NASASpaceFlight.com Forum
International Space Station (ISS) => ISS Section => Topic started by: mr. mark on 11/03/2011 02:36 pm
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Russian and ISS partners are considering putting astronauts on board ISS for up to 18 months simulating a Mars flight.
http://www.universetoday.com/90629/russia-considers-simulated-mars-mission-on-the-space-station/
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I don't get the point of this... ???
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From a health perspective it would present many challenges. Wonder what ideas they would come up with to prevent bone loss, blurred vision? If you think about it, the mission could result in possible research, benefiting bone loss patients here on Earth.
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I don't get the point of this... ???
Because we've never had someone in space long enough to go to Mars and back. So it makes sense to test that out when they are in Earth orbit and aren't in Martian orbit.
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These are all known and obvious, we need data from deep space outside the Van Allen Belts and for long duration periods for both human, electronic and mechanical systems…
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There's also a negative potential impact as well. If things don't go well from a health perspective, it would most likely mean a delay in HSF Mars plans, possibly a shift back to a lunar base where stays would be much shorter. Technology may have to catch up to Mars based goals.
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They'd need to put a centrifugal section on the ISS, IMHO. I've discussed this before (http://forum.nasaspaceflight.com/index.php?topic=27110.msg820720#msg820720).
Otherwise, this seems like a really sensible next step from the Mars500 experiment. They've done one test for psychological issues with the mission, and can now do another test to check for microgravity physiological issues as well. I wish them good luck with it.
A possible step after this would be to do the same sort of experiment on a station at EML-1, outside the van Allen belts, in order to test radiation protection technology.
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Related, in case you haven't seen it yet:
http://www.youtube.com/watch?v=_xUlhaFKjsE (http://www.youtube.com/watch?v=_xUlhaFKjsE)
Dr. Jesco von Puttkamer, Space Operations Mission Directorate, reviews 60 years of manned Mars mission analyses conducted at NASA and in Russia, starting from the historical first study, "The Mars Project," by Dr. Wernher von Braun and colleagues in 1948.
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These are all known and obvious
Well, many people thought they knew what was obvious about space travel in the 50's. Then they learned they didn't know and it wasn't obvious ;)
Maybe you should call the Mars500 people and let them know it's been solved?
we need data from deep space outside the Van Allen Belts and for long duration periods for both human, electronic and mechanical systems…
I'm not sure how closely you monitor the space program, but we don't have a human presence there. Baby steps.
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They'd need to put a centrifugal section on the ISS, IMHO. I've discussed this before (http://forum.nasaspaceflight.com/index.php?topic=27110.msg820720#msg820720).
Not viable on the ISS, too big, not enough power and disrupts the rest of the ISS.
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Perhaps a stupid question, but would partial gravity combined with carrying large weights in your pockets help?
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These are all known and obvious
Well, many people thought they knew what was obvious about space travel in the 50's. Then they learned they didn't know and it wasn't obvious ;)
Maybe you should call the Mars500 people and let them know it's been solved?
we need data from deep space outside the Van Allen Belts and for long duration periods for both human, electronic and mechanical systems…
You are still “obvious” Mr. Dale…
I'm not sure how closely you monitor the space program, but we don't have a human presence there. Baby steps.
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Not viable on the ISS, too big, not enough power and disrupts the rest of the ISS.
NASA's Technology Applications Assessment Team disagree with you (https://secure.wikimedia.org/wikipedia/en/wiki/Nautilus-X#ISS_centrifuge_demonstration).
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Not viable on the ISS, too big, not enough power and disrupts the rest of the ISS.
NASA's Technology Applications Assessment Team disagree with you (https://secure.wikimedia.org/wikipedia/en/wiki/Nautilus-X#ISS_centrifuge_demonstration).
Wrong. Nothing there disputes my claim.
That is a mechanical demonstrator and not a medical test. Also, it is still is disruptive.
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These are all known and obvious
Well, many people thought they knew what was obvious about space travel in the 50's. Then they learned they didn't know and it wasn't obvious ;)
Maybe you should call the Mars500 people and let them know it's been solved?
we need data from deep space outside the Van Allen Belts and for long duration periods for both human, electronic and mechanical systems…
You are still “obvious” Mr. Dale…
I'm not sure how closely you monitor the space program, but we don't have a human presence there. Baby steps.
Yes, and the baby steps start with zero g effects in LEO and not outside the Van Allen.
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We already know what zero g does to the human body.
Another study isn't needed.
Astronauts as guinea pigs rant ::)
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I don't get the point of this... ???
The longest any single person has lived in a microgravity environment is a little over 400 days. The empirical data set is miniscule and insufficient to extrapolate that we KNOW what will occur. Additional research in other areas relates, but honestly, we have absolutely no data past 400 days.
What actually happens? Is there a tipping point we should absolutely not go past? If so, how far or near is it? What mitigation factors are effective for that length of time? Which direction is our current, very limited dataset skewed?
We need to know this before we send someone 9 months out only to discover they won't be alive when they get home.
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We already know what zero g does to the human body.
Knowing the effects isn't the same as understanding them. Also, the experience over ~6 months is very limited, and predates the countermeasures currently used on ISS.
There is also opportunity to simulate other aspects of the mission.
Another study isn't needed.
An unjustified assertion.
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You are still “obvious” Mr. Dale…
I'm sure that made sense to you, but something got lost in translation ;)
It's not a complex process. We do NOT know everything that will happen to a human spending 500 days in space. This provides an opportunity to test that to the best of our existing abilities.
That should make sense to anyone...
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You are still “obvious” Mr. Dale…
I'm sure that made sense to you, but something got lost in translation ;)
It's not a complex process. We do NOT know everything that will happen to a human spending 500 days in space. This provides an opportunity to test that to the best of our existing abilities.
That should make sense to anyone...
Agreed, I'm just not sure if the ISS is the best place for such a demonstration. I would favor a free-flying BA-330.
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It may not be the best, but it does have a big advantage currently.
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Agreed, I'm just not sure if the ISS is the best place for such a demonstration. I would favor a free-flying BA-330.
Why so? ISS has far more capabilities (health monitoring equipment, etc.) than a BA-330.
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Agreed, I'm just not sure if the ISS is the best place for such a demonstration. I would favor a free-flying BA-330.
Why so? ISS has far more capabilities (health monitoring equipment, etc.) than a BA-330.
The biggest advantage I could see to using a BA-330 would be the ability to create an isolation mission similar to the Mars 500 simulation. Namely that the station could be stocked to be manned un-resupplied for the full duration. Additionally, communications delays could be built in for simulation realism.
However, if you're just wanting to get data on 2 guys for 18 months, then the ISS is fine. In fact, such a mission would be an excellent 'middle step' before trying to do an isolation mission.
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Additionally, communications delays could be built in for simulation realism.
There has been talk of doing communications delay exercises on ISS. See http://forum.nasaspaceflight.com/index.php?topic=24737.0
You wouldn't do it for the entire simulation, but useful intermediates are possible.
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Additionally, communications delays could be built in for simulation realism.
There has been talk of doing communications delay exercises on ISS. See http://forum.nasaspaceflight.com/index.php?topic=24737.0
You wouldn't do it for the entire simulation, but useful intermediates are possible.
My thought was that to do communications delays for a portion of the ISS crew would be disruptive to other ongoing projects.
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I can't believe that anybody on this board thinks we have a sufficient understanding of the long-term effects of microgravity to undertake a manned expedition to Mars.
I think it should be fairly obvious that we need at least one 500-day deep space habitation trial in a location with favorable orbital mechanics such as EML1. It's somewhat more debatable whether this trial should be preceded by a trial in earth orbit (e.g. at the ISS) where the microgravity effects can be evaluated independently of the more severe radiation environments of deep space.
One could argue that it's not much more difficult or risky to abort to earth return from EML1 than from LEO if necessary, so we might as well skip the LEO trial and go straight to the more realistic EML1 trial. But on the other hand, by the time we can begin the EML1 trial, we could have already completed the LEO trial at the ISS and possibly learned lessons which may inform the subsequent EML1 trial.
So I think we should do a 500-day habitation trial at the ISS. In fact, I think that this would help a lot of American taxpayers understand more clearly why the ISS is a worthwhile investment. If we can't figure out a non-disruptive way to conduct this trial on the ISS as it is configured today, then maybe we could roll it into the planned evaluation of the Bigelow module at the ISS.
Then we could proceed with another trial in EML1 or EML2 incorporating any lessons learned from the ISS trial. I'd be very surprised if we're anywhere close to ready to land humans on Mars by the time both trials are complete.
I don't think we'll ever land humans on Mars if we refuse to take a more incremental approach. I understand why many people argue that we'll reach this goal more quickly by taking a more aggressive tack, but I believe that this thinking only makes it more difficult to break out of the seemingly endless cycle of paper studies. If we proceed one step at a time, I think we're more likely to reach our final destination.
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These are all known and obvious, we need data from deep space outside the Van Allen Belts and for long duration periods for both human, electronic and mechanical systems…
It's not THAT different out there. And as far as electronic and mechanical systems outside Van Allen belts, every GSO satellite is beyond the Van Allen belts, and that's probably most all the commercial and military satellites ever launched. Plus every single planetary and lunar probe is beyond the Magnetosphere.
And we also have devices to simulate those levels of radiation on the surface.
Don't buy the paranoia about space radiation. It's an issue, but we absolutely have data about what the space environment is like beyond LEO and what we need to do about it.
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Agreed, I'm just not sure if the ISS is the best place for such a demonstration. I would favor a free-flying BA-330.
Why so? ISS has far more capabilities (health monitoring equipment, etc.) than a BA-330.
This is a great use of ISS, in my opinion. It's something NASA (and partners) can do quite soon to help us understand what's needed to get to Mars. An 18-21 month simulation at ISS would prove that we have a very important needed piece of the puzzle for a Mars mission. Taking the edge off of the radiation dosage (which is ~twice ISS dose rate) is nice, but I would argue has less uncertainty than ~20 months of operating in microgravity with no resupply from Earth.
A few of these simulatons at ISS (eventually with the whole exploration stack docked at ISS), combined with a trip to a NEO, would show we have basically all the stuff needed for a short-duration Mars orbit mission (plus a little extra strategically placed water shielding... imagine wearing a big, water-filled inflatable parka when outside of the sleeping quarters).
All that's needed for a surface mission would be a small lander (with a pre-landed ascent vehicle) to allow sorties.
Pre-landed base components would continue the incremental build-up of capabilities to a full permanent base.
The key is small, incremental steps like these ISS simulations. I applaud the simulation efforts, and will be excited to see them!
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Build it, send it out there… Test like you fly… Get out of LEO!
http://www.ukintpress-conferences.com/conf/aerona05/pres/spacetest/white.pdf
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We already know what zero g does to the human body.
Another study isn't needed.
Astronauts as guinea pigs rant ::)
An 18-21 month mission simulation on ISS would prove that we have the problem licked enough to consider sending astronauts to Mars for that long. Russians tried this before with one cosmonaut for 14 months (and it actually worked reasonably well; the cosmonaut insisted on walking a bit on his own after landing), but our boneloss mitigation techniques (and understanding of the process) have improved significantly since then and we also have far, FAR better drugs available to treat osteoporosis as well. It's time we put them to the test.
There will always be significant uncertainty in Mars mission planning until we've demonstrated an 18-21 month mission in LEO first. Gemini tested Apollo 11's 8 day mission duration with a test in LEO lasting 14 days. ISS (and maybe a NEA mission) is our Gemini.
Add a dedicated simulation section (with a separate module docked to an Orion, perhaps) for a better simulation while still being attached to the Station for safety (and power, etc) may be a good next step after this.
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These are all known and obvious, we need data from deep space outside the Van Allen Belts and for long duration periods for both human, electronic and mechanical systems…
How is something that's never been tested a known and obvious?
Plus I'd like to see a few more Americans on this list
http://en.wikipedia.org/wiki/List_of_spaceflight_records#Ten_longest_human_space_flights
Not viable on the ISS, too big, not enough power and disrupts the rest of the ISS.
NASA's Technology Applications Assessment Team disagree with you (https://secure.wikimedia.org/wikipedia/en/wiki/Nautilus-X#ISS_centrifuge_demonstration).
That is one small centrifuge.
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Build it, send it out there… Test like you fly… Get out of LEO!
As mentioned by countless posters already - that's not viable. I'm glad you have such enthusiasm for the space program, but for whatever reason you are just not grasping the reality of where it is today.
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We know what will happen if we send somebody to ISS for 400 days.
Bone density loss and muscle atrophy.
Putting humans through this torture just for the sake of it is simply not on in my eyes.
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Bone density loss and muscle atrophy.
Putting humans through this torture just for the sake of it is simply not on in my eyes.
In order to send men to Mars, we will need to overcome these problems, either by providing partial gravity sections, or with drugs and rigorous physical exercise regimens.
Before sending the mission, we need to do some experiments in a controlled environment to determine whether or not these problems have successfully been overcome.
You can only do these tests on humans, because they require subject cooperation.
Several other posters have already pointed out that our understanding of the affects of long-duration microgravity and our drugs etc. for treating it have improved greatly since the last time any long-duration experiments were carried out, so their results are no longer necessarily representative of what can now be achieved.
All in all, such a simulated Mars mission would not be "pointless", "astronauts as guinea pigs", "torture just for the sake of it", or any other misleading and insulting epithet that you wish to use. ::)
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But what's the point?
Without a centrifuge to control the gravity it doesn't mean much.
You need to spin the men up to Mars G after 180 days and put them back into zero G after a simulated surface stay.
If you just want to throw people in space for a long duration we already know EXACTLY what will happen.
Mir, Skylab and ISS have covered this for DECADES!!!!!!!!!
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Outside of an unlimited budget you test what you can with what you have. We have the ISS, we have it staffed, and the budget for these tests are not large enough to kill other more useful projects.
ISS is going to fly at least till 2020, if you have a problem with this plan, can you think of something better to use the current hardware to test that's not going to add significant cost?
We have a Congressionally mandated HLV and capsule, so everything else can starve till they are done. Better to use the crumbs left over to test this than to have ISS twittle it's thumbs till it falls into the Pacific.
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Some won’t like to hear this… It appears that the ISS is just looking for something to do and some reason to exist outside of international politics. General Bolden stated that the “ISS is our Moon”. Now the “ISS is our Mars”… You can simulate all you want… Restart NERVA and reduce the transit times. Test like you fly… Or you can always accept a Zubrin-like proposal if you are not so risk adverse.
Quotes:
CHRISTOPHER FERGUSON, SHUTTLE ATLANTIS COMMANDER: You know, Mars has been 20 years in the future for the last 30 years.
... We essentially have command of low earth orbit.
GENE CERNAN, APOLLO ASTRONAUT: Once you've been to the moon, staying home is not good enough. I'm an exploration guy. I want to go where man has never gone before.
http://transcripts.cnn.com/TRANSCRIPTS/1107/03/cp.01.html
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You can simulate all you want… Restart NERVA and reduce the transit times. Test like you fly… Or you can always accept a Zubrin-like proposal if you are not so risk adverse.
Why not do both? ::)
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If you just want to throw people in space for a long duration we already know EXACTLY what will happen.
Actually, we don't know EXACTLY what will happen. If you scroll through some of the posts in this very thread, you can see the advantages of this plan.
Some won’t like to hear this… It appears that the ISS is just looking for something to do and some reason to exist outside of international politics.
Well, of course. That's called "common sense." If you have an underutilized system, utilize it.
Restart NERVA and reduce the transit times. Test like you fly… Or you can always accept a Zubrin-like proposal if you are not so risk adverse.
NERVA, Zubrin, etc. are never referenced in the opening post. They aren't part of the proposal. If people would write less and read more they'd actually learn something instead of contributing to the noise.
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Mir, Skylab and ISS have covered this for DECADES!!!!!!!!!
No, it was found that the Russians didn't use proper protocols during MIR so their data is suspect. Skylab was less than 6 months total. So there is limited data.
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More info...
The next few years are expected to bring additional experiments aimed at testing the waters for Mars missions. NASA has been talking about setting up time delays in Earth-to-space communications, to reflect the minutes-long light-speed travel times between Mission Control and a spaceship heading for Mars. A 10-minute time delay is on the space station's tentative science agenda for next year. Several experts have suggested attaching prototype Mars modules to the station for future test runs.
Russian space officials are thinking about conducting a Mars500-style experiment aboard the space station sometime after 2014, the Itar-Tass news agency reported today. "We are interested in staging such an experiment in actual conditions of zero gravity," Vitaly Davydov, deputy chief of Russia's Federal Space Agency, told Itar-Tass. "It is too early to say when such an experiment could be made."
If the plan goes forward, at least two astronauts would spend at least 18 months in orbit. That timetable is much longer than the typical four- to five-month tour of duty — and would set a new record for time spent in space. The current endurance record is 437 days and 18 hours, set in 1995 by Soviet cosmonaut Valery Polyakov aboard the Mir space station. Polyakov was said to suffer some low moods during his record-setting stint in space, but there were no lasting physical impairments, and by all accounts he's still healthy at the age of 69.
"I was able to stand up and walk on Earth after being in zero gravity," he told an interviewer at the New Mexico Museum of Space History in 2007, "so it should be easy to stand up and walk on Mars."
http://cosmiclog.msnbc.msn.com/_news/2011/11/03/8620373-whats-next-for-a-make-believe-mars
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... We essentially have command of low earth orbit.
We have had essentially command of the earth for centuries, does not mean it will not make a good testing analog. ISS is there, we want to see how astronauts will be effected by the transit times and comm delays. Gemini never left ELO, yet was good practice in Lunar transit study as well as docking technology. We need to learn before we go, not throw money at fanciful technologies.
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Some won’t like to hear this… It appears that the ISS is just looking for something to do and some reason to exist outside of international politics.
I hear this all the time, and I honestly don't know where it comes from.
This proposal isn't a suggestion from the ISS program, rather it is the Mars 500 project scientists identifying that the ISS can be useful in their future experiments.
That is not "ISS looking for something to do", but is rather "ISS has an existing capability that can be utilised to scientists' benefit".
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But what's the point?
Without a centrifuge to control the gravity it doesn't mean much.
You need to spin the men up to Mars G after 180 days and put them back into zero G after a simulated surface stay.
If you just want to throw people in space for a long duration we already know EXACTLY what will happen.
Mir, Skylab and ISS have covered this for DECADES!!!!!!!!!
No, you are wrong. We do have tools at our disposal (besides a big centrifuge) to mitigate microgravity effects. Many tools, in fact. A short list of tools, all of which are less expensive, less massive, and easier to develop than a large centrifuge:
1) better exercise regiment (oddly, just increasing the tightness of the elastic bands holding astronauts to the treadmill has a quite marked effect)
2) longer exercise time (at least during transit)
3) a whole suite of powerful and effective anti-osteoporosis drugs (some being tested on ISS as we speak, actually... interestingly, we hadn't been using any of these drugs before)
4) elastic suits, like the cosmonauts wear (but maybe better)
5) small short-arm centrifuge (apparently has most of the benefits of a large centrifuge, but could fit in an existing ISS module)
6) bone-density increasing vibration
And we really haven't put all these tools to the test in LEO, yet, so obviously we don't know what their effect will be. Partly because the astronauts/cosmonauts are busy doing other tasks. And it's also important to know what the effect will be on crew productivity, etc.
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We know what will happen if we send somebody to ISS for 400 days.
Bone density loss and muscle atrophy.
The devil is in the details.
~snip~
5) small short-arm centrifuge (apparently has most of the benefits of a large centrifuge
What I've read is that there isn't really much useful data on the subject so I'm very curious where you got your info from.
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We know what will happen if we send somebody to ISS for 400 days.
Bone density loss and muscle atrophy.
The devil is in the details.
~snip~
5) small short-arm centrifuge (apparently has most of the benefits of a large centrifuge
What I've read is that there isn't really much useful data on the subject so I'm very curious where you got your info from.
I've seen some preliminary results from some small-arm centrifuge studies that show that a limited time (daily) in 1 gee or even hypergravity can mitigate most of the problems. I don't have a link handy, and it'd probably take a while. Ask me again sometime and I'll try to dig it up.
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Would it be possible to attach a booster and fly the ISS over to Mars?
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There's a good (and recent) FISO presentation on the subject and particularly small-arm centrifuges, Mars missions and the ISS (the mp3 is worth a listen): “Artificial Gravity, the ISS, and a Solution to Long-Duration Space Flight”
http://spirit.as.utexas.edu/~fiso/telecon/Young_7-20-11/
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Would it be possible to attach a booster and fly the ISS over to Mars?
Not shielded enough for interplanitary travel, and in a very wrong orbit to allow transfer to Mars injection.
It's a shame, but that is not really possible :(
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Would it be possible to attach a booster and fly the ISS over to Mars?
When you consider that a loss of this last Progress would have resulted in the ISS being closed down, I think the resupply route to Mars would have been too much to handle ;)
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Would it be possible to attach a booster and fly the ISS over to Mars?
When you consider that a loss of this last Progress would have resulted in the ISS being closed down, I think the resupply route to Mars would have been too much to handle ;)
You missed the point entirely. ISS would've needed to be unmanned because the Progress which had problems used the same rocket essentially as Soyuz, and Soyuz only has an on-orbit lifetime of about 200 days. ISS had plenty of supplies for quite a while.
But anyways, ISS isn't made for high acceleration... it would be unsafe to use a large chemical booster in that manner because it'd have too much thrust. A very low thrust booster of some sort, perhaps even an ion engine or something, would work.
But alas, ISS is not designed for that environment. If you had plenty of time and were designing another ISS with that capability in mind, it probably wouldn't be too hard to do it, but not with ISS as is. Structural issues are the biggest. Also, ISS is incredibly massive. It'd take multiple launches of even the biggest version of SLS to get ISS to Mars orbit.
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Some won’t like to hear this… It appears that the ISS is just looking for something to do and some reason to exist outside of international politics.
I hear this all the time, and I honestly don't know where it comes from.
This proposal isn't a suggestion from the ISS program, rather it is the Mars 500 project scientists identifying that the ISS can be useful in their future experiments.
That is not "ISS looking for something to do", but is rather "ISS has an existing capability that can be utilised to scientists' benefit".
Well Pete, you know the warm feelings I have toward the ISS and the great engineering achievement that it is. Perhaps we hear things like what Irene Klotz wrote for Discovery News, referring to it questionably is it a “Boon or Boondoggle” a couple of years back. Is ISS underutilized or over utilized? As long as it doesn’t drain any precious funding, let them have at it… ;)
Regards
Robert
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You missed the point entirely. ISS would've needed to be unmanned because the Progress which had problems used the same rocket essentially as Soyuz, and Soyuz only has an on-orbit lifetime of about 200 days. ISS had plenty of supplies for quite a while.
No, I think the point flew past you ;) The ISS needs to be resupplied (relatively) frequently. You can't do that in Mars orbit.
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Flying astronauts for four or five hundred days may generate useful medical data but not necessarily the most useful data.
I have read somewhere (possibly on this forum) that NASA docs are more interested in number of subjects in order to draw more statistically significant conclusions regarding a countermeasure. Since most adverse adaptations to zero G occur in the first few weeks to months, you may not need to observe a subject and his or her reaction to countermeasure for greater periods of time. That is the reason I have heard it said that NASA flight docs would rather see more 3 or 4 month missions rather than the current 5-6 month missions which are driven only by spacecraft capability and availability.
In other words:
4X number of astronauts flying 90 day sorties probably gives you more insight into efficacy of countermeasures than does X number of astronauts flying year long sorties or 1/2X number of astronauts flying two year long sorites.
The primary benefit to 300 or 600 day sorties is most likely psychological.
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When a crew goes to mars, they will most likely experience communication delays of several minutes. I do not know for sure, but during the MARS500 experiment they simulated a communication delay of about eight minutes during their stay on the martian surface.
Right now there is a communication delay of a about a tenth of a second between the Ground and the ISS.
I think the ISS partners want to experiment with communication delays, when they are talking about a simulated mars mission. I think there is less intrest for increesing the flight duration.
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In other words:
4X number of astronauts flying 90 day sorties probably gives you more insight into efficacy of countermeasures than does X number of astronauts flying year long sorties or 1/2X number of astronauts flying two year long sorites.
But again the Mars mission will be far longer than 90 days... So someone has to study it.
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The primary benefit to 300 or 600 day sorties is most likely psychological.
It may well be true that shorter stays are better for evaluating countermeasures, but it seems doubtful we can actually have much confidence on the effects of longer flights. Only 6 people have flown > 300 days in a stretch, all in the Mir era.
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Since most adverse adaptations to zero G occur in the first few weeks to months, you may not need to observe a subject and his or her reaction to countermeasure for greater periods of time. That is the reason I have heard it said that NASA flight docs would rather see more 3 or 4 month missions rather than the current 5-6 month missions which are driven only by spacecraft capability and availability.
Some reach a nominal zero-g steady state in approximately 6 weeks (with current countermeasures); see chart below from:Artificial Gravity, the ISS, and a Solution to Long-Duration Space Flight (http://spirit.as.utexas.edu/~fiso/telecon/Young_7-20-11/), Jul 2011, Laurence Young MIT FISO presentation.
For those, more subjects over shorter duration may be more beneficial to our understanding and development of better countermeasures. However, note the two significant exceptions: bone and calcium; and radiation. Those are currently the primary concerns for long duration spaceflight.
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Your point regarding bone loss is well taken; however, from a doc's standpoint it is going to be more helpful to me see to what degree a countermeasure, say a bisphosphonate for example, is going to start to do in three months. If there is no difference compared to a control I don't need to go 12 mos on an astronaut. What I do need is adequate numbers of subjects so that I can develop an understanding of the pharmacokinetics and pharmacodynamics of said interventions. As someone mentioned ISS is the only ship we have to fly for the foreseeable future. It is not like there are enough positions to fly a lot of people for 12-24 months.
Also, you make the very valid point regarding radiation. There are very real disadvantages to running all your astronauts out to their maximum exposure on their first and only flight. Recall that the original flight engineer on Expedition 6 was pulled off due to cumulative radiation exposure and that was just due to several shuttle flights. He had never flown a long duration flight. Also Sunni Williams was brought back on an earlier STS than planned due to concerns about her level of exposure.
Also, keep in mind that the things everyone says they are interested in are not necessarily what they are really interested in. You mention bone mineralization and radiation which are good examples. These are excellent surrogates to study and should be studied. But remember what you are really interested in are 1) increased fractures; 2) malignancy; 3) unanticipated consequences; 4) all cause mortality.
Finally, for what it's worth, having practiced medicine for over a decade now I would like to think I have a pretty good idea of what this human body I can tolerate. Having witnessed first hand war, trauma, horrific diseases, and sometimes equally horrific treatments, I don't have any doubt that an astronaut can fly in zero G for six months, manually land on Mars, live there for 18 months then fly back home in zero G for another six months and then land on Earth. Human beings cope with physical problems greater than that all of the time.
The bigger question is what will the astronaut's health be like on return? What will their recovery be like? What is the long term morbidity and mortality attributable to that kind of flight?
Since we have ISS we should be flying folks in the most efficient way to learn as much as we can before we leave for Mars but that does not mean we have to learn EVERYTHING before we head out.
Earlier Jim dismissed the centrifuge on ISS. He is absolutely right. It would have been totally inadequate for these types of questions. Better way to do that is to put two Bigelows on a tether and spin them. Could be done in LEO but since we have SLS why not do it at EML, or enroute to Phobos, or an Athena type mission. Could be done with all of the above and needs to be because we have no clue how much gravity you need .1G, .16G, .38G, or 1 G. This would take multiple missions with multiple astronauts.
Bottom Line: Let's use ISS as best we can for the next decade but realize we still will not know everything we would like to know about human countermeasures for spaceflight. Let's not keep using the same tired human factors excuse as a reason why we can't go to Mars. Let's learn about human factors on the way to Mars.
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More info...
The next few years are expected to bring additional experiments aimed at testing the waters for Mars missions. NASA has been talking about setting up time delays in Earth-to-space communications, to reflect the minutes-long light-speed travel times between Mission Control and a spaceship heading for Mars. A 10-minute time delay is on the space station's tentative science agenda for next year. Several experts have suggested attaching prototype Mars modules to the station for future test runs.
Russian space officials are thinking about conducting a Mars500-style experiment aboard the space station sometime after 2014, the Itar-Tass news agency reported today. "We are interested in staging such an experiment in actual conditions of zero gravity," Vitaly Davydov, deputy chief of Russia's Federal Space Agency, told Itar-Tass. "It is too early to say when such an experiment could be made."
If the plan goes forward, at least two astronauts would spend at least 18 months in orbit. That timetable is much longer than the typical four- to five-month tour of duty — and would set a new record for time spent in space. The current endurance record is 437 days and 18 hours, set in 1995 by Soviet cosmonaut Valery Polyakov aboard the Mir space station. Polyakov was said to suffer some low moods during his record-setting stint in space, but there were no lasting physical impairments, and by all accounts he's still healthy at the age of 69.
"I was able to stand up and walk on Earth after being in zero gravity," he told an interviewer at the New Mexico Museum of Space History in 2007, "so it should be easy to stand up and walk on Mars."
http://cosmiclog.msnbc.msn.com/_news/2011/11/03/8620373-whats-next-for-a-make-believe-mars
A more accurate simulation would be to have them stay one normal ISS duration then return to Earth for a few weeks then have them stay on ISS again for another 5 to 8 months.
This should simulate a sprint class Mars mission.
Though it would not break any records.
For maximum safety the LV for the second launch and the return vehicle for the second ISS stay should be chosen for the lowest G.
Orion on SLS should have the lowest G on the way up and Dream Chaser the lowest on the way down.
Though if they decode to fly an entire Mars duration all at once DC,CST-100 or Orion in that order would probably be the best vehicles for return.
Earlier Jim dismissed the centrifuge on ISS. He is absolutely right. It would have been totally inadequate for these types of questions. Better way to do that is to put two Bigelows on a tether and spin them. Could be done in LEO but since we have SLS why not do it at EML, or enroute to Phobos, or an Athena type mission. Could be done with all of the above and needs to be because we have no clue how much gravity you need .1G, .16G, .38G, or 1 G. This would take multiple missions with multiple astronauts.
A centrifuge on ISS would be nice but you can't easily add one big enough for people to live in.
Two BA330s or Sundancers might actually be cheaper after considering the political red tape in adding something like that to ISS.
They'd would be more flexible too and it would be a centrifuge big enough to live inside of vs lay down in.
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You don't need to live in the centrifuge to get its beneficial effects. Exercising in hypergravity works.
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You don't need to live in the centrifuge to get its beneficial effects. Exercising in hypergravity works.
It just makes things easier for the crew.
Though rotation rate is an issue a lot of people got sick if they spent more then a few minutes in a short arm hyper gravity centrifuge.
For larger centrifuges like those on Nautilus-X I wonder if they could invent games that can be played inside the centrifuge to remove the drudgery of the mission and make the exercise routine fun.
The psychological issues are just as important as the physiological issues.
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I too am very much a fan of the ISS - surface analogue - ISS type mission. That would be a great way to use ISS and you could start in just a couple of years. The extra costs would be negligible. It would also give you a good way to evaluate mission architectures: conjunction vs opposition missions with short stay times. You would learn a lot about crew health but also science operations, training plans, etc.
Most significantly, it would make the American taxpayer feel like we are making genuine progress and make the politicians feel that the manned space program is make a tangible return.
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I'm now coming around to this idea.
If astros want to volunteer for the long stay they're quite welcome.
I'm sure there's heaps of them that would jump at the opportunity to live up on ISS for more than the usual 6 month period.
We don't need a centrifuge to go to Mars anyway.
Perhaps testing the extreme limits of zero G living is worthwhile (500+ days).
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Earlier Jim dismissed the centrifuge on ISS. He is absolutely right. It would have been totally inadequate for these types of questions. Better way to do that is to put two Bigelows on a tether and spin them. Could be done in LEO but since we have SLS why not do it at EML, or enroute to Phobos, or an Athena type mission. Could be done with all of the above and needs to be because we have no clue how much gravity you need .1G, .16G, .38G, or 1 G. This would take multiple missions with multiple astronauts.
Thanks for your post, and very much appreciate your perspective as a practitioner.
In fairness, Jim objected to one form of centrifuge, or more precisely one form of AG experimentation on ISS; not sure he objects to all (and I'll leave it to him to clarify), but the gnomes of ESA and NASA appear to believe a short-arm centrifuge could be placed on the ISS without disruption.
If short-arm centrifuges are a promising solution (which they appear to be), what is the objection to proceeding down that path? It certainly appears to be a cheaper--and something that might be done on the ISS or similar sooner rather than later--alternative rather than constructing a large rotating torus or tethered arrangement.
Granted, that doesn't necessarily answer the question of what happens for extended periods between 0-1g (e.g., an extended lunar or Mars surface stay), but certainly if we can find a 0-g solution, that would hold promise for 1/6-1/3g environments?
It just makes things easier for the crew.
Though rotation rate is an issue a lot of people got sick if they spent more then a few minutes in a short arm hyper gravity centrifuge.
It doesn't necessarily make things easier for the crew if they have to transition (and re-adapt) between environments. Decreasing adaptation time and deleterious effects is the subject of much concern, altho admittedly we don't have much experience or effective facilities to make a determination.
Rotation rate and adaptation is an issue in some circumstances and for some people. However, a significant chunk of short-arm centrifuge research is determining how people adapt, how to improve that adaptation (both to and from), and how to decrease adaptation time. While the results are limited, they have been promising.