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"In this book...I will lay out in detail a plan for a near-term human Mars exploration...

It is my firm belief that we now possess the technology that could allow a human landing on Mars within ten years of any time a decision is made to launch the program. As I write this, it's 2011, and if we launch in October 2022, the first human crew will arrive April 9, 2023. On Mars [this will be] the height of the northern Martian spring. The weather will be at its best, with clear skies and low winds, and a landing will be called for...

The human exploration of Mars is not a task for some future generation. It is a task for ours.

We hold it in our power to begin the world anew.

Let's do it."

The above is found in this fascinating, detailed, and accessible book by Dr. Robert Zubrin with Richard Wagner. Zubrin is an aerospace engineer, president of the aerospace R&D company "Pioneer Astronautics," and the founder and president of the "Mars Society." Wagner is the former editor of "Ad Astra," the journal of the National Space Society.

When this book was first published in 1996, the late, great Dr. Carl Sagan called Zubrin the man who "nearly alone, changed our thinking on this issue." And I can see why! In this spectacular revised and up-to-date book we are shown how a manned flight to Mars can be achieved.

Zubrin's master plan for getting to Mars is called "Mars Direct." It is "the quickest, safest, most practical, and least expensive way" to do so using present-day technology. He explains this plan in detail.

Getting to the "red planet" is only the first step though. There then must be exploration and settlement of Mars. The key to doing these things, as Zubrin explains, is to produce fuel and oxygen on the planet's surface with its own natural resources.

The "ultimate challenge" that Mars presents to humanity is terraforming. Terraforming (meaning "Earth-shaping") of a planet, moon or other body is the hypothetical process of deliberately modifying its atmosphere, temperature, and surface topology to be similar to Earth to make it habitable by terrestrial organisms.

The two biggest factors to consider for terraforming Mars is atmosphere and temperature:

(1) Its atmosphere currently consists of 95% carbon dioxide*, 3% nitrogen, 1.5% argon, and traces of oxygen, water vapour, and methane. Contrast this with Earth's atmosphere which is 78% nitrogen, 21% oxygen, 0.9% argon, and traces of carbon dioxide* and methane. Water vapour is 1% (varies with climate).

(2) Its mean surface temperature in Celsius is -65. Earth's mean is 14.

So, can we transform Mars to make it fully habitable? Zubrin says "we can" and he shows us how it can be done.

A chapter I found most interesting is entitled "Killing the dragons, avoiding the sirens." It deals with the possible hazards of space flight (like radiation hazards and zero gravity). Zubrin explains in convincing detail how these should not limit our dreams of going to and eventually inhabiting Mars.

All of the above is presented in this book's initial chapters. To summarize, these chapters were concerned with sketching out the technical possibilities and the vision of what can be accomplished by launching a human-to-Mars program. For the last chapter, the reader has to "come back to Earth" and consider those obstacles on Earth preventing a human Mars mission. Presented are three different models on how a human Mars mission might be accomplished.

At the end, there's a addendum on the Mars' meteorite discoveries of 1996. The first of two appendices is especially interesting since it outlines seven reasons why we must go to Mars.

Finally, throughout the book are helpful diagrams, informative tables, and black and white photographs. Also, there is a section near the end that has just over 25 black and white glossy photographs of mainly artwork.

In conclusion, this book dramatically shows how a flight by humans to Mars and settling humans on Mars is no longer a...fantasy!!

(revised and updated edition published 2009; map of Mars (colour); preface to revised edition; forward; preface; 10 chapters; epilogue; main narrative 335 pages; addendum; 2 appendices; glossary; notes; references; index; about the authors)

<<Stephen Pletko, London, Ontario, Canada>>

0Commentaire1 sur 1 personnes ont trouvé cela utile. Cette évaluation a-t-elle été utile pour vous?OuiNonSignaler un abus
le 29 juillet 2013
I loved this book and read it in a matter of days, but my wife got bored about half-way through because of the level of technical detail and the author's repetition of his guiding principles. I'm giving 5 stars because I liked those aspects. His technical details paint a crystal clear picture of how the plan would be executed and why it would work. His writing speaks to his belief that this can be done here and now, and that it should be.

If anyone's told you that we can't go to Mars, they're wrong. Here's the bullet points:
* We don't need plasma drives or any other kind of fancy propulsion. Ordinary chemical rockets can get us there and back in six months each way, with 1.5 years stay on the surface in between. That's a great mission!
* The importance placed on radiation in the media is absurd. Cosmic and solar radiation aren't going to fry these guys, they just boost cancer rates to 3% higher than the 40% chance the rest of us already have. Remember the Challenger disaster? Remember Columbia? Astronauts volunteer by the thousands to ride a highly explosive rocket into the vacuum of space. Cancer is not high on their list of worries.
* We don't need to go to the moon again. It has no worthwhile resources. It's just a gravity well that you have to burn fuel to land on and then burn more fuel to get off of.
* We don't need any more space stations. It's orders of magnitude cheaper to build a large rocket on Earth and launch straight to Mars then it is try building anything in Earth orbit.
* We don't need more research on micro-gravity and bone loss. There have been astronauts that lived in space for more than a year and they're doing just fine.

I think the only reason we don't go to Mars is that governments are scared to spend billions of dollars on a mission that will probably kill a bunch of astronauts in the process. The Case for Mars lays out a very safe plan but even if a few astronauts do die it will have been in the service of mankind's greatest achievement. Nobody bats an eye as modern wars cost billions, kill thousands and accomplish nothing that future generations will be proud of.

Let's go to Mars! Zubrin's got a plan and you're going to love reading it!
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le 13 mars 2004
I have had the unique opportunity to meet Robert Zubrin at a couple of conferences. He is a brilliant, funny, visionary, cantankerous engineer who has become a serious leader in the space advocacy community. His personal style comes across in his writing. He's a bright guy with a serious ax to grind about Mars, how we should get there, and how NASA is screwing up.
Most of his criticism is based upon NASA's handling of "the 90-Day Report," the report the agency submitted to President Bush after he called for a manned mission to Mars. What the scientists at NASA came up with was a huge, visionary program that would require every new technology known to manned space activity, from solar power to zero-gravity construction to cold fusion. Oh yeah, a lot of that hasn't been invented yet, will take 30 years to accomplish, and will cost taxpayers $450 billion. It is the bureaucratic mindset that sets Zubrin off.
Mixed in with all the specific technical information are history lessons about exploration and its difficulties, as well as insights on why we need to explore and the value of Mars itself. Since the release of "The Case for Mars," Dr. Zubrin has formed his own space advocacy group called The Mars Society, which is already setting up its own Mars habitat simulator in an arctic desert of Canada.
He has also taken to describing ways in which the government can best fund the mission, such as offering a "Mars Prize" of $30 billion that would only be awarded to a successful mission. Zubrin shamelessly invokes Kennedy, Lindbergh, Frederick Jackson Turner, and others, and jumps in with a "can-do" attitude that will remind the reader of NASA or "Star Trek" in their better days. After reading Zubrin, you find yourself wondering, "Jeez, why AREN'T we going?"
Zubrin also articulates his belief in the value of frontiers. A frontier provides the hope for escape from current problems--government, social hierarchies, ennui. A frontier can generate new materials (like the gold out of California), new ideas of government and freedom, and more potential for innovation and upward mobility. Governments that have to cope with an expanding, dynamic society cannot turn their energies toward controlling limited resources and a stable population. Anyhow, that's one theory. If you'd like the how and WHY for space exploration, this is a good place to start.
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le 8 décembre 2003
I'm a strong proponent of Mars travel, and the U.S. really needed a book like this one. The book is well written and brings the audience in. I could only dream of writing such a coherent book on this subject.
But, here's a big issue that I have with the book. Many people have come to believe that Mr. Zubrin came up with these ideas for ISRU, and other Mars propulsion related topics. In actuality, these great ideas came from a series of conferences called "the case for Mars" ('80's) and published work prior to that ('70's); all of which came about without his input.
All of the engineering and scientific ideas detailed within the book are not his by any means. He's simply an Engineer with charisma that voiced the ideas of others and tried to apply them. I thank Zubrin's predecessors for their ingenuity.
On another note, I must mention my admiration for NASA. NASA ended up receiving harsh criticism from Zubrin, but they later supported his proposals because it was important to their overall goal. It's tough for any organization to do that, but NASA would never let it's mission be stopped by criticism. Go NASA!
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le 14 octobre 2003
I have been interested in the space program for years, and after several years of wondering if Mars would ever be within human reach, I am thoroughly convinced. Contrary to readers who apparently skimmed the book, Zubrin does indicate a variety of launch vehicles, including the Saturn V but also a number of Russian and recent American developments. He also calculates the costs of restarting the Saturn V program and figures them into his equations. He gives weight to monetary concerns that NASA officials seem to have neglected, concerns that deter some politicians and solutions that could make believers of them.
His reasons for going to Mars also make sense. One element, found in five times the abundance on Mars as on Earth, sells on the free market at thousands of US dollars to the kilo. Scientific research is also a benefit, and the discovery of possible Martian life would provide insights into what genetic elements are universal to all life, and which are native to Terra Prima. The medical implications for the global community are staggering.
And contrary to belief, the discovery of life off of the Earth does not discount religion, it is simply a blow to certain, and then only some, Creationists. As a religious person, a born-again Christian, in fact, I would not find the implications of alien life deterring, but exciting, and possibly, should there be intelligent life, an opportunity for evangelism. The religious argument is without merit.
The book is wholly inspiring, and the Mars Direct and Mars Semi-Direct programs needs to be heard in the halls of Congress. An excellent read.
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le 11 septembre 2002
Great Read. Dr. Zubrin is a true scientist and engineer and knows his subject. I read the book with breathless attention all through the night. Kept me up all night. Dr. Zubrin describes how to get there, who should go, how to "live off the land" when on Mars, and why Mars is so special and different than any other planet.
The first half of the book is a must read for any space enthusiast. The Space Shuttle, Space Station are earth orbits, non-exploration projects. We have not gone any further since Apollo 11 . Who gets excited about circulating around the Earth studying MicroGravity.
There are bigger fishes. Dr. Zubrin explains why Mars and only Mars has potential to have harbored life and may in the far future offer a second home for mankind. Dr. Zubrin goes into technical details in book.
However, Dr Zubrin like all smart scientist and engineers, they need to deal with lowly things like politics and economics. Economics is reason we are not going to Mars. The Cold War sent us to the moon because we did not want to sleep under a "Communist Moon" Dr. Zubrin, all space enthusiast out there, need an economics reason. The Cold War is over. Emotional arguments like, exploration, knowledge and curiosity does not cut it anymore.
In the 21st. century we will only go to Mars for one simple reason: Economics. We need a economic way to go there. Estimates range from $500 billion to $30 Billion. Range is too wide. What the hell are we going to do there besides kicking rocks and taking pictures. Are there mineral deposits we can bring back. Dr Zubrin was on the radio recently. All the callers "Joe Six Pack" are asking "what for me". Fortunately or Unfortunately, if we are able to answer this question to the public: we will then have a Missions to Mars. Science is great for Einstein and fellow scientist. The man, woman, child on the street wants to know "whats for me". If Dr. Zubrin can answer this question, we will go to Mars.
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le 8 mars 2002
Kiddies, put your sci fi books away. This is not your parent's Mars.
In this deep and enthralling book, Robert Zubrin lays out, point by point, his method of madness for traversing the intergalactic distances and heading to Mars. Using his Mars Direct plan, we seen a plausible situation in which we could take Mars within the next decade, and begin pushing our boundaries to the so called "final frontier."
Not only does he provide the means on a very achievable time table, he also makes arguments against the so called "dragons" on the way to Mars, namely the threats of solar radiation and other such impacts. Yet, the effect of these are so negligible on the overall mission, Zubrin has us believe that yes, Mars is attainable in our generation.
After we get there, however, Zubrin takes another ambitious step towards the future: terraforming. He sees Mars as an ecological playground. one that we can change and make habitable for the expansion of earth.
All in all, this book is the Mars Bible for the era. It shows us the most sound way to get across the vast distance, stay on the surface, and return safely, while maximizing our scientific payout for the mission. Hopefully, one day we can realize Robert Zubrin's dream and land on Mars within the next decade.
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le 7 février 2002
The first half of "The Case for Mars" convincingly describes an economically viable, technically sound and scientifically relevant plan for a manned mission to Mars. Period.
Unfortunately, there is also the other half of the book... In that part, Zubrin tries to proof why Mars is so much better than other venues (free-floating space settlements, lunar and asteroid colonies, etc) for space exploration and colonization. Nothing wrong with that, but the problem is that Zubrin is intellectually dishonest when building his arguments. They are clearly aimed at "converting" the uninformed general public, even though the price for that is keeping that public misinformed - and thrashing the scientifically sound work of other space researchers in the way. In that sense, Zubrin's arguments are much like those of pseudoscientific groups, like Creationists, for instance.
And, of course, there is the last part of the book, when Zubrin tries to justify Mars colonization in economical terms. Well, that part is so outlandish that I would classify it as science fiction. (And perhaps not even *hard* science fiction.) There *are* books with compelling arguments about economically profitable exploration of the space (e.g., "The High Frontier" and "Mining the Sky"), but certainly "The Case for Mars" is not one of them.
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le 28 août 2000
Hmmm... this is a difficult one to review.
This book is basically an advertisement for the author's "Mars Direct" scheme for manned mars missions.
On the one hand I laud Zubrin for all the time and effort he has placed into thinking up his "Mars Direct" plan for manned mars missions. The idea is certainly appealing and contians much that had never been presented before. Most interesting is his idea to live off of the land to minimize the need for bringing unneeded supplies and fuel.
On the other hand, it is apparent on first inspection that there are no shortage of technical shortcomings for the Mars Direct plan despite it's advantages. Much (if not all) of the hardware that would be required for Zubrin's plan does not exist today or exits in a format that is so far from practical application that for all intents and purposes it cannot yet be applied to this idea. Zubrin seems to assume that everything will work smoothly and that one mission will just flow smoothly into another. Both the US and Soviet space programs have clearly shown that hardware mishaps occur, usually with disastrous results. Zubrin's dependence on unmanned vehicles to go on ahead in advance and land safely as well as on target time after time is very unrealistic. If these unmanned vehicles malfunctioned or crashed everything is on hold for months or years until the problem can be fixed. The text does not even mention possible problems with the Mars Direct approach, a serious editorial oversight.
I don't mean to throw out the baby with the bathwater. Zubrin means well, and if more of us gave this problem the amount of effort he has, we would have been on mars 20 years ago. Read this book for it's novel ideas, but don't buy into them hook, line, and sinker.
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le 26 juillet 2000
Robert Zubrin lays out by far the most believable and technically feasible plan I've yet heard for space exploration in this masterpiece, backing it up with plethora tables, figures, and some (mostly pointless) photos. The book discusses a plan so flawless and effective that nothing can stand in the way of the reader lauding and accepting it. Mr. Zubrin does a good job of trying, though.
The book, in my opinion, is written far too much like a sales pitch, and not enough like a scientific discussion. Instead of curtly dismissing just about every plan, problem, and competitive idea that others put against the Mars Direct plan, I would have preferred a more mature and openly written approach that discussed in more detail alternatives to Mars Direct's exactitudes, the different ways of financing it, and the mission's size. After reading it, I felt like I wasn't given enough information to make a choice for myself that this was not only a GOOD way to go to Mars, but the BEST way.
In summary, reading the book was a bit like reading the American Constitution: vague in some areas, overly restrictive in others; but the underlying beauty of the ideas that were presented was obvious. I give Zubrin six out of five stars for his ingenuity and perseverance, and two out of five for his ability to present them. It all averages out to a very good book.
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