Simulated One Gravity Living on the Moon and Mars With a Supertrain

The moon has one-sixth the Earth’s gravity and Mars gravity is 38%. There will be negative health impacts for people to live for extended periods at lower gravity. In space stations, we can spin the station to get the desired gravity.

Dr. Joseph Parker presents a gravity solution for living on the moon or Mars. We need to have people live in one gravity pods on a circular hyperloop like track.

A one-kilometer radius track going at 360 kilometers per hour provides on one G. The actual moon or Mars tracks would have pods or trains going a bit slower and on an angle to get the right gravity. It is a 70-degree angle on Mars.

People and their children would live on these large trains. A smaller train will dock with the habitation train and they will load supplies. People will go onto the docking train to go to work in the lower gravity and then return to one G living and sleeping.

This train solution aligns with Elon Musk’s development of the Boring company and Hyperloop.

88 thoughts on “Simulated One Gravity Living on the Moon and Mars With a Supertrain”

  1. For those interested in the math, this will work in Excel:
    Mars Angle = DEGREES(ACOS(3.72/9.81))
    Mars Angle = 67.72 Degrees
    Assuming a 500m radius (1 km diameter) the velocity of the train would be:
    Mars velocity for 1 km diameter = SQRT(SQRT(9.81^2 – 3.72^2) * 500) m/s
    kph = velocity * 3.6 = 242.53 kph
    mph = velocity * 2.2369362920544 = 150.7 mph

    Moon Angle = DEGREES(ACOS(1.625/9.81))
    Moon Angle = 80.47 Degrees
    Moon velocity for 1 km diameter = 69.55 m/s
    kph = 250.38
    mph = 155.58

  2. Sorry guys. You are going to have to make special exercise equipment and spend a lot of time at the gym….till we can make synthetic gravity without accelerating humans.

  3. A simpler, cheaper experiment would be a couple of cans at the ends of a retractable tether (umbilical cord), each holding a small population of mice. With enough length, cans could be at different Gs by attaching them at different distances from the center.

    When needed, the cans can be reeled in for cleaning, maintenance and population swaps.

    Some cans could hold critters with shorter life cycles.

  4. What is needed is a new culture of work.

    Number one–I want all structures to be able to support all weight at Earth gravity levels–overbuilt.

    All forklifts must operate dead slow. The weight might have lessened–but that mass hasn’t left. Go too fast–and you have a flying boulder leaving the forks to plow into things

  5. In my case it’s probably because I fractured vertebrae snow tubing when I was 50. I suppose that’s a lifestyle problem, though…

  6. Sounds to me like a classic “small college grad-school project”. Seriously. 

    ⇒ F = v²/r
    ⇒ 9.81 = v²/r … what’s v?
    ⇒ v = √( 9.81 r )

    Let’s make r = 1,000 m.

    ⇒ v = √( 9810 )
    ⇒ v ≈ 100 m/s ( × 60 × 60 ÷ 1,000 = 360 km/h )

    OK. Nice. Now as a grad-school project, learn a few 3D graphics programs, and put together a few stick-models of a pod. And a track. Choose a suitable looking bunch of ray-trace materials (“cement”, “glass”, “steel”) and let the renderer mock up a few scenes.  


    And the 70° bbb-bb-b-bûllsnot? That’s simple enough … just have to unravel the trigonometry of vectors for gravity-on-Moon (⅙ G) and the centripetal factor. CF = 9.81 m/s², GF = 1.64 m/s². Resultant = √( 9.81² ⊕ 1.64² ) = 9.94 m/s² (somewhat larger than 1 G).  

    ⇒ atan( 9.81 ÷ 1.64 ) = 80.5° (not 70°) 

    Oh, is it Mars?  

    ⇒ atan( 9.81 ÷ 3.71 ) = 69.5° (close to 70°) 

    Just saying, folks.  
    This is barely rocket-science.
    Weak physics.


  7. > The MAJORITY of humans suffer from back pains.

    In old age, sure. If you’re having back problems below middle age, it’s most likely because your posture is bad, you’re sitting hunched over your smartphone/pc/etc all day, you don’t exercise enough so your core is weak, and maybe you’re overweight. Those are lifestyle problems, not gravity problems. If you’re having back problems in middle-age, that’s probably all those things that you did wrong (or didn’t do) in your younger years coming back at you.

  8. Pretty sure you can, just not you usual Earth variety. Lunacrete may be one example:

    EDIT: Ok, on 2nd read, Lunacrete still needs to be cast in a pressurized environment. But after it’s cast and hardened, I think the pressure can be removed. Steam injection has been proposed as an alternative solution, and I’m pretty sure one can come up with a different chemistry that would work in vacuum.

  9. We now realise your hinted at accusations are correct. The so-called Moon landings were actually on Mars. The real moon can’t be landed on because Mr Squiggle hasn’t given us permission.

    The so-called Apollo Project Saturn 5 rocket was actually just a giant sextoy made for JFK, and after his death they sent the astronauts to the film set made on Mars using Roswell UFO tech.

    You found us out.

  10. Maybe sleeping in 1g does help your health relative to sleeping in 0g (or 0.16g)
    X is bad doesn’t disprove that Y is worse.

  11. The suggestion is of course absurd.

    The solution is the moon as a temporary destination and mars as not one at all for long term colonization.

    Robots not humans will colonize the solar system & build a civilization there.

    Genetic engineering to enhance survivability is another option but it will require modification to the extent that one is no longer human & by the time this is possible neural grafting will be practical too.

  12. First of all, nothing seen on television at the time, regarding the lunar landings, was in “real time”. It was all prerecorded. Live shots from the moon could not have been possible at that time.

    It’s one thing to drop an object, but it’s another thing to throw an object into the air. If one of the astronauts could, with a measured effort, throw a hammer upwards for about six feet, how far would the hammer, with the same measured effort, travel upwards on the moon that has one-sixth-the-gravitational-pull-of-Earth?

    Let’s say an astronaut wearing a “200 pound” spacesuit could jump at least one foot above the ground on Earth. How high could the same astronaut wearing the same “200 pound” spacesuit jump above the surface of the moon with one-sixth-the-gravitational-pull-of-Earth?

    Even a “millenial” could do the calculations, yet nothing like these examples were ever performed.

    Moreover, at no time was a 360° panoramic video ever taken of their location on the moon. Can you imagine someone making the effort to attain a location that had a particularly beautiful view without taking a panoramic shot of that view, especially if they were ON THE MOON? Yet, all that was done was very limited shots never varying the locations.

    Even more odd were the perfectly-focused and -centered photographs taken by stock Haselblad cameras attached to the front of the spacesuits, the viewfinders of which could not even be seen from inside the spacesuit helmets.

  13. It was confusing why it was proposed and got funded, when the rotational approaches seem vastly easier and reliable.

  14. Brian, the concept is called a “Variable Gravity Research Facility” (VGRF) One design is a truss similar to the ISS central truss, but stronger, with modules you can attach at variable radii from the center. The whole truss rotates end-over end using thrusters and gyros. Then you can put people, plants, lab rats, etc. aboard, and observe the effects. Your solar arrays would be attached at the center, and pivoted to keep facing the Sun. This is basically the inverse of the current space station.

    Various arrangements have been studied:

  15. Sleeping in 1g doesn’t help your health. We know this from hospital and nursing home patients who spend extended time in bed. We also know sitting all the time is bad for you, but not as bad as bed rest. The point seems to be forcing your heart and muscles to work harder. Standing is better than sitting or laying down, since your muscles have to work to keep you upright, and the heat has to pump harder to overcome the vertical pressure drop. Walking, running, and other exercise are even better, they give your system more work to do.

    What we don’t know is what combination of activity and natural + artificial gravity is enough.

  16. I Propose a variable gravity research station.

    Step 1: make a lunar space elevator.
    Step 2: build a variable gravity simulation environment to be the lunar space elevator counterweight.
    Step 3: raise and lower the counterweight to simulate whatever gravity you want. Move away from the moon to get 1/3rd a g, move towards the moon to get 1/6th of a g.

    We can keep people there for say a year or three to demonstrate that 1/6th a g is safe. I can’t think of a simpler way to test 1/6th of a g.

    Did I forget to mention that we can only build this with SLS?

    Can I haz grant moniez?

  17. Yes indeed the lunar space elevator is a wonderful thing. You can do it with fixed width kevlar ribbon instead of making annoying tapered ribbon. You just need to somehow build up a counterweight but that isn’t too hard. Once you have a very basic elevator in place you would send up Moon built Aluminum shipping containers full of regolith slag. Once the first container is up you send the second, etc. Eventually you will expand to multiple up and down lines as your counterweight is large enough and far enough out to provide adequate centripetal acceleration to keep the lines taut (this is a problem because the moon rotates very slowly- being tidally locked to Earth).

    Why a lunar space elevator? Well because you can ship bulk goods to the Moon and land them without entering the bottom part of the Moon’s gravity well. This means that you can get goods from orbit to the lunar surface with relatively low thrust engines.

    The Moon is actually ridiculously lucky in that it is right sized for space elevators without exotic materials (tens of thousands of kilometers of high quality nanotubes), no moons orbiting it (Phobos, Deimos), no pesky weather to interfere… pretty nice place for an elevator.

    Not that I think about these things.

  18. “There will be negative health impacts for people to live for extended periods at lower gravity. ”

    That’s a nonsensical unscientific and baseless affirmation.

    There MIGHT BE. There might be NOT.

    We simply do not know.

    Because noone EVER lived for extended periods at lower gravity.

    We have data points for 1G and 0G.

    We know that 0G has several negative health impacts. We also know that 1G ALSO causes negative health impacts, specially in us, straight walking bipeds with big heads known as humans. The MAJORITY of humans suffer from back pains.

    We have NO data points, no research done at 0.1, 0.3, 0.5, 0.8 G.

    To extrapolate ANYTHING knowing only what happens in complete absence or in our natural environment is totally bogus science.

  19. Mat… Also not to mention some of these places don’t like wind currents. Travelling that fast on some of these places could cause more frequent dust storms. Hamper all kinds of other plans in the neighborhood there. Everthing has to be considered. Homework isn’t for everybody. Dear Dr.

  20. Mat… People think its easy to send items or to refine rocks on the moon or mars. Its not. Can’t just go to those places and expect to build big structures such as artificial g trains and shopping malls right away. Think small scale that will get them by at first. Waste of time and resources to build all that. Plus what shields the people from solar radiation. Love. If they want to risk such a foolish endeavor. Put it in a central tether from center cable to center and outer module habitat inside a crater. As the meteor has already made an almost circular track for you. Have 17 feet of top area of module covered in surface dirt. Sides will mainly already be protected horizontally by crater rim. Central motor like bucket on a string. Rotated like a bucket on string within a crater. Spinning inside as a top spins. Pick a crater 100 meters across or more. 50 meter cable to the centre. Wheel or wheels going around the whole module. To lode people from the end. Would look something like this. @————————(lllll). At being centre of crater. Dashes being cable. The rest being the g module. All inside a crater. Also. Sorry for repeating some thing over again. Echo effect.

  21. Without atmosphere we could use magnetic cannons for launch. And requirements for space elevators are lower on Moon, enough to be doable with current technology.

    Moon allow us a fixed point on space where we could make IRSU and accumulate technology on one only spot easily.

    On Space, probably L4/L5 are good points for something similar, but we will need to extract materials from other places.

  22. I imaginated this like a disc, , more than a train. Exterior walls are bottom floor from inside perspective, and walls had an inclination proportional to the composed grativy (real + centrifugal, that it’s a vector which angle goes from near 90 up to 0 in the center).

    Exterior borders can levitate though inductrack+superconductors like technology while in the center regular rails could exists for emergency stop.
    Without air, and regular temperature magnetic levitation, and superconductors must be cheaper than on Earth and very smooth movement so very “1 gravity” environment (at bottom on the ring)

    Stairs would be very twister from close 90 up to 0 to the center (something like stairs at botton, curved corridor close the center.

    Buried on the ground or on lava tubes, with very huge radiation protection, that environment could allow permanent settlement if we want.

  23. As others have pointed out, we don’t know the biological effects of gravity levels between 0 & 9.8 m/s^2, & we need to test the effects. The surface (or cloud level) gravities of solar system bodies cluster around values differing by ratios of 0.4 (or 2.5). Jupiter is about 25 m/s^2, Venus Earth Saturn Uranus & Neptune are close to 10 m/s^2, Mercury & Mars are marginally less than 4 m/s^2, Luna, Io, Europa, Ganymede Callisto & Titan are close to 1.6 m/s^2. (Coincidence? Probably.) This means we only need to test at 4 & 1.6 m/s^2 to cover the 10 largest worlds with solid surfaces in the solar system.
    So one moon base & one rotating habitat giving 4 m/s^2 pseudogravity is all that is needed for testing the biological effects of reduced gravity
    If it is worth checking if there is any benefit to g levels between 0 & 1.6 m/s^2, that can be done near the center of the rotating habitat

  24. Mat… Would lose all bone density and muscle mass just in the time building the infastructure for the track.

  25. If there are any differences between centrifugal acceleration and gravity, they’re pretty subtle, and the guy who proves them wins the Nobel prize. The only practical difference is the Coriolis effect, which you can minimize by using a reasonable radius.

  26. Too much of a waste.
    Instead of one lone train “car” circling the loop, just connect enough cars to cover the entire tack surface and construct your city on top of the cars,

  27. LOL, now I can’t help but hear it with that voice mein Führer, I ‘m sorry Mr President!

    What I wanted to convey was the need of more information and why we should be planning to extend human activities in several places at once, to know more.

  28. All the disadvantages of a 30 RPM centrifuge, with the added problems of the acceleration being intermittent, high power demands to work, and the structural loading constantly changing.

    I’ve seen bad ideas come out of NASA, but this was by far the worst I can recall. I wasn’t joking when I said the guy who came up with it had probably been told to produce a concept that would be guaranteed to be rejected.

  29. Mat… If heavier clothing and helmets aren’t enough a toned down version of an artificial g item like the one fighter pilots use to train on could be used. All that infastructure for a train is a joke. Could have a room that people could go to take turns using the gravity simulator. Called The Artificial G spot. Or T.A.G.S. room.

  30. We should test it on earth too just to validate the basic principles. We could make a very long, straight track and run the trains very slowly. This would let us move from TRL 3 to TRL 4.

    Is there a URL where we submit these ideas?

  31. Has all the makings of a retro 70s sci-fi B movie.

    Kind of like “The Big Bus” meets “Ice Pirates”.

  32. Better yet we can spin move weights towards or away from the center of the drum to speed or slow the rotation. We can use this to store energy and make the habitat a giant battery.

    Once you can put “battery” in the NASA ppt your funding doubles.

  33. Apart from the hammer-feather experiment i’m pretty sure that landing there demonstrated 1/6th g, bouncing around with a 200lb space suit demonstrated 1/6g and going single stage to low lunar orbit demonstrated 1/6th g.

  34. Wrangle a near earth asteroid or actually get great space infrastructure and we can do whatever we want. As Bane says in Inception – You can’t be afraid to dream bigger

  35. Not until you make some computer animated pictures and video. Plus you have to follow procedures and submit the proper forms to NASA NIAC and get it accepted. NASA is a bureaucracy

  36. Then make 100m radius horizontal, sloped rotating drums. You can climb in at the center and take the ladders down to 1g. The rotation speed and the slope of the floor mimic 1g even with the moon’s weak 1/6th g pulling you laterally. You can spend half a day in one full g and it will cost less than a train.

    Can I haz my fat NASA ppt moniez?

  37. Its not too early to have design ahead options. It is better to think and work options. Plenty of people can chip in. Iterate and refine. Not good to have the problems and wait for them to get huge and then have many year lags to work on mitigation. That is the air pollution approach.

    Also, try to test and figure out what might be or might not be problems.

    Also they will be on the moon for extended periods before we could build this system. This would still take 15-40 years to happen.

    Probably have to be at the 1000 person stage to have the infrastructure and scale for these things

  38. Agreed. We need to explore biological solutions to allow people to live comfortably in extra-terrestrial environments.

  39. Please, not that reciprocating nightmare. The guy who designed that must have been tasked with coming up with the worst possible way of simulating partial gravity, in order to make sure the idea would be rejected.

  40. Clearly, we need more data points.

    Build a Moon base for testing long trips there. A Mars base would be needed too, for checking the effects of 1/6 and 1/3 G.

    A bolo space station as well, for checking the differences between centrifugal force and gravity. I think there is none, but you can never be sure until you test it out.

    And finally, make a fully Earth-like rotating environment in space, where you can check long term living and gestation.

    But I’m sure someone will test animal and human gestation in space regardless of plans.

  41. Totally agree. The notion that if this is a problem that we can’t find a biological solution is crazy. There are easier ways to fix this than crazy trains.

  42. Dear God No.

    Again how do I get on this fat ppt gravy train? Clearly I have made the mistake of meaningful employment.

    On the moon gravity is low enough that you can do some interesting things that are barely possible on Earth. Human powered flight comes to mind. Lava dome vertical cities where people fly on their own power.

    So less gravity doesn’t mean less exercise or less impact. And honestly it is too early to start designing countermeasures for lower-g environments. Let some people live on the Moon for a while first.

  43. The B330, per some numbers I’ve seen, about $125 million each. (I don’t know, this *may* be the price in orbit, not at the launch pad.) Let’s just multiply by three for the total system cost, add the launch cost, and, up and running?

    A bit under a half billion dollars. For the overkill version.

  44. It would have to be the former, as gravity has effects on a cellular level, there isn’t any practical way to counter its effects on Earth that doesn’t potentially have greater and confusing biological effects.

    Let’s see, what would such a system consist of? I would say two Bigelow modules connected via a redundant tether system, and a docking/ power module in the center. One of the modules would be at the appropriate distance for lunar gravity, the other for Martian gravity. You’d want an elevator running along the tether.

    Two B330 modules would probably be overkill, but let’s go with that; They each mass about 23 metric tons. I’ll figure that covers the power module, too, as the B330 is meant to be self-contained.

    Docking and elevator? Probably masses about the same as a Dragon capsule. 4.2 metric tons.

    Radius (to the center of the ‘Mars’ habitat) of 86m at about 2 RPM. Radius to the center of the ‘Lunar’ habitat 37m.

    To make things balance you’d really want the ‘Lunar’ module to be 2.3 times more massive than the ‘Martian’ module, but that’s absurdly wasteful of mass. Instead you’d continue the tether out way beyond the ‘Lunar’ module, to reduce the counterweight mass. If you put the counterweight at 1km, you’re at about 1 metric ton, more reasonable.

    Rounding up to account for the tether, 60 metric tons. How convenient, it all fits in one Falcon Heavy payload. Maybe we could use the fairing for a counterweight? $90 million in launch costs.

    Gah, text limit…

  45. While a microgravity environment is clearly deleterious to human health, we really don’t know if the hypogravity of the Moon or Mars will also be harmful to human health.

    Because of their strength to mass ratios, small animals on Earth, including our tree living ancestors have lived in a lunar-like gravitational environment for hundreds of millions of years.

    And even if it is harmful to human health, rigorous exercise and simple weight vest might be enough to sustain Earth-Man or Earth-Woman health and strength on the surfaces of the Moon and Mars.

    Once we have a simple outpost on the lunar surface, we can leave people on the Moon for a year a two to see if there are any negative health effects as far as low gravity is concerned.


  46. We need to find a biological solution to this. I assume there must be a combination of two hormones that inhibits and stimulate bone and muscle production as a response to stress. Find a drug that does something similar.

  47. Seems like a waste not to extend the habitat all the way around the circle, instead of leaving most of the track empty at any given time.

  48. So a rotating habitat in low earth orbit with different rotation or some kind of counter-gravity system here to simulate lower Gs. How would what you are proposing work? Ballpark cost.

  49. What we need first is some testing too see what the impact of low gravity are. We know micro-gravity does have some small effects over a year, and two or three years might be bad. So let’s create a light spinning space station focused on physical effects of lunar or martian gravity. You need a habitat module, a long stiff boom (maybe a 100-200 m) – put solar cells on that, gyros, a counterweight, and a rocket for spinup and spindown. I bet it would cost a few $B … but it is an important mission since we will need artificial gravity to make space travel more healthy and more comfortable beyond the moon.

  50. No, speaking as somebody who watched the moon landing in real time, nobody has noticed that, because it wasn’t true. You could literally see the astronauts bouncing around in slow arcs due to the lowered gravity.

  51. The thing is, we don’t *know*; We only have two data points right now: 1G, enough. 0G, not enough. We have no idea the shape of the curve in between.

    There could be a threshold acceleration that’s enough for good health, it could be linear, no idea.

    I’ve been saying for literally decades that we need a rotating habitat to do long term partial gravity testing. It’s kind of important to know before we start colonizing space.

  52. Has anyone ever noticed that, in none of the videos alleged to have been made on the moon, no demonstration of the “one-sixth-the-gravity-of-Earth” was ever made?

  53. On my website,, I describe an approach to addressing the hyoogravity issues which could be implemented with the very first habitat placed in the Moon. It would address both adult crew health as well as determining the artificial gravity Rx for healthy gestation and childhood. These approaches is described here:

    An indoor centrifuge used four hours a day at full gee would make it likely that crew could, at a minimum, extend their stay and so reduce rotation costs and more importantly reduce the risk of loss of crew during rotations. Being thus available, it could be used for the gestation studies using a series of animal models.

    True, an indoor centrifuge might not be sufficient for healthy gestation and childhood. But until we try it, delayed schemes requiring tremendous amounts of mass and small living spaces should not distract from near-term approaches that might be sufficient.

  54. Too much fuss to live on another gravity well.

    Make a free fall spinning space station instead, go to planets only in tour of duty, to build and repair mining and factory machinery or to do research/tourism.

  55. I always thought of sleep pods in a large track that spun around. That way you have 1G or so every 8 hours.

Comments are closed.