Slashdot Mirror
Mars Explorers Face Huge Radiation Problem
astroengine writes "A radiation sensor inside NASA's Curiosity Mars rover shows that even under the best-case scenario and behind shielding currently being designed for NASA's new deep-space capsule, future travelers will face a huge amount of radiation. The results, based on Curiosity's 253-day, 348-million-mile cruise to Mars, indicate an astronaut most likely would exceed the current U.S. lifetime radiation exposure limit during one round trip mission. "Even for the shortest of missions we are perilously close to the radiation career and health limits that we've established for our astronauts," NASA's chief medical officer Richard Williams told a National Academy of Sciences' medical committee on Thursday."
Radiation only has positive outcomes!
If something is so important that you feel the need to post it on the internet... It probably isn't that important.
From the article:
Current U.S. standards limit an astronaut’s lifetime radiation exposure to 1 Sievert, or 1,000 milliSieverts, which equates to about a five percent chance increase in developing a fatal cancer.
A new study shows that with currently available propulsion technologies and similar shielding to Curiosity’s, astronauts on even the shortest roundtrips to Mars would get radiation doses of about 662 millisieverts and that doesn’t include radiation dosages for any time spent on the Martian surface.
Sounds like a rather low risk compared to that of the mission as a whole.
So limit outdoor activity, and bury the colony shelters so that you can leverage inxpensive dirt for shielding.
Say, with sandbags packed with martian regolith.
(With a solar sintering machine, and "refined 19th century tech*", you could produce all the glass fiber sandbags you could possibly ever want on mars.)
* 19th century version
*refined modern and cheap consumer version
[For the imagination impaired, you use the solar sintering machine to produce a small, stationary bead of melted glass from abundant martian regolith, use a steel mandril to pull several glass fiber pulls off that bead, thread them through some eye-hooks in a halfcircle around the bead, then thread them through one last eye-hook as a bundle, and then feed the bundle into the knitting machine. Turn the crank, and a continuous tube of knitted glass fiber gets pooped out. Cut the "sock" at desired lengths, and use more glass fiber in a handheld bag stitcher to close the end, and stuff them with martian regolith. You can then stack them up to make 1950s style bunkers around the the habitat structures, which will not only keep the wind off of them, but also provide radiation shielding on the cheap for the colony. The total equipment needed would be well under 20kg, and would allow unlimited sandbag production at the colony site.]
Cockroaches can withstand radiation . . . maybe modern gene therapy could help humans to replicate that process in themselves . . . ?
Hopefully, without turning them into cockroaches . . .
Too late. We call them lawyers
I'm a consultant - I convert gibberish into cash-flow.
It's a shame so much of NASA's human exploration has been cut back.
I wish I could agree, but I can't. I hate to say it because I grew up on the manned space program. As a kid I saw Neil Armstrong take the first steps on the moon (yes, that means I'm over 21) and thought what an historic moment it was. One of the things that we learned in those early days though is that people are fragile and manned space flight is horribly expensive. For a fraction of the price (10%?) you can send an unmanned mission. Frankly a lot of the support for manned space flight is that people want to see Buck Rogers, but almost all important scientific and practical work has been done by unmanned spacecraft. Please don't respond with examples of the work done in manned space flight. I know there's been some stuff, but it's tiny compared to the cost and what's been done unmanned. Also our ability to create robots (or whatever you want to call them) has increased dramatically since the early days.
Sure we could develop some cool tech for manned missions, but there are cheaper ways to do it. We could also create some cool robotic tech for unmanned missions. Before we send anybody to Mars, let's at least do an unmanned round trip.
Never send a man to do a robot's job.
Seriously, they already know how to deal with this, and discovered that hydrogen neuclei are ideal for absorbing high energy cosmic rays, since they produce a minumum of secondary high energy particles from the interaction. This means a substance with lots of hydrogen in a small volume makes the best shielding.
This leads us to the most abundant, hydrogen dense material available, which would also be necessary for the trip, and colony operations: water.
Basically, put the crew capsule inside the water storage tank. Radiation problem solved. You have to send the water anyway. Make the most of it.
Ya, there's something that can be done. The government is being very hush-hush about it. Until now, only those "in the know" have been told.
Just under the surface of Mars is a vast quantity of water ice.
In the Cydonia region of mars, there is an ancient pyramid. Deep within the pyramid is an alien device which will turn the water ice into a Earth-like breathable atmosphere.
There is a catch though. There are agents already on-planet who will stop at nothing to keep you from activating the machine.
It would take a madman to even consider it. More specifically, a madman who's mind has already been scrambled by a dramatically failed lobotomy. That man may be you.
Serious? Seriousness is well above my pay grade.
With that kind of negativity, of couse you won't look for sensible options.
Like, using marsian weather to deposit the dirt for you, or noting that martian surface gravity is 1/3 that of earth, and that a "50lb bag of sand" will weigh only 16.6lbs on mars.
Don't let those little things trouble your already made up mind though. (Like how at that kind of mechanical strain reduction, glass fiber tethers can hold up loads that you need high grade steel cables for on earth, and all the engineering tricks this simple fact would let you get away with on mars, that you simply would be unable to do on earth in any of the other harsh environments you cited, especially the ocean floor, where you would need a habitat made of pure premium unobtanium to hold back the hundreds of tons of pressure per square meter of water overhead.)
If you approach your problems with the preconception of "Its hard, and can't be done, and isn't worth the time!", then it will never be done, even when conditions have changed, and it most certainly can be done.
The purpose of building a colony outside of the earth is NOT to solve word overpopulation. The purpose is to put our eggs in many baskets. Or did you learn nothing from the celybinsk(sp?) Meteor incident?
Life doesn't have to be fun, glamorous, easy, or desirable there. The reason for putting life there isn't to crow about accomplishments, to solve some "overpopulation problem", or due to some science fiction fantasy utopian ideology or dream. Those are all popular canards used by people who hold your viewpoint, but none of them are the reasons why we should build a martian colony.
So, why then? Ask Mr Sagan. The basic gist is that keeping all the humans in one basket (earth) is a recipie for extinction on the long term. We have had at least one mass extinction event on this world. (And likely many others.) If it has happened once, it can and eventually will happen again. Refusal to accept this as a rational reason to expand our holdings as a species in favor of petty indulgences and empty arguments about difficulty are not founded on reason. Or did the recent russian meteor event not provide enough impetus for you?
No-one is saying a martian colony will be anything but a torturous, inhospitable, and eternally drudge-infused effort to barely survive. We are saying that the adversities that would be present are not insurmountable, and that you only truly fail when you fail to try, and are offing suggestions on how those adversities could be effectively overcome.
Take your recent one: moving hundreds of tons of dirt on top of the habitat's dome of sandbags.
Here's an inexpensive way to do it, that makes use of the martian environment, rather than fighting it:
Mars has seasonal winds that blow the powder fine regolith all over the place, and routinely move huge dunes of the stuff around. You build a wind control wallaround the leeward sides of the dome, so that the dust carried by the winds gets dropped. Mars itself willdump the dirt you want if you are patient.
You can test this out in earth based deserts right now if you want. It's how lost cities in the sahara from antiquity get buried over.
When faced with a very daunting engineering challenge, don't work hard and go nowhere; work smart, and get shit done.