The main reason is that Mars is a very unhealthy place, not just for humans but for all life. Forget the temperature extremes. The biggest problem with Mars for maintaining life is that it has almost no protection against radiation. It has no iron core like Earth and thus it does not have the magnetic field that protects humans from cosmic rays and solar mass ejections.
Read this article for more information.
Six feet of soil can shield against cosmic rays as can a few centimeters of water. Since hauling water to Mars hardly seems practical, unless an ample water supply is found on Mars, the "explorers" will have to be satisfied with living and exploring under the surface.
Also, the human body is so adapted to our level of gravity that almost absent gravity (as in the space station) damages bone density. In a large space craft that rotates, you can use centrifugal force to simulate gravity, but how do you do that on the surface of Mars? Not exactly a vacation and no place anyone would want to live for long.
Terraforming isn't practical unless there's a way to give the planet a magnetic field. Otherwise, the atmosphere will simply be lost to space.
What do you think?
Well as long as you've convinced yourself then good for you.
Yes, facts have a way of convincing me:
Rhetoric, not so much.
Look at the populations of two of the fastest growing economies on earth, China and India, and the impact of American teens will be a minor component of the problems.
While that is a point in itself it does not distract from the trend, which is much more important than levels when we are talking long time frames.
What do you believe Levitt and Dubner are talking about below:
"The main mode of transportation produced a slew of the by-products economists call negative externalities, including gridlock, high insurance cost, and far too many traffic fatalities. Crops that would have landed on a family's dinner table were sometimes converted into fuel, driving up food prices and causing shortages. Then there were the air pollutants and toxic emissions, endangering the environment as well as individuals' health."
If you guess cars, you are mistaken. Some problems persist until we suddenly find a solution, as with our previous equine addiction. See lots of horses on the roads these days?
Yeah, in America. China and India - not so much. Exactly my point. I know you can never admit you were wrong though - that's the trouble with magical thinkers.
Did I not mention that I was discussing trends?
Does the fact that more and more people are becoming religious in Russia and China distract from the trend of fewer people being/becoming religious?
"However, who do you think minimalism is a major trend?"
I'm having a hard time parsing that sentence. What were you trying to say?
Can we continue in Norwegian, Danish, or Swedish, or will you allow me some latitude in a language which is not my mother tongue?
"I should really be talking about our current civilization rather than our species."
This sums it up for me. Long term exploration of space will be extremely difficult to get to unless we create a more cohesive and global civilization. The resources it will take are just too great in our near future for one country to go alone in the endeavor of manned space exploration let alone colonization.
RE: "That change is extremely like to be very hard on certain segments of the population because no matter how you slice the cake, someone leaves the party hungry."
Unless, of course, they have the wisdom to diversify.
"it's just a mathematical evaluation of remaining petrol reserves and our energy consumption habits."
You may wish to brush up on your math. While we may run out of economically producible oil or fill the atmosphere with greenhouse gases and kill ourselves, running out of carbohydrates is very far off. A fairly standard field will have a 20% extraction rate, with 35% being world class and 50% currently where the technological advancement stops. Thus most of the currently producing fields will leave 3/4 to 2/3 in situ. Add to that the unconventional sources (shale, heavy, deep water, arctic, etc), and assuming absolutely no technological improvements in extraction or efficiency from today we still will have 100+ years of economically extractable oil at $100/barrel.
As stated though, burning oil "forever" will most likely extinct human kind and is not particularly advisable, even though were not running short in the foreseeable future.
There's always bio-diesel... probably 5 times or more the current price of fuel but I can see the economy adapting to that.
Might not be powerful enough to get a plane into the air though.