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I can't count how many science fictions stories I have read where someone is strapping on magnetic boots to walk in or on a space ship without gravity. How realistic of a solution is this? Just for reasons of mass I assume pretty much everything currently in space is Non-ferrous which also means non-magnetic.

Assuming for some reason (not sure why) you actually wanted to walk in/on a space ship/station without gravity would magnetic boots or something else be the best way to go?

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  • $\begingroup$ Related non-dupe Could magnetic “boots” be used to simulate the effects of gravity for asteroid ships? $\endgroup$ – James Jenkins Nov 17 '15 at 16:39
  • $\begingroup$ Yes, they would be practical, not so much for walking but for "anchoring yourself" at various work stations - currently astronauts on ISS just slip their feet under straps attached to "floor" relative to given work place. Unpractical for the simple reason that these straps are far lighter than the necessary ferrous pieces of floor. $\endgroup$ – SF. Nov 17 '15 at 17:03
  • $\begingroup$ I'm pretty sure I'd hate them boots if I were up there. Almost all sci fi is pretty bad for the critical reader. Makes me think of Monty Python's silly walks. $\endgroup$ – LocalFluff Nov 17 '15 at 19:26
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    $\begingroup$ I think the big problem you'd encounter is that spacecraft are usually composed of non-ferrous metals like aluminum and titanium, so magnets wouldn't stick. $\endgroup$ – 2012rcampion Nov 18 '15 at 10:30
  • $\begingroup$ @2012rcampion I think you could probably work that up into an answer. non-ferrous metals have a lower weight to strength ratio which makes them popular for space craft. Any possible of benefit (other than movie budgets) would be greatly offset by all that extra mass. $\endgroup$ – James Jenkins Nov 25 '15 at 15:25
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This turns out to be a pre-space-age thing. It's not really needed, most of the time it's perfectly fine to float around. On Skylab they provided an elaborate system of triangular grid floors and special shoes with triangular cleats to lock into them. The crew hated them and hardly ever used them.

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When body positioning is important (like for flying the robot arm), various types of foot restraints can be used, mostly simple straps. If you are riding the robot arm, there were also foot restraints.

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EVA folks also use tethers to secure themselves to work points.

But for just moving around, in or out of a space vehicle? Use your hands and/or push off with your feet (not recommended on EVA). Walking is highly inefficient in free fall.

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  • $\begingroup$ If you overlook the fine grid in the upper left of the Skylab assembly picture, a quick glance suggests that the cleats were about a meter across. No wonder the crew hated them! ;) $\endgroup$ – Russell Borogove Jun 8 '18 at 14:09
  • $\begingroup$ Yeah, it's the small grid. Probably not the best choice of picture. $\endgroup$ – Organic Marble Jun 8 '18 at 15:15
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As long as we use ultra-light materials in space, it isn't realistic. But even if we assume the space ship to be built of iron or steel:

You'd want the boots to simulate earth gravity towards your spacecraft while you are on an EVA to facilitate movement etc.

First, if you'd want that, you probably would line the whole suit with magnetic fibres so that the entire suit is being pulled towards the spaceship to simulate gravity on your whole body. The boots alone would just mean that your feet get pulled down while your body won't. I doubt that this would really help with working in a 0G envionment when just your feet get pulled down. Would feel a lot like in a water tank with weights around your ankles.

Second, to be viable this suit would not disengage and reengage like a magnetic lock that is visible in several movies everytime you try to lift your foot. It would simply be an always on like earth gravity - which you might have guessed by now - is also always on and would cause your suit to accelerate with 9.81 m/s² towards the spaceship. On the plus side, this would almost negate the requirement of training every day on a spaceship to combat muscle atrophy.

INSIDE a station, the easiest way to simulate gravity would be to rotate it. No need for anything magnetic around you to give you "gravity". Also inside you'd have the problem that you'd need one plane to be your "anchor". Otherwise you'd lift a foot and it would suddenly get pulled to the wall because that happens to be made of steel just like the "floor".

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    $\begingroup$ For movements it would be as impractical as walking on the bottom of a pool instead of swimming in it. I don't see how magnetic boots could help against loss of bones and muscles or any other medical microgravity problem. They would not put pressure on the spine nor relieve the eyes, head and heart from internal fluid 0G overpressure, nor keep dust and microbes from floating around in everyone's face. Maybe they help leg muscles and foot health a bit, but less than what purposeful stationary exercise would. $\endgroup$ – LocalFluff Dec 8 '15 at 16:09
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    $\begingroup$ @LocalFluff: I can see one purpose - lightweight magnetic shoes and small ferrous areas in front of "workstations". Currently astronauts hook their feet under straps running through the "floor" of such "workstations" to anchor themselves. Magnets would be more "handy". $\endgroup$ – SF. Dec 8 '15 at 17:39
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it could screw around with all the electronics, and would require the ship to have an outer layer that is ferromagnetic,

but beyond that, it would need a constant source of energy (assuming they're electromagnets) which could be a big issue if that energy runs out

but if you can get around that then I would think they would be rather useful

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