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?
We will not seriously consider colonization of another planet until the astronomers, who track bodies and extrapolate a potential impact w/ earth, give us the bad news about an impending super collision. And then it may very well be too late. Present technologies are woefully lacking and unable to provide the capabilities for colonization. And the biggee, space travel w/ humans onboard takes too long to get anywhere.
I'm waiting for some dimwit to bring up wormholes or "folding space." Like that's going to happen anytime soon (even if it COULD happen, which doesn't even pass the giggle test).
"There are more things on heaven and earth, than are drempt of in your philosophy, Horatio." - that was a line from CSI Miami.
Think "Mobius Strip" --
Whats wrong with taking a long time? If the space craft is a good enough self contained environment and is capable of sustaining a reasonable population indefinately, I see no reason not to populate it with volunteers and send it away.
Also, what about wormholes or "folding space"? Sorry Unseen, couldn't help it after your comment...
From my readings it seems reasonable to consider local space, atleast out to the Kiber belt, as accessible to humans and mostly conventional propulsion systems. Most of the technical issues surround, long term life support, radiation exposure, socialization, issolation, long term low gravity and extreamly unforgiving/hostile space environments. Staying out of high gravity wells, would reduce fuel/propulsion needs, but the human body still needs it for health.
I agree. Of course, it is folly to suggest that, at some point in the distant future (FAR BEYOND 2030, I suspect), that technical advances that we can’t even imagine now might make Mars accessible to humans. After all, even H.G. Wells couldn’t imagine the ball point pen, much less the iPhone. But it’s moot in my case, since I will be long dead.
Ray Bradbury said he thought the rocket was the most important invention in human history because it gave us the possibility of saving ourselves when our planet reaches the end of its life. In essence, Bradbury was saying that the rocket gave us the promise of immortality. Religious folk, of course, already have that comforting delusion. For the rest of us, there is this implicit FAITH that we are not alone, which provides us a kind of salvation; I think that is equally preposterous. I think it’s nothing more than an academic rumination, anyway, because my own gut feeling is that we will become extinct as a species long before we develop the capability to live on another planet, or contact a cosmic cousin species sending us electromagnetic greeting cards.
The most oft-stated rationale for the Mars missions is to determine whether or not life exists beyond our planet. My opinion? It does not. If “Curiosity” actually finds life, no one will be more surprised and chastened than I. The contrived (and biased) Drake Equation aside, there is no solid scientific basis for our anthropocentric yearnings that we are not alone in the cosmos. Realistically, I think life is just another of the countless artifacts of the universe that are unique. To think otherwise is essentially a religious notion. Like belief in God, belief in beings like ourselves, or even the phenomenon of life of any kind existing elsewhere is wishful thinking. We WANT to think we are pre-ordained. I doubt that.
RE: "technical advances that we can’t even imagine now might make Mars accessible to humans"
It's only a 15-minute trip at the speed of light, if you can handle having infinite mass for that long. Actually, if you had infinite mass, it might be simpler to bring Mars to you.
Actually, AT the speed of light you ARE light, right? The question then is how do you slow it down and return it to its original form.
RE: "AT the speed of light you ARE light, right?" - No, light is composed of massless photons, you, on the other hand are composed of - well, I think we all know the answer to that --
Well, you talked about going at the speed of light and nothing but light can go at that speed, hence logically if you are going at the speed of light you are light.
Tachyons can go faster than light, for one.
"People initially thought of tachyons as particles travelling faster than the speed of light...But we now know that a tachyon indicates an instability in a theory that contains it. Regrettably for science fiction fans, tachyons are not real physical particles that appear in nature."—Lisa Randall, Warped Passages, p. 286.