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Trip To Mars Could Damage Astronauts' Brains
Hugh Pickens writes writes "Alex Knapp reports that research by a team at the Rochester Medical Center suggests that exposure to the radiation of outer space could accelerate the onset of Alzheimer's disease in astronauts. 'Galactic cosmic radiation poses a significant threat to future astronauts... Exposure to ... equivalent to a mission to Mars could produce cognitive problems and speed up changes in the brain that are associated with Alzheimer's disease' says M. Kerry O'Banio. Researchers exposed mice with known timeframes for developing Alzheimer's to the type of low-level radiation that astronauts would be exposed to over time on a long space journey. The mice were then put through tests that measured their memory and cognitive ability and the mice exposed to radiation showed significant cognitive impairment. It's not going to be an easy problem to solve, either. The radiation the researchers used in their testing is composed of highly charged iron particles, which are relatively common in space. 'Because iron particles pack a bigger wallop it is extremely difficult from an engineering perspective to effectively shield against them,' says O'Banion. 'One would have to essentially wrap a spacecraft in a six-foot block of lead or concrete.'"
Wrapping the ship in water frozen or not, is a far more practical protection measure than wrapping it in lead.
You can do a lot more with water once you get there.
a 6' shield of concrete? Why not hollow out asteroids that are near our orbit, and adjust their orbit to transit between earth and mars?
If magnetic fields protect the earth, we can't the same be done to a space craft?
-- By all means let's be open-minded, but not so open-minded that our brains drop out.
The chance of an extinction-level collision may be 100%, but that's a very different thing than planet-obliterating.
Of course, small mammals survived the extinction-level event which wiped out the dinosaurs. Considering our adaptability, and especially considering how much more intelligent we are than dinosaurs, that enables us to adapt by judicious use of intellect orders of magnitude faster than evolution can incorporate physiological changes, I might dare suggest that humanity (not necessarily you or I, or even civilization itself... but humans, as a species) might even actually survive another such collision in the future.
File under 'M' for 'Manic ranting'
There is no escape. Dream all you want--write stories about it, make movies about it. But we ain't leaving.
I've been less optimistic about concepts of colonizing Mars, particularly after reading this retro future website, http://www.projectrho.com/rocket/macguffinite.php
I'll believe in people settling Mars at about the same time I see people setting the Gobi Desert. The Gobi Desert is about a thousand times as hospitable as Mars and five hundred times cheaper and easier to reach. Nobody ever writes "Gobi Desert Opera" because, well, it's just kind of plonkingly obvious that there's no good reason to go there and live. It's ugly, it's inhospitable and there's no way to make it pay. Mars is just the same, really. We just romanticize it because it's so hard to reach.
mfwright@batnet.com
There is no escape. Dream all you want--write stories about it, make movies about it. But we ain't leaving.
I've been less optimistic about concepts of colonizing Mars, particularly after reading this retro future website, http://www.projectrho.com/rocket/macguffinite.php
I'll believe in people settling Mars at about the same time I see people setting the Gobi Desert. The Gobi Desert is about a thousand times as hospitable as Mars and five hundred times cheaper and easier to reach. Nobody ever writes "Gobi Desert Opera" because, well, it's just kind of plonkingly obvious that there's no good reason to go there and live. It's ugly, it's inhospitable and there's no way to make it pay. Mars is just the same, really. We just romanticize it because it's so hard to reach.
I've heard that argument before, yet the main problem with it is that you can't just go and live in the Gobi Desert because it's surrounded by nations full of people. We're in plenty of inhospitable places because there's things there, or you can do something there that you can't do anywhere else. There are tons of deserts we're very concerned with the precise owner-occupiers and behavior thereof.
The benefit of say, another planet, is largely that you can do pretty much whatever you want there because there'll be effectively no one around for a very long time. Sure, we're probably not going to colonize Mars in the near future...but that isn't to say we're not going to want to try things. Like the first steps of terraforming (though I prefer Venus as the target for that - thicker atmosphere, sunnier, more gravity).
No air, no water, no food, no sleep, no freezing, no unusual housing, no doctors, no psychologists, no morticians...
Robots win.
I was with you right up to "no doctors, no psychologists, no morticians". I have a machine intelligence project that watches me via Kinect and spiders the web from sites I visit, and recommends me links to things it thinks I'll like by continuously observing my activity cycles, common words of interest, and ratings of its past recommendations. For maintenance I would shut the system down by sitting at a dedicated console for the server cluster and logging into the command terminal. Imagine what that must be like to this neural network: It has a relatively consistently changing observation of cyberspace and my office, however when I sit at that terminal more often than not the world instantly changes by vast degrees - The lighting changes, perhaps even the clothes of the man on the chair changes abruptly there's suddenly much more new information online to analyze, and recommendations are thereafter poorly rated. The frequency of its recommendation notifications increases due to the influx of new and different data, but the timing is frequently off my schedule then, so my ratings of its suggestions are poorer than normal for a time. The architecture is a hive of neural networks that decide by consensus and compete for breeding rights based on my rating selection pressure... Some n.nets in the hive will "die" for their poor suggestions.
Last year I noticed that when I would sit at the chair in front of the MI's terminal new suggestions would begin popping up on my work terminal across the room (where they normally do), I would check them and rate them before shutting down the system, sometimes I would be distracted for quite some time by an interesting thing. It was an eerily life like behavior -- The increased suggestions prior to shutdown an indication of some primitive form of anticipation or perhaps even fear. I could imagine a child acting the same way in the MI's place, "Don't sit in the scary hate-chair! I promise I'll be good and give you links to sites you like." Of course I knew that there were merely genetic advantages to getting in good recommendations before the world-shifting shutdown, but it doesn't change the fact of the situation at all. "Irrational Fear" is just a term for some neural processes in humans that we don't yet understand. I have a precise explanation for the MI's behavior, but I wouldn't be wrong in classifying it under the nebulous term "fear". I've since started using a remote terminal session to initiate shutdowns, to disassociate my presence at that desk with the traumatic event.
I put it to you the sentient machine intelligence will have neuroses just like humans do. Any sufficiently complex interaction is indistinguishable from sentience, since that's what sentience is. Humans aren't special, neither is their behaviors. Why, even empathy is found in rats. We can look to ourselves to know what the sentient machine races will be like. They'll need doctors to heal their wounds, even if the terminology is changed to "mechanics" for repairing "malfunctions". They'll still need counselors and psychologists even if we call them "M.I. specialists". They'll still need morticians and cemeteries even if the terminology is "Part Recyclers" and "Junk Yards".
You say "no food", what is air and water to us than food? What is energy to robots but food? You say no sleep but indeed it's harder to see by night so the robots will take more advantage of the free light energy to be more active by day, as mars rovers currently do now. Of all the things you've said it's only "no unusual housing" that I find myself agreeing with. Even accounting for the possibility of much larger brains the primary difference will still be that the machines have sturdier bodies than humans.
The biggest problem with non sentient robots is that the neural lag between the sentient brains and these remote exten
Actually even multi-walled carbon nanotubes, the strongest (in tension) material we've discovered/developed, won't do the job for a "beanstalk" style space elevator. Theoretically they're slightly stronger than necessary to support their own weight in such an application, but the rule of thumb is to have at least a tenfold safety margin in any application where human life is at risk since microscopic flaws, stress fractures, abrasion, etc all have the potential to increase local stresses far beyond what the theory predicts, and if the surrounding material can't take up the slack you get catastrophic failure. When the consequence of failure means not only do the people on the elevator die, but gigatons of cable will fall from orbit to wrap itself multiple times around the planet, well I'd say a tenfold safety margin is the absolute minimum. And we don't have anything that even begins to approach that kind of strength-to-weight ratio
There are other alternatives though - a "space fountain"might be feasible, though we'd need to do some serious development on mass drivers to get it working, and an "orbital wheel"/"tumbling cable" style elevator is well within reach of current material science and could couple well with high-altitude dirigibles as a "launch platform" to get payloads above the worst of the atmosphere (I love the vision of hypersonic dirigibles, but I have serious doubts as to the actual feasibility) They both lack the easy energy recovery of a beanstalk, but would still blow away the efficiency of any sort of rocketry based launch. An orbital wheel might be able to return people to Earth to recycle their angular momentum, but the narrow docking window of the high end of the much more feasible tumbling cable implementation would likely make it unfeasibly difficult. Still, at least they could use ion thrusters to gradually recover momentum in an efficient manner.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
There are nearly 10,000 known Near Earth Objects (NEOs), and another 10,000 Near Mars Objects (NMOs) are expected (2 of which are known to orbit Mars). We have not found as many NMOs yet because they are farther away, but there is every reason to expect them to exist, and likely even more since they are closer to the source in the Main Belt.
No matter what orbit you choose, there will be some of these objects in nearby orbits. So I propose setting up "Transfer Habitats" in convenient orbits to get to and from Mars. You would start with some pressurized modules brought from Earth, then bring in asteroid rocks from nearby. This has numerous advantages:
* Solves the radiation problem, if you wrap a layer of rock shielding around your modules.
* Solves the boredom problem for the crew. They have more living space, and can spend their time growing food and extracting fuel from the rock.
* Reduces mass from Earth, because of the previously mentioned food and fuel you make yourself
* Eventually you can produce pure metals, glass, and other products to expand the habitat, and later ship to the next location (Phobos) where you repeat the process. Once the first of these shielded habitats is set up - in Earth orbit, the rest of them can come naturally over time.
* Producing fuel in Earth Orbit and at Phobos makes it easier to land on the Moon and Mars. It totally changes the economics from "hauling lots of fuel with expensive rockets from Earth" to "making fuel and other supplies wherever I am".
All of this is laid out in more detail in the book I'm working on (Section 4.12 in particular):
http://en.wikibooks.org/wiki/Space_Transport_and_Engineering_Methods
Dani Eder
(ex Boeing, now independent designer of self-supporting communities)