Even though Mars has resources that can be used for a sustainable settlement if humans are ever going to settle down on Mars, we may need to become a little less human. But let’s explore the possibilities. Let’s say your crew mission to Mars, which NASA wants to start flying in the 2030s, was successful, despite you having been exposed to high radiation loads, bone-wasting microgravity and other hazards that are moving strangely, you are now on Mars.
Firstly, you’re going to need a pressure vessel. Mars’s atmospheric pressure is less than 1% of Earth’s. You can think that there is no pressure at all! Being on the surface of Mars is almost the same as being in deep space. You know how it feels to be in space because you completed so many video games set in space. You better bring a nice container to hold air in. And try to make it as big as you can. Also, you’re going to need oxygen. There is a possibility that you will want to breathe on Mars, so you’ll need to have something in that pressure vessel. Lucky you, it’s possible to get it from Mars itself. The atmosphere is very thin, but it is present and it’s almost entirely carbon dioxide. Or you could just grow some plants. What’s more? You’re also going to need radiation shielding. Earth’s magnetic field protects us from most of the nasty junk sun spits out at us. Mars has no such luxury. All kinds of radiation reaches the surface. Of course, if you want to have cancer so much, skip this part. But if not, you’re going to need a radiation shield. The easiest way to do that is to bury your base in Martian sand and rocks. And what about some water? Again, you can get it from Mars! Martian soil apparently has about 35 liters per cubic meter. All you need to do is scoop it up, heat it, and strain out the water. Once you have a good supply, a simple distillery will allow you to reuse it over and over. Okay, you have oxygen, you have water. Maybe you are into eating? Tell you mama to prepare some meals for you in your lunchbox! Oh, come on! Food is the one thing you need that can’t be found on Mars. You’ll have to grow it yourself. But you’re in luck, because Mars is actually a decent place for a greenhouse. The day and night cycle is almost identical to Earth’s. The total solar energy hitting the surface is enough for your needs. But you can’t just grow plants on the freezing surface. You’ll need a pressure container for them as well. And it has to be pretty big. Just think of how much food you eat in a year and imagine how much space it takes to grow it. Hope you like potatoes. Thinking about that, I guess that you also are going to need energy. However you set things up, it won’t be a self-contained system. You’ll need to deal with heating your home and the greenhouse. The average temperature in Mars is -50C (-58F), so it’ll be a continual energy drain to keep yourself warm. Remember that your oxygenator also needs energy!