Planet Mars has intrigued humans for centuries, as a place of possible life, or a place to transform for living.
The more we explore Mars, the more we are convinced that there is no life there, currently. And I don't think we'll ever find any life there.
But of all the planets in the Solar System, Mars is the friendli-est place to visit. It's day is about the same as that on Earth. It's temperatures drop only to 100 degrees below 0. It has a surface that you could walk on. It even has ice, that could possibly be turned into liquid water..
So, been such adventurous creatures we are, humans have dreamed of visiting Mars for centuries... and maybe even colonizing it. Since there are no places on Earth left to colonize, space is our final frontier. But what would it take to colonize Mars?
First, we'd need to get there. Mars is not that far. With present technology, we could get there in a couple of years. In fact, a couple vehicles sent from us, are already driving around its surface. But sending humans would be a little more difficult. The reason humans have been able to fly to Moon without dying on the way, is because the Moon is close enough to fall into the region protected by Earth's magnetic field. That field deflects much of solar energy. If we go outside of that protected zone, the chances of getting sick with cancer, and who knows what other diseases, are greatly increased. Some say the probability is so great, it is guaranteed that astronauts trying to fly to Mars, will die of cancer.
But, suppose some humans are lucky enough to get to Mars healthy. After all, chances of getting cancer on this planet, are extremely great as well.
Mars looks like a dessert on Earth. So if humans were able to get there alive, they would be able to walk on it and drive on it. They would need to stay in space suits at all times, however. Any hole in the space suit caused by Mars' frequent tornadoes or rocks from the surface, would kill the person immediately. There is no oxygen on Mars. And temperatures drop 100 degrees below 0, every night.
So, even if it was possible to visit Mars, staying there to live, would be a completely different matter. Walking in a space suit all your life would not be very comfortable, and ordering oxygen from Earth on a regular basis, would be very expensive.
So the first thing the people who plan Mars missions would do, is to try to raise air temperature on Mars, to make it warmer. How do you do that? Well, according to today's popular global warming hypothesis, we already know how to raise temperature on a planet. We could do that by putting out a bunch of pollutants into the atmosphere. A space probe would be sent to Mars, that would produce CO2, and send it into the atmosphere. In about a hundred years, that should raise the temperature to tolerable levels. The amount of CO2 that would need to be produced, would be quite high though. With all the pollution we produce on this planet, it's still debatable whether we make any impact on the global temperature.
Now, let's say this space probe was able to produce enough CO2 to raise the global temperature of Mars, what would that do? Well, beneath its surface, Mars is believed to contain frozen reservoirs of water. If we were able to unfreeze Mars, that ice would begin to melt, and create lakes and streams of liquid water throughout the planet. And wherever there's water, civilizations are able to spring up.
Once Mars has liquid water, we can bring plants from Earth, and plant them there. Hopefully, they like the conditions and begin to grow. It's difficult to get plants from one Earth's continent to grow on another continent, let alone another planet.
Then, if plants are able to grow on Mars, they could produce oxygen. And once there's oxygen, humans on Mars could walk around without space suits. Unless new techniques of producing oxygen are invented, the process would take about 10,000 years.
As these experiments are performed, how many colonies of settlers would die from all sorts of new diseases? That would probably not stop us, however. As of December 2013, 200,000 people have already applied to live on Mars. First flight to take 2 lucky humans to Mars, for a one-way trip, is scheduled for 2025.
Sources:
http://www.cnn.com/2013/12/10/tech/innovation/mars-one-plan/