The Case For Mars [?]

[Orca]

I came across this opinion piece the other day.

To Replace The Shuttle: A Mission To Mars

The author is pushing for human exploration of Mars. Fine.

A few of the arguments used by the author are very typical of folks defending human space exploration. 'Human spirit,' global focus on a goal to keep society productive, inspiring the youth to be scientists, technologies and industries that *may* be created, that sort of thing. These are somewhat pithy arguments in my view -ideological beliefs, really - but everyone is entitled to an opinion. My problem with the article is not with its opinion-based arguments.

His other main line of argument: we must find out if life existed on Mars.

What?

It seems to me that if we choose to visit and eventually colonize Mars, the existence of life in the distant past would have little to do with it. Also, the author seems to completely pass over the idea that robotic missions could continue this line of research (at a fraction of the cost and zero risk to human life, I might add).

My biggest complaint with the article is the way he makes careless conclusions from current findings about Mars to further his agenda.

On the discovery of Mars' wet past:

Thus, if the theory is correct that life is a natural phenomenon emerging from chemistry wherever there is liquid water, various minerals and a sufficient period of time, then life must have appeared on Mars.

Which theory is he talking about? Granted, most scientists would concede the possibility that, where liquid water existed for a long enough period, life could potentially have got started. I doubt many scientists would claim anything along the lines of: water existed, ergo life existed.

We have found places where water flowed out of the underground water table and down the slopes of craters within the past 10 years. Indeed, we have detected methane emissions characteristic of subterranean microbial life emerging from vents in the Martian surface. These are either the signatures of Martian life or the proof of subsurface hydrothermal environments fully suitable for life.

We don't know for sure that those flows were actually liquid water. And even if water does still occasionally erupt from underground sources, it quickly freezes and/or evaporates in the Martian atmosphere. Why would the author make that statement? Perhaps so that Mars appears more "friendly" to life? The methane emissions are not yet explained either; assuming that they must be related to life is presumptuous at best.

The author continues by playing down the technological challenges of actually sending humans to Mars. I love the argument, "we have the technology to go to Mars; we can TOTALLY build rockets big enough to do the job!" The problem isn't just getting a spacecraft to Mars (other than cost, which could be argued to be a rather big problem with the whole endeavor). The problem is keeping the humans in the spacecraft alive. We don't have the technology to shield craft from radiation, for example. Effective shielding options that are currently available would be far too heavy to be practical (polyethylene and water to protect against solar wind and cosmic rays, lead for the EM radiation, in successive layers). Eventually a Martian base that was covered in rock and soil might provide protection. However, two or three guys in space suits with a handful of supplies are unlikely candidates for constructing and underground base!

One of the best solutions for the radiation problem is a better propulsion system, such as VASIMR - the less time the trip takes, the less exposure the astronauts must endure. However, such technologies aren't ready yet.

I guess what irks me is that I feel the article is aimed at folks who don't really pay attention to Martian exploration. They read the article and the whole thing appears to be far more plausible than it really is. "I did hear about water or some such on Mars; one of those rover thingies found it!" Then, based on the amazing 'scientific facts' and a lot of touchy-feely sentiment garnered from the article, the reader - with the feeling of an educated opinion - asks, "...why don't we go to Mars?"

[Ann]

I completely agree with you, Orca.

Orca wrote:

On the discovery of Mars' wet past:

Thus, if the theory is correct that life is a natural phenomenon emerging from chemistry wherever there is liquid water, various minerals and a sufficient period of time, then life must have appeared on Mars.

Really? Which theory is he talking about? Granted, most scientists would concede the possibility that, where liquid water existed for a long enough period, life could potentially have got started. I doubt many scientists would claim anything along the lines of: water existed, ergo life existed.

That quote from Robert Zubrin's opinon piece is really quite scandalous. In science, you start with a hypothesis. A hypothesis is an idea or a suggestion, such as the idea that life will get started wherever there is liquid water. To have a hypothesis taken seriously you need something to support it. (If you pose the hypothesis that pink elephants can fly, chances are that scientists will not be interested in helping you test your hypothesis.) In the case of liquid water and life, we have fossil evidence that life has existed on the Earth for a really long time, and a lot of evidence that liquid water has existed on the Earth for a really long time, and very good evidence that all known organisms on the Earth are dependent on water. So there is extremely good evidence that life on Earth needs water, and that life on our planet almost certainly came into existence where there was water. Well and good. But so far we only speak about the Earth. To have your hypothesis about water and life upgraded to a theory about life on other planets than the Earth, you definitely need to find good evidence of life elsewhere, and you need to show that this alien life is dependent on water to exist. Otherwise you have no theory at all, just a headline-grabbing hypothesis. And since Robert Zubrin has no such proof whatsoever, he is frankly nothing but a windbag.

I guess what irks me is that I feel the article is aimed at folks who don't really pay attention to Martian exploration. They read the article and the whole thing appears to be far more plausible than it really is. "I did hear about water or some such on Mars; one of those rover thingies found it!" Then, based on the amazing 'scientific facts' and a lot of touchy-feely sentiment garnered from the article, the reader - with the feeling of an educated opinion - asks, "...why don't we go to Mars?"

Indeed, I completely agree. Robert Zubrin's opinion piece is aimed at people who don't know better, who will feel educated when they have read a disingenuous propaganda piece like Robert Zubrin's, and who will start asking for a manned exploration of Mars without having any idea of what such an undertaking would entail, or how much money it would deflect from other missions whose returns would be much greater at a fraction of the risk and cost.

Ann

[rstevenson]

I am concerned that a few sentences selected from Zubrin's article have been brought over here to scandalize the troops. It's so easy to run off into a corner and argue your case without the originator of the piece in attendance. Maybe one of you should invite him over to join the discussion?

Rob

PS
And those who wish to judge for themselves whether Zubrin knows what he's talking about might want to peruse his page at Wikipedia.

[BMAONE23]

Perhaps one of the functions of the nexr MARS rover (after curiosity) should be sent with the ability to discern and the functionality to look for fossil evidence. I curious to know that if we were to grind down a rock on Earth and see an imbedded mineral of a different sort foreign to the matrix in which it sits, then analize it's mineral content would we call it hematite or would we call it a fossil? Other than physical appearance, is there any other way to determine if a mineral is a fossil?

[neufer]

Other than physical appearance, is there any other way to determine if a mineral is a fossil?

Pink hair and rhinestone spectacles: http://asterisk.apod.com/viewtopic.php? ... 63#p151658
http://www.nathanieljohnston.com/2010/0 ... e-of-life/

[Ann]

Rob, I read Robert Zubrin's page at Wikipedia, and I was impressed. The man has done a lot for science and astronomy.

Still, I find an opinion piece by Lawrence M. Krauss at the New York Times, A One-Way Ticket to Mars, more convincing. Read it here: http://www.nytimes.com/2009/09/01/opinion/01krauss.html

Krauss argues that, given the terrific costs and risks of sending astronauts to Mars, why not admit up front that we are sending them to their graves, and why not cut costs by half by not even trying to bring the astronauts home again?

We might want to restrict the voyage to older astronauts, whose longevity is limited in any case. Here again, I have found a significant fraction of scientists older than 65 who would be willing to live out their remaining years on the red planet or elsewhere. With older scientists, there would be additional health complications, to be sure, but the necessary medical personnel and equipment would still probably be cheaper than designing a return mission.

Ann

[Chris Peterson]

The author is pushing for human exploration of Mars. Fine.

There's not much to argue with the whole human exploration, manifest destiny issue. That's a matter of opinion. I don't happen to agree, but there's no right or wrong in philosophy, just different views.

But there is NO value in a manned mission to Mars for science. That would be a massive waste. We can look at the Apollo missions and see that no science was done. Sure, some instruments were left, but placing them didn't require humans on site. Returning specimens didn't require humans, either. The ISS is another example. It was supposed to be a base for science, and virtually nothing has been done. A few showy little experiments with spiders or crystals, but no important research. Indeed, all the people sent to the ISS spend the vast majority of their time repairing toilets and generally trying to keep the thing from falling apart. A Mars mission will be no different. The astronauts will be so busy just maintaining their equipment and trying to stay alive that there will be little time for research. And no need, since there is nothing they can do on site that can't be done better by a robot. And a LOT cheaper. We could put hundreds of rovers on the surface for the price of a single manned mission. If we're going to find evidence of life, that's how we'll do it- covering a lot of ground, which isn't going to happen with a manned mission.

Of course, given the cost of a manned mission, we'd likely see a huge reduction in unmanned science missions and Earth observation probes, which truly would be a tragedy of the first order.

[rstevenson]

I would never argue in favour of a manned mission to Mars now, if all it consisted of was a few scientists. I would argue strongly that a concerted effort to get off this planet in significant numbers -- into space habitats, to the Moon, and to Mars -- is a very reasonable long-term strategy that our species should be pursuing. Science can be done along the way, of course, but that should not be the main or even one of the main reasons for the movement. Survival of the species is the main reason. All of our space programs so far that involved humans in space have been major steps along that path. Even the robotic missions have been useful steps, since we'll need the help of robots throughout the process. Everything we have done, are doing and will do off this planet gives us information pertinent to that long-range goal.

But my point in speaking up in this thread was not to argue the case for putting humans on Mars, but rather to point out that it was a bit unfair to pick apart a few quotes from an article published elsewhere, without inviting rebuttal from the author of the article being picked apart.

Rob

[rstevenson]

... I find an opinion piece by Lawrence M. Krauss at the New York Times, A One-Way Ticket to Mars, more convincing. Read it here: http://www.nytimes.com/2009/09/01/opinion/01krauss.html

Great quote: "To boldly go where no one has gone before does not require coming home again."

Rob

[neufer]

... I find an opinion piece by Lawrence M. Krauss at the New York Times, A One-Way Ticket to Mars, more convincing.
Read it here: http://www.nytimes.com/2009/09/01/opinion/01krauss.html

Great quote: "To boldly go where no one has gone before does not require coming home again."

Odysseus, Crusoe, Gulliver, etc... ALL came home again.

It is both a literary tradition and a necessary prerequisite for ticker-tape parades, running for office, dancing with the stars, etc.

[rstevenson]

Great quote: "To boldly go where no one has gone before does not require coming home again."

Odysseus, Crusoe, Gulliver, etc... ALL came home again.

It is both a literary tradition and a necessary prerequisite for ticker-tape parades, running for office, dancing with the stars, etc.

ALL good reasons to stay away!

Rob

[Beyond]

What Rob said above.

[Orca]

But my point in speaking up in this thread was not to argue the case for putting humans on Mars, but rather to point out that it was a bit unfair to pick apart a few quotes from an article published elsewhere, without inviting rebuttal from the author of the article being picked apart.
Rob

I linked the entire article. I assumed folks would read it before continuing with the post. I only quoted a few portions to help illustrate specific points.

Rob, you think I am unfairly judging the author based on what he said in the article? Perhaps if I had read his book, I would have found stronger, well-supported arguments. I couldn't say; I hadn't even heard of the guy before I came across the article on one daily perusing of CNN's website.

By writing this article, the author gained access to a wide cross-section of the population, wider no doubt than his base readers. He could have used this opportunity to write an article with an accurate portrayal of current scientific findings and an honest cost-benefit analysis of a program for manned exploration of Mars. But he didn't. Instead he made wild conclusions from data and used non-sequitur arguments to support his beliefs with these conclusions. He filled the rest of the article with indefensible ideological opinion.

Why? I believe he tailored his article to appeal to the masses rather than to make a defensible argument. He was selling his position.

I found this to be rather bothersome; I've thought about it quite a bit. That is the reason I started this thread; I wanted to discuss the issue, not to "scandalize." I feel that science education and critical thinking skills are weak in this country; I am frustrated by those who seem to take advantage of the situation.

[Ann]

What concerns me - and I may be going a bit off topic now - is the glib way some scientists and pseudo-scientists talk about life in space as if it was an all but perfectly proven fact that life is incredibly common out there. Some of these scientists make bold claims that there are hundreds of millions of planets in the Milky Way which are life-friendly, and because they are life-friendly they are also necessarily incubators of life. Many scientists are also happy to announce that among these uncountable alien life planets there must be thousands or millions that are homes to advanced techological civilisations. Listening to the bold claims of some scientists, you almost get the impression that if we build sufficently good spaceships we could visit some of those extraterrestrial-life planets. And then we might find that they are "Star Trek Class M planets" that we could walk about on with no protective gear on, just like Captain Kirk in Star Trek.

Click to view full size image

Class M planet beckoning. Image copyright © 1998 Jeffrey S. Lee.



Captain Kirk walking around with no protective gear on a Class M planet.

How common is life life in the cosmos? We don't know. It could be extremely common, just as common as the most optimistic enthusiasts say. But we don't know. So far we have no proof whatsoever that life exists elsewhere. We don't yet know that we are not the only ones in the cosmos.

Many people will protest extremely loudly and say that the very suggestion that we might be alone is - well, sacriligeous, perhaps. Some people will argue that the very suggestion that the Earth may be special is a symptom of megalomania. Isn't the Copernican principle and the idea of mediocrity in the cosmos the very foundation of modern astronomy?

I'm not saying that we are alone. How could I make such a claim? How could I ever know that we are alone, even if this was the case?

I'm not saying that I believe that we are alone. I believe that life on Earth arose because of natural processes involving elements and molecules that are common in gazillions of places in the known universe. Who am I to say that these same processes haven't been at work on other planets? Who am I to say that they haven't been at work on millions, billions, trillions or quadrillions of other planets?

On the other hand, I do believe this: It is possible that life is so unlikely, and that it requires so many parameters that have to be exactly right, that perhaps it took an entire universe to come up with just one planet where life was possible. And if so, then maybe the Earth was that planet. And maybe the life-forms that it took an entire universe to bring forth are us and the rest of the Earth's biosphere. I don't believe that it is like that, but yes, I do believe that it could be like that.

I take offense when astronomers and popularisers of astronomy (and sometimes pure sensations-seekers) claim that life must be extremely common because, well, hydrogen and oxygen are common elements, ergo water must be common, ergo life must be common. That's no argument, not to me. Not until we have some proof that water brings forth life, either on Earth or elsewhere. As for the Earth, we have no idea how life actually got started here.

This is another thing that bothers me. By saying that life is as common as dirt out there, we trivialize the Earth. By suggesting or implying that we could build ourselves spaceships and go visit other planets and walk around on them without protective gear because they are so Earth-like, we tell ourselves and others that our Earth is the sort of planet that is a dime a dozen. But it is not. To me, it is a real possibility that we, the living things on the Earth, are the only life forms in the cosmos. I don't find it particularly probable, but I can't dismiss the possibility. And I am convinced that there is not a single other planet out there that is so "Earth-life-friendly" that we could settle there without problems. I'm convinced that the Earth's particular biosphere is unique in the cosmos.

Today we are mistreating our planet in a horrible way. But what is our greatest chance of survival? Is it to try to take care of the planet that brought forth the biosphere that our species is a part of and is totally dependent on? Or is it to go to another planet and try to make it Earth-like from scratch? I know I'd settle for the first option, even if - I know - life will eventually become impossible on the Earth because the Sun will become a red giant. Eventually we may have no choice but to leave. But if so, where will we go? Is it going to be at all possible to find a planet that can nurture us the way the Earth has nurtured us?

I'm concerned that too lofty dreams about settling on other planets may make some people think that it doesn't matter if things go to hell on the Earth. We can always go to Mars! And then, maybe, we can settle on Titan? Who needs the Earth?

Ann

[Chris Peterson]

Today we are mistreating our planet in a horrible way. But what is our greatest chance of survival? Is it to try to take care of the planet that brought forth the biosphere that our species is a part of and is totally dependent on? Or is it to go to another planet and try to make it Earth-like from scratch?

And the reality is, given any technology we are likely to have or develop in the next hundred years, the process of getting enough humans off the Earth to produce a genetically viable community would probably do a pretty good number at finishing the Earth off. Rocket launches are very damaging to our atmosphere.