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  (Source: TriStar Pictures)
NASA already responded to the results, saying it will conduct studies of its own

Astronauts have the ability to see planets and other space-related beings in ways most of us never will, but new research shows that astronauts could potentially lose their vision completely by living out this profession.

The University of Texas Medical School at Houston recently performed tests on astronauts who had spent more than one month in space, and found that they had eyeball and brain tissue damage.

Texas researchers studied 27 astronauts who had participated in long-duration NASA missions. Out of the 27, nine had an expansion of the cerebral spinal fluid space surrounding the optic nerve; six of them had a flattening of the rear of the eyeball; four of them had a bulging of the optic nerve, and three of them had changes in their pituitary gland and its connection to the brain.

All of the astronauts studied spent an average of 108 days in space, either on a space shuttle mission or spending time on the International Space Station (ISS). The researchers found that the issues these astronauts have are similar to those caused by intracranial hypertension, where pressure in the brain presses against the eye sockets and skull.

"Microgravity-induced intracranial hypertension represents a hypothetical risk factor and a potential limitation to long-duration space travel," said Professor Larry Kramer, leader of the study at the University of Texas Medical School. "Consider the possible impact on proposed manned missions to Mars or even the concept of space tourism. Can risks be eventually mitigated? Can abnormalities detected be completely reversed?

"The next step is confirming the findings, defining causation and working towards a solution based on solid evidence."

The study has already grabbed NASA's attention. While no astronauts are being pulled from any programs at this point, the space agency plans to look further into these results.

"NASA has placed this problem high on its list of human risks, has initiated a comprehensive programme to study its mechanisms and implications, and will continue to closely monitor the situation," said William Tarver, head of flight medicine at NASA's Johnson Space Centre in Houston, Texas.

If these results were proven true, it could throw a wrench in many space plans such as SpaceX's idea to develop a reusable launch system for cheap spaceflight and Mars settlement. There are also plans to send an astronaut to an asteroid by 2025 and another to Mars by 2030.

Sources: Phyorg.com, ABC News, The Pioneer



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Well.
By Amiga500 on 3/14/2012 9:34:06 AM , Rating: 5
I guess that means we'll just have to induce "artificial gravity" on any new long-term manned space installation.

A more pertinent question might be - is the moon's gravity sufficient to prevent these eye problems occurring, or will any moonbase require complex construction to induce the effects of gravity?




RE: Well.
By dajeepster on 3/14/2012 10:00:39 AM , Rating: 2
i don't know why someone downrated you... you have valid points.


RE: Well.
By MrBlastman on 3/14/2012 10:55:31 AM , Rating: 4
Good points yes but I think there are others to consider also. What we have here is a study with results and a proposed causative source inducing a less than desirable effect on the human body. The easiest answer here is we need artificial gravity... on paper.

One other idea to consider is this. The study mentions that hypertension is causing these changes in the optic nerve/eyeball etc. But why? Why would it do this? Well, think about it. Strap your ankles to a coatrack and hang there for some time. I can assure you that pressure will build up in your head and eventually you might pass out.

What we see here is how gravity helps us regulate the pressure in our skull. Man is accustomed to being upright or laying down, constantly being effected by gravity. When we are sleeping it is not so much an issue as our blood pressure naturally drops when gravity is not pulling as much blood to our feet (thus reducing pressure in our head), so, it counterbalances our waking hours.

When awake and active, gravity acts on the blood and keeps it from traveling to our heads with as much force versus our feet. When a fighter pilot, for instance, pulls extreme G's, they black out because too little goes to their brain, thus the inception of G-suits and 30-degree reclining seats to assist in preventing this.

When man is in space... there is no gravity to act upon the body and bloodflow, thus, pressure is not regulated by this natural mechanism--increasing total pressure in the brain. You see, as it seems (with limited data) that a short-term, more elegant solution would be... blood pressure medication! I believe the studies should continue by having astronauts pop beta blockers and other drugs to help reduce pressure while in space so we can see if there is any benefit to this. I theorize that there will be... and in the short-term, alleviates the need for artificial gravity (which with our current technology... is very primitive in potential).

Going to Mars... I'm not so worried about. Put the ship in a 1 G burn, orient the cabin layouts to have astronaut feet on the "ground" of this and it will seem like they are on earth... fuel is an issue, though...


RE: Well.
By ppardee on 3/14/2012 2:52:44 PM , Rating: 2
While I appreciate your desire to find a simpler solution, drugs aren't the answer, especially for long-term trips. Hypertension medication has side-effects. Trying to fix one problem by introducing another is not advisable. Secondly, having the crew take drugs every day means you have to have the drugs on board. This means a higher launch weight, greater inertia (lower maneuverability) and less space on the ship. Related to that, what happens when you run out of the medication?

Gravity can be simulated via centrifugal force. A cylindrical capsule can be spun, creating "downward" force against the sides of the capsule. The down side here is that it limits the design. The upside is varying gravity is as easy as spinning up/down the capsule, and maintaining gravity should require little/no power since there is little/no drag on the capsule itself. Have the crew sit on the end of the capsule for launch (so they are upright on Earth) then once they've had enough of weightlessness, they can spin up the capsule. This would also have the benefit of offsetting the atrophy associated with long-term weightlessness.


RE: Well.
By MrBlastman on 3/15/2012 1:05:04 AM , Rating: 2
You're missing a few things... I'll elaborate. :)

quote:
Hypertension medication has side-effects.


They are small. Have you ever been on beta blockers? I am and not for high blood pressure.

quote:
This means a higher launch weight, greater inertia (lower maneuverability) and less space on the ship.


Not that much. We're talking pills here. Beta blockers are quite light weight, I can assure you that. As for inertia... minimal effect at best and not even worth mentioning.

quote:
maintaining gravity should require little/no power since there is little/no drag on the capsule itself.


Nope. You forget this little thing called the people inside touching the walls and manipulating objects within. For every action there is an equal and opposite reaction. While it might be small, it is parasitic to a degree. Some form of maintenance of the speed is required.

Also, many studies have been done on the coriolis effects of rotational artificial gravity and they can be significant. The RPM of the rotation can not exceed 2 RPM thus requiring a 735 ft radius of rotation--a LARGE ship! This problem is costly and complicated to solve by just saying, "hey, lets do artifical gravity!" The cost of materials to put a craft/parts into orbit to accommodate these needs far outweigh the costs to put some pills into orbit.


RE: Well.
By niva on 3/14/2012 6:49:20 PM , Rating: 2
A sustained 1G burn to Mars would get us there in days... Obviously somewhere halfway through you'll have to turn this around and start breaking at a sustained 1G, but what I'm trying to say is that right now with our technology this is not feasible at all.

Assuming 9.8 m/s^2 acceleration within a day (86400 seconds) starting from 0 velocity you would have traveled well over 300k km.

http://www.wolframalpha.com/input/?i=integrate+9.8...

At a sustained acceleration of 1G at the end of 1 day you're moving at ~8000 km/s which is faster than any human has moved up to this point in history that we know of relative to the position of our planet.

We have no such energy source available in space right now, to accelerate a massive spacecraft filled with people, so that we could produce such long term acceleration.

So 1G acceleration is ludicrous to talk about at this stage. Artificial gravity is also ludicrous because we cannot yet build such big structures in space that would make this possible unless we stop all wars and dedicate ourselves towards conquering our solar system at least.


RE: Well.
By MrBlastman on 3/15/2012 12:56:48 AM , Rating: 2
Hence why,

quote:
fuel is an issue, though...


The information is in the details. I choose my words carefully and deliberately so it is easy to overlook things I say. ;)

This gets back to my first point--beta blockers and blood pressure medication. It might just work as a holdover to better solutions.


RE: Well.
By JediJeb on 3/15/2012 4:04:35 PM , Rating: 3
I have been on beta blockers in the past and am on blood pressure medicine currently, and not all of them would relieve this problem. Beta blockers work by controlling heart rate, which probably would not fix the problem mentioned in the article. Also the article talks about hypertension within the brain cavity, not the entire circulatory system. This problem arises from the fact that in a weightless environment the body's internal fluids tend to flow up into the upper body. Think of how sitting for long periods no earth can cause swelling in the feet and legs, in space it is the opposite effect, your chest and head "swells" or fill with fluid. To remedy the problem we need to find a way to keep things like lymphatic fluids and blood lower in the body under weightless conditions. I'm not sure we have drugs yet that can accomplish this.


RE: Well.
By Reclaimer77 on 3/14/2012 10:02:10 AM , Rating: 2
I like your line of thinking. Next we need to quantify exactly how much gravity is needed to prevent this tissue and nerve damage. My gut tells me the Moons gravity should be enough to keep those fluids from building up and everything flowing to where it should be. But I'm not a doctor and that's just a guess, we really need to find out.

Of course at our rate I fear moon bases and long term space exploration will remain the stuff of science fiction lore for generations to come.


RE: Well.
By Kurz on 3/14/2012 10:09:34 AM , Rating: 2
We are just not built for space...
Genetic engineering maybe the only way for us to adapt to the harsh realities of space.


RE: Well.
By Reclaimer77 on 3/14/2012 10:22:52 AM , Rating: 2
That's the great thing about humanity in it's current form. For the first time on Earth, a species has evolved to the point that they have the mental capacity and scientific understanding to bypass, or even affect, the evolutionary process.

We can shield ourselves from it's radiation. We can induce gravity through centrifugal rotation or other means. We WILL conquer space. That's what man does. We overcome, we adapt, we survive.


RE: Well.
By theapparition on 3/14/2012 1:01:13 PM , Rating: 4
But now we know exactly why all those space aliens have glass domes over their brains. Seems they've already conquered hypercranial tension.

Damn Martians were smart.


RE: Well.
By LSUJester on 3/14/2012 1:09:54 PM , Rating: 3
"We come in peace."

ZAP


RE: Well.
By JediJeb on 3/14/2012 2:14:10 PM , Rating: 3
If only they could fix the issue it causes when hearing Slim Whitman. :)


RE: Well.
By Reclaimer77 on 3/14/2012 4:04:55 PM , Rating: 1
Ah ha! And that's why Grey aliens have those huge black eyes! They're immune to this tissue and nerve damage from evolution!


RE: Well.
By MrBlastman on 3/14/2012 11:01:08 AM , Rating: 2
You can't genetically engineer away the effects of gamma rays and x-rays on our bodies. At least, not without completely changing our chemical-based structures. If we do that, we might cease to be human. It'd probably be better at that point to use robot surrogates instead. We are who we are. I'm pretty sure there is life outside of Earth, however, that has completely different processes (and to us might not seem biological at all) that can withstand these things.

I scoff at us not being built for space. Our only problem is we haven't built what we need for space, yet. If man doesn't kill themselves off, we eventually will. The issue with that, though, is we're already in a horse race competing against that. Who makes it around the track first remains to be seen.


RE: Well.
By Kurz on 3/14/2012 11:18:55 AM , Rating: 2
You can engineer how our cells repair ourselves, how the various mechanisms need to be changed so its not so reliant on Gravity to function.

What causes cell death is usually the DNA getting damaged beyond repair. The most ancient and simple life has it figured out, just need to figure it out for complex organisms.

The added weight and energy required will be so high its not feasible I believe, It'll be a combination of both technology and genetics.


RE: Well.
By geddarkstorm on 3/14/2012 12:32:25 PM , Rating: 3
Actually, we could engineer extreme resistance to radiation of all forms, in theory.

Deinococcus radiodurans is a soil dwelling gram positive bacteria that can survive, without any apparent loss of colony virility and life, over 6 kGray (6000 Gray) of radiation. For reference, a human will die in 14 days if exposed to ~15 Gray of radiation, and a Neutron bomb air burst gives off ~1 kGray of radiation.

If we had a nuclear war that covered this whole planet, Deinococcus wouldn't even notice.

How does it do it? Through incredible repair mechanisms that use most of the features that are already in E. coli (which can survive up to 200 Gray of radiation). In fact, it seems mostly due to one double stranded DNA break repair protein that's key to its resistance. It also seems to hoard more Manganese than normal, which apparently protects proteins from ionizing damage, thus keeping the repair proteins alive to fix things up.

So, it is well within the realm of biology to give you the ability to survive space, and even the radiation of a nuclear blast. How do we port this to humans? Utterly unknown and no idea. The eukaryotic chromosomes are far more complex than prokaryotic. But that potential is there.

But if we could engineer this, we'd still be human, as it'd just be the addition of or a tweaking of a few of our repair enzymes and metal homeostatic transporters, nothing major. Still makes me squeamish to think of genetic engineering at all, as that's such a painfully slippery slope, and it's so easy to screw over genetics.


RE: Well.
By Reclaimer77 on 3/14/2012 2:39:18 PM , Rating: 2
I vote we just develop energy shields ala Star Trek before we start monkeying around with genetic engineering. Ships and habitats will have to be shielded from radiation anyway, so I see no benefit in going to those extremes and hacking on our genomes.


RE: Well.
By geddarkstorm on 3/14/2012 3:45:41 PM , Rating: 2
I concur completely.

A magnetic shield like our planet would protect ionized cosmic rays. Then all you need is a double layered hull with a gamma/x-ray absorbent layer between, and voila, radiation shielded just as well as our planet, if not better (depending on technological wonders). The energy from the gamma/x-rays being absorbed could even be used to help run the magnetic shield dynamo.

Considering the low Gauss rating of our planet's magnetic field is below that of a weak refrigerator magnet, it shouldn't take that much power to make an equally strong field for a small space ship.


RE: Well.
By Kurz on 3/14/2012 6:03:33 PM , Rating: 2
Only issue is that the Magnetic field of the Earth is huge. Which allows the weak effect the magnetic field to displace that radiation slowly over a long stretch of space.

Though it would be interesting the see the energy required for the similar effect... Though I bet it is much higher than you think.


RE: Well.
By geddarkstorm on 3/15/2012 1:38:31 PM , Rating: 2
Oh, actually I misspoke. The Earth's magnetic field is only 0.25–0.65 gauss at the surface of the poles (where it's strongest), while a refridgerator magnet is around 100 gauss. The field at the core of the Earth hits about 50 gauss, which is why I was thinking of "weak refridgerator magnet". In truth, the field that protects us is vanishingly weak.

Remember, a space ship is not the size of Earth, nor does it need anywhere near the same size of field. See http://www.sciencedaily.com/releases/2008/11/08110... where it was demonstrated that a magnetic bubble of only a few 100 meters across would protect a ship from solar wind and cosmic rays, making a trip to Mars safe and possible (in that regard).

Also, simply increasing the immediate intensity would be enough and allow a smaller field. That is, a surface skin field of 50 gauss would deflect pretty much any cosmic rays. There in, the total power to generate the magnetic field is easily doable (I work with a 14.6 Tesla super magnet, or 146000 gauss. Being super conducting, it takes no energy to maintain, and certainly didn't take that much to energize in the first place), and with super conductors, would require NO constant input of energy, just an initial energization.

Magnetic shields are a piece of cake to make it appears, the problem is what they will do the ship and its electronics themselves, as it'll put strain on the whole vessel by pulling it inward or outward towards the source of magnetization. So, a ship would have to be designed with it in mind. Definitely something we could figure out, as we are already working on it.


RE: Well.
By JediJeb on 3/15/2012 4:11:16 PM , Rating: 2
One problem to overcome would be the effect of the poles of the magnetic field funneling the cosmic rays/solar wind inward, which is what causes the Norther Lights during periods of solar flares. You wouldn't want crew near the poles of the magnetic field for fear of blasting them with a beam of the very radiation you are trying to protect them from.


RE: Well.
By niva on 3/14/2012 6:56:36 PM , Rating: 2
We have not evolved properly to survive 0G for extended time in our current form. This doesn't mean that if you place humans in space for a lifetime that these creatures will experience the negative effects discussed in the article. Our heads expand, limbs and spine shrink, bone density goes down... this is only a problem if you're planning on coming down. The study does not go into how these symptoms affected the astronauts while in space.

If we ever get to a point where humans are born and live out their entire lifetime in space, they would probably look vastly different from what is considered normal now. The key is that our bodies adapt to the environment. This study shows an adaption which has negative consequences in the environment the astronauts returned to, but doesn't go into the actual impacts of these adaptations in space.


RE: Well.
By Amiga500 on 3/14/2012 11:14:34 AM , Rating: 2
quote:
But I'm not a doctor and that's just a guess, we really need to find out.


Damn it Jim, I'm a doctor!


RE: Well.
By Reclaimer77 on 3/14/2012 2:54:06 PM , Rating: 2
RE: Well.
By geddarkstorm on 3/14/2012 12:37:55 PM , Rating: 2
Microgravity is definitely better than no gravity, so I'd also hazard a guess that the Moon's gravity would be enough to avoid some of these major changes. The body just needs that constant resistance to keep its systems vigilant. Now, you'd still lose muscle and bone mass, but never has badly as a zero gravity environment (or free fall).

On the other hand, there are potential pharmaceuticals that can help, such as resveratrol which was shown to keep rats from losing bone or muscle mass (or having these other negative effects) when held in a microgravity simulation experiment (hanging from tail). So, all we need is to keep the body's triggers active for maintaining its physique; otherwise without a stimulus it begins to relax to conserve energy, and hence degrade.


RE: Well.
By joedon3 on 3/14/2012 9:58:18 AM , Rating: 2
Valid points. But I also think that over time we will adapt to lower gravity environments. Just hope it doesn't take several generations to adapt. :-P


RE: Well.
By drycrust3 on 3/14/2012 10:46:35 AM , Rating: 2
When I was young space stations of the future looked like a wheel, which rotated so as to create an artificial gravity on the outside, and with a weightless environment in the "hub".


RE: Well.
By ClownPuncher on 3/15/2012 4:00:49 PM , Rating: 2
iHub. Apple patent, space is now a closed system.


RE: Well.
By TSS on 3/14/2012 1:13:22 PM , Rating: 2
Sounds to me it's a purely atmospheric problem.

Now i'm no scientist, but i can remember from my highschool biology book that the only reason we have the size that we do is purely due to atmospheric pressure. The air and fluids in our bodies are constantly pressing outwards. The only reason we don't explode is because there's atmosphere all around us pushing back. Well, to oversimplify the process.

Maybe the sollution is simply increasing the atmospheric pressure in which astronauts live. Basically turning space stations into those pre-diving tanks divers stay in before they go to work at great depths.

I'm not informed as to the atmospheric pressures in the ISS. But maybe they're just sea-level pressures, because we figured thats the atmosphere we always live in and it's worked so far so hey, why not. As well as atmosphere being rather...rare in space.

Of course we'll going to have to make the leap to artificial gravity sooner or later. I don't think we can use any plotkai like the star trek's "look we found a antigrav belt from a really ancient race" either, so it's going to be tough getting it right. Until that time, i'd say increase the pressure.

Could still be space-radiation though. That's also still an issue if we head for mars.


RE: Well.
By geddarkstorm on 3/14/2012 2:29:04 PM , Rating: 2
Actually, we don't explode because we are a contained vessel. It's the same reason why you won't "pop" if you suddenly get thrown into space. Your blood is stuck within the elastic confines of your arteries.

The only danger from rapid decompression (especially when we're talking about extreme pressures such as deep diving depths, not going from 1 atm to space) is that gasses in your blood will outgas from solution, creating bubbles (at high pressures too much gas is forced into your blood through your lungs, beyond its capacity to hold at lower pressure). Those bubbles can rupture blood vessels, aka the bends; and if done rapidly enough will blow out your lungs, ending things very messily... But your blood itself is not affected by pressure changes much (similarly, liquid water does not change volume much in response to a wide range of pressures when contained).

Consequently, more pressure on the space station may not do anything helpful. But it's still an interesting idea. Most of the problems we see are from edema, where fluid is incorrectly regulated by the body after long periods of time and starts to build up, instead of being processed out in your waste. It's like a massive case of inflammation, just without the immune response (as far as I know).


RE: Well.
By tamalero on 3/15/2012 11:26:54 AM , Rating: 2
I wonder; does the study said if the problems were caused by the lack of gravity, or from the rocket blastoff vibrations?

remember when they blast off to the ISS, they suffer higher G's than normal, and a huge bunch of vibration all the way.


"The Space Elevator will be built about 50 years after everyone stops laughing" -- Sir Arthur C. Clarke














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