November 05, 2013
Major Tom Aging Faster In Space
Ground control to Major Tom: You are getting older faster.
Bethesda, MD—As nations strive to put humans farther into space for longer periods of time, the real loser in this new space race could be the astronauts themselves. That's because experiments conducted on the International Space Station involving cells that line the inner surfaces of blood vessels (endothelial cells) show that microgravity accelerates cardiovascular disease and the biological aging of these cells.
Floating in a most peculiar way.
We did not evolve in space. So we are not adapted to it. We need biotechnology capable of reengineering our bodies before we'll be able to live healthily on the Moon or Mars.
Randall Parker, 2013 November 05 08:48 PM
Who wants to live on Mars or the Moon? Use material obtained from the asteroids to build gigantic space stations like the ones that that O'Neil guy with the funny haircut used to talk about. Very comfy, with parks and such, and gravity the same as Earth's.
I suspect that mars or even the moon will be a lot better for humans than zero G. Some gravity is probably a lot better than no gravity. Mars may be a better choice for a colony as it has twice the moon's gravitational pull and to avoid chronic werewolfism. (Notice how none of the Apollo landings occured during a full moon?)
I'd like to see what happens in Coriolis myself.
Strictly speaking, we don't know about the Moon, or Mars. We have two data points: One G, and zero G. We have no idea what biology does in the territory between. There could be a linear variation, or a threshold, or anything. We just don't know. For all we know, we'd be even healthier if we had MORE than one G of acceleration!
That's one of my big beefs with the International Space Station: The one, single solitary thing a space station could tell us, which we desperately need to know for planning the future of mankind in space, is how human biology reacts to fractional gravity. But the only way we're going to learn it is by building a rotating station with artifical 'gravity', so we can run the long term tests at different accelerations. We never should have built a zero G space station, it had nothing to tell us about this critically important question.
I'd like to know how they separated the effects of zero G from the effects of exposure to cosmic radiation. Because it looks like they didn't. Which is a moot point if the question is just 'is being on the ISS bad for you' ... but it's obviously highly relevant to the question of what to do about it.
I fully agree with your point about a zero G space station: we could separate how much of the effect is zero G versus how much is radiation. But what do we already know about radiation? A trip to Mars would expose astronauts to too much radiation. So wouldn't the same hold true for a space station?
Suppose the problem is radiation. We would need to live underground on Mars or the Moon.
Suppose the problem is radiation plus zero gravity. Mars gravity is weaker. The Moon's gravity is weaker still. So it is likely that even living underground would not be good enough.
If the problem is just zero gravity then, yes, a big and therefore expensive space station would address the problem. But so would staying on the planet Earth. Why move up into a massive and massively expensive space station?
If no gravity is really bad then it seems very likely to me that lower gravity would be bad but just to a lesser extent. The damage would just accumulate at a lower rate.
We would need extensive genetic re-engineering to live healthily in lower gravity environments.
The results were obtained from cultured cells and not by examining astronauts themsevles. Obviously the next step would be to see what is going on inside an astronaut on the ISS. Of course a lot of research has been done into the effects of weightlessness already and the general conclusion is that it's not good. A serious problem appears to be intercranial hypertension caused by fluid not draining away from the head as it does on earth. This can result in visual problems from the swelling of the optic nerve. The moon's low gravity should reduce this problem for people there, but I don't think it would eliminate it. But it would be interesting to see the frequency that children born and raised on the moon would develop cranial hypertension. There's a fair bit of plasticity in organisms so we may already have a significant ability to adapt to low gravity. Or we may not. (And it's a good thing there are ethics boards to stop people trying to find out by raising children upside down.)
Parker when will you get a little more cynical about
1. the media
2. the softer sciences, their staggering rate of unreproducible results, and the 'minimum publishable unit'.
These endothelial cells probably aged 3.2% faster, p less than 0.047, for all the lay press will tell you.
It's a job, la scienza. A job that is very romantic to a lot of people, thus very hard to get and keep. (You have a tenured chair, not a tenured grant. Less grants, less research and more teaching. No grants, no research.)
A lot, a whole lot of this stuff that gets published just isn't true. And then there's the consideration about martian gravity being quite a bit higher than zero, though it is indeed rather low.
Anyway, tons of people would trade away 20 years of life expectancy to live on Mars. Look at climbers. People who do repeatedly do the hardest Himalayas peaks and Arctic or Andes peaks are /quite/ likely to die, not rarely in a protractedly gruesome way. What risk was accepted by those involved in the moon effort, or anyone who volunteered for WWII? This is not a problem at all in practice.
But the novel 3001 by Arthur C. Clarke said that zero gravity almost stopped aging!
I go with Brett. No reason to believe this effect, even if reproducible, works at 1/3rd or 1/6th G. Moreover what ever effect it has on the aging process, if any, low gravity still puts less pressure on bones & heart. O'Neill colonies can be built for any G force and at 1/6th you might still live to 110 but be unable to return to earth. That beats the alternative.
Put artificial nanosized magnets into each cell I reason this would slow ageing.