Prevention is better than cure.
If the ISS had a gravity generating spin and thicker shielding, I assume the bloods would come back more normal. Shame they cancelled this bit. https://en.wikipedia.org/wiki/Centrifuge_Accommodations_Module
A new study analyzing the blood samples of 18 Russian cosmonauts reveals that space sends the body’s defensive immune system into overdrive. Space is bad for your health. The lack of gravity and the constant bombardment of radiation particles makes the environment treacherous. Numerous studies have shown astronauts …
A testing centrifuge won't do the job. In fact to do the job requires that the moment arm be long enough to avoid messing up people's sense of balance. Turns out that anything above 1 rpm starts to affect people, and beyond 3 rpm it's not good. Lest the ISS become a "vomit comet" for real, for even half a gee the wheel needs to be pretty big. Even just a couple of bucket-habs on cables is going to be pretty big.
There's a handy site to calculate this, and a one gee wheel at 1 rpm has an 894 meter radius. Even 0.5 gee at 2 rpm is a 111 meter radius. So any useful ISS enhancements designed for centrifugal gees is going to be rather involved to get up and running.
Like your working Big John and I appeciate the costs involved in such a huge component.
The Accommodation module could be 900m across and have thick shielding round its outer cylinder. If the cosmonauts lived in that module the majority of the time at 1g it would propably improve the situation. Ambitious to do I know, but we need to develop safe long term environments in space if we are going to progress.
Shielding doesn't just have to be metal, we can look into the ablative, reflecting and absorbing properties of other materials like plastics or minerals. We just need to spend some more money on looking. Magnetic shielding even? http://physicsworld.com/cws/article/news/2008/nov/06/magnetic-shield-could-protect-spacecraft
This may require some refinement (to say the least). The human bodies are not very keen on very strong magnetic fields. Ditto for a lot of equipment. There is also the issue of powering the superconducting coils. Let's face it - if it is on an outward trip (to Mars and further away) the ship will need nuclear power as well.
"This may require some refinement (to say the least). The human bodies are not very keen on very strong magnetic fields. Ditto for a lot of equipment. There is also the issue of powering the superconducting coils."
That's not so much of a problem, shaping magnetic fields is pretty trivial, so it would be easy to design a system that had the external field required while keeping the field inside close to zero.
As for powering superconductors, firstly they're talking about fields of around 1 T to block the solar wind, which could be done with permanent magnets and no power required at all. But more importantly, the thing about superconductors is that they don't actually need a lot of power to run. Zero, in fact, by definition. Superconducting magnets on Earth require a lot of power because it's hard work to keep them cold; in space that's fairly trivial, and there are plenty of satellites and probes already using cryogenic cooling with no need for nuclear power to be involved.
"Shielding doesn't just have to be metal, we can look into the ablative, reflecting and absorbing properties of other materials like plastics or minerals."
We've already looked into such things plenty. Indeed, simple concrete is very popular for radiation shielding in places where you can just stick a big wall up and not have to worry about things like size and weight. The problem is that radiation doesn't particularly care what the material used is, it's all down to how many atoms there are in the way and how big those atoms are, ie., how likely a given particle is to actually hit something. A less dense material with smaller nuclei needs a much greater volume to give the same shielding, and the overall mass will be pretty much equivalent*.
As for magnets, there's certainly potential for shielding from lower energy particles such as those in the solar wind, but as that article notes it's really not feasible for stopping higher energy particles. Higher energies mean stronger magnets are needed to make a significant difference to a particle's direction; there's a reason the LHC is 26 km long, and that's with some of the best magnets we're capable of making. Hence the final quote:
"Getting in a tin can with a rocket on your back and flying to Mars is never going to be a safe thing to do"
* Collision cross-section doesn't scale linearly with nucleus mass, so the total mass would likely be a bit smaller.
Apparently it has to do with normal head turning in relation to the constant turning of the hab, producing odd interactions within the inner ear. Precession and such. Makes me nauseous just thinking about it.
Some research suggests people can get used to it below some critical level, but that level hasn't been pinned down very well so far.
Any ground-pounder with any chance of battlefield survival knows about up and down, in addition to check-six. Any naval officer better have that imprinted on the inside of your eyelids. It has been my displeasure to learn both as I have this funny sense of self-preservation.
Which is why I didn't buy that sequence in ST:Wrath of Khan.
I think that we'd have to check that assumption before investing (hugely, as others have pointed out) in gravity-substitutes. Maybe it's the zero-g, maybe it's the radiation sleeting through the body, or circadian rhythm disruption, or angst about being separated from the rest of humanity ...
A decent test would be to set up a hostile radiation environment on the ground at 1 g, and keep the subjects in it for six months, with regular blood tests.
Volunteers, one pace forward!
"If the ISS had... thicker shielding"
Oddly enough, thicker shielding doesn't necessarily help, and can actually make things much worse. High energy particles tend to pass through things without depositing much energy in them; you're generally better off not getting hit by them, but as long as there aren't too many they probably won't do too much damage. If you put a lump of metal in front of them, instead of a single particle with very high energy, you now get a big shower of lower energy particles, resulting in much more of the energy being dumped in a shorter distance. Unless you make the metal thick enough to actually absorb the whole particle shower, probably meaning at least a couple of metres depending on the exact metal and the composition of the radiation, you can end up harming the people inside much more than if they were effectively unshielded.
"If you put a lump of metal in front of them, instead of a single particle with very high energy, you now get a big shower of lower energy particles, resulting in much more of the energy being dumped in a shorter distance".
Rather as blowing up a threatening comet head turns a single high-velocity rifle bullet into a massive shotgun blast.
When dealing with physics, common sense is often quite deceptive.
"Rather as blowing up a threatening comet head turns a single high-velocity rifle bullet into a massive shotgun blast."
And lest anyone thnk "but then the chunks will burn up in the atmosphere", check the simulations at https://craterhunter.wordpress.com/a-different-kind-of-climate-catastrophe/
tl;dr: If there are a string of fragments, then you're going to have a _very_ bad day. Possibly even worse than a single impacter.
Entropy always wins, and the longer it plays, the more it wins. Practically, that means in a contained, long-duration environment, every chemical in that system will inevitably become part of that environment. This includes things like life-support chemicals, scientific experiments, and working fluids for the electrical/mechanical/thermal systems. Proactively taking measures to prevent the development of allergic reactions to these sources- before they are inescapably stuck in a pod with them for months or years- will probably save lives.
That wouldn't have been large enough to let astronauts experience more than microgravity, though, due to its small diameter. II'd love to see something like, say four Bigelow B330 units such that two form a cetral axis, with two on cables at right angles, spinning around the central axis. Use one of the two outer B330;s for plant experiments, and teh other for human experiments. Rig 'elevators' to transport astronauts from teh core two modules to the outer two. Not entirely sure whether that'd be dynamically stable, might need three or fout units out on cables, instea dof two, but you get the idea. You would, of course, ensure that each B330 unit had plenty of emergency supplies and an emergency 'scooter' so that if something bad like a cable snapping happened, folk in teh outer modules could get back to teh spoke modules, which could, if need be, be detached from teh rest and allow teh astronauts to await rescue.
Well, is the problem the lack of gravity accelleration or is it due to the radiation?
You forgot the other three possibilities:
- It could be due to the simultaneous lack of gravity and presence of the radiation
- It could be due to another factor altogether, not considered in the present study (e.g. the diet, or the presence of chemical contaminants from the life support systems, or ...)
- It could be the result of undetected sample contamination and/or spoilage
Science is fun, but it's hard to do right and any conclusions you reach are always provisional.
"Well, is the problem the lack of gravity accelleration or is it due to the radiation?"
There must be a number of possibilities including stress. A start might be a comparison with blood chemistry of groups in other extreme & stressful environments - off the top of my head :-
Scientists resident for long periods in the Antarctic
Submariners esp. nuclear subs.
Round-the world yacht racing crews.
Tour de France cyclists ( now their blood chemistries might tell a tale )
No self respecting CMDR piloting anything smaller than a Anaconda should be using a Docking computer... besides, you don't need to go to Lave for it... there are 8 Stations in the Sol system that sell them... details here :- https://eddb.io/station?m=890&i=1&r=17072
N.B if you are an E:D player, and find yourself without fuel, shutdown all modules apart from Life Support, and contact The Fuel Rats :- https://www.fuelrats.com/i-need-fuel/
Actually I thought about this and it seems that part of the problem is that internal changes can be caused by a sterile (or very low bacteria) environment.
If so then simple custom probiotics might solve many issues, also using magnetic fields seems to help somewhat.
It may be that you only have to expose some of the body to gravitational acceleration and if so then this reduces needed field strength by an order of magnitude, within the range of permanent magnets.
Biting the hand that feeds IT © 1998–2019