First, you're going to have to live in transparent domes, but eventually, you can transform Mars into an Earth-like planet. You can warm it up.

There is in the lovely Martian landscape not a footprint, not an artifact, not even an old beer can, not a blade of grass, not a kangaroo rat, not even, so far as we can tell, a microbe. Mars and the Moon and Venus... the only planets that we've landed on—are utterly lifeless. ...in our solar system we may discover that there is life only on this world. This says that life is not guaranteed, that life requires something special, something improbable.

Mars is a neighboring planet at about the same level of evolution as Earth, although technologically far more advanced, so they can be of help. They like to help fellow planets who are lagging behind, who are in trouble, who are misusing nuclear energy and causing the planet and themselves to suffer. They have a great heart and wish to help humanity. They do it out of love.

We know that at least some terrestrial microbes can survive on Mars. What is necessary is a program of artificial selection and genetic engineering of dark plants — perhaps lichens — that could survive the much more severe Martian environment. If such plants could be bred, we might imagine them being seeded on the vast expanse of the Martian polar ice caps, taking root, spreading, blackening the ice caps, absorbing sunlight, heating the ice, and releasing the ancient Martian atmosphere from its long captivity.

Mars is a planet which has three levels or zones - zones A, B and C. Zone A is very advanced, has beings who are very advanced indeed. Zone B has beings who are really quite advanced. Zone C has beings whom you would not want to meet on a dark night! Notwithstanding, the kind of evil there is not of the same kind as we get on this planet, because the planet Mars as a whole is within the mainstream of the Will of God, so to speak. Mars is also in the middle round, its fourth round, is not a sacred planet, and so it has evil.

Mars has always captured the human imagination for decades and decades, it’s always been the planet that everyone’s looking toward. Knowing it’s out there, it’s what drives everything that we do.

Unfortunately, all life on earth - the only life we know - represents, for all its current variety, the results of a single experiment, for every earthly species evolved from the common ancestry of a single origin. We desperately need a repetition of the experiment (several would be better, but let's not be greedy!) in order to make a judgement. Mars represents our first real hope for a second experiment - the sine qua non - for any proper answer for the question of questions.

I have to clear away a few popular misconceptions about space as a habitat … It is generally considered that planets are important. Except for Earth, they are not. Mars is waterless, and the others are, for various reasons, basically inhospitable to man. It is generally considered that beyond the sun’s family of planets there is absolute emptiness extending for light-years until you come to another star. In fact, it is likely that the space around the solar system is populated by huge numbers of comets, small worlds a few miles in diameter, rich in water and the other chemicals essential to life.

Besides ensuring the continuance of life, creating a base on Mars would be the most exciting adventure ever!

Is the surface of a planet really the right place for expanding technological civilization?

The Earth is the only world known so far to harbour life. There is nowhere else, at least in the near future, to which our species could migrate. Visit? Yes. Settle? Not yet. Like it or not, for the moment, the Earth is where we make our stand. It has been said that astronomy is a humbling and character-building experience. ... To me, it underscores our responsibility to deal more kindly with one another and to preserve, and cherish, the pale blue dot; the only home we've ever known.

Mars enjoys global warming yet has almost no atmosphere. To my knowledge, there is no industry or human emissions of CO2 on Mars. There is strong evidence that the Sun drives climate on Mars. The Sun is probably also the main driving force for climate on Earth.

There are so many examples of human misuse of the Earth that even phrasing this question chills me. If there is life on Mars, I believe we should do nothing with Mars. Mars then belongs to the Martians, even if the Martians are only microbes. The existence of an independent biology on a nearby planet is a treasure beyond assessing, and the preservation of that life must, I think, supersede any other possible use of Mars.

The Earth is the only world known so far to harbor life. There is nowhere else, at least in the near future, to which our species could migrate. Visit, yes. Settle, not yet. Like it or not, for the moment the Earth is where we make our stand. It has been said that astronomy is a humbling and character-building experience. There is perhaps no better demonstration of the folly of human conceits than this distant image of our tiny world. To me, it underscores our responsibility to deal more kindly with one another, and to preserve and cherish the pale blue dot, the only home we’ve ever known.