pressure that prevails at a depth of a kilometer below sea level here.

The high air pressure meant that Venera 4's parachutes were already deployed at an altitude of fifty-two kilometers, instead of twenty-six. The spacecraft hovered in the atmosphere for much longer than expected, and its batteries died long before it reached the surface. Not that it made much of a difference: Venera 4 was likely crushed under the enormous pressure many miles before it hit the ground. Later, the Soviet Union managed to land more spacecraft on the surface of Venus, and these even managed to send several pictures before being crushed under the heavy pressure.

Venera 4 was a resounding success that provided scientists with invaluable data about the conditions prevailing on Venus. At the same time, she also closed the door on the dreams of the land of this planet. No bacterium could survive more than a few seconds in such an atmosphere, and at the very least it has almost no water vapor which is necessary for the existence of earthly life. In addition, Venus has almost no magnetic field, and hence its surface is exposed to harmful cosmic radiation at levels much higher than those on Earth.

This does not mean that a Venus landing is impossible. Archimedes once said: 'Give me a suitable fulcrum, and I will lift the whole world.' In the same way, if we invest unlimited resources and inexhaustible budgets, it is likely that we will be able to overcome all difficulties in one way or another. For example, there are those who have suggested bombarding Venus with giant asteroids to blow a significant part of the atmosphere into space, or spreading thousands of kilometers of reflective sheets between it and the sun to block the sun's radiation and stop the greenhouse effect.

It is quite clear, however, that such ideas are not going to come true in the next decades or perhaps even centuries: the technology required to implement them is not in sight, and it is difficult to imagine a situation in which any government would agree to direct 'unlimited resources' to such an ambitious project. In other words, the dream of Venus land has almost completely disappeared.

It is interesting to note that the data returned by Venus 4 nevertheless left a small opening for the realization of the dream of colonizing Venus. There is a certain region in the atmosphere, a thin strip at a height of about fifty kilometers above the ground, where the air pressure is one atmosphere - like on Earth - and the temperature is only a few tens of degrees above zero. In such an environment, humans can exist with only minimal protection: air supply, and a suit against the acid rain. Moreover, the air we breathe is lighter than the normal atmosphere of Venus - so a balloon filled with our air will float in the atmosphere of Venus like a balloon filled with helium here on Earth. This fact may allow us, perhaps, one day, to establish 'floating colonies' on Venus: large, air-filled structures that will float in the compressed atmosphere. I don't think I'd want to live in a colony like that, personally, but I'm sure the view is amazing.

Venus, which everyone saw as a tropical and watery planet, was the natural candidate for human settlement. Mars, on the other hand, is generally considered a less attractive possibility: astronomical observations in the 19th century showed that it is a desert planet, dry and not particularly hospitable. But at the same time as the discoveries that made the dream of settling on Venus impossible, new discoveries were made that made Mars the leading candidate in this field.

Devon Island is a vast island: according to Wikipedia, Devon covers fifty-five thousand square kilometers, and is the twenty-seventh largest island in the world. The population of this large island is exactly... zero people. The reason for this is the fact that Devon lies in the far north of Canada, a little more than a thousand kilometers from the North Pole, in a climatic region known as the 'Polar Desert': although the temperature in Devon is below zero most of the year, it almost never rains or snows.

But if you come to Devon during the summer, you will be able to witness an unusual sight. In the center of the island, not far from the rim of a large and ancient crater, stands a small, round, white building - and on it flies a flag that does not belong to any country: three vertical stripes - red, green and blue. If you wait patiently, you will be able to see the door of the building open and a man come out... dressed in a space suit. Welcome to FMARS: Flashline Mars Arctic Research Station, or as it is unofficially called - the first human settlement on Mars.

The conditions prevailing on Mars are to a large extent the complete opposite of the conditions on Venus: instead of a compressed and boiling atmosphere, the red atmosphere is thin and cold.

Mars is a relatively small planet - its mass is only about a tenth of that of Earth, so its gravity is only one third of what exists here. This fact, combined with its very weak magnetic field, resulted in almost all of Mars' original atmosphere being evaporated into space over the years: the atmospheric pressure on the surface is six to ten millibars, compared to more than a thousand millibars at sea level on Earth. The minimum air pressure necessary for humans is 61.8 millibars: below this pressure, body fluids such as water in the lungs and saliva in the mouth already boil at body temperature, which is 37 degrees Celsius.

Like Venus, the atmosphere of Mars is mostly composed of carbon dioxide, but the gas is so thin that the greenhouse effect is almost imperceptible. As a result, the temperature changes on Mars between the equatorial region and the poles, between the hours of day and night and between the seasons are much sharper than those on Earth. For example, the temperature on the meridian equator may reach 27 degrees at midday, while at the poles it drops to 143 below zero. The average temperature on the surface of Mars is minus 55 degrees, compared to 14 degrees here.

This is also the reason why the FMARS research station was established in 2000 on the deserted island of Devon, so close to the North Pole. The conditions prevailing in Devon, and especially the area known as 'Haughton Crater', are probably the closest that can be reached on Earth, to the conditions prevailing on Mars. Except for the intense cold, the hard and dry soil of Devon is also very reminiscent of the images taken by the robots that will lift the surface of Mars.

Every year during the summer a group of volunteers comes to the research station and stays there for one to three months. Their goal is to simulate, as much as possible, life in a human colony on Mars: they are strict about water discipline, conduct scientific experiments, and leave the station building wearing only a space suit. Their daily schedule is coordinated with a day of 24 hours and forty minutes, similar to the length of the Mediterranean day. Even part of the radio communication with the 'outside world' is done with an artificial delay of twenty minutes between question and answer, to simulate the delay in communication between Earth and Mars. The only 'discounts' that the crew members receive are in matters related to safety: for example, when going out into the field, one of the crew is allowed to walk around without a spacesuit, and his job is to make sure that polar bears do not attack the researchers.

The FMARS station was established and is maintained by an organization called the Mars Society. About 4000 scientists, entrepreneurs and space enthusiasts from about 50 countries around the world are members of the Mars Society, who set themselves the goal of promoting the idea of ​​landing on Mars and human settlement there. They organize scientific conferences on the subject, raise donations and sponsorships for relevant research and also collaborate with NASA. The red-green-blue flag that flies on the roof of the research station is the unofficial flag of the state of Mars, as it stands. The colors symbolize the progress of the earthing process: from red and rusty soil to a green and blooming landscape.

Life at the FMARS station is not easy. Although the volunteers have a rich DVD library and a dart board, the food comes in tins, showers are rarely allowed and there is no real privacy to speak of, of course. This is a life that is very reminiscent of a long voyage in a small, crowded ship...and surrounded by bears.

And yet, everyone who participates in the project does so with joy. In fact, not far from the FMARS station there is another research station called HMP (Haughton Mars Project) where volunteers carry out a similar activity. There is also a desert research station in Utah, in the United States.

What brings the members of the Mars Society and the volunteers who spend long and arduous weeks in isolated research stations to invest time, money and effort to advance the land of Mars? It's easy to dismiss this question by saying that it's a bunch of talkative lunatics with a lot of free time - but that can't be the only reason, especially if we consider that there isn't a single similar organization pushing the initiative to land Venus.

The reason for this is related to findings and discoveries made regarding the geology and history of the Red Planet in the last forty years. The data returned by the spacecraft and robotic vehicles that visited Mars indicate that the conditions on Mars were once quite similar to those on Earth: the temperatures were comfortable and water flowed on the surface.

The evaporation of Mars' atmosphere resulted in a significant drop in its surface temperature, but paradoxically, precisely the intense cold may be the key to our ability to make Mars, one day, 'Earth compatible'.

The liquid water, as well as some of the gases remaining in the atmosphere, froze - and today scientists estimate that at the poles and under the surface there are huge deposits of ice and dry ice: millions of tons of water and carbon dioxide. If we find a way to melt them, the surface of Mars will be covered with lakes tens of meters deep, and the atmospheric pressure will rise to about a third of that on Earth. It is clear that in the long run the gravity of Mars will not allow it to hold onto this new atmosphere, and it will also evaporate into space - but it is likely that several hundred thousand years will pass before this happens.

The separation of the glaciers, as a first step on the way to the complete earthing of Mars, will not be a simple or cheap matter - but contrary to the proposals made regarding the earthing of Venus, this is a project that is, in principle, within our reach. It is likely that it can be realized with the existing technological tools, and with a considerable but not unacceptable financial investment. Several ideas for melting the glaciers have been put forward over the years, the most successful of which is apparently the artificial production of greenhouse gases on the surface of Mars.
Here on Earth, we already know how to produce greenhouse gases such as carbon dioxide, ammonia and freon. The industrial production of these gases is probably one of the reasons for global warming in our country: the gases absorb infrared radiation emitted from the ground, warming the environment. This phenomenon is considered undesirable on Earth, but it is very desirable on Mars. According to various calculations, if we build several factories on Mars that will produce artificial greenhouse gases day and night, we can raise the temperature of the surface of Mars to a level sufficient to allow the melting of the glaciers in only fifty years. There's no doubt that setting up a large factory on another planet is a huge engineering challenge, but it's not unrealistic: a successful combination of proper planning, human astronauts and advanced robots might be enough to get the job done.

On top of that, the global warming process that will be triggered by greenhouse gases is by its nature a process with positive feedback, or in other words - a process that reinforces itself. As more glaciers melt, the red atmosphere will receive more water vapor and carbon dioxide molecules. These two are themselves great greenhouse gases, so will further increase the warming process which in turn will melt the glaciers faster, and so on and so forth. As air pressure rises and temperatures on the surface become more comfortable, it will be easier for astronauts to work outside: they will no longer need heavy spacesuits, but only oxygen masks and warm clothing. Work efficiency will increase and factory productivity will rise.

The next step in the nationalization plan will probably be much slower. As mentioned, the reddish atmosphere is rich in carbon dioxide but poor in oxygen, which is essential for the existence of life on Earth. Those who will be able to supply the oxygen are, apparently, bacteria called 'cyanobacteria'.

The cyanobacteria are able to break down water molecules and release oxygen atoms into the air, while utilizing solar energy in the process of photosynthesis. They are very common on the earth, and are an essential link in the food chain: unlike plants, for example, the cyanobacteria are able to absorb nitrogen straight from the air, and use it to create organic compounds. We find these nitrogen atoms, later, in all other animals in molecules such as DNA, essential proteins, etc.

Mars is very poor in nitrogen, and we will probably have to import large amounts of nitrogen from other places in the solar system - if we succeed in doing this, it is likely that the blues will be able to enrich the atmosphere of Mars with large amounts of oxygen. Experiments conducted on Earth and in space show that there are certain varieties of cyanobacteria that are resistant to extreme cold and other harsh environmental conditions that will prevail on Mars in the first decades of the earthing period. When the amount of oxygen in the atmosphere increases to an adequate extent, we will be able to bring more complex animals to Mars: first algae that will grow in lakes and puddles, then simple and resistant plants and finally shrubs, trees and large animals that will be the last part of the complex puzzle of the land of Mars.

But to her and a thorn in her... the process of oxidizing the atmosphere by the cyanobacteria will, most likely, be a slow process that will last tens or hundreds of thousands of years. Until the environment adapts itself to humans, humans will be the ones forced to adapt themselves to the environment. In fact, even if one day we manage to make Mars compatible with Earth, there are things we will probably never be able to change and will have to learn to live with.

For example, gravity. The gravity of Mars is two-thirds less than that of Earth. How will this fact affect future humans who will be born, live and die on the surface of Mars? One can only guess. The experience of space flights teaches us that the absence of gravity has substantial effects on the body in the long term - from loss of muscle mass, through a decrease in bone density to heart problems. No one knows what effect partial gravity will have: who knows, they might rise taller and dwarf even the tallest basketball players on Earth. Either way, the Martians will most likely not be able to stay on Earth for long periods: their bodies will not withstand the load... Mars will be their true home, for better or for worse.

Even with the dangerous ultraviolet radiation from the sun we will have to learn to live, at least until the amounts of ozone in the atmosphere rise to a sufficient level to provide protection similar to that on Earth. There are two possible strategies for dealing with radiation, and both will have a marked effect on human physiology or psychology.

The first option is living inside closed and protected buildings on the ground, or in underground caves. The writers of science fiction often imagined the closed buildings as spacious domes, but in practice the shape of the dome is not necessary: ​​it is possible to live in flat, low and spacious buildings similar to shopping centers and malls on Earth. Again, from an engineering point of view, this is a challenge that can certainly be met: the Mall Of America in the state of Minnesota in the United States,

For example, it covers over 700 square meters, and is well isolated from its surroundings. It can house thousands of people without difficulty. In fact, although Minnesota is one of the coldest states in the United States, there is no need to turn on heating in the public spaces of the Mall of America: human body heat and the heat emitted by the lighting are sufficient and allowed for this purpose.

The Martians will spend most of their lives inside these large structures, and will rarely go out to the surface and for short periods only, so as not to be exposed to the carcinogenic radiation. How will their psychology be affected by this lifestyle? Will they become a nation of agrophobes, who are afraid of open spaces? Will new social structures develop to adapt to the new reality? We won't know until we try.

The second option for dealing with radiation is to proactively change the human body. We don't know how to do it today, but many scientists are convinced that in a few decades we will have the tools to change our bodies drastically if we so choose. Perhaps we can implant nanometer metal particles in the epidermis layer so that they repel the dangerous radiation, or perhaps perfect the DNA repair mechanisms in the cells to quickly repair the damage caused by the radiation. Such physical changes may seem far-fetched to us, but it is likely that at least some of the Martians will gladly accept them, in exchange for a sunny life on the surface, and in addition, such changes are economically preferable to erecting large and expensive buildings.

The last sentence leads us, naturally, to what is probably the biggest obstacle on the way to land on Mars: money. It's hard to see any country agreeing to put the good of all humanity before the good of its own residents, and finance the project to land on Mars. Moreover, according to international law, no country can claim sovereignty over the Red Sea.

This point is of great concern to the members of the Mars Society, and several of them have come up with a number of creative ideas to finance the project. For example: the sale of large areas of land to speculators who will bet on the increase in the value of the land after the end of the nationalization process. According to various calculations, marketing six and a half percent of the surface of Mars at a cost of only ten dollars per acre may bring in over twenty billion dollars. The nationalization project will be much more expensive, of course, but the initial funding will give an important boost to the initial efforts. Additional funding can be obtained through advertisements, sponsorships and selling seats on the spacecraft to billionaires, as is already being done on the space station.

Supporters of Mars colonization have another proposal, which would greatly reduce the cost of human settlement on Mars. NASA's existing plans to send astronauts to Mars assume that the journey to the Red Planet will be two-way: we will bring the astronauts to Mars, and then return them to Earth, like the astronauts we sent to the Moon. There are those who think that this basic assumption of a two-way journey is wrong: the necessity of sending the astronauts on their way with enough equipment also to return to Earth makes the cost of the entire journey so high that it prevents it from starting in the first place. According to some estimates, a one-way trip will only cost ten percent of the cost of a round trip.

The opponents of the idea claim, as expected, that the chances of survival on Mars are so low that it is actually a suicide mission. This claim does not particularly impress Buzz Aldrin, one of the first two astronauts to reach the moon and an enthusiastic supporter of the idea of ​​Mars to Stay, a one-way journey to Mars. In an interview he gave in 2010, Aldrin compared the travelers to Mars to the first settlers in the Americas after its discoveries:

"If you are going to fly to Mars, you have to make the decision that you are staying there forever. The more people we have there, the more supportive environment we can create. Except for extremely rare cases, the people who fly to Mars are not supposed to return to Israel. If you are on Mars, you stay there.”

There is almost no doubt that among all the billions living on Earth, there will be thousands of volunteers who will be willing to take the risk and buy a 'one-way ticket' to Mars. Experience teaches us that pioneers, in any field, are special people who are not easily deterred from dangers and difficulties. It is also possible that the human society that will be established on Mars will be based on the values ​​of its founders, in the same way that the founding fathers of the United States founded it on the basis of innovative values ​​of freedom, equality and justice that were different from the values ​​accepted in most European countries at the time. In other words, it is possible that colonizing Mars will not only lead to changes at the level of the individual person, but also to a new human society with fundamentally different values ​​from ours.

In conclusion, we started the article trying to understand how humans could change other planets to adapt them to their needs and we discovered that the earthing, if we put it into practice, may change us to no less extent, whether individually or as a society. There is a certain amount of poetic justice in this, if you will.

[Ran Levy is a science and technology writer, and hosts the podcastMaking history!'– Radio program about science, technology and history: ]