Why isn't NASA using artificial gravity for manned space travel?

[person123]

TL;DR

I'm curious about whether NASA not using artificial gravity in manned space travel is to maintain funding for zero gravity research.

Hi! I'm curious what your take on this is. I'm taking an introduction to U.S. Government course and my professor was discussing the inefficiencies of the public sector; the discussion on politics isn't relevant here but he did make an interesting point about space travel. He argued that the reason for NASA not using artificial gravity (in the form a rotating spacecraft ) for manned space travel was because those researching the effects of zero gravity want to ensure their job and funding for their work. Does this seem accurate to you? Are there other reasons you can think for it? I know essentially nothing about space travel and I would be curious on your views about this.

 

[jedishrfu]

In order to create artificial gravity, they would need to create a ring to walk around in. The ring size would be much larger than the vehicles they designed and so it’s comparative cost would be much greater And it would have to be assembled in space.

For these reasons, I think NASA was being quite practical and quite prudent able their engineering abilities and the safety of their astronauts more than anything else.

The wiki articles talks about these trade offs:

https://en.wikipedia.org/wiki/Artificial_gravity

 

[mfb]

Testing how astronauts react to lower gravity (like on the Moon or on Mars) would be a great research topic. Space agencies look into long-term missions to these places and we have no experience how the human body reacts to values between 0 and 1 g.

There was a concept for a centrifuge as ISS module, Nautilus-X - a few astronauts would have slept there. It was canceled as it was too complex and other things had higher priority.

 

[Vanadium 50]

I'm taking an introduction to U.S. Government course

From a conspiracy theorist? I'd drop the class and possibly transfer universities.

As mfb points out, people have looked into this. It is not trivial, requires new technologies, and is not cheap. They say $3.7B which is already a lot of money. At the same phase of development, JWST was expected to cost $500M. Using the same escalation, at launch Nautilus-X would cost $74B.

That's three years of NASA's total budget.
That's nine years of NSF's total budget.
That's twelve years of DOE's office of science budget.

 

[berkeman]

From a conspiracy theorist? I'd drop the class and possibly transfer universities.

LOL, that was my first reaction to his post as well.

Are there other reasons you can think for it? I know essentially nothing about space travel and I would be curious on your views about this.

They don't need to produce artificial gravity with the spacecraft when the astronauts can do that by themselves...

 

[mfb]

They say $3.7B which is already a lot of money. At the same phase of development, JWST was expected to cost $500M. Using the same escalation, at launch Nautilus-X would cost $74B.

$3.7 B was the estimate for a larger stand-alone space station, the ISS module was estimated to be much cheaper. But with one-of-a-kind devices cost estimates are always tricky.

 

[Rive]

He argued that the reason for NASA not using artificial gravity (in the form a rotating spacecraft ) for manned space travel was because those researching the effects of zero gravity want to ensure their job and funding for their work.

It is more like sailors are supposed to be able to swim: the smaller the ship the more.
Regarding space, we still has only some rafts. To be able to handle zero gravity is a must.

 

[DaveC426913]

In order to create artificial gravity, they would need to create a ring to walk around in.

AG can - in principle - be created much more economically than a giant ring. Two modules (eg. 1st stage tanks) linked by cables and spun will work.

Or just one long station.

Still plenty of engineering, but significantly less than a ring.

 

[jedishrfu]

Yeah, I was thinking of the movie 2001 A Space Odyssey where they built a giant ring.

 

[russ_watters]

Testing how astronauts react to lower gravity (like on the Moon or on Mars) would be a great research topic. Space agencies look into long-term missions to these places and we have no experience how the human body reacts to values between 0 and 1 g.

There was a concept for a centrifuge as ISS module, Nautilus-X - a few astronauts would have slept there. It was canceled as it was too complex and other things had higher priority.

It sounds like a worthy project to me. There is so much about operating at 0g that is problematic or adds complexity that even partial gravity would help with. That's in addition to the need to study long duration exposure of people to partial gravity if we're ever going to take the next steps in space travel -- both exploration and making it more user friendly for the general public.

 

[jackwhirl]

He argued that the reason for NASA not using artificial gravity (in the form a rotating spacecraft ) for manned space travel was because those researching the effects of zero gravity want to ensure their job and funding for their work.

Does this trope have a name? I've seen it before, usually about 'Big Pharma' suppressing one thing or another.

Artificial gravity is very interesting, but will be involve a lot of capital expenditure.

Here's a video about an ongoing project to design a facility with this capability, but there is a disappointing lack of discussion about funding. I don't think they have the backing to pull this off, but it isn't unfeasible, imho. If they got Bezos signed on they could definitely do it.

 

[Vanadium 50]

It sounds like a worthy project to me.

Are you willing to give up WFIRST (Now the Nancy Grace Roman Space Telescope) for it? What about the next Mars Rover, Perseverance? Maybe the Europa Lander?

The problem is that NASA has more "worthy projects" than it has money for. And if the solution is "just give NASA more money", it wouldn't change this - it would just be a different set of worthy projects that there is no money for.

 

[mfb]

Are you willing to give up WFIRST (Now the Nancy Grace Roman Space Telescope) for it? What about the next Mars Rover, Perseverance? Maybe the Europa Lander?

Give up SLS. That's $2.5 billion per year. $4 billion per year if Orion is scrapped as well. It's even in the same part of NASA, human spaceflight.
NASA can't make that decision, but Congress could.

 

[russ_watters]

Are you willing to give up WFIRST (Now the Nancy Grace Roman Space Telescope) for it? What about the next Mars Rover, Perseverance? Maybe the Europa Lander?

The problem is that NASA has more "worthy projects" than it has money for. And if the solution is "just give NASA more money", it wouldn't change this - it would just be a different set of worthy projects that there is no money for.

Probably Perseverance. The rovers have been a great bang for the buck, but there is a diminishing return in my opinion. But they are cheap.

Look, I'm mostly onboard intellectually with the idea that robotic science missions provide a lot more value for the dollar than human spaceflight. But The United States Is A Spacefaring Nation, and that means we need to have people in space, even if they are just hanging out in a hotel a hundred miles up just so we can say they are there. $3+ Billion a year is a lot of money to keep the ISS going Because We're The United States, but we do it Because We're The United States. Our lack of human spaceflight capability for almost the past decade was a national disgrace.

But we're at a crossroads. We're treading water, not swimming. The last several Presidents have had ambitious plans to go back to the moon and extend to Mars that weren't real because they didn't include funding equal to the plans. And the ISS is aging, and may need to be retired in the next decade or two, whether we want to or not. So one way or another, in the next decade or two we're going to have to decide for real what the next step is, if any.

If we're serious about a mission to Mars or commercial/tourist spaceflight in the next 20 years, experimenting with partial artificial gravity has a lot of value. And the fact that it evokes "2001" and a great many other hard science fiction space stories really is part of that value. Low-tech as it is, it's an eye-popping/game changing concept for how humans live in space. Right now, astronauts are intrepid pioneers who don't shower and drink soup out of a tube. But if you can take a shower and sit at a table and eat soup with a spoon? That's for everyone.

 

[gary350]

If someone makes anti gravity and Earth no longer has gravity we will all need to screw a BIG eye bolt into our yard and attach our self to them with ropes so we don't float off into outer space. Our houses will be floating around like blimps tied to eye bolts too. How will we drive our car to work that will be tricky?

 

[trainman2001]

Easy, all you have to do it run at a constant 1G or thereabouts acceleration. Rociante in "The Expanse" uses acceleration gravity. You accelerate at 1 G for half the trip and turnaround and decelerate at 1G in the other direction to stop at your destination. Now, the only bugaboo is what power and fuel source do you need to perform this magic act. Most SciFi seems to settle on fusion, but it may not be enough. Sounds like a matter/antimatter system. In other words, the devil's in the details. Even at 1/2 G would provide the physiological benefits to the travelers. It doesn't have to be Earth gravity. If going to Mars, it could be a value closer to Mars to acclimate the travelers to their new environment.

 

[CherylJosie]

Easy, all you have to do it run at a constant 1G or thereabouts acceleration. Rociante in "The Expanse" uses acceleration gravity. You accelerate at 1 G for half the trip and turnaround and decelerate at 1G in the other direction to stop at your destination. Now, the only bugaboo is what power and fuel source do you need to perform this magic act. Most SciFi seems to settle on fusion, but it may not be enough. Sounds like a matter/antimatter system. In other words, the devil's in the details. Even at 1/2 G would provide the physiological benefits to the travelers. It doesn't have to be Earth gravity. If going to Mars, it could be a value closer to Mars to acclimate the travelers to their new environment.

The machine guns, shrapnel, and radiation experiments were a far larger problem than AG for the crew of the Roci. Oh yes the political instability was also an issue. lol

 

[CherylJosie]

I think the larger question is where are we going with the space program? It seems that colonizing Mars is out of the question and we've got global warming plus pandemic here on Earth. AG in space seems like a purely hypothetical topic. I'm more concerned about preserving civilization now than providing AG for it in space. Without a stable base on the ground there's no space program let alone AG.

 

[hmmm27]

If someone makes anti gravity and Earth no longer has gravity we will all need to screw a BIG eye bolt into our yard and attach our self to them with ropes so we don't float off into outer space. Our houses will be floating around like blimps tied to eye bolts too. How will we drive our car to work that will be tricky?

Oh, I wouldn't worry about that much : the atmosphere will be gone in a matter of tens of seconds.

I think the larger question is where are we going with the space program? It seems that colonizing Mars is out of the question and we've got global warming plus pandemic here on Earth. AG in space seems like a purely hypothetical topic. I'm more concerned about preserving civilization now than providing AG for it in space. Without a stable base on the ground there's no space program let alone AG.

NASA was given a whole 0.49% of the USA Federal budget, this year. Civilization is in no danger from that quarter.

Colonizing Mars is hardly "out of the question", but I think we'd get farther at the end of the day, if we concentrated on putting facilities on/in small moons & asteroids for the time being, ie: access to raw materials without bitchy gravity wells, leaving the big balls of rock for the tourist trade (nothing wrong with that, of course). Phobos, for instance - tragic name notwithstanding - has a massive divot that faces Mars all the time, so there's your cosmic ray shielding already set up ; Ceres has water... lots and lots of water.

Barring breakthrough (and unanticipated) medical advances, AG is a must. Dust off those protractors.

On the other hand - if you simply cannot figure out how to attach a flag to something without the aid of gravity - there's a nice equatorial mountain range on the far side of the Moon, just begging for a tangential spaceport (about 50mi worth of 3g linear accelerator), so whatever floats your shuttlecraft.

 

[Dr Wu]

A return to the Moon seems the likeliest outcome from this POV, both in terms of cost and convenience. It's by far the nearest large celestial body to us; close enough as celestial bodies go for two-way communications with Earth to be uniquely conducted almost in 'real time'. If the Moon has accessible lava tubes, then in terms of research bases, that should put a lid on the radiation problem, at least for the time being. Of critical importance, of course, as mfb has already pointed out, the Moon used as a habitat will give us our first proper experimental take on how non-aquatic biology is affected by lowered gravity. If we can cope with Luna's feeble one-sixth pull - and there's no guarantee we ever will - then that puts Mars (and conceivably Mercury's polar regions?) on the map for the first time. But only being there; not getting there. Therefore, unless someone comes up with a substance like cavorite, or failing that some kind of exotic prophylactic, any thoughts of us engaging in zero-gee style crewed missions to Mars appear to be strictly for the birds, and likely to remain so for a depressingly long time. That's assuming, of course, we don't go down the road of '200l'-style carousels, revolving dumb-bells, and the like. So Luna it is, most probably. As with any seemingly insuperable problem, you start with the doable bits.

 

[mfb]

Several astronauts have been in space for a year or more - longer than a trip to Mars would take. They all have returned to Earth and recovered. Earth -> 0 g transit -> Mars is no problem. We don't know the effects of a long-term stay on Mars. Ascent from Mars could be quite stressful (as they are used to 0.4 g), and landing on Earth will be stressful.

 

[berkeman]

Several astronauts have been in space for a year or more - longer than a trip to Mars would take. They all have returned to Earth and recovered. Earth -> 0 g transit -> Mars is no problem. We don't know the effects of a long-term stay on Mars. Ascent from Mars could be quite stressful (as they are used to 0.4 g), and landing on Earth will be stressful.

Maybe we should patent a "running globe" for use on Mars. I did a patent search and it looks like it hasn't been patented yet. The faster you run, the farther up the globe you can run. Think of the royalties we could earn! Oh wait...

https://d3s3zh7icgjwgd.cloudfront.n...CircusphotographerCom-e1485783246469_Main.png

 

[Dr Wu]

Several astronauts have been in space for a year or more - longer than a trip to Mars would take. They all have returned to Earth and recovered. Earth -> 0 g transit -> Mars is no problem. We don't know the effects of a long-term stay on Mars. Ascent from Mars could be quite stressful (as they are used to 0.4 g), and landing on Earth will be stressful.

Not only would the assent from Mars pose a problem, but also achieving landfall there in the first place. Chris Hadfield's account (in An Astronaut's Guide to Life on Earth) of the travails he experienced after his six-month stint aboard the ISS tells its own story. For any astronaut to successfully land on Mars after a year long interplanetary flight would need to have the same infrastructure that currently exists on Earth already in situ on the Martian surface. Possibly this could be delivered by robotic means. Whatever, recovery time won't be overnight, even allowing for the kindly Martian gravity.

PS. What we need are some more Matt Damons

 

[mfb]

A trip to Mars doesn't take a year. 9 months on a low-energy trajectory, 6 months if you spend a bit more fuel, possibly even shorter. And 0.4 g is easier than 1 g. The astronauts might need to be careful for a while but it's nothing that would be a larger problem.