The Human body on Mars vs Earth

martienne · 2015-10-11 16:20:44

Once a person got used to the gravity of Mars, alternatively if they were born on Mars and grew up there: Would they be able to adapt to life on Earth? Would they look different? What would it take for them to re-adjust to life on Earth?

Tom Kalbfus · 2015-10-11 16:23:59

I don't really know, no one has ever been born on Mars. I don't know what the human body would do if it grows in a low gravity setting, only an experiment can find out.

Void · 2015-10-11 20:21:18

Tom is right of course, but there are now some clues, which makes me happy

I recall that chickens have been raised in a centrifuge under 3 gees? Their legs were very strongly muscled. Too bad we don't have a super Earth in our solar system. This suggests that animals and perhaps humans could adapt to it. They might want to change to knuckle walking however. Less chances of falling and breaking bones I would think. But not a problem, no super Earth.

So, depending on how you body was able to put on muscle (Your age, and other factors), coming to Earth, I would presume that therapy might get you walking on Earth. The kind of therapy that would be applied to a person who was bed ridden, I suppose.

Now I am beginning to think that NASA and it's international friends are doing fantastic work on the ISS.

http://www.tested.com/science/space/456 … oss-space/

NASA has been studying the effects of microgravity on the human body for almost as long as it has existed. On the International Space Station, their current research has focused on nutrition and how the human body is affected by different nutrients while in space. This particular research was difficult to do until 2006, because it requires sampling the blood and urine of astronauts (the samples need to be collected in space, stored and frozen, and returned to earth for analysis).

One of the biggest discovery to come out of this area of study is how salt affects our bones. Astronauts experience accelerated osteoporosis while they’re floating around in microgravity. As a result, NASA has developed methods to assist them with combating the degradation of their bones and a return to normalcy once they hit solid ground. What researchers have discovered is that accelerated bone loss is tied directly into the strange fact that in space astronauts retain salt in their body--but not water.

Looking more closely at salinity in astronaut’s blood and urine, researchers were able to determine that sodium is retained (most likely in the skin) and changes the body’s acid balance, which in turn changes bone metabolism. In other words: the more salt in your body the more quickly your bones will deteriorate. Researchers believe this discovery will have big implications in the fight to treat the world’s osteoporosis problems (not to mention necessary adjustments to the dietary habits of space-goers).

I am guilty of getting mad about NASA taking endless urine samples, instead of building a centrifuge or going somewhere, but how about that, I am a brat. They done good, real good!

To try to get rid of the salt in the skin, perhaps a Sauna can be though about/tried? Might be a good way to take a bath in space. A short rinse with a cool shower after? You probably need less soap using a sauna, might get the dirt and stink off better. Maybe that will turn out to be good for old people as well. I hope so.

http://www.news-medical.net/news/201510 … -loss.aspx

I won't quote this, they have their own ideas about what the problem might be, and I don't want to coat myself with too much intrusive "Stupid", but I noticed in their analysis they mention calcium as a trigger in the cell. I wonder if bone loss and muscle loss are related due to calcium, and as in the above bone theory, the retention of salt, and so the change of PH? of the human body.

Maybe regulating salt might help with the muscle loss.

What goes on in microgravity is not what you asked, but your person moving from Mars to Earth, might have to deal with it, so perhaps it can be considered.

Also microgravity to 3 gees in a centrifuge apparently can bound historical experiences of working with animals and humans.

So Mars at .38 is in between those limits.

There are some other problems with Microgravity which I hope will not appear on Mars. Pooling of blood in the upper body, and apparently damage to the Eyes, possibly from that?

I am hoping that the effect is not linear. I hope that with some minimal gravitation the body is able to regulate fluid volumes in the body. Obviously it cannot in Microgravity, or that is what we are told.

I might suppose that if it is a problem in gravity fields that humans might occupy for long periods, some kind of shunting of blood flow might help, but then if you returned to Earth, you would need that reversed. I hope it is not a requirement.

I hope that some relatively small amount of centrifugal force, along with space medicine will allow habitation of Microgravity for long periods. A very weak centrifuge would be handy anyway since objects would not float around all the time. It would be much more "Normal to a human. 1/10 gee or less? (I could hope) I also hope that Mars will be within the bodies ability to adjust, so that minimal space medicine will be required.

However, as Tom said, we don't know really, but per the above we are being given some clues.

Last edited by Void (2015-10-11 20:44:00)

SpaceNut · 2015-10-11 21:22:57

The ISS twin comparison may lead to the exact nature of gravity and the changes that go on in the human body.

martienne · 2015-10-12 06:45:32

There must be some desalination treatment (pills) that can be routinely administered to humans, if it should turn out that there is an unhealthy buildup of salt in the body of individuals who live in lower gravity environments..
There is probably already some illness or another that leads to an unhealthy build-up of salts in the body.
A physician would no doubt know...

Perhaps nobody has been exposed long enough to spae conditions for research to look into this.
The person who spent the longest in space was a Russian, at the ISS.
I assume he's been thoroughly studied. Would be interesting to read up on what they found.

(It's true that saunas drive out a bit of salt (and other junk) from the body, but possibly not in sufficient quantities to be useful (?) It works for minor stuff though. I once managed to clear my body of any trace of something I'd smoked the day before, by doing an extremely long run, drinking some vinegar (!!!) and then spending 2 hours in the sauna. Traditional boarding school cure.
A bit hard to imagine a sauna on Mars - couldn't exactly be a traditional one...)

In sci-fi books, it seems to be common to assume that the body takes on different characteristics, for people who grow up in lower gravity. I.e. Mars trilogy and Expanse series.
But are they guessing or basing it on scientifical data + projections?

Another thing to consider is: These people will never be exposed to sunlight on their skin. That is needed to produce Vitamin D. Without it, people get sick and depressed. It's already a problem for black people in Northern climates, like Scandinavia. Their skin is doesn't absorb the existing sunlight well enough, and they have to take extra D vitamin.

A person on Mars would either have to simulate sunlight on the skin with a sun-lamp assuming that can "trick" the body, or take quite large doses of Vitamin D.

SpaceNut wrote:

The ISS twin comparison may lead to the exact nature of gravity and the changes that go on in the human body.

Where can we read about this?

Last edited by martienne (2015-10-12 06:46:21)

Void · 2015-10-12 10:51:39

Interesting you would mention Vitamin D.

http://www.ncbi.nlm.nih.gov/pubmed/16077253

Also I recently read an article which indicated that there could be a strong reason to think that such supplements along with resistance training might really be effective in controlling bone loss in space flight. Very encouraging.

SpaceNut · 2015-10-12 11:38:07

NASA's Twin Astronauts Volunteer as Guinea Pigs for Space Science

Nasa twins to embark on year-long space experiment Twin Nasa astronauts Mark and Scott Kelly are to put Einstein to the test in a pioneering study that could pave the way for humankind reaching Mars

The Kelly Twin project will examine how individuals with the same genetic profiles respond to radically different environments. Researchers already know that life in orbit can have profound changes on astronauts. They experience the loss of bone and muscle, as well as vision problems and changes affecting motion and balance – and all these will be examined in detail.
In addition, researchers will compare the men’s immune systems, reaction times and the performance of their hearts. Blood and urine samples will be taken regularly and, in Scott’s case, flown to Earth. Analyses will then tell scientists if Scott’s DNA is changing in space. MRI images will also be taken of Scott, while the trillions of bacteria – the microbiota – that live inside the astronauts’ digestive tracts will be sampled and analysed. And all these studies will be mirrored in tests carried out on Mark on Earth

NASA to Conduct Unprecedented Twin Experiment

In March of 2015, NASA astronaut Scott Kelly will join cosmonaut Mikhail Kornienko on a one-year mission to the International Space Station. Their lengthy stay aims to explore the effects of long-term space flight on the human body.
"We already know that the human immune system changes in space. It's not as strong as it is on the ground," explains Kundrot. "In one of the experiments, Mark and Scott will be given identical flu vaccines, and we will study how their immune systems react."
Another experiment will look at telomeres--little molecular "caps" on the ends of human DNA. Here on Earth, the loss of telomeres has been linked to aging. In space, telomere loss could be accelerated by the action of cosmic rays. Comparing the twins' telomeres could tell researchers if space radiation is prematurely aging space travelers.
Meanwhile in the gut, says Kundrot, "there is a whole microbiome essential to human digestion. One of the experiments will study what space travel does to [inner bacteria] which, by the way, outnumber human cells by 10-to-1."

SpaceNut · 2015-10-14 20:58:14

Risk is a part of space travel but what are the ethical questions.... http://spirit.as.utexas.edu/~fiso/telec … -15-15.pdf

GW Johnson · 2015-10-15 09:05:38

Microgravity diseases go far beyond just bone and muscle loss and weakening of the heart and circulatory system, a broad-brush statement, but still true. There seem to be degradations of vision and the immune system. Who yet knows what else?

All of these that we know so far seem to be retardable, but not stoppable. That's another broad-brush statement, but it also seems to be true, as best we know. Currently, a little over a year in space makes a 4 gee return ride medically challenging, with many months of recovery after the person comes home.

And we know nothing "for sure" about any therapeutic effects of fractional gee, precisely because we have never experimented with partial gee by centrifuge in orbit.

Mars is 2+ years away (round trip) at zero gee in transits or rather low gee while on the surface, in most mission scenarios, some of which push a 3 year round trip. Most free return scenarios involve something like a 15 gee ride at faster-than-escape entry speeds.

I don't know about y'all, but when I look at that time-to-disease vs tolerance-for-stresses-upon-return disparity, I see no ethical solution space that does not include artificial gravity. None at all.

We know enough from the bed rest studies to know we need not sleep or recreate at full gee, but we ought to serve our work shift at full gee. Based on what seems tolerable to the "average Joe", that's a 56 m radius at 4 rpm. The trick is doing this radius structure out of things you have to take with you anyway, like propellant tanks and life support supplies, not added inert weights for trusses and cables and other Rube Goldberg stuff.

It is not hard to design practical spacecraft to this approach (although some still claim it is too hard). But it does require designing things that are fundamentally different from what has become traditional. It simply won't look like a Skylab or an ISS. It can't. But that does not mean we cannot build it, and by the same on-orbit docking assembly methods that we have used.

And that means you send these things to Mars from Earth orbit, not direct from the Earth's surface. Not even SLS could launch such things assembled. But you can assemble them on-orbit from things launchable with the commercial rockets we already have, which saves you a bundle on launch costs. Somewhere between a factor of 3 and a factor of 30 cheaper, depending upon whose lies about the cost numbers you choose to believe.

In a well-run program not developing new technologies, launch costs ought to be in the neighborhood of 20% of your total program cost. But if you develop new technologies, you will never fly anything in your program other than limited experimental demonstrators.

As for radiation, ethics requires shielding against solar particle events. That's 20 cm of water, wastewater, or wet foods around your designated shelter, in which you pass a few hours. The shielding won't help much with cosmic rays, nothing will. I'd recommend a Mars crew not make two deep space trips.

While at Mars, whether in orbit or on the surface, the planet adjacent to you blocks half the cosmic radiation. On the surface, there is also some shielding effect to be had from the atmosphere, thin as it is. Radiation is no excuse not to go.

Neither is microgravity. We already know what we have to do. Spin the damned thing. End-over-end makes sense for relatively-small vehicles.

The only truly limiting thing is a practical lander. It would be awfully nice if it were single stage and reusable (refuelled for multiple trips), and big enough to serve as at least part of a surface habitat. Such things are technologically feasible, but exceed the size of launch shrouds, even the projected SLS shroud. That means orbital assembly, but not all by docking. And that's the enabling technology where we still need some work before we go.

As difficult as it is to get people to Mars and back at this time, why go if you can't land? You may only get to make the trip once in this century, politics of money being what it is all around this planet.

GW

Last edited by GW Johnson (2015-10-15 09:26:48)

SpaceNut · 2015-10-15 18:59:42

Drug Could Repair Microgravity Health Damage

Microgravity is hard on your body. Muscles and bones weaken, pressure in your eyes increases, your motor movements change. It takes months of rehabilitation for an astronaut on the International Space Station to readjust to everyday life on Earth. Could drugs shorten this process?
Astronauts are already taking drugs these days to counteract bone loss, according to the research team. In addition to Vitamin D, calcium and lots of exercise (roughly two hours a day including setup time), they are encouraged to take bisphosphonate, a therapeutic agent that has been used to treat osteoporosis patients.
According to the research team, changes in cell shape can change different gene sequences that activate biochemical pathways — altering cell functions such as differentiation as cells divide. But there could be drugs created to counteract these effects, if they are found to be detrimental in the first place.
According to a NASA press release, more research is required to confirm that microgravity does indeed cause changes in cell cytoskeletons and their “gene expressions”.

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#1 2015-10-11 16:20:44

The Human body on Mars vs Earth

#2 2015-10-11 16:23:59

Re: The Human body on Mars vs Earth

#3 2015-10-11 20:21:18

Re: The Human body on Mars vs Earth

#4 2015-10-11 21:22:57

Re: The Human body on Mars vs Earth

#5 2015-10-12 06:45:32

Re: The Human body on Mars vs Earth

#6 2015-10-12 10:51:39

Re: The Human body on Mars vs Earth

#7 2015-10-12 11:38:07

Re: The Human body on Mars vs Earth

#8 2015-10-14 20:58:14

Re: The Human body on Mars vs Earth

#9 2015-10-15 09:05:38

Re: The Human body on Mars vs Earth

#10 2015-10-15 18:59:42

Re: The Human body on Mars vs Earth

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