Mars Explorers Face Huge Radiation Problem 283
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."
Hitch a ride: (Score:5, Interesting)
Just find a small periodic asteroid going approx. the same way, or make one go the same way using the slingshot affect, bore a hole into it via robots and explosives, and then the "roidnauts" and their ship could hop in the hole when it passes by Earth.
Re:Okay (Score:5, Interesting)
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 [blogspot.com]
*refined modern and cheap consumer version [blogspot.com]
[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.]
use water (Score:5, Interesting)
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.
Re:Okay (Score:5, Interesting)
Solar sintering machine.
http://www.markuskayser.com/work/solarsinter/ [markuskayser.com]
Instead of attempting to use it as a 3d printer, you keep a fixed focal point, and simply melt the regolith into a small (US quarter sized) bead of hot glass.
You use a small metal mandril to pull glass fiber pulls off of that. The drawing of the glass shrinks the bead, but the sinter just makes more to replace it. Multiple pulls are made from the same bead, at different angles, then combined into a bundle.
Note how the 3d printer version fits in a suitcase.
Mars has 1/2 the solar irradiation as earth, so it will need a larger fresnel lens. Otherwise, same setup, minus the build table mechanics.
Re:Okay (Score:5, Interesting)
I don't care. Put me on that rock. Hell, I'll go tonight. Let's do this.
Get me there, let me walk on Mars. The rest is details, nothing that happens after taking a step on another planet could possibly ever matter to me ever again, and whatever was done, whatever was sacrificed, whatever the cost, it would be worth it. I don't care. Let's go.
Re:Okay (Score:4, Interesting)
All I'm hearing is (Score:4, Interesting)
"We'd better develop mature gene therapy soon". Cancers, aging, congenital defects, HIV, Lupus, psoriatic eczema... the list goes on and on.
Effective medicine will open the cosmos to post-humans. It's just silly to pretend we have to leave our little egg before we've developed enough to survive in the outside world.
Re:Okay (Score:5, Interesting)
The simplest solution is to use astronauts who are immune to lifetime radiation exposure.
I am serious.
An astronaut who is 65 years old is safe from radiation damage that will kill him 40 years later. He or she is relatively immune to radiation damage that would be a threat to their health 20 years down the road. Not only that, but the corps of potential astronauts is expanded to include all the women who are post menopause.
I doubt that there would be much problem recruiting astronauts from the pool of USA retirees. Since computerization has also pretty much eliminated the need for astronauts with fast reflexes, there is no reason at all not to do this.
As a possibly major fringe benefit, the possibility of aging into the USA Astronaut Corps would encourage a lot of the middle aged to fight harder against that midriff bulge. We would have a much healthier populace.
Re:Hasn't Comic Book taught you anything. (Score:5, Interesting)
So let's turn a problem into a solution. A lot of radiation, add a layered antennae tuned to the radiation to convert the energy into usable power. Nano structures can absorb and convert a lot of energy, it only remains to engineer the right one that can absorb and convert the most problematic frequencies. Often just attempting to block specific frequencies is less efficient than absorbing and converting to use full energy and then absorbing and converting to heat.