I'm a reasonable fan of Robert Zubrin's because - like millions of others - I share his desire to see humans reach Mars and beyond. The thing is, I'm a little worried that quite a bit of his writing is rather dogmatic. He claims in "The Case For Mars" that if NASA were to be given the go-ahead, an effort on the scale of the Apollo project could initiate a sustained human presence on Mars within 12 years and for under $30 billion, using mostly off-the-shelf components. He calls initially for the landing of an unpiloted Earth Return Vehicle (which will mine its fuel from the atmosphere to combine with the hydrogen it took with it), followed by piloted launches every two years after that. I may have got those figures slightly out because I don't have a copy to hand, but the idea's the same.

Since I don't have the expertise to be able to analyse his claims properly, I am asking all the rocket scientists on Sciforums

How realistic is Robert Zubrin's Mars Express?

No replies?

I can't believe that nobody has an opinion on Mars Express!

Come on... talk to me!

I'm no rocket scientist, but I am a keen follower of Zubrin. One important point to bear in mind is that his ideas are not his alone. You will know, but others may not, that the ideas evolved out of work at Martin Marietta, where he worked, and from the Mars Study Group, centred on the University of Colorado. The point is that we are not dealing with a lone eccentric, but a well qualified and experienced engineer, who has captured the notions of a wide range of similar indiviuals and groups.

On the face of it the most radical part of the proposal, and therefore the one presenting the greatest risk, is the preparation of the fuel for the return journey on Mars. On closer examination, as Zubrin points out, this is actually the surest. The chemical methodology is approaching two centuries in age. Equipment has been Alpha tested already. The manned flight would not leave until the fuel had been generated. Virtually foolproof.

I also like the notion that the crew stay there for some serious exploration. I may just manage to live long enought to see this and I don't want a bunch of astronauts dropping in for a week, with a quick, "That was one small step for a woman" speech. I want to see some serious work done. Zubrin's plans permit that.

That said, I think there are weaknesses in his approach:
1. He is overoptimistic about how quickly we could develop a suitable heavy lift vehicle and certainly underestimates the cost.
2. He is dismissive of the risks of radiation, and has, I believe been challenged on this.
3. The micro-gravity of the voyage is a problem. He wants to spin the craft at
the end of a tether attached to a spent rocket housing. I think NASA still remembers almost wiping out two Gemini astronauts with a similar stunt.
4. Someone tell me any manned venture by NASA that came in on budget.
5. NASA will get all jittery about safety instead of educating the public with a few facts - like how many people died devloping aeroplane flight. If we had employed the same safety standards then as now we'd still be flying around in biplanes, wearing goggles. I'm not saying be cavalier about safety, but to paraphrase Sagan, "Extraordinary results, require extraordinary risks."

In summary, I beleive it is a viable proposition, with amendments and a slightly higher cost. Lets say 100 billion absolute tops. You get a planet, a re-invigorated industry. And best of all the Americans can stop invading other peoples countries in order to feel good. [Note to all Americans: the last statement is somewhat tongue in cheek. If you want to argue about it pm me, or start another thread. This one is about Mars and getting there. OK]

What would be the point of going to mars? Since setting up any kind of cost-effective industry would be impossible with our current technology, the only benefit that I can see would be the scientific knowledge that we would gain about Mars. I suspect that we could uncover far more scientific knowledge here on earth for the same amount of money.

We should go for the science: we cannot tell how it might revolutionise a multitude of sciences until we go there. Dollar for dollar we might gain more with earth based science, but the potential for major discoveries is greater on Mars. (When you play roulette are you going to bet on a single number or play it safe and stay on red and black?)

We should go for the technology: precisely because we could not establish a viable manufacturing industry with current technology, setting up on Mars would force a rapid development of technologies, a proportion of which would have applicability here.

We should go for survival: you may feel that we are screwing one planet up already and we should leave it like that. That is not an opnion I would share. After three and a half billion years of directionless evolution we are the first creatures who can choose their destiny, but that destiny is fragile. A comet strike could end it all for us tomorrow. We need to spread. (And if that's my DNA speaking, fine.)

We should go for the adventure: its what we do. We came down from the trees to walk the savannas upright. We walked out of Africa. We prodded and we pricked nature till we had enough understanding to hurl three hairless primates across quarter of a million miles of vacuum in a flimsy capsule and stick a flag in the lunar dust. What glorious arrogance.

We are ready for the next step.
We are ready to leave the womb.
We are ready to choose our destiny.

We should go for the science: we cannot tell how it might revolutionise a multitude of sciences until we go there. Dollar for dollar we might gain more with earth based science, but the potential for major discoveries is greater on Mars.It's doubtful that we'll learn anything much beyond Martian geology. If you want to maximize the amount of scientific advancement for your dollar, I can pretty much guarantee you that you'll learn more by investing your billions in research laboratories here on earth.(When you play roulette are you going to bet on a single number or play it safe and stay on red and black?)You're the one proposing a huge bet on a 'single number' that has a low probability of return relative to the other 'numbers'.We should go for the technology: precisely because we could not establish a viable manufacturing industry with current technology, setting up on Mars would force a rapid development of technologies, a proportion of which would have applicability here.I'm all for investing in the development of revolutionary new launch technology and space vehicles, but Zubrin's plan doesn't call for that. He wants to use "off the shelf" technology that already exists.We should go for survival: you may feel that we are screwing one planet up already and we should leave it like that. That is not an opnion I would share.No matter how badly the ecology of Earth is damaged - even if there's a major comet strike - it will probably never be easier for us to survive on Mars. Even a bad comet strike probably won't turn the earth into a -70 C wasteland with no oxygen and too little gravity to sustain a breathable atmosphere.

It's doubtful that we'll learn anything much beyond Martian geology.
I could say that is enough for me as I was a geologist, but the key word in your phrase is doubtful. Which introduces:
You're the one proposing a huge bet on a 'single number' that has a low probability of return relative to the other 'numbers'.
Exactly. If you want to win big you have to take big risks.

.I'm all for investing in the development of revolutionary new launch technology and space vehicles, but Zubrin's plan doesn't call for that. He wants to use "off the shelf" technology that already exists.
Im not talking about launch vehicles. (Though he has proposed bringing back the Saturn V, which in my view was the finest rocket ever constructed.) I am talking about the technology that would be developed on Mars to extract and process and produce minerals, chemical feedstocks, plastics, building materials, metals, etc. In short to develop an entire industrial base and associated infra-structure.

No matter how badly the ecology of Earth is damaged - even if there's a major comet strike - it will probably never be easier for us to survive on Mars.
Do you want to take that chance? I don't. When I put my 10$ on '24' I had a couple of dollars sitting on black.

I notice you offer no counter to the 'destiny' argument. Not your cup of tea?


Shenzou, don't you mean to call the project Mars Direct? Surely Mars Express is the ESA probe currently in orbit and that carried the ill-fated Beagle2? Or has Zubrin repackaged?

I could say that is enough for me as I was a geologist, but the key word in your phrase is doubtful.Sorry, but it’s just silly to try to use scientific advancement as a reason for going to Mars when you could get much larger scientific returns for your dollar here on earth. Short of finding the wreckage of an alien space ship on mars that’s filled with all sorts of fabulous new technology, I don’t believe that a Mars mission is an economically sane way to increase our scientific knowledge. Exactly. If you want to win big you have to take big risks. There’s a difference between taking a big risk in exchange for a large potential payoff and taking a big risk in exchange for a tiny potential payoff. Doing the former makes you a gambler – doing the latter makes you an idiot. The potential payoff for a Mars mission currently seems very small, both scientifically and economically. There is nothing terribly important that we can learn in terms of scientific knowledge by sending people to Mars, and there isn’t any imaginable resource on Mars that would be worth the cost of shipping back to earth with our current technology.

Great debate, both of you. Thanks for responding.

Sorry. I did of course mean Mars DIRECT, not Mars Express. Whoops.

Ophiolite, I wasn't aware that they tried that tether trick during Gemini. What was the result? Assuming the radiation isn't a complete show stopper, what do you think would be a realistic timescale for the development of a new heavy lifter? Saturn 5 was developed in less than a decade wasn't it?

I am very pro-humans-to-Mars, although I can see both sides of the argument. It makes you feel a little bad to support the cause so vehemently when you think of the wonders that $100 billion could do for so many people down here. When I manage to forget that though (so callous, I know) I can't help but see the endeavour as (cliche warning!) an inevitable first step towards a glorious destiny. I don't doubt that the challenges faced by Mars' first colonists will reinvigorate terrestrial industry. It may even help pave the way towards exploiting the riches of the asteroids. In short, I agree with everything Ophiolite posted.

But here's another question: If a robotic explorer detected simple life on Mars, do you think that the case for sending humans to Mars would be strengthened or weakened?

I find out in the next few months whether I will be appointed to the United States Airforce Academy. Studying: Astrophysics/Astronautics and training to be a pilot afterwards. You can figure out where im going with this ;) See you on Mars.

Its going to take a bit more than 30billion though. Cassini-Huygens was 3.5 billion alone...

Later
T

Fantastic! Good luck.

Of course the first people on Mars will be astronauts by definition, but will there be much call for astrophysicists?

I am very pro-humans-to-Mars, although I can see both sides of the argument. It makes you feel a little bad to support the cause so vehemently when you think of the wonders that $100 billion could do for so many people down here. When I manage to forget that though (so callous, I know) I can't help but see the endeavour as (cliche warning!) an inevitable first step towards a glorious destiny. I don't doubt that the challenges faced by Mars' first colonists will reinvigorate terrestrial industry. It may even help pave the way towards exploiting the riches of the asteroids. In short, I agree with everything Ophiolite posted.
There is no doubt in my mind that we would develop new technologies if we sent people to Mars – the question, however, is whether we could develop even more new technologies by spending the money directly on R&D here on earth.

For the same $100 billion cost of going to Mars we could:

-give 10,000 new science and engineering students a $50,000 college scholarship every year for the next 50 years
and
- give an extra $100 million to the top ten research institutions in the U.S. every year for the next 50 years
and
- we would still have enough left over to double the NSF budget every year for the next 50 years

Now do you really think that using off-the-shelf technology to send people to Mars would produce more scientific and technological advancement than all that?

Let me be clear: I’m sure that we will develop industry etc. on Mars at some point. I just don’t think that we have reached the point yet where our technology makes it viable. Once we develop cheap launch technology (say, around a few hundred dollars a pound) then going to Mars to establish reseach stations, industry, and even colonies will certainly make sense. I think we should invest in reaserching better, cheaper launch technology before we go – otherwise we’re just wasting resources.

Think of it like this: Your task it to build a factory that will produce very valuble goods on top of a mountain, but there’s no road going to the top. There are basically two approaches that you could take. One option would be to strap some building materials and construction tools to your worker’s backs and send them climbing up the mountain to star construction. The benefit of this approach is that you can start construction immediately. The down side is that it will take a long time to actually build a useful factory, and once the factory is finished there won’t be any good way to get its products down.

The other option would be to build a road up the mountain, which would allow you to haul your building materials, tools, workers, etc up in trucks. Conveniently, it would also provide an easy way to get the factory’s products down once your finish construction. But unfortunately you will have to wait until the road is finished before you can actually start work on the factory, and that might annoy people who are over-eager for work on the factory itself to begin.

Once we have cheap, reliable launch technology it will be easy travel into space to explore, exploit, and discover – but until we have our ‘road into space,’ trying to send people to Mars would accomplish little other than making ourselves feel good.

It's quite a thing when you put it like that!

Obviously you can't reasonably make predictions about future technologies which, necessarily, are unknown at the moment. Nevertheless, I do believe (hope?) that in the long run the technological benefits of a permanent human presence on Mars could outweigh those that would result from throwing money at institutions on Earth. After all, the same argument could be used perpetually, every time we find ourselves in such a position.

Nasor: Just read your last post and I think you make a very good point with a good analogy. It's a logical and economically sound way of looking at the situation, forcing me to disagree merely on the basis that I WANT people to go to Mars now. In glamorous, rickety vehicles directly descended from V2s. I'm impatient and a romantic. What can I say?

There is no doubt in my mind that we would develop new technologies if we sent people to Mars – the question, however, is whether we could develop even more new technologies by spending the money directly on R&D here on earth
No. Which is why I have argued the case based upon science and technology and survival and adventure.

Zubrin also makes a philosophical appeal to the need in the American psyche for a frontier, arguing that Mars provides the best opportunity to create one and revitalise the American nation. As a non-American this has less resonance for me, but it is an appealing argument. If you are interested, read it in the epilogue of Zubrin's The Case for Mars ISBN 0-684-82757-3.

We are consuming earthbound resources at such a rate that if we do not move into space in a vigorous way soon we probably never will. I would like our species to survive. I see serious manned exploration and then colonisation of Mars is one of the best ways of doing this.

There's a terrific book that outlines the economic motivations for space travel (not Mars specifically). It's called 'Mining The Sky' and it's by John S. Lewis. It makes you wonder why we're not out there right now.

After all, the same argument could be used perpetually, every time we find ourselves in such a position.My argument will not apply forever - as our technology increases, the cost of launching things into space (and by extension sending humans to Mars) will go down, and at some point it will make sense to go.

No. Which is why I have argued the case based upon science and technology and survival and adventure.What can I say, I believe your technology argument is unsound.

As for survival, getting to Mars now (rather than 50 or 100 years from now, when we have the technology to do it economically) will have a negligible impact on the survival probability of the human species. Frankly, your survival argument seems ridiculous to me. Even if we established a colony on Mars five or ten years from now, it probably wouldn’t be able to support itself without earth for decades at least – meaning it won’t do humanity any good to be there if the earth is wiped out.

Also, as I have already pointed out, there isn’t any conceivable disaster that could render earth so inhospitable that Mars would be preferable. Short of the moon falling out of orbit and crashing into the earth, the earth will always be a more hospitable place to live. No matter how bad things get on earth we will at least always have enough gravity to support a livable atmosphere. Even a severe ‘nuclear winter’ wouldn’t cool the planet down to the low temperatures of the Martian surface – basically so cold that you would die and freeze solid almost immediately if you went outside unprotected.

That seems to leave you with only ‘adventure’ – which is great, but not necessarily worth $100 billion to many people.

I think the survival argument is perfectly valid if you consider of Mars as a first step towards the wider universe. The human species doesn't have to limit itself to two bodies.

Nasor,
I do understand your points. I will make two final observations, await your responses, and then perhaps we shall just have to agree to differ.
1. A plausible scenario for the next century involves a continuing growth in population, global warming, failure to address the end of oil, and a consequent collapse of the current economic framework. (We have got so accustomed to what we call progress, we cannot envisage a reverse.) If this scenario were to come to pass it is doubtful we ever muster the resources or the desire to make that permanent move into space again. We have a window of opportunity that exists for perhaps only the next thirty years. I concede that this is not an absolute, but the consequences are so severe - permanently confined to the planet - that I do not consider the risk worth taking.
2. You noted in an earlier post that to take a high risk strategy for a potentially large gain made one a gambler, to do so for a small gain made one an idiot. My argument here is that we have always been surprised by the discoveries we have made with our unmanned probes. We literally cannot imagine what discoveries await us on Mars.
3. The 100 billion will produce techological benefits, even using 'off-the-shelf technology'. Not on the same scale, agreed. But we might be able to talk a government into 100 billion for Mars more easily than 100 billion for many smaller less glamorous projects. Finally, add up the money spent on cosmetics and dog food in the US over ten years. Which is more valuable? Mars or lipstick. They are both red after all.

Apologies - the above may read more disconnected than I normally aim for, but family is shouting my dinner is on the table - and it may shortly be in the cat.