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Mars Space Science

Forget Space Travel, It's Just a Dream 542

An anonymous reader writes "The clash of two titans — physics and chemistry — are major barriers to human space travel to Mars and beyond, and may well make it impossible ... at least with current technologies."
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Forget Space Travel, It's Just a Dream

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  • How about (Score:5, Interesting)

    by rossdee ( 243626 ) on Monday April 11, 2011 @09:01AM (#35780278)

    a space elevator aka beanstalk aka orbital tower.

    Once you get out of earths atmosphere and gravity well, you're halfway to anywhere (in the solar system)

  • by Scholasticus ( 567646 ) on Monday April 11, 2011 @09:07AM (#35780334) Journal
    Remember, any kind of space travel was thought impossible at one time ... until the multi-stage rocket was invented. We need more creative thinking and less of this overly pessimistic nay-saying.
  • by tropgeek ( 1945298 ) on Monday April 11, 2011 @09:20AM (#35780466)
    NOM NOM, Nothing wakes you up in the morning, like crushing the hope of science dreamers everywhere.
    To quote Einstein: "Whoever undertakes to set himself up as judge in the field of truth and knowledge is shipwrecked by the laughter of the Gods."
  • by wisebabo ( 638845 ) on Monday April 11, 2011 @09:25AM (#35780518) Journal

    The quick answer (which I'm sure many posters have already said) is don't involve chemistry; use nuclear engines, or ion engines or solar sails or magnetic balloons. There is a lot more energy (million fold) in nuclear bonds that you can get from fission reactors or by using the fusion furnace at the center of our solar system.

    That said, I haven't really heard of good answers to long time LIVING (not just survival) outside of the earth's magnetic field/shield and without one-gee acceleration keeping our bodies reasonably fit. Want to COLONIZE Mars and not just go there for a flags and footprints mission? Well we have no idea if the 1/3 G gravity will keep the astronaut's bones from becoming brittle. Who knows if women can give birth to healthy infants in such an environment or even if we can grow crops there! (I really thought they shouldn't have cancelled the centrifuge that was to be a part of the ISS. Hopefully, if the Falcon 9 works out, it'll be cheap enough to add it later).

    I'm actually a little more optimistic about the long term ability of humanity to spread throughout the cosmos. In just a few decades, hopefully we'll know enough about our biology to really tinker with it. Getting rid of susceptibility to low gravity is a given of course but how about a little radiation hardening? (Some organisms can tolerate millions of times as much radiation as we can). Perhaps later we could learn to deal with decompression sicknesses (like marine mammals) so spacesuit design could become a lot simpler. Maybe we could learn the tricks of hibernation from bears and squirrels so long space flights wouldn't consume so many resources (and be so boring!).

    We might end up not quite the same as homo sapiens. Call it man plus. (For INTERSTELLAR travel, we'll need some pretty spectacular physics or some pretty radical reengineering of ourselves. How 'bout brains in boxes? Or better yet, just software running on commodity hardware?).

    But it might take awhile.

  • Re:How about (Score:4, Interesting)

    by CastrTroy ( 595695 ) on Monday April 11, 2011 @09:27AM (#35780532) Homepage
    Could you put a big magnet on the ship to channel the cosmic beams from the sun and use them to fuel the ship some how? I'm not joking. I'm not that knowledgeable in this area of expertise. But it seems like we have two problems, too much cosmic radiation, and a need for more fuel while in space. Could we harness the cosmic radiation and use it as fuel?
  • Troll! (Score:2, Interesting)

    by Jammer6502 ( 1430197 ) on Monday April 11, 2011 @09:32AM (#35780586)
    Please let us moderate the summaries. Bad summary of a bad article.
  • by Anonymous Coward on Monday April 11, 2011 @09:35AM (#35780616)

    Doc Brown begs to differ:

  • Re:How about (Score:4, Interesting)

    by fuzzyfuzzyfungus ( 1223518 ) on Monday April 11, 2011 @09:39AM (#35780648) Journal
    The 'space elevator' is in a funny position. On the one hand, it is much further away, technologically, than just about any other space related project within our solar system. On the other hand, the development of high performance structural materials is something with immediate commercial applications in all sorts of fields, so there is plenty of incentive to make incremental advances in that direction, whether or not that project will ever be feasible. Most other projects are easier; but have fewer short-term payoffs distributed along the path to completion.
  • by bradley13 ( 1118935 ) on Monday April 11, 2011 @09:48AM (#35780766) Homepage

    Reading Cosmos for science is like reading the National Enquirer for news. TFA presents a false dichotomy: it takes lots of energy to move stuff between space and the surface of the earth. Therefore space travel is impractical. Whats wrong with this?

    • First, one you establish a real, mostly self-sufficient presence in space, there is no moving stuff back-and-forth to earth. Raw materials are abundant, and getting in and out of weaker gravity wells (like the moon) is no problem.
    • Second, getting back into the earth's gravity well takes essentially no energy at all - only control.
    • Lastly, who says that "chemistry" is the only energy source. Nuclear power offers immensely higher energy densities. Like nuclear power for electricity, nuclear propulsion may well be safer than the chemical alternatives [].

    Space travel takes a huge initial investment to establish a real infrastructure, including mining and manufacturing. After that, it's all gravy.

  • by ElectricTurtle ( 1171201 ) on Monday April 11, 2011 @09:59AM (#35780932)
    There is an actual quote from the 19th century that fits as well or better:

    "What, sir, would you make a ship sail against the wind and currents by lighting a bonfire under her deck? I pray you, excuse me, I have not the time to listen to such nonsense."

    Napoleon Bonaparte, when told of Robert Fulton's steamboat.
  • by DarkOx ( 621550 ) on Monday April 11, 2011 @10:10AM (#35781068) Journal

    There are plenty of ideas out there that probably can work. Most of the technology exists, and just needs to be assembled into a single project. Its not even beyond the realm of economic possibility to implement some of these plans they question is why?

    What is there on the moon or Mars to make it worth going there. Why should anyone want to live there? Don't say over population even if the population on earth continues to grow at the current rate somehow it will be along time before conditions here would be more cramped then they would be on space/moon/Mars base. Don't say resources its pretty evident that supporting one person on a space/moon/Mars base would take more resources from Earth that keeping that same person right here on Earth. The only reason to do it is for practice colonizing and for the investment required it probably makes more since to try and simulate things here on Terra.

    There are for the most part know ways to build and power a multi-generational ship There is lots uninterrupted solar power and other radiation out there to scavenge for your day to day needs, and you could bring enough nuclear fuel from Earth to propel the craft. The trouble is where do want to go. Oh and your going to live the rest of your life in this box, you will never see the destination, nor will your children, their children, their children's children, and likely ten more generations after that. That is if you pick someplace nearby and NOTHING goes wrong. Who wants to take that risk and for what?

  • Re:How about (Score:4, Interesting)

    by michael_cain ( 66650 ) on Monday April 11, 2011 @10:10AM (#35781070) Journal
    You properly make the point that all the flashy things that people want to do in space (industry, manned missions to other planets, etc) fail over the same dull, dreary, problem: lifting significant mass to LEO remains prohibitively expensive. Make LEO cheap, and the other things are, if not simple, at least relatively straightforward.

    I always think it is worth pointing out that the US made an important decision between the time Apollo was announced and when it placed men on the moon: millions of poor and elderly would receive health care paid for by the government. TTBOMK, manned space programs have all started in countries that did not guarantee full-blown modern health care for their poor and elderly. Originally, the US and the Soviet Union. Today, China and India.
  • by memyselfandeye ( 1849868 ) on Monday April 11, 2011 @10:16AM (#35781146)

    This summary is such FUD, and the article is nearly so. The author is a Medical Doctor, and if Doctor's had their say humans would have never gone to low orbit in the first place! Physics tells us Moore's Law is not a Law, but rather an idiom that expresses human ingenuity in the field of electronics. Moore's Law does not say transistors can get indefinitely small, it says people can build cheaper and cheaper transistors on larger and larger circuits. I can double the payload capacity of LEO vehicles tomorrow. Give me a 747 at 40,000ft and a rocket, and I'll put up twice the cargo for half the cost of a conventional rocket launched from sea level. Physics says I can do that. I'm not sure what point the author is trying to make with Moore's law, but the comparison between human ingenuity in spaceflight and electronics, and the laws of nature, is mute. Just because it hasn't happened, doesn't mean it is impossible.

    Mistaking a large Keynesian space program that explicitly prohibits large leaps in engineering is a common mistake people make when it comes to the impossibilities of space travel. The space station was built, in part, because NASA and Congress didn't know what to do with the large 'space truck.' What do you do when you've got giant reusable vehicles with a HUGE cargo hold? Apparently, you build a space station with it!

    We have been living continuously in low orbit for decades without a single fatality. The only Americans who have ever died in space died coming and going, but once you’re up there it has been statistically much safer. One would think moving a group of humans 60-100M km over 9-15 months would be quite possible. We've been living in hostile environments here on Earth for almost a century now with submarines, where a person can't exactly go out for a walk 600ft under water. And in the last 40 years or so, the crews of big submarines have continuously lived underwater for months on end. We know how live in enclosed environments for long periods. If 200 men can go months on end without killing each other, I think a dozen over the hill astronauts might be able to do the same.

    The hard part of going to Mars is leaving Earth and then landing safely, landing being the most difficult but NOT impossible feat. Physics tells us that all the elements needed to create breathable air, fuel, water and return fuel for indefinite exploration of Mars can be found on Mars. Physics tells us the power needed to make these compounds can be made on Mars as well. All with ‘current’ technology despite the "low grade" resources, as claimed by the author!

    Physics tells us all the hazards of interplanetary travel can be reduced or mitigated. Physics tells us radiation can be reduced with shielding, as can micro meteorite impact dangers.

    If you want to really learn what Physics says we Can and Can't do, I'd suggest checking out on of the all time greatest book on the subject, "Spacetime Physics" [] by Taylor and Wheeler from you public library.

    You think that's science fiction? How about this. Physics tells us it's possible to put all the DNA of earth on a tiny little probe the size of a dime, complete with tiny robots, that can be quickly accelerated to large fractions of c and travel between stars in decades. These probes can smash into planets and build life for us. Why send our descendants in large cumbersome bodies when you can send the information needed to create them. The technology to do this doesn't exist yet, but we are developing it Now. And physics doesn't say anything here is impossible.

  • by brainzach ( 2032950 ) on Monday April 11, 2011 @10:42AM (#35781430)

    This article is dead on. There hasn't been major progress in making rockets more efficient since the 1960's because the basics of chemistry and physics.

    If we spend hundreds of billions of dollars, we might be able to send a select few men to Mars, but it would be like the lunar landings in the past. It will be a one time event then people will realize that it is a waste of money and resources to do it again.

    The current technology won't work to make space travel apart of our daily lives. It won't support advances like suborbital commercial airplanes, space tourism, colonization, or mining the Moon and comets.

    There has to be major advances in technology to make space travel that are order of magnitudes more efficient before any of these dreams becomes a reality. These technologies are mostly theoretical and probably won't be available during our lifetimes. Until then, we will just continue to spend billions to send a select few into space like we have been doing since the 60's.

Logic is the chastity belt of the mind!