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NASA Wants Revolutionary Radiation Shielding Tech
coondoggie writes "Long term exposure to radiation is one of the biggest challenges in long-duration human spaceflights, and NASA is now looking for what it calls 'revolutionary' technology that would help protect astronauts from harmful exposure. 'It is believed that the best strategy for radiation protection and shielding for long duration human missions is to use electrostatic active radiation shielding while, in concert, taking the full advantage of the state-of-the-art evolutionary passive (material) shielding technologies for the much reduced and weaken radiation that may escape and hit the spacecraft.'"
Seems to be the first line of defence for many...
A feeling of having made the same mistake before: Deja Foobar
Tinfoil Hat thing didn't play out?
To put a witty saying into 120 characters, jst rmv ll th vwls.
Active shielding could lead to some neat side techs, as with most NASA tech. But, this being what it is, I'll summarize the next few dozen comments: (insert comment here about not wasting money on NASA when we could use their budget to take care of some rounding errors in the national debt) (insert irrelevant reference to Fukushima here) (insert comment that all NASA craft would now be indestructible with the addition of something for which the polarity could be reversed and / or to which all auxiliary power could be diverted)
Nope. Completely different type of radiation.
In space, the main problem (unless your spacecraft is nuclear-powered) are high energy cosmic rays.
In Japan, the issue is with radionuclide contamination.
Also, NASA's looking for a way to keep external radiation out - in Japan they're trying to contain radioactive substances within a vessel that contains superheated water that is pressurizing it, water which is unfortunately radioactive (resulting in the steam being radioactive if they vent it)
retrorocket.o not found, launch anyway?
A few thousand kilometers radius magnetic field and about 70 Kg/m^2 mass does the trick nicely.
As far as I remember the biggest threat to astronauts is from cosmic rays, which are charged particles and require shedloads of shielding if you want to stop them with a passive shield.
Just move the Earth wherever you want to go.
The reason, even 1st generation ones will be able to lift 2 to 3 times as much weight in orbit as the chemical rockets we have now. This is the difference between orbiting the earth with substantial protection in an overbuilt craft and orbiting with tin foil.
The simple act of wrapping the crew quarters with water tanks for one. Water, when exposed to vacuum, freezes. It expands when it freezes, sealing any holes made by micro meteorites or space junk. It absorbs radiation somewhat readily, meaning you'd have to purify it before putting it to its most common use - drinking it.
But building a spacecraft or spaceship with such a concept in place will take a monumental increase in lifting capacity. We've taken chem rockets about as far as they are going to go - nuclear is the way if we can ever get over our irrational fear of the stuff.
Neutron radiation is neutrons. The #1 neutron-stopper in use is water (or other stuff high in hydrogen).
Those who fail to understand communication protocols, are doomed to repeat them over port 80.
IIRC there was an SF story by A.C. Clark where a space craft used a huge block of ice as a radiation shield.
Alpha particles are blocked by a thin sheet of paper, so no risk to astronautics as long as the alpha particle producers stay outside the craft
Secondary gammas release on impact. Ouch.
Beta particles are neutrons
No electrons.
Gamma rays are an electromagnetic wave, like light, and hence also can't be deflected by an electric field.
There are other types of radiation, but I got the feeling they were rare (ie. not found except in particle accelerators) - can someone correct me?
Not really. nuke radiation is pretty much defined as alpha beta and gamma "waves/particles" plus our mostly artificially generated pal, the neutron. If we could make muons or other particles in bulk we'd probably add those. Delta waves and stuff are only found in star trek technobabble.
The concept of "rare" is kind of vague in particle physics.
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
And how do you suppose they'd see where they are going then? Ha? Ha? Have you thought about that?
You can't handle the truth.
The universe is a big particle accelerator. Cosmic rays are one of the biggest dangers and they're mostly protons or helium nuclei, which can certainly be deflected by electric or magnetic fields. Likewise, the solar wind is mostly protons and electrons, both of which are charged and can be deflected.
i thought Marie Curie was the first the promote it: https://secure.wikimedia.org/wikipedia/en/wiki/Marie_Curie
It's not a typo if you understood the meaning!
Find out how radiation damages cells and find out how to repair it. Awww, too hard? Better get that shit figured out before dreaming about long term human spaceflight, eh?
Is it possible that an active magnetic envelope could be devised that would capture radiation and particles at the front of the craft and accelerate it to the rear. There is not a lot of interplanetary debris, but what is there would be devastating as the craft approaches a significant fraction of c. Shielding would be necessary for both radiation and particulate matter. If the particles and ionized radiation could be harnessed, the craft could move through space much like a jelly fish.
Aah, change is good. -- Rafiki
Yeah, but it ain't easy. -- Simba
Well, I guess if you are somehow able to set up a magnetic field that circles the craft then charged particles heading towards the craft could possibly be bent around the craft without making contact. This is due to a magnetic field causing Lorentz forces on the incoming particles. However, this only takes care of particles that are heading right for the craft, i.e. normal to the body. Particles moving parallel to the body might well be snagged and sucked into the body due to the same Lorentz forces.
The other issue is generating magnetic fields is non-trivial and usually requires heavy equipment, i.e. permanent magnets, coils and iron cores. Any workarounds on this?
I think gamma rays might still be a significant problem.
BTM
That was the turning point of my life--I went from negative zero to positive zero.
This is just a random thought that I had, and I'll admit I know jack about physics. But from my understanding high energy electromagnetic radiation needs to be block by rather dense things because it increase the chance that the electromagnetic wave will collide with the atoms and be absorbed instead of pass through it.
What if there was a superconductor that was saturated with electrons, would that be effective at blocking electromagnetic radiation? I'm asking at more of a theoretical level, and I am ignoring all of the engineering problems.
Be nice, I haven't taken physics since high-school.
-An Inquisitive Idiot
Just crew the ship(s) with Japanese astronauts. ...
What? Too soon?
Yes, this rare situation is much to serious to be made light of.
Wait till it's well done before making such jokes!
People in cars cause accidents....accidents in cars cause people
With the exception of Project Orion, all of the nuclear propulsion concepts I've read about, and even the actual trials made in the 1960s, have much lower thrust than chemical fueled rockets. In the case of ion and plasma thrusters, vanishingly little thrust. Even in the case of fission/thermal rockets (e.g., NERVA), only about a third of the thrust of chemical rockets. They are less suitable for getting stuff into orbit than chemical rockets.
Once you're in orbit (or beyond), thrust counts for much less than exhaust velocity.
And as for Project Orion: Yeah, some of the proposed designs could heave a pretty damn big ship into orbit, But the fear of fallout from hundreds of little atomic bombs going off in the atmosphere is anything but irrational. One of the principles of the project, Freeman Dyson, specifically stated that the risk wasn't worth it. (I mean, maybe if there was a big asteroid on the way . . .)
And . . . jeeze:
"Water, when exposed to vacuum, freezes."
No, it evaporates.
Well, to be fair it's not the steam that's radioactive.
If they could remove the heavier elements out of the steam (perhaps by forcing it through a distillation column as it escapes?) the H2O wouldn't be an issue.
I'm taking a course right now about how to predict and mitigate space radiation effects in electronics. We may have skipped over radiation that harms humans but not electronics, but here is what I know.
The radiation you are talking about are the all result of nuclear decay. In science/engineering the word radiation can refer to any type of electromagnetic or energetic particle which is radiating from an object. Nuclear radiation generally isn't a concern in the space environment (unless you are carrying some nuclear material yourself).
The types radiation that we are primarily concerned about in space are charged particles: electrons, protons, and heavy ions (any ionized atom). Those all interact with electromagnetic fields. The fact that the earth's magnetic field has such a profound affect on radiation is why terrestrial radiation is at a much lower level than space radiation.
But while it makes the terrestrial environment nicer, the earth's magnetic shield makes the orbital environment worse, as all those charged particles that would have hit the earth either get deflected or trapped where they travel back and forth along the magnetic field lines (see Van Allen Belts) which is of course worst at the poles (see South Atlantic Anomaly).
Neutrons are also a concern, as are X-Rays/Gamma-Rays (especially during solar flares), and even UV. But the vast majority of radiation effects are caused by charged particles.
The good old MIR had a much better shielding than the Internationale Space Station. The simple reason: It was so massive with so much junk around the module. Now they want to be fancy, light, and efficient.
Fools, I say!
Once the space elevator is finally running, we might be able to go back to nice and heavy, with a lead, paraffin, moon-rock mixture.- Who knows, the first interplanetary cruiser might look like Red Dwarf.
Boooo..... hahahahahaha. no mod points left ;-(
I'm not anti-social, I'm anti-idiot.
Not really. nuke radiation is pretty much defined as alpha beta and gamma "waves/particles" plus our mostly artificially generated pal, the neutron. If we could make muons or other particles in bulk we'd probably add those. Delta waves and stuff are only found in star trek technobabble.
The concept of "rare" is kind of vague in particle physics.
Don't forget the odd decay by positron emission. (and subsequent annihilation radiation when that hits your passive shielding)
Water, when exposed to a vacuum, boils. (Slowly.)
Alpha particles = helium nucelus
Beta particles = electrons and positrons (not neutrons)
Gamma rays being EM waves, might be deflected by electro magnetics...
Some others common forms of ionizing radiation...
Neutron radiation = neutrons (you got that mixed up with beta), basically how current fission nuclear reactors chain and how C14 carbon dating works.
Proton radiation = mostly cosmic rays, but also used for cancer treatment
The problem with cosmic rays which are mostly proton radiation (but also include all the above mentioned forms of radiation and all sorts of other charged ions of various heavier nucleic isotopes and vanilla uncharged neutron radiation) is that they are HIGHLY energetic (e.g, from 10^7 up to 10^20 eV) compared the usual sources of radiation. This makes them exceptionally hard to stop or deflect. Even cosmic alpha particles won't be stopped by a thin sheet of paper.
It seems unlikely that an electro-static shield configuration would stop this stuff (from an strictly energy point of view). But maybe a "startrek" like dynamically modulated shield would have a better chance to deflect the radiation around a small volume of space where people might be located in a ship. Still, it seems unlikley that would work either (even though it would probably take less energy to diffract the radiation than to cancel/stop the stream of radio active particles, it still seems like a lot to ask).
For example, I don't think they have even solved this problem for the moon or mars where we would get protected from about 1/2 of the radiation by being on the ground (since cosmic rays from the other side have to go through the celetial object to get to us) and there isn't that much of a weight problem. In outerspace, it's coming from all sides and would be twice as bad and we have to carry it with us.
People in Hell want iced water. But that ain't gonna happen either.
The US government have made it clear that we have no inalienable rights; any we do not defend vigorously will be taken.
Didn't she die of cancer? Didn't most of those working in her lab die of cancer? I'm not sure......
All de water in Denial?
I'm trying to teach myself to set people on fire with my mind... Is it hot in here?
Shielding is primarily used to take care of the low-hanging fruit when dealing with space radiation. There are some really high energy particles out there which are simply impractical to completely block with passive shielding.
Furthermore, energetic particles do the most damage when they are low-enough energy that object they hit can just barely stop them (at the Bragg Peak), whereas very high energy particles are more likely to pass right through without interacting. If you have a relatively uniform distribution of particle energies, then additional shielding may block the lower energy ones, but slow down the higher energy ones to take their place, leaving you with a similar distribution of particles as you began with. One of my professors told me that she has even heard of rare situations where additional shielding actually made things worse through that substitution effect. Normally, after about 20-50mm of aluminum, it helps some but not enough to justify the additional launch costs.
Silly "experts! The Hindus have had active technology for a long time now.
Agnihotra: The solution to prevent effect of nuclear radiation.
http://www.hindujagruti.org/news/11560.html
This is Slashdot!
How dare you not want to send humans as soon as possible for Star Trekful fapworthy adventures despite the fact they are useless for actually "exploring" space since their function is still to operate remote systems?
"This post is an artistic work of fiction and falsehood. Only a fool would take anything posted here as fact."
I think what they are really worried about are very high energy cosmic rays, can be protons, but also can be atomic nuclei (I believe that Iron nuclei have been detected in UHECR's, for example). If these hit shielding, they will cause a shower of secondaries that would be quite dangerous (on the Earth, this happens many km up, so it's not dangerous here on the ground). It might be possible to use multiple shield with a gap, but that make for a big structure. Deflecting these away from the spacecraft would be a good idea, if it can be done.
Well, the "telerobotics" would be an issue on Mars when you figure that there will be a delay between 4 and 20 minutes. So the whole "Wait, stop! That looks interesting!" part becomes a bit trickier.
(a) Polarize the hull plating
(b) If that doesn't work, I recommend bypassing the quantum phase-modulator arrays in the plasma conduits, thereby frequency-limiting the gravimetric fluctuations in the warp nacelles and hopefully inducing a soliton static-warp shield-harmonic attenuation grid over the triassic subresonance field.
Creates a few, too. Ever tried using a mouse that took a second to start working and a second to stop?
Yes, TF2 has been laggy today... but anyway, it won't be such a problem if one can endow the robot with an intelligence on the order of, say, a mouse.
If God forks the Universe every time you roll a die, he'd better have a damned good memory.
Burns: What will you demand next? Real *lead* in the radiation shields?!
Just supply the crew with enough Rad-X and Rad-Away.
And don't forget some extra water chips, just in case.
Well, the "telerobotics" would be an issue on Mars when you figure that there will be a delay between 4 and 20 minutes. So the whole "Wait, stop! That looks interesting!" part becomes a bit trickier.
Yes, it's not like they could just turn round once and go back once they received the instruction twenty minutes later or anything.
To have a right to do a thing is not at all the same as to be right in doing it
We spend nine months in the womb, so why not fill the spacecraft with water. It sounds crazy at first, but water offers radiation protection including thermal protection, we can drink it, it makes good use of the empty space AND if the spacecraft is rotated slowly the centripetal acceleration of the water on the human body should mimic gravity. A 10m water column on earth is approximately two atmospheres, and long durations breathing at this pressure may require decompression however an appropriate sized water column slowly rotating in space should be exactly one atmosphere - no problem! It should mean that calcium won't leach from our bones, our bones won't pit or become brittle as is the normal case with pressurisation and microgravity, and we have viscous water, and artificial gravity to exercise against meaning our muscles won't waste away. Sure we need to make the spacecraft instrumentation waterproof, not that difficult, and we need to be able to breathe, but we could make an external gill or something like cave dwelling axelotyl, or make do with a rebreather. On Mars, same system just take refuge at the appropriate depth in the bottom of a watercolumn, and you won't need to spin it but will receive the same benefits! Let's try it- email pilotfever@gmail.com. On EVA consider a water presurised drysuit as the basis of a spacesuit. Put funky display units inside the helmets. Not all the spacecraft needs to be filled with water, have a submarine inspired airlock. Finish the job and include a Polywell derived IEC fusion and plasma propulsion system (that will get us to Mars in six weeks or less with a ionocraft inspired external hull for Earth based atmospheric propulsion).
Your mindless trashing of NASA is revolting. The people at NASA are dedicated professionals. I doubt you have the qualifications to mow the lawn at a NASA facility, given the shear ignorance of your statement. I assume that you trash talk you betters because you are both stupid and vile. You are most likely incapable of tying you own shoes, so your only response is to slander people who have real accomplishments.
Why is Snark Required?
She could have died of any old thing I suppose. Nobody is saying correlation =causation. I don't even know if she died of cancer since I didn't check, that just sticks in my mind for some reason.
But it is interesting if a person smokes that they tend to get emphysema and lung cancer. I suppose they could get emphysema from any old source or lung cancer from just about anywhere to.
Working with radioactive substances when nobody knew there such things might lead to radiation poisening might lead one to excess exposure. Just as working with asbestos back in the day was not considered hazardous. And people just breathed the dust in without much thought.
It is a good thing we learn things ain't it? That way we can keep from being retarded.
Why not focus on accelerating DNA/RNA repair?
It could be easier to fix than to defend our bodies.
--
On the eighth day, God created FORTRAN. Lucifer had already released COBOL.