Marcelo,

Because there are 7.5 billion people on this world - and changing their habits (and political ideas) is a very hard thing to do.

If one wishes to have another 'backup' of humanity in some fashion, then learning how a small population may survive in another habitat is surely of some use.

As for the money, that goes to pay the salaries of engineers, scientists, and technicians - it all turns into paying for food, rent, mortgages. It's not as if it gets thrown into a furnace.

If you want to consider 'waste', ask yourself why we need weapons of war?

Or diet aids?

The Cassini mission, on which I worked, cost twenty times less (>3 billion USD), then the *annual* American expenditure on diet aids.

Think about that - some nations eat *so much* that they have to spend money to lose weight.

>>> Why spend so many resources and money on Mars and its possible conquest, by a chosen few, and not take care with those same resources and money, our only home? >>>

Because humans are explorers. They are curious. Give them something to explore. What is behind the next hill? We are "running out of unexplored hills" on Earth. What you find there may significantly change the future.

Replace the word Mars in your question with "America". I am sure the same question was asked in Spain in the 15th century.

How different the world would be today if people would have never (re-)discovered America. We would not have this conversation. A lot of modern electronics and computer technology was invented in North America.

Those resources and money WILL change our home (Earth). Which may soon not be our "only" home anymore.

If you want a more tangible, less philosophic reason: I rather have the military-technologic complex of companies build Mars spaceships than military rockets or bombers or aircraft carriers with nuclear warheads.

Most of our problems would go away if we were to just reverse trend and adjust to live with 1 billion total population. In other words, I said most, I should had said ALL our problems are as simple to solve as having less kids and educating them - like China did.

For a $20 trillion dollars World GDP, spending a few billion dollars on the most difficult challenge we can find is appropriate.

Everytime we do that we always come out better. Our computers are the product of space research. Research on new batteries, new solar panels, etc are all being financed by this exploration effort. That is called how to build the Future.

The populace cannot understand that. That said, they would if they were educated properly.

I agree with you James, the investment in Mars is easily justified. Only the development of technology for flying there or the pure knowledge are for me enough. It seems reasonable to explore our surrounding planets and even the Sun. But what is for me impossible to believe is that we are going to be able to live there, at least with our present knoledge. The difference of temperature is too high between day and night or higher between its summer and winter. Also there are not atmosphere or water.

On the other hand, Marcelo, let me to tell you that it is not necessary to compare this investiment with the one of renewed energies or other cares of our envirament natural conditions here in the Earth. It is absolutely necessary to take care of our planet and perhaps we are reaching critical conditions for allowing the present way of life in the planet. For instance, the air doesn't belong to one country or the see but people do all that they want in they countries without being worried of their quality. Earth is becaming a low planet that we treat as a huge world for certain things and small when we think in the last model of airplain!

Daniel,

The absence of a breathable atmosphere does not stop submariners. Nor has it stopped speculative dreams of submerged cities and the like.

There's plenty of water on Mars - exposed as ice at the poles, and below the surface.

If we want a backup of humanity, at a suitably safe distance from any WWIII, then I would prefer an L4/L5 habitat - supplied by a lunar polar 'industrial' centre.

But I'll take Mars over extinction any day.

Dear James,

The search for life in Mars is a good idea, but can be transformed in very bad if you promise it just saying that we are too much people in the Earth to live. That is obviously a very bad and dangerous reasoning, because some crazy people could think that we have more possibilities (at present) than to take care of our planet.

My point is that we can explore Mars, other planets and even exoplanets. That is absolutely normal and belongs to our necessary knowledge, but another thing very different is to justify it by resons as to be necessary due to the future human life on the Earth. I would like to know how the radiation and distribution of energy is on the Sun, nevertheless, I never would wish to live there. One thing is to know our surrounds (without making comparitions with America discovery which was a mistake made not for getting more knowledge but a new commerce line with India).

I don't go to discuss with you about the quantity of water that exists in Mars or the change of temperature and also the importance of making trips to Mars. That is very interesting and technological challenge, at least, what is for me an error is to justify it as place for solving problems of demography.

Daniel,

Indeed, no significant fraction of humanity, for a considerable length of time, will live away from this world. I do not, for one moment, propose the imminent mass-migration of a population: that would be logistically impossible.

Instead, I look to a distant future (centuries?) where outposts, small colonies if you will, exist in a mutual equilibrium: without the expansionist and destructive drives that are within Homo Sapien v1.0. In such a scenario, Earth may well, through the folly of our generation, be unable to support large populations.

That is the goal I have in mind. For if we merely wish to explore, and acquire knowledge (note, I have built hardware that is on Mars) then robots are far better suited to the task.

> because some crazy people could think that we have more possibilities (at

> present) than to take care of our planet.

Our house is on fire.

I am pessimistic about changing the habits of billions. A tiny expenditure (vs. global defence spending, say) on a back-up plan seems rational to me. I donate to ecological charities, I and my wife chose to have no children, we're almost vegans and moved to a city that uses 98% hydro-power. I also promote the development of space - as in the long term, that is an inevitable step once we have grown up as a species.

The future path that we take is always a 'work in progress' and arrived at through the collective averaging of a great many diverse views: and I agree with you that a view that disregards the current problems *entirely* is a dangerous one. Equally, a view that *entirely* avoids more, ah, unusual, solutions (to our biosphere's collapse), is flawed. A middle ground, with a finger in each pie (so as to speak) seems reasonable: and I'll happily volunteer to be the promoter of literally outlandish solutions, as well as those that are in our technical grasp, but not within our political scope.

The obvious solution to colonizing Mars is to bring DNA, or Semem and Eggs and do invitro fertilization there. That is feasible. Bring millions to Mars is nonsensical.

1. So that our home does not stay our only home.

2. Just as with the last big race, it is a national security issue.

Also, "resources" are not fixed. More precisely, though physical resources such as oil and arable land may be fixed, what is done with them or not creates huge differences in what of use becomes available. Personal interest, harnessed, is tremendously effective at multiplying the effective product of these resources. The resulting economy is good for the entire society. The experiment has been run many times. Space programs draw high interest. Large-scale initiatives throw off many benefits. Theoretical "better" use of the raw resources would have to be done by someone, just as effectively. Despite good intentions, that never materializes.

Good point. It is the countries who can afford to spend on research and for competition purposes. There are lots of people who study science and think that studying Mars or other celestial bodies eventually help to solve problems here on Earth.

For example, after visiting the moon, we realize that the moon is moving away from Earth. It follows that our biological clock will be affected in the future.

It's about geopolitics of outer-space. Just imagine for a second that you own Mars since you reached it first (power). Then a very virulent virus -worse than Covid 19-invade our planet and kill millions a day (global threat). Where would people escape? And how much are they ready to pay to escape that imminent death? A LOT OF MONEY... So business is business everywhere even in outer-space. Just saying..