Mars is known as the Red Planet and it is about 34 million miles from Earth. There has been much talk about successfully building a colony on Mars in the near future.
It takes 6 months to travel to Mars but only 3 days to the Moon. So why have scientists picked Mars over the Moon?
The following three answers give in-depth information on this subject. The second answer is by the head of the Mars Society.
Mars has an atmosphere that somewhat protects against space debris like micro meteorites, and the moon has no protection at all. The solar system is full of dust and sand sized particles and the Earth and Moon frequently pass through these regions; they are what cause the frequent meteor showers seen throughout the year. However on Earth they burn up harmlessly in the atmosphere, but on the Moon they would be like bullets raining down randomly. Any long term colony on the Moon would need to be under ground for the protection of critical infrastructure and colonists.
There is also a possibility of terraforming Mars through the work of colonies over centuries. The Moon lacks the materials and the gravity for an atmosphere.
Eventually we will likely use the Moon as a launch platform for our space program because of it’s lower gravity well and the presence of water in some of the craters for fuel. That is a very long way off though.
It’s inevitable that we will branch out into space when it becomes economically viable. The first country or company to bring an iron rich asteroid into Earth orbit, and find a profitable way of mining it, is going to make so much money, it will be like a gold rush. Imagine what would happen if SpaceX took possession of a small asteroid with a trillion dollars worth of iron on it. Every enterprise on Earth would be racing to do the same. Once space becomes profitable, jobs, then people, then colonists will follow in it’s wake just like discovering The Americas did 500 years ago.
In the words of Robert Zubrin, head of the Mars society:
As I see it, there are three reasons why Mars should be the goal of our space program: and in short, it’s because Mars is where the science is, it’s where the challenge is, and it’s where the future is.
It’s where the science is because Mars was once a warm and wet planet, it had liquid water on its surface for more than a billion years, which is about 5 times as long as it took life to appear on Earth after there was liquid water on here, so if the theory is correct that life is a natural development from chemistry, where if you have liquid water, various elements and enough time, life should have appeared on Mars even if it subsequently went extinct, and if we can go to Mars and find fossils of past life, we would have proven that the development of life is a general phenomenon in the universe. Or if we go to Mars and find plenty of evidence of past bodies of water but no evidence of fossils or the development of life, then we can say that the development of life from chemistry is not sort of a natural process that occurs with high probability but includes some freak chance and we could be alone in the universe.
Furthermore if we can go to Mars and drill, because there’s liquid water underground on Mars, reach the ground water, there could be life there now. And if we can get hold of that and look at it and examine its biological structure and biochemistry we could find out if life as it exists on Mars is the same as Earth life because all Earth life at the biochemical level is the same—we all use the same amino acids, the same method of replicating and transmitting information, RNA and DNA, all that—is that what life has to be, or could life be very different from that? Are we what life is, or are we just one example drawn from a much vaster tapestry of possibilities? This is real science, this is fundamental questions that thinking men and women wondered about for thousands of years, the role of life in the universe. This is very different from going to the moon and dating craters in order to produce enough data to get a credible paper to publish in the journal of geophysical research and get tenure, okay? This is you know hypothesis driven, critical science. This is the real thing.
Second, the challenge. I think societies are like individuals, we grow when we challenge ourselves, we stagnate when we do not. A humans to Mars program would be tremendously bracing challenge for our society, it would be tremendously productive particularly amount youth. Humans to Mars program would say to every kid in school today, “Learn your science and you could be an explorer of a new world.” We’d get millions of scientists, engineers, and inventors, technological entrepreneurs, doctors, medical researchers out of that, and the intellectual capital from that would enormously benefit us. It would dwarf the cost of the program.
And then finally, it’s the future. Mars is the closest planet that has on it all the resources needed to support life and therefore civilization. If we do what we can do in our time—we establish that little Plymouth rock settlement on Mars—then 500 years from now, there’ll be new branches of human civilization on Mars and I believe throughout nearby interstellar space, but you know, look: I ask any American what happened in 1492? They’ll tell me, “Well Columbus sailed in 1492,” and that is correct, he did. But that is not the only thing that happened in 1492. In 1492, England and France signed a peace treaty. In 1492, the Borgias took over the papacy. In 1492, Lorenzo De’Medici, the richest man in the world, died. Okay? A lot of things happened, if there had been newspapers in 1492, which there weren’t, but if there had, those would have been the headlines, not this Italian weaver’s son taking a bunch of ships and sailing off to nowhere, okay? But Columbus is what we remember, not the Borgias taking over the papacy. Well, 500 years from now, people are not going to remember which faction came out on top in Iraq, or Syria, or whatever, and who was in and who was out and you know….but they will remember what we do to make their civilization possible, okay?
So this is the most important thing we could do in this time, and if you have it in your power to do something great and important and wonderful, then you should.
There is actually a lot of discussion about having a jumping off point on the moon. The main reason is for the science. There has not likely ever been life on the moon, but we know that at one point mars had a lot of liquid water which we know to be incredibly important for life as we know it. Possibly even meaning that the soils there could support plant life for explorers.
Also, the gravity on mars is a lot closer to earth gravity than moon gravity. This means that explorers could stay longer without some of the problems that come with being in less gravity.
Compared to the moon, Mars is more habitable for human settlement. It has a larger atmosphere (albeit not much), a higher gravitational pull, and places where water could be found and extracted.
The moon is pretty close to us, but it has no atmosphere, a weak magnetic field and about 1/6 the gravitational pull of earth. That makes long term settlement pretty challenging as it’s fairly hostile to our way of life. The moon would make a perfect location for a space station similar to the ISS though.
Weak gravity means less thrust is required for lift off and landing. The moon also has some materials on its surface that are great sources of energy (such as helium-3). The lack of atmosphere is perfect for astronomy, and astronauts wouldn’t have to worry about keeping the moon in orbit. It’s not going anywhere anytime soon. The moon’s just plain better than a low orbit space station.
Another reason for Mars is that it’s more of a stepping stone than anything else. If we can get people there then we can get people anywhere in the solar system with a relatively trivial amount of extra engineering. A successful trip to mars could be the spark needed to inspire more space travel for humanity in the future.