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Bone density, eyesight and cancer are a few issues to be addressed

Space is no place for humans according to a recent article by The New York Times, but doctors and researchers are attempting to solve health-related side effects caused by extended trips in space. 
 
NASA has been talking about sending astronauts to Mars come 2030, which entail a 2.5-year mission. This is nearly six times the current standard tour of duty on the International Space Station (ISS). In fact, the longest amount of time any human has left Earth was 438 days, accomplished by Dr. Valery Polyakov on the Russian space station Mir in 1994 and 1995. 
 
The Mars mission will be the longest yet, certainly for any American astronaut. In preparing for such a trailblazing adventure, researchers are trying to resolve past medical problems experienced by astronauts who have been in space for much shorter time periods. 
 
The problems, according to researchers in the NYT article, are mainly caused by the lack of gravity (short-term effects) and exposure to radiation (long-term effects). 
 
For instance, the weakening of bones is a troubling issue that scientists are addressing. Without gravity, astronauts' bodies don't need to support their weight, which affects bone density. In fact, NASA researchers estimated a decade ago that astronaut bone density was decreasing by 1 to 2 percent per month. 
 
But scientists have found that strapping astronauts to treadmills and having them run helps with such issues. Osteoporosis drugs have been used as an aide as well. 


[Image Source: Warner Bros. Pictures]
 
It was noted, though, that formation and destruction occur at accelerated rates, which means scientists don’t know if an astronaut's bone is as strong as when they left. 

Eyesight changes also need to be addressed, but researchers haven't found a real solution to this yet as they did with bone density. Just five years ago, NASA scientists found that the eyes of astronauts appeared to be "squashed" after time in space. They saw hints of swelling in the optic nerves and blemishes on the retinas. 

NASA believes this is caused by the shift of fluids in the body moving upwards toward the head and chest, and the higher pressure of the cerebrospinal fluid in the skull pushing on the back of the eyeballs. 

However, this has not yet been proven and there are many questions remaining, such as why it usually affects the right eye more than the left, and men more so than women.

Life without gravity in space can also affect the body’s neurovestibular system, which tells people which way is up. Scientists have thought about using artificial gravity to relieve such problems, but this could lead to issues with the mission -- such as an accident with the spacecraft. 

Radiation is another problem, since it raises astronauts' cancer risk. NASA typically doesn't allow the lifetime cancer risk to be raised by more than three percentage points, but 2.5 years is a long time and could very well pass that point.

It's also been found that the amount of radiation humans are subjected to in space has been affecting the brains of mice in similar studies that try to recreate that environment. The mice were slower when traveling mazes than those not exposed to that amount of radiation. 

NASA will be watching and testing solutions on Scott J. Kelly, an American astronaut who will head to the ISS for a year in 2015. The agency will keep an eye on his health status before, during and after the trip in an effort to see how an extended time in space will affect him -- which could help determine solutions for the 2030 Mars trip. 

Source: The New York Times



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forgetaboutit
By alu on 1/29/2014 5:19:19 PM , Rating: 1
Unless they create a mini Earth (meaning artificial gravity and magnetic shielding from radiation) a trip to Mars is just a pipe dream.
They are all aware of the risks which is why they plan such missions well into the future when no current scientist/politician would be accountable.




RE: forgetaboutit
By Etsp on 1/29/2014 6:43:18 PM , Rating: 2
"Artificial" gravity wouldn't be too difficult, just design the craft that they'll be in for the long-haul to be a large ring and apply (and maintain) rotation to it.

The radiation shielding is still a major hurdle, as are the logistics of getting that ring-shaped ship into orbit.

Those issues are not impossible to get around though, just very difficult/expensive.


RE: forgetaboutit
By frelled on 1/29/2014 8:44:49 PM , Rating: 3
It would be difficult from a physics standpoint. The object rotating would have to be extremely large to keep you from falling over due to the rotation. The only reason we don't feel rotation on earth is due to the large diameter of the earth vs our very small size. It is unrealistic to create a system large enough for this to actually be an effective method of creating artificial gravity.


RE: forgetaboutit
By Samus on 1/29/2014 9:32:28 PM , Rating: 2
I think it's pretty obvious to everybody that sending an astronaut to Mars by 2020 will likely be a one-way trip.


RE: forgetaboutit
By Etsp on 1/30/2014 8:47:02 AM , Rating: 2
http://en.wikipedia.org/wiki/Artificial_gravity#Ro...

It would need to be 224m in diameter to hit 1g at 2rpm, and it's theorized that at 2rpm and below humans would not be able to feel the effects of the rotation.

In the grand scheme of things, 224m is perfectly possible. But again, very expensive.


RE: forgetaboutit
By jRaskell on 1/30/2014 9:02:46 AM , Rating: 5
It doesn't have to be a ring. A Pod at one end of a ~440m post with the necessary balancing counterweight at the opposite end (or even another pod) could be rotated to provide the same effect.

Hell, doesn't even have to be a post. A cable of sufficient strength would work just as well, it would just require better control mechanisms to maintain the system since it wouldn't be a fixed body.


RE: forgetaboutit
By niva on 1/30/2014 5:32:46 PM , Rating: 2
For trips to Mars we don't need "artificial gravity", or large complex rotating spacecraft. Astronauts can maintain their bone dansity via exercise as the article above stated for the few months of inter-planetary flight.

The truth is that reduced bone density only becomes an issue when you come back to Earth. If we are to be successful as species some day humans will be made, born in space, and live their entire lives out in 0g. They'll be tiny little humans with giant heads and big eyes, kind of alien looking...

Radiation protection is a concern though, again this is not necessarily as much of a concern as a trip to Mars, but once we start going outside the solar system protection from cosmic rays becomes a major problem. IMO that may be overcome by use of giant magnetic fields which is what we would be using in ion propulsion engines anyways... still, even with that it will be a problem. Major protection from interstellar radiation is actually the solar wind first, sun and earth magnetic fields, a huge atmosphere on the earth, and still some get through.

Nobody said it was going to be easy.


RE: forgetaboutit
By delphinus100 on 1/30/2014 8:53:51 PM , Rating: 2
quote:
If we are to be successful as species some day humans will be made, born in space, and live their entire lives out in 0g.


This is fine, until you want to do something down in some significant gravity well, use high-G aerobraking/aerocapture, or ride a high-thrust rocket engine.

And sorry, some of us want to go, but don't want to be colonists, we want the round trip.

Better propulsion is the key. Anything that shortens mission time, reduces all your physiological (including solar/galactic cosmic ray) issues...which brings us back to people who can tolerate serious (and for space-born, even one Earth gravity will be serious) acceleration.


RE: forgetaboutit
By Nexos on 1/30/2014 10:59:41 AM , Rating: 2
What about Coriolis forces and the gyroscopic effect a rotating mass such as this would have on attitude control?

I think it would make sense to use a pair of counter-rotating rings (masses) on every primary axis of the spacecraft. Counter rotation would negate any torque applied to the craft from friction, while changing the speed of rotation of any ring could be used to control the attitude of the craft, in effect using the rings as reaction wheels.


RE: forgetaboutit
By unimatrix725 on 1/30/2014 1:15:47 PM , Rating: 2
Yeah lots of SciFi shows have a "Habitat Ring". Gene had most of space right in my point of view. It wouldn't be easy for a moving ship to have gravity, however a stationary platform would be easier. Im not an engineer or physicist either. I think our best option in regards to what poster said. Would be to make a craft assembly line on Mars. The gravity is lighter there and fully abundant in metals. The most useful ones can be mined directly from the top crust. It would be a win / win.


RE: forgetaboutit
By Jeffk464 on 1/29/2014 7:17:50 PM , Rating: 2
You could always bio-engineer humans to do well in space.


RE: forgetaboutit
By HostileEffect on 1/29/2014 11:41:35 PM , Rating: 3
By then, I foresee humanity being cybernetic or fully synthetic by then, GE will be a footnote. Humans will be in three groups: full synth, genetically enhanced, and eco-nut purists.

I'm waiting for superior body modifications to come around in 40-60 years and if I can't get kill-switch free upgrades from a doctor, then I'll get em else where. Tbh.

IMHO, the human body is a broken, crippled "good enough" design and it is LONG OVER DUE for being fixed.

Off my sci-fi box now, I'm log over due myself for some fracking sleep. Coaching monkeys with rifles from 3AM to 5PM and its miserable doing it day in and out non stop.


RE: forgetaboutit
By sparkuss on 1/29/2014 8:57:57 PM , Rating: 2
Aren't all those issues dependent on the purpose of the mission?

Is the primary purpose just to validate human space travel to the first planet beyond Earth? Or is the trip to get there and land and determine things about Mars that only a human could determine?

By 2030 might we have robots/droids that could viably explore Mars and provide answers that only human landing could provide?


RE: forgetaboutit
By DennisB on 1/30/2014 7:07:34 AM , Rating: 2
If you take "Mars One" as an example for such a just-get-there one-way-trip a 25% survival rate on arrival on the surface is enough. No need for any elaborate safety measures. With plenty of volunteers no problems other than the cost of sending.


RE: forgetaboutit
By ShaolinSoccer on 1/30/2014 10:47:10 AM , Rating: 2
You put a lot of trust into suicidal "volunteers".


RE: forgetaboutit
By DennisB on 1/30/2014 1:03:53 PM , Rating: 2
With 78000 registered volunteers within the first two weeks. No need for faith here, there's no limit to volunteers.


RE: forgetaboutit
By lyeoh on 1/31/2014 3:06:58 PM , Rating: 2
Would be better if you could vote people off the planet- with one way or return options ;) - they are given the option to either not go or buy their own return trip if they win one way). Or it could just be "for fun" and not for real. I might be willing to spend a buck to vote just to see the interviews of the winners...

The next reality TV show - Vote Them Off The Planet.


RE: forgetaboutit
By Nexos on 1/30/2014 3:28:41 PM , Rating: 2
I think we could build robots capable of fully exploring Mars today.

Any manned mission to Mars would be either a first step towards eventual colonization (even in limited/temporary form, not talking about terraforming etc) or a matter of national (personal?) pride, like the moonrace was in the 60s. In case of the latter Mars makes particular sense, since it is the most famous of all planets other than Earth.

In terms of scientific research most demanding / dangerous / mundane tasks outside the habitat would probably be performed by some sort of robot anyway and the crew would act more as admins and maintenance, so its hard to see any real benefit to having them there.

Doing a manned mission to Mars "for the lolz" as is the case with Mars One seems like a colossal waste even if it succeeds, particularly since there are much more interesting places to visit in our solar system besides Mars, like Venus or the moons of Saturn.


Hmmm
By bah12 on 1/30/2014 12:02:10 PM , Rating: 2
Thought we already solved this by cutting their funding to the bones.




Please!
By faster on 1/31/2014 1:04:45 AM , Rating: 2
The USS Enterprise had artificial gravity and shielding against radiation! Isn't that the model we are chasing? Shields up! Arm photon torpedos. . .




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