Artificial Gravity on Mars?

[Airbrush]

Is it possible to build a shelter for people on Mars that rotates in such a way to create one G gravity on the surface of Mars? I was thinking of the slowly rotating "bicyle-wheel" space station that can create one G gravity anywhere in outer space. If that concept was slightly modified to rotate at an angle, the humans inside the Mars, or Moon, station would experience one G gravity. I was thinking of a cone shaped structure. The crew compartments would be at an angle of about 20 degrees from horizontal.

 

Except for that, I think it would be very bad for people to spend such a long time in one nineth G gravity that exists on Mars. Human missions to Mars would take years for a round trip.

 

Or the crew could spend most of their time in orbit around Mars in artificial gravity, and then only visit the planet for a few days or weeks at a time, before they return to normal one G gravity, to recover, in orbit around Mars.

[Pangloss]

Interesting idea; seems sound enough, if expensive to build.

 

Bear in mind that while we now have significant experience in microgravity ("zero-G") environments, we have zero long-term experience in low-gravity environments. We simply don't know at what gravity point the ill effects of microgravity are no longer found, nor have we any way to find out.

 

If memory serves, that was part of the purpose of the proposed return to the Moon, which has been scrapped (along with Mars, for that matter, rendering the point somewhat moot at the moment).

[Klaynos]

In what direction would it be rotating, around and around like a train or more like a Ferris wheel?

[Pangloss]

I think he's saying more like a train, but with a tilted track so that real gravity adds to the cumulative total instead of just disorienting the rider by pulling them in two different directions. Like a NASCAR driver at the apex of a turn.

 

(One of my favorite jokes: "NASCAR is easy, just push the pedal down as far as it will go, and for god's sake keep turning left!")

[Airbrush]

Thanks for your insights Panglos. I like the race-track analogy. I was thinking like a Merri-go-round with the crew quarters at a tilt towards the center. The crew would not be conscious of the rotation. They would only feel normal, steady, 1 g.

 

Over years in zero gravity will probably, eventually bring bad physical effects. So space travelers, for their health and longevity, should stay in an artificial 1 g gravity on one-way, multi-generational space missions, or even on several-year long missions to Mars, the asteroids, or even Jupiter's moons.

[D H]

A couple of corrections. Gravity on Mars is 0.38 Earth gravity, not 1/9. Second, it takes 6 to 9 months to get to Mars, not years.

 

Finally, Obama has taken the Moon and Mars out of the picture. He has moved both back to the realm of science fiction.

[Airbrush]

Thanks for the corrections DH. I just heard Mars had 1/9 the mass of Earth and jumped to the wild conclusion that meant Mars gravity was 1/9 of Earth.

 

As for how long a manned mission to Mars would take, you think from launch until returning to Earth would normally take less than one year? If so maybe 1/3 g is not too bad for human physiology, but a long-term base on the Moon might employ artificial gravity merri-go-round crew quarters for 1 g over a period of years.

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...Obama has taken the Moon and Mars out of the picture. He has moved both back to the realm of science fiction.

 

Yes, but that will stimulate robotics for space missions. Things like Kepler and Mars rovers can learn great stuff for us without the encombrance of humans on board, with the additional problem of returning them safely to Earth.

Edited April 26, 2010 by Airbrush
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[D H]

Yes, but that will stimulate robotics for space missions. Things like Kepler and Mars rovers can learn great stuff for us without the encombrance of humans on board, with the additional problem of returning them safely to Earth.

Will it? I doubt it.

 

The definition of insanity is doing the same thing over and over again and expecting different results. This experiment has been tried at least three times before. Only an insane person would expect different results. At the end of the Apollo program, both the US and Russia drastically cut funding for human spaceflight. Some scientists in the US had thought the Apollo program was an utter waste, and well, at least now some of that money would flow their way. That didn't happen. Instead, funding for unmanned space flight fell in the post-Apollo days. Funding for unmanned space flight similarly fell in the old Soviet Union. In the 1960s space scientists in Great Britain convinced Parliament to ban government funding of any human spaceflight activities. There are now very few space scientists left in Great Britain to celebrate that victory. Great Britain is in the process of lifting than ban.

 

Without the motivation that humans will soon follow, why bother? Unmanned space flight only looks cheap when compared to human space flight. Unmanned space flight is danged expensive when compared to other government funded science. The scientific return on investment from sending a billion dollar unmanned probe to Mars is tiny compared to the ROI from funding a bunch of cheap (very cheap) grad students who are doing ground-based research.

[michel123456]

(...) The scientific return on investment from sending a billion dollar unmanned probe to Mars is tiny compared to the ROI from funding a bunch of cheap (very cheap) grad students who are doing ground-based research.

 

I guess scientific return is only one of the elements. Sending man in space was intented to have military return, economic and politic. The economic one has been canceled when the Moon happened to be made of material similar with the Earth. The military happened to become restricted to a zone near the Earth, no star wars for the moment. The politic somehow vanished with the 2 precedents. The scientific alone is not enough to procede. Columbus didn't discover America in a scientific purpose.

[D H]

Michel, please re-read what I wrote. You somehow completely misread it.

 

Additionally, there had better be no military value in sending people into space. There is a specific international treaty against this.

[michel123456]

So it must be.

I re-read your post. You english is too elaborated for me.

[insane_alien]

D H, there are a few thing that can't be done by some cheap ground based gradstudents simply because of the fact that there's too much gravity around and could only be done in a space environment. until we can recreate that niche here on earth, space based experiments will have value.

 

and anyway, at some point we're going to have to leave this rock and relocate to another rock or two. the earlier this investment gets done the better chance we have of surviving in the long-long term.

[D H]

So it must be.

I re-read your post. You english is too elaborated for me.

Michel, I was very explicitly talking about unmanned space exploration; your response was in terms of human space flight.

 

D H, there are a few thing that can't be done by some cheap ground based gradstudents simply because of the fact that there's too much gravity around and could only be done in a space environment. until we can recreate that niche here on earth, space based experiments will have value.

Some value, yes. The question is how much? Earth observing satellites have a lot of value. Microgravity experiments, less so. Interplanetary missions, what's the rush if humans are not going to follow anytime soon? Take away that huge motivating factor and all that is left is scientific return on investment and some soft diplomacy returns ("my dog is bigger than your dog" writ large).

[insane_alien]

well, you could send up a robotic mining operation to strip a couple of asteroids. exploration, just seeing what's out there, humans don't need to be the probe to find cool stuff.

[D H]

Why do you think the results of getting rid of / drastically curtailing human spaceflight would be any different this time around compared to previous attempts to do the same?

 

The definition of insanity is doing the same thing over and over again and expecting different results.

[michel123456]

Ok I got it now (better late than never).

 

In order to get conversation back on track, or how to make artificial gravitation on Mars, I can only remark that our techniques are archaics. The only way we have to imitate gravitation is through acceleration. We have no electronic "gravitor" that can produce a gravitational field, or an anti-gravitational field.

[insane_alien]

We have no electronic "gravitor" that can produce a gravitational field, or an anti-gravitational field.

 

probably because all evidence so far says thats impossible. maybe if we get some form of unfied field theory there MAY be a way to do it but its miles away technologically speaking.

[Tnad]

It's good to stay optimistic about the future of man in space.But about the artificial gravity, it does not only depend on physics.The adaptation of the crew matters.For that reason we can't be sure of its success unless one has lived in.

And if you were planning for a big crew (in case it works), the construction may be much espensive than it is worth.

[Mr Skeptic]

The only way we have to imitate gravitation is through acceleration.

 

I believe that was the basis of General Relativity, that gravity and acceleration are indistinguishable.

 

We have no electronic "gravitor" that can produce a gravitational field, or an anti-gravitational field.

 

This would probably violate the law of conservation of energy.

 

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I wonder, if we had a large population living in artificial gravity created by rotation, would it be possible for some of the spacemen to leach energy from the rotation? Eg if it were two counter-rotating disks, maybe leech energy and store the rotational angular momentum in a flywheel, then carry the flywheel to the other side and repeat?

[Sisyphus]

I wonder, if we had a large population living in artificial gravity created by rotation, would it be possible for some of the spacemen to leach energy from the rotation? Eg if it were two counter-rotating disks, maybe leech energy and store the rotational angular momentum in a flywheel, then carry the flywheel to the other side and repeat?

 

If you leach angular momentum from a disk, it will slow down. You'd just have to use more energy than you leached to get it back up to speed again. Also, I'm not sure counter-rotating disks would be a good idea, since traveling between them would also screw with the momentum of each.

[VedekPako]

Why do we need to increase the gravity on Mars? Why not genetically alter man so that he can function perfectly on a terra-formed Mars?

 

To genetically alter a man so he can survive on Mars presently, will require the use of lots of cybernetics; it would be human only in mind and in form.

 

Additionally, there had better be no military value in sending people into space. There is a specific international treaty against this.

 

There's always going to be military value in anything man touches.

 

And treaties are only good as the paper they are written on.

[michel123456]

Good idea. But who will agree on the project of transforming the human body?

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There's always going to be military value in anything man touches.

 

Good observation. That makes me wonder about LHC.

[Airbrush]

Why do we need to increase the gravity on Mars? Why not genetically alter man so that he can function perfectly on a terra-formed Mars?

 

To genetically alter a man so he can survive on Mars presently, will require the use of lots of cybernetics; it would be human only in mind and in form.

 

I still haven't heard anyone say my centrifuge idea would not work to attain one g gravity on the surface of the Moon or Mars. Underground dwelling on Moon or Mars is the way to go, to shield the people from radiation. They enter down a central tunnel and then turn towards the "Merri-go-round" that brings the low gravity up to one G.

 

Genetically altering humans is way more complicated. Or, if my centrifuge won't work, you can have perfect one G gravity in orbit around the Moon or Mars, or any asteroid, on the inner edge of the giant bicycle wheel. That will allow humans to spend more time in normal Earth-like conditions.

[insane_alien]

I still haven't heard anyone say my centrifuge idea would not work to attain one g gravity on the surface of the Moon or Mars.

 

That would be because there isn't anything wrong with it.

 

you'll notice that nasa uses centrifuges for training quite a lot to get steady >1G gravity.

 

one issue however is likely to be the size, you'll have stresses on the compartment due to the orientation of it and the gravity thats about as well as the rotation. ther might be technical challenges in achieving the idea, but none theoretically.

[Klaynos]

I'm not sure whether it would work.

 

If it's like a ferris wheel with slopped floors, I can't think of a situation where the sideways force would be able to balance against the downwards force to allow for a force just in the direction of your floor.