Factories in Space(factoriesinspace.com)
factoriesinspace.com
Factories in Space
https://www.factoriesinspace.com/
19 comments
I don’t understand how it’s even remotely feasible to move dirty industry into space? It’s hard enough to build industry on Earth. Where would the biproducts (dirt) go? Wouldn’t it be far easier to make factories cleaner on Earth? This sounds like someone who has now truly lost the plot.
> Where would the biproducts (dirt) go?
On the website, they suggest that these byproducts, i.e. waste, could effectively be dumped into space, where the solar winds would carry it out to the asteroid belt.
I have no expertise to determine if this would ever be viable, but seems like they do at least answer this particular question of yours.
On the website, they suggest that these byproducts, i.e. waste, could effectively be dumped into space, where the solar winds would carry it out to the asteroid belt.
I have no expertise to determine if this would ever be viable, but seems like they do at least answer this particular question of yours.
I guess that could work, I did not think of that. Not sure if it greatly improves viability but venting into the solar winds I guess could be an option. At low earth orbit wouldn’t most material fall back down to Earth, it’s not like they’d be vending hydrogen. And a very high Earth orbit would incur even greater costs of getting material into space. It still seems bananas.
Edit: I checked and solar wind starts at 60K km so there is no solar wind at LEO and 60K km is way beyond geostationary where it is already considered too expensive to bring things back to Earth.
Edit: I checked and solar wind starts at 60K km so there is no solar wind at LEO and 60K km is way beyond geostationary where it is already considered too expensive to bring things back to Earth.
The better bet is to process raw materials in space and send refined products down to earth. Would you rather have strip-mining and smelting occurring in space or on earth? Daniel Suarez had a lot of fascinating ideas in Delta-V
> Would you rather have strip-mining and smelting occurring in space or on earth?
I assume you mean "on the moon or on earth" since you can't really mine in empty space. The process of either (without air, for a start) would make them so different as to be incomparable.
Mining on the moon would have so many expenses associated, that you could spend the same amount making earth-based processes cleaner. The issue is that it's economical not to do so, so earth processes are dirty by design and due to lack of regulation.
I assume you mean "on the moon or on earth" since you can't really mine in empty space. The process of either (without air, for a start) would make them so different as to be incomparable.
Mining on the moon would have so many expenses associated, that you could spend the same amount making earth-based processes cleaner. The issue is that it's economical not to do so, so earth processes are dirty by design and due to lack of regulation.
I wonder how hard it would be to mine an asteroid, and then send the refined materials back to Earth from the asteroid belt. Sure, the initial trip would take a while, but after the initial package you could just keep shipping them every few weeks for a consistent supply.
It's not bananas. What's bananas is the idea of getting all your raw materials from mines on the Earth, launching those to space factories, then sending the finished products back to Earth.
Obviously, the goal is to do the mining in space (moon, asteroids, etc.), and then use those raw materials in space factories.
Obviously, the goal is to do the mining in space (moon, asteroids, etc.), and then use those raw materials in space factories.
I had the same questions! But again, this is where my knowledge fails me. For example, if you release C02, how far away from earth would you need to be for it to not get caught in Earth's gravity?
Still, it's a fascinating idea.
Still, it's a fascinating idea.
Anything within Earth's sphere of influence [1] (about 90000 km) will initially be in orbit around Earth. Unless you give it a kick that puts the highest point of the orbit further away from earth than that.
Unless you shoot stuff away with railguns, the relevant question might be "at which point are solar winds a bigger factor than drag". I guess it's highly dependent on the exact gas. We lose Helium that way from earth (buoyancy brings it up, where solar winds catch it), so at some height it should work for CO2.
It only really works for gases though, and then only for things that stay reasonably gaseous in orbit (low pressure and large temperature swings). For any solid or liquid you have to worry about it crashing into you on one of the orbits, and at orbital speeds tiny things can impact with a lot of energy.
1: https://en.wikipedia.org/wiki/Sphere_of_influence_(astrodyna...
Unless you shoot stuff away with railguns, the relevant question might be "at which point are solar winds a bigger factor than drag". I guess it's highly dependent on the exact gas. We lose Helium that way from earth (buoyancy brings it up, where solar winds catch it), so at some height it should work for CO2.
It only really works for gases though, and then only for things that stay reasonably gaseous in orbit (low pressure and large temperature swings). For any solid or liquid you have to worry about it crashing into you on one of the orbits, and at orbital speeds tiny things can impact with a lot of energy.
1: https://en.wikipedia.org/wiki/Sphere_of_influence_(astrodyna...
The more I look into it the less feasible it looks. My initial assumption is reflective of the peer comment that anything remotely heavy won’t have enough solar wind drag to get it out of Earths gravity well.
Just to be in the solar wind alone you’d have to be outside the magnetosheath ~60K Km at its closest point, 35K Km is geostationary orbit which costs $10K kg to get to with falcon 9. And now you’d have to send up a whole falcon 9 in order to bring the non byproduct mass back to Earth which would defeat the purpose of venting CO2 to begin with. For those who don’t know it takes roughly the same delta V to bring things back down as it took to send them up.
Just to be in the solar wind alone you’d have to be outside the magnetosheath ~60K Km at its closest point, 35K Km is geostationary orbit which costs $10K kg to get to with falcon 9. And now you’d have to send up a whole falcon 9 in order to bring the non byproduct mass back to Earth which would defeat the purpose of venting CO2 to begin with. For those who don’t know it takes roughly the same delta V to bring things back down as it took to send them up.
I don't know the answer to that.
Though I'm wondering: If manufacturing were done on the moon, would it be safe and feasible to haul some wastes to the lunar equator during the cold of night and let it burn up when daytime temps naturally exceed the boiling point of water from solar power alone?
Though I'm wondering: If manufacturing were done on the moon, would it be safe and feasible to haul some wastes to the lunar equator during the cold of night and let it burn up when daytime temps naturally exceed the boiling point of water from solar power alone?
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I wonder what the impact would be on astronomy, whether space based or terrestrial?
I've come to the opposite conclusion, that taking heavy industry off planet is a godsend, because it allows capitalism's stagnating growth curve, fuelled by resource extraction with no regard to externalities, to plausibly continue indefinitely, with no environmental consequences - and the wealth poured back onto earth.
Heavy industry will never move to space because it doesn't make sense economically. The main reason is that they are made in huge quantities that make it impossible to transport. Space elevators are pretty limited in quantity, think of them as a single rail line.
Concrete is most made material and its components come from Earth. It is used on Earth. It is made in such quantities that it is produced locally because it infeasible to transport it long distances. Wood comes from Earth, used on Earth, and makes no sense to manufacture in space.
Chemical industry is another good example, where a lot of the source materials come from Earth (nitrogen, petroleum, gas). All of the processes are designed to work in atmosphere and under gravity. My guess is that nitrogen-based chemicals will be shipped to space for a long time.
Steel is made in huge quantities, with ore trains, ore ships, and giant steel factories. My guess is that even had a free iron asteroid in space, that wouldn't make sense to mine it because getting the results down would be too expensive.
Also, there is a lot of large-scale manufacturing that wouldn't make sense to move because the result is used on Earth. Ship building is a prime example where building anywhere other than next to body of water doesn't make sense. Complex objects also have a lot of parts which means shipping them to space or moving the whole supply chain.
The exception is industry being used for use in space.
Concrete is most made material and its components come from Earth. It is used on Earth. It is made in such quantities that it is produced locally because it infeasible to transport it long distances. Wood comes from Earth, used on Earth, and makes no sense to manufacture in space.
Chemical industry is another good example, where a lot of the source materials come from Earth (nitrogen, petroleum, gas). All of the processes are designed to work in atmosphere and under gravity. My guess is that nitrogen-based chemicals will be shipped to space for a long time.
Steel is made in huge quantities, with ore trains, ore ships, and giant steel factories. My guess is that even had a free iron asteroid in space, that wouldn't make sense to mine it because getting the results down would be too expensive.
Also, there is a lot of large-scale manufacturing that wouldn't make sense to move because the result is used on Earth. Ship building is a prime example where building anywhere other than next to body of water doesn't make sense. Complex objects also have a lot of parts which means shipping them to space or moving the whole supply chain.
The exception is industry being used for use in space.
You mean: “and the wealth poured back into Bezos pockets”.
His entire series of enterprises has been about complete vertical integration. One part of why his favorite show ever is The Expanse.
Just curious, what does vertical integration have to do with The Expanse?
The entire show is about political tensions that result from expanding corporate dominance and private ownership into industrial heavy mining operations like those out in the Belt, with all the attendant cost-cutting and consequent torture of the peons that that entails. Reminds heavily of stories heard from within Amazon warehouses.
Amazon's push to dominate retail markets via Basics, etc., and the anti-competitive practices he enables, only serves to portend an obvious conclusion that Bezos wants to own not just the marketplace but every component of goods production.
Amazon's push to dominate retail markets via Basics, etc., and the anti-competitive practices he enables, only serves to portend an obvious conclusion that Bezos wants to own not just the marketplace but every component of goods production.
Gotcha. It is also one of my favorite shows(and I am far from a space theme enthusiast), but I think I focused more on the protovirus and what not, I should go back and re-watch it again!
We have to start by assembling in space first. SpaceX's Lunar Starship is a little bit like that. They have to launch tankers to orbit and refill the lander.
I can imagine someone making rockets from multiple separately launched parts that are then assembled in space. It would allow to use well tested rockets to launch smaller parts instead of trying to build a huge rocket at once.
I can imagine someone making rockets from multiple separately launched parts that are then assembled in space. It would allow to use well tested rockets to launch smaller parts instead of trying to build a huge rocket at once.
At this point it isn't just SpaceX's Starship, but in general the direction Artemis is heading in, since the secondary lander design (from Blue Origin, Lockheed Martin et al) that was recently chosen also uses in-space refueling and is designed with Lunar ISRU in mind.
Shelby finally retiring has been a great boon for NASA's human space exploration programs.
Also, technically the Lunar Gateway would fit your second point, considering that it's split into a separate habitation module and power+propulsion element.
Shelby finally retiring has been a great boon for NASA's human space exploration programs.
Also, technically the Lunar Gateway would fit your second point, considering that it's split into a separate habitation module and power+propulsion element.
> We have to start by assembling in space first
You need to solve the material-cost problem first. Either a space gun / elevator or ISRU. Otherwise, assembling on the ground is cheaper for everything but the most massive objects. (At which point a constellation or fleet usually makes more sense.)
> would allow to use well tested rockets to launch smaller parts instead of trying to build a huge rocket at once
Bigger rockets have moderate economies of scale. Optimising for a particular launch vehicle doesn’t make sense in the long run.
You need to solve the material-cost problem first. Either a space gun / elevator or ISRU. Otherwise, assembling on the ground is cheaper for everything but the most massive objects. (At which point a constellation or fleet usually makes more sense.)
> would allow to use well tested rockets to launch smaller parts instead of trying to build a huge rocket at once
Bigger rockets have moderate economies of scale. Optimising for a particular launch vehicle doesn’t make sense in the long run.
ISRU - In-Situ Resource Utilization
The farther humans go into deep space, the more important it will be to generate products with local materials, a practice called in-situ resource utilization.
The farther humans go into deep space, the more important it will be to generate products with local materials, a practice called in-situ resource utilization.
We’ve had space assembly for decades, just look at the ISS which both consists of many modules and used regular fuel deliveries to maintain orbit etc.
Manufacturing seems possible but is several orders of magnitude more difficult because many processes on earth simply aren’t viable without access to earths vast array of manufacturing infrastructure, organic chemicals, or even gravity.
Manufacturing seems possible but is several orders of magnitude more difficult because many processes on earth simply aren’t viable without access to earths vast array of manufacturing infrastructure, organic chemicals, or even gravity.
Check out "3D Printing in Zero G" experiments on the ISS for the origin story of space manufacturing:
https://www.nasa.gov/mission_pages/station/research/experime...
The company "Made in Space, Inc" responsible for creating the 3D printer, since acquired by Redwire. https://en.m.wikipedia.org/wiki/Made_In_Space
The company "Made in Space, Inc" responsible for creating the 3D printer, since acquired by Redwire. https://en.m.wikipedia.org/wiki/Made_In_Space
I was just thinking that some manufacturing processes and research techniques require deep vacuum that needs very expensive equipment on earth, but comes for free and in effectively unlimited volume in space.
Also we only need a small manufacturing-capable space station to build a larger space station out of materials mined from asteroids.
Also we only need a small manufacturing-capable space station to build a larger space station out of materials mined from asteroids.
To get deep vacuum, you either need a very high orbit, or one of these: https://en.wikipedia.org/wiki/Wake_Shield_Facility
Seems like 3D printing organs in space would be really useful and might make financial sense given their importance to people.
Any particular reason to believe that "in space" would make 3D printing of organs substantially easier?
Because gravity is a bitch when making squishy things. They like to collapse under their own weight before they can harden. Imagine a pipe that is rigid when fluid is flowing though it, but collapses and sticks together when none is present. There would be a massive amount of difficult in attempting to print/build said pipe under pressure.
In zero gravity you don't have to worry about pressurizing it, but you do exchange a new set of difficulties.
In zero gravity you don't have to worry about pressurizing it, but you do exchange a new set of difficulties.
> gravity is a bitch when making squishy things. They like to collapse under their own weight before they can harden.
It’s much cheaper to master fluid suspension.
It’s much cheaper to master fluid suspension.
I imagine a whole new wave of “innovation” for VC, it’s like Uber, but in space
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Oh, there will probably be several booms and busts. Stocks will go to the moon, and then back to earth, and then to the moon, etc. So it goes.
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I guess all we need now is an Epstein drive …
Only as a steping stone to Hoersch-Kessel ion engines. For FTL, I propose Kearny-Fuchida jump drives.
Honestly, I just wanted to nerd out.
Honestly, I just wanted to nerd out.
I understood every word of that. We can be friends.
Accepted!
Funny, how easy it can be to retain those totally unimportant facts, isn't it? I credit my English to a huge extend to stuff like that, after almost all those books came in English.
Funny, how easy it can be to retain those totally unimportant facts, isn't it? I credit my English to a huge extend to stuff like that, after almost all those books came in English.
I might remember more made up history of settings like BattleTech and Star Wars than I do actual real world history. I think I retain facts better the closer in proximity they are to lasers.
wasn't there a quote in the soft cover Mechwarrior RPG saying something along the lines of "whatever happened to the Universe while Einstein wasn't looking?"
I'd have to take a look at my library to verify! I love the Kearny-Fuchida backstory so, they were basically ridiculed crack heads, until decades after their death people jumped to New Earth (?) on the THS Pathfinder (?).
I don't see that quote on the cover of either 1st or 2nd edition of MechWarrior unfortunately. It does sound like something that would have been on some BT book however.
sorry I did not mean "on" the cover. I meant in "the soft cover Mechwarrior RPG" book, in some one of the pages inside. :)
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ah, another Battletech aficionado on the site
I just hope there are plenty more!
Given the funding of the BattleTech: Mercenaries kickstarter, I think that's a fairly safe assumption. (It's also really impressive consider the age of the game... I wonder if my Ral Partha miniatures are still around somewhere).
Mine are, they get expensive on eBay so... The last Battletech game is propably one of thebgakes I played the most, according to Steam statistics!
i like the idea of factories in space - just doubt the possibility. for example, can you imagine constructing a modern chip fab in orbit? it's hard enough down here.
Depending on what you're doing, it can be easier. No need for a clean room for the chips or an ultra-hard vacuum chamber for your extreme-UV laser when you're already in the cleanest hardest vacuum around.
I read somewhere that some specialist types of fibre optic cables already make sense to make in orbit just for the microgravity, but I don't know if that was a proposal to try it or if they already do…
I read somewhere that some specialist types of fibre optic cables already make sense to make in orbit just for the microgravity, but I don't know if that was a proposal to try it or if they already do…
> I read somewhere that some specialist types of fibre optic cables already make sense to make in orbit just for the microgravity, but I don't know if that was a proposal to try it or if they already do…
They are testing various prototypes on the ISS since 2019. Apparently the fibre quality is great and better than what we can make on earth [1], and the current prototypes are about automating the process.
I suspect that once access to space (and space stations) becomes cheap enough we will identify a lot of manufacturing processes where gravity is detrimental, and where the end product is valuable enough that shipping to and from space makes sense.
1: https://www.nasa.gov/directorates/spacetech/flightopportunit...
They are testing various prototypes on the ISS since 2019. Apparently the fibre quality is great and better than what we can make on earth [1], and the current prototypes are about automating the process.
I suspect that once access to space (and space stations) becomes cheap enough we will identify a lot of manufacturing processes where gravity is detrimental, and where the end product is valuable enough that shipping to and from space makes sense.
1: https://www.nasa.gov/directorates/spacetech/flightopportunit...
Still need clean room for humans that needed to operate it. If have completely automated it, then don’t need clean room on Earth. The vacuum chamber is cheaper than the laser. Both reasons are saving millions at the expense of billions.
Fabs are probably the worst factories to put in space because of how much human adjustment they require. Also, the equipment is expensive and delicate, and redesigning it to work in space would be enormously expensive. It would be ruinous to lose one. They require tons of chemicals to work, that have to come from Earth, and produce a lot of nasty waste, which still have to dispose of in space.
Fabs are probably the worst factories to put in space because of how much human adjustment they require. Also, the equipment is expensive and delicate, and redesigning it to work in space would be enormously expensive. It would be ruinous to lose one. They require tons of chemicals to work, that have to come from Earth, and produce a lot of nasty waste, which still have to dispose of in space.
Use robots instead of humans maybe.
All the equipment would need to be radiation-hardened, though, and radiation-hardening is pretty expensive, although maybe easier in low-Earth orbit.
https://en.wikipedia.org/wiki/Radiation_hardening
https://en.wikipedia.org/wiki/Radiation_hardening
Considering that most production in space (with even near future launch costs) would mainly only be worthwhile if the resources were also obtained from space, I don't think radiation shielding will be as much of an issue, since if you're doing ISRU, you can gather enough mass around the facility to handle shielding.
For chip fab in particular, since current processes require a lot of water, and water is very good as radiation shielding, such a facility in space would probably just store water in the walls.
For chip fab in particular, since current processes require a lot of water, and water is very good as radiation shielding, such a facility in space would probably just store water in the walls.
Well problem solved then ! Just find a lot of water in space not too far from earth, or a cheap way to create it in orbit.
Yeah, that's why I said that most things aren't worth producing in space without the ability to obtain resources from space. Kinda pointless if you just have to launch the water from Earth.
Could be the walls of the hangar to be hardened, not necessarily the whole equipment.
I'm not sure if it would be less expensive though
It's just heavier that way. The easiest way to rad harden things is to stick them in a big lead box. But that's not ideal for shipping things to space.
Alternatively I've seen some companies successfully rad-hardening from the software level. Effectively software that is tolerant to random bit flips.
Alternatively I've seen some companies successfully rad-hardening from the software level. Effectively software that is tolerant to random bit flips.
> easiest way to rad harden things is to stick them in a big lead box
Or work in a permanent shadow. Cosmic rays are easier to deal with than solar radiation.
Or work in a permanent shadow. Cosmic rays are easier to deal with than solar radiation.
This makes power generation a bit more challenging.
There are sun synchronous orbits (and the orbit at the dawn/dusk terminator is an interesting one - https://en.wikipedia.org/wiki/Sun-synchronous_orbit ), but there isn't an easy orbit around the Earth such that it is always in shadow... or rather, that's the Earth/Sun L2 point... which is where the JWST is. At that distance you lose the magnetic shielding of the Earth (and makes it even more expensive to get materials to and from it).
There are sun synchronous orbits (and the orbit at the dawn/dusk terminator is an interesting one - https://en.wikipedia.org/wiki/Sun-synchronous_orbit ), but there isn't an easy orbit around the Earth such that it is always in shadow... or rather, that's the Earth/Sun L2 point... which is where the JWST is. At that distance you lose the magnetic shielding of the Earth (and makes it even more expensive to get materials to and from it).
In (very) low earth orbit you can get by without radiation hardening. The ISS uses HP zbooks (and before that Thinkpads) and apparently they only really modify cooling and power, without any changes for radiation hardening.
Seems like they are reliable enough for their job and just need the occasional reboot. For more critical systems you could probably get by with three computers voting on the result, and if they disagree the outlier gets rebooted (a fairly standard setup in aviation and space)
Seems like they are reliable enough for their job and just need the occasional reboot. For more critical systems you could probably get by with three computers voting on the result, and if they disagree the outlier gets rebooted (a fairly standard setup in aviation and space)
The factory needs to be shielded. You can't really harden fine processes.
Right now, space manufacturing makes sense for exactly nothing. With enough research, it can in theory make sense for almost anything.
Right now, space manufacturing makes sense for exactly nothing. With enough research, it can in theory make sense for almost anything.
It turns out space is full of big floaty rocks that you could hollow out and put your factory inside.
And how many of these big floaty rocks are close enough go Earth?
Also, the equipment either needs to be made to work in vacuum or have to maintain atmosphere for it.
One thing I question is all of the materials that originate from petroleum, like polymers. I'm sure there's sufficient quantities of ore on other planets but anything made from polymers is going to only come from Earth. Are we just shipping the precursors to the moon and Mars or are we sending polymer products (Kevlar, Kapton, Tefzel, pretty much Dupont's entire high reliability catalog) to these places? Many synthetic polymers still rely on precursors that come from petroleum. It would require significant changes in how we produce many of the products we take for granted on Earth to be able to make them off-earth without just shipping massive tankers full of chemicals.
In theory you can synthesize petroleum, polymers, or any similar chemicals out of elemental hydrogen / carbon / oxygen / nitrogen / etc. It just takes enormous amounts of energy, some expensive catalysts, and an large heavy physical plant. So in practice we're not going to be able to do chemical manufacturing in space at scale for several centuries at least.
For hydrocarbons, we build chemical plants on Titan: https://www.esa.int/Science_Exploration/Space_Science/Cassin...
yes, really my first question is not "how do we make chip fabs?", but "how do we make insulated wire?"
I think it depends - the lack of Earths gravity could make it possibly much easier or much harder.
Definitely an interesting problem to look into. :)
Definitely an interesting problem to look into. :)
I think it would make a lot more sense to put stuff like this on the Moon. There's gravity, but only 1/6 as much, and you don't have to worry about environmental problems or generating vacuum. There's also water on the Moon.
Surprisingly, I know a great song about this!
Unexpected, I know. But https://www.youtube.com/watch?v=gFufOGZBwFM try that for size. Isn't it beautiful?
The well paced blips of the factory ships Slide past our orbit's brink Like a swarm of bees in the girder trees Come to our flowers to drink
And the earth is clean as a springtime dream No factory smokes appear For they've left the land to the gardener's hand And they all are circling here
Unexpected, I know. But https://www.youtube.com/watch?v=gFufOGZBwFM try that for size. Isn't it beautiful?
The well paced blips of the factory ships Slide past our orbit's brink Like a swarm of bees in the girder trees Come to our flowers to drink
And the earth is clean as a springtime dream No factory smokes appear For they've left the land to the gardener's hand And they all are circling here
This is Bezos vision (or the vision of the guy he paid to craft it for him) , anyway at least it gives some coherence to the space effort.
When people are talking about living on Mars or on the Moon, sane people automatically categorize them as crackpots, whereas moving heavy industry in orbit with the help of automation at least sets a path for some sort of ROI which is not the ridiculous "hop in the rocket bro we are going to Mars lmao"
When people are talking about living on Mars or on the Moon, sane people automatically categorize them as crackpots, whereas moving heavy industry in orbit with the help of automation at least sets a path for some sort of ROI which is not the ridiculous "hop in the rocket bro we are going to Mars lmao"
> Benefits: Earth: Materials and products that can not be manufactured or are much better
This is mostly guff from what I’ve seen, at least in the next hundred years.
This is mostly guff from what I’ve seen, at least in the next hundred years.
One of the things I've always been curious about - gravity is still very much exerting force on things in orbit, it's just that the object is moving along the perpendicular axis just as fast.
For someone smarter at physics than me - I get why this 'feels' like weightlessness/0G, but does it actually have that impact when it comes to physical manufacturing?
If it does, wouldn't terrestrial factories that have some sort of inertial roller coaster in them (akin to a vomit comet) be the cheaper/better answer?
EDIT: I think a lot of people are missing the point of my question here. Remember, objects in orbit are accelerating because they are changing direction.
This is different that being motionless in a far field with microgravity.
But in practice, does that acceleration matter for physical manufacturing?
For someone smarter at physics than me - I get why this 'feels' like weightlessness/0G, but does it actually have that impact when it comes to physical manufacturing?
If it does, wouldn't terrestrial factories that have some sort of inertial roller coaster in them (akin to a vomit comet) be the cheaper/better answer?
EDIT: I think a lot of people are missing the point of my question here. Remember, objects in orbit are accelerating because they are changing direction.
This is different that being motionless in a far field with microgravity.
But in practice, does that acceleration matter for physical manufacturing?
I think a lot of people are missing the point of my question here.
I believe it's you who are missing the point. Acceleration is irrelevant, it's how it's transmitted that matters. You feel gravity because the ground prevents you from falling exerting an opposite force, that is transmitted mechanically along your body.
There is no difference between free falling and no gravity except in monster gravitational fields like the one close to an event horizon where differential gravity (tide) could torn you apart. In any other situation you can safely assume that all the points in an object are pulled uniformly.
I believe it's you who are missing the point. Acceleration is irrelevant, it's how it's transmitted that matters. You feel gravity because the ground prevents you from falling exerting an opposite force, that is transmitted mechanically along your body.
There is no difference between free falling and no gravity except in monster gravitational fields like the one close to an event horizon where differential gravity (tide) could torn you apart. In any other situation you can safely assume that all the points in an object are pulled uniformly.
Direction is a fundamental aspect of acceleration, no?
I'm also not asking about what our brains are conditioned to feel. I am simply asking - is the constant acceleration of orbit fundamentally different than no acceleration, even if both would feel the same?
No-one has answered that in a compelling way.
Because to be clear - in one, no forces are being applied and in another, there are forces being applied (how else would you change directions?).
I'm also not asking about what our brains are conditioned to feel. I am simply asking - is the constant acceleration of orbit fundamentally different than no acceleration, even if both would feel the same?
No-one has answered that in a compelling way.
Because to be clear - in one, no forces are being applied and in another, there are forces being applied (how else would you change directions?).
I'm also not asking about what our brains are conditioned to feel.
Brain can't feel without senses input.
is the constant acceleration of orbit fundamentally different than no acceleration...?
No.
how else would you change directions?
You don't. You keep going straight, space is deformed by gravity.
But even if you look at it like in classical mechanics, the effect is applied uniformly to every particle of your body, so it makes no difference.
Ask yourself this: how do you feel gravity right now?
Brain can't feel without senses input.
is the constant acceleration of orbit fundamentally different than no acceleration...?
No.
how else would you change directions?
You don't. You keep going straight, space is deformed by gravity.
But even if you look at it like in classical mechanics, the effect is applied uniformly to every particle of your body, so it makes no difference.
Ask yourself this: how do you feel gravity right now?
>No.
Ok but why?
>You don't. You keep going straight, space is deformed by gravity.
Yeah, and if gravity weren't deforming the space, objects otherwise in orbit would move differently. That's just changing the mechanics (presumably in an attempt to appear more knowledgeable?) to avoid the question of why two wildly different scenarios (no forces vs. offsetting forces) are the exact same.
>But even if you look at it like in classical mechanics, the effect is applied uniformly to every particle of your body, so it makes no difference.
Again, my question is why in your model is the uniform application of a force the same as no application of a force?
>Ask yourself this: how do you feel gravity right now?
You don't have a sense for your own weight? I do and I don't know how to describe that feeling beyond that.
If I were in a true extremely low gravity situation (like deep space) I would feel differently.
Ok but why?
>You don't. You keep going straight, space is deformed by gravity.
Yeah, and if gravity weren't deforming the space, objects otherwise in orbit would move differently. That's just changing the mechanics (presumably in an attempt to appear more knowledgeable?) to avoid the question of why two wildly different scenarios (no forces vs. offsetting forces) are the exact same.
>But even if you look at it like in classical mechanics, the effect is applied uniformly to every particle of your body, so it makes no difference.
Again, my question is why in your model is the uniform application of a force the same as no application of a force?
>Ask yourself this: how do you feel gravity right now?
You don't have a sense for your own weight? I do and I don't know how to describe that feeling beyond that.
If I were in a true extremely low gravity situation (like deep space) I would feel differently.
presumably in an attempt to appear more knowledgeable?
O_o
Again, my question is why in your model is the uniform application of a force the same as no application of a force?
That's not my model, it's Einstein's.
O_o
Again, my question is why in your model is the uniform application of a force the same as no application of a force?
That's not my model, it's Einstein's.
> the object is moving along the perpendicular axis just as fast
Orbit is free fall. It’s equally correct to describe a falling object’s weightlessness as moving as fast as gravity.
> get why this 'feels' like weightlessness/0G, but does it actually have that impact when it comes to physical manufacturing
No, it’s the first postulate of Einstein’s theory of special relativity [1]. Free fall and the absence of gravity are as indistinguishable as acceleration and the its presence.
[1] https://en.m.wikipedia.org/wiki/Postulates_of_special_relati...
Orbit is free fall. It’s equally correct to describe a falling object’s weightlessness as moving as fast as gravity.
> get why this 'feels' like weightlessness/0G, but does it actually have that impact when it comes to physical manufacturing
No, it’s the first postulate of Einstein’s theory of special relativity [1]. Free fall and the absence of gravity are as indistinguishable as acceleration and the its presence.
[1] https://en.m.wikipedia.org/wiki/Postulates_of_special_relati...
Known as the equivalence principle: https://en.wikipedia.org/wiki/Equivalence_principle
In a curved orbit, that may be true at points, but for an extended object, tidal forces come into play:
https://en.wikipedia.org/wiki/Tidal_force
In a curved orbit, that may be true at points, but for an extended object, tidal forces come into play:
https://en.wikipedia.org/wiki/Tidal_force
The 'feeling' of weightlessness is pretty much an indication of 0 (micro) gravity. Gravity always exerts a force, the problem is on Earth we have ground exerting an equal and opposite force contrary to gravity. When you feel weightless whether in orbit or just falling off a cliff you're in free fall experiencing none of that upward opposition to gravitational force.
For example, it was very hard to replicate the moon's gravity when training pilots to land on the moon. How do you 'fake' a different gravity on Earth? It's pretty hard to do: https://www.youtube.com/watch?v=aw8kRZEvh_s
EDIT: to your question about centripetal force, either you experience acceleration or you don't. Since gravity is in equilibrium with centripetal force relative to movement around Earth you shouldn't get acceleration from this. However, you will get micro g's from rotation of the station itself, etc.
For example, it was very hard to replicate the moon's gravity when training pilots to land on the moon. How do you 'fake' a different gravity on Earth? It's pretty hard to do: https://www.youtube.com/watch?v=aw8kRZEvh_s
EDIT: to your question about centripetal force, either you experience acceleration or you don't. Since gravity is in equilibrium with centripetal force relative to movement around Earth you shouldn't get acceleration from this. However, you will get micro g's from rotation of the station itself, etc.
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>centripetal force relative to movement around Earth you shouldn't get acceleration from this.
If there is no acceleration, then how are objects changing direction?
If there is no acceleration, then how are objects changing direction?
The ISS will do a 360 degree rotation every 90 minutes to maintain its orientation relative to the surface of the Earth. This will result in bodies inside the ISS slowly rotating in the opposite direction of that rotation. However, this is unrelated to acceleration - these are constant angular velocities. The micro gravity I believe is the result of atmospheric drag, and the occasional boosting required to account for it.
Also I should add, it is confusing thinking about 0g, because obviously bodies in a gravity well are experiencing a gravitational force. Really we're talking about 0 acceleration, where g is the acceleration due to gravity. In orbit this g acceleration is cancelled out by centripetal acceleration to produce 0 acceleration, or free fall.
Also I should add, it is confusing thinking about 0g, because obviously bodies in a gravity well are experiencing a gravitational force. Really we're talking about 0 acceleration, where g is the acceleration due to gravity. In orbit this g acceleration is cancelled out by centripetal acceleration to produce 0 acceleration, or free fall.
>However, this is unrelated to acceleration - these are constant angular velocities.
If it were not for the force of gravity, an object in motion would move in the direction of its instantaneous velocity. It does not do that, it instead accelerates toward the center of the gravitational body.
>In orbit this g acceleration is cancelled out by centripetal acceleration to produce 0 acceleration, or free fall.
But again, they do not "cancel out," otherwise how is the instantaneous velocity constantly changing direction?
If it were not for the force of gravity, an object in motion would move in the direction of its instantaneous velocity. It does not do that, it instead accelerates toward the center of the gravitational body.
>In orbit this g acceleration is cancelled out by centripetal acceleration to produce 0 acceleration, or free fall.
But again, they do not "cancel out," otherwise how is the instantaneous velocity constantly changing direction?
You're bringing up the bizarre thing about gravity here. The only way we could be in 'free fall' undergoing 0 acceleration while still going in circles is if space itself were warped around an object.
Aren't bodies inside ISS rotating with it? Or are you implying that the rotation of ISS is not inertial but is constantly propelled by engines? If engines are driving it constantly, why is not constantly accelerating it's rotation?
True - thanks for the clarification. As long as the ISS is rotating at a constant rate anything oriented to it inside of it will not perceive it to be rotating. It's rotating relative to a stationary perspective on the surface of the Earth but by the time anything docks to it, everything in the system will be rotating at the same rate. Thanks for pointing this out!
Terrestrial factories for round lead shot do something like that. Just drop molten lead from the top of a tower and it will form a near perfect sphere as it falls weightless.
https://en.wikipedia.org/wiki/Shot_tower
https://en.wikipedia.org/wiki/Shot_tower
Assume the earth is a perfectly smooth sphere with a constant force of gravity and there is no air resistance:
Throw a ball parallel to the ground. Now throw it faster. It will land farther away than last time, right? Keep throwing it faster and faster and the ball will keep landing further and further away from you. Eventually, you throw it so fast that the ball flys through the air, all the way around the earth and lands back at your feet from behind you. You've just completed a single orbit around the earth. Keep throwing it faster and faster until the ball flies past you forever without touching the ground. This is a little hard to imagine because this speed is tremendous and something no one can really experience on earth.
The ball is constantly falling away from that direction you threw it originally due to gravity. Gravity is always acting on the ball and is always acting on any satellite in space as well. Gravity doesn't change that much for how high satellites fly. However the speed of the ball is just so such that it will never change from the height you originally threw it from.
Catch the ball out of the air and throw it just a little faster this time. The ball will still orbit but will pass over your head this time. The speed of the ball dictates the orbit altitude. Mass also factors in as well but not much for something so small. Grab it out of the air and keep throwing it faster and faster and eventually, the speed is able to overcome gravity and the ball leaves Earth's gravity entirely.
In Low Earth Orbit, there is just enough atmosphere to provide some minor air resistance that will actually slow down that ball you threw. As the ball slows, the orbit altitude decreases. As the altitude decreases, the atmosphere gets thicker and air resistance increases which makes the ball slow even more. It gets so slow that it can't maintain an orbit any more so it lands on the surface. If you attach a small rocket engine to the back of the ball, you can occasionally turn it on to maintain the exact speed you need for that orbit. If you use the rocket engine to make the ball go faster, you can raise the orbit. Rotate the ball 180deg and now you can use the rocket engine to slow the ball to lower the orbit.
Astronauts in space constantly have gravity on them but they are moving at such high speeds that gravity is not able to change their altitude. They are always "falling" just like the ball but never land. They float around inside their spacecraft because those too are falling constantly.
Throw a ball parallel to the ground. Now throw it faster. It will land farther away than last time, right? Keep throwing it faster and faster and the ball will keep landing further and further away from you. Eventually, you throw it so fast that the ball flys through the air, all the way around the earth and lands back at your feet from behind you. You've just completed a single orbit around the earth. Keep throwing it faster and faster until the ball flies past you forever without touching the ground. This is a little hard to imagine because this speed is tremendous and something no one can really experience on earth.
The ball is constantly falling away from that direction you threw it originally due to gravity. Gravity is always acting on the ball and is always acting on any satellite in space as well. Gravity doesn't change that much for how high satellites fly. However the speed of the ball is just so such that it will never change from the height you originally threw it from.
Catch the ball out of the air and throw it just a little faster this time. The ball will still orbit but will pass over your head this time. The speed of the ball dictates the orbit altitude. Mass also factors in as well but not much for something so small. Grab it out of the air and keep throwing it faster and faster and eventually, the speed is able to overcome gravity and the ball leaves Earth's gravity entirely.
In Low Earth Orbit, there is just enough atmosphere to provide some minor air resistance that will actually slow down that ball you threw. As the ball slows, the orbit altitude decreases. As the altitude decreases, the atmosphere gets thicker and air resistance increases which makes the ball slow even more. It gets so slow that it can't maintain an orbit any more so it lands on the surface. If you attach a small rocket engine to the back of the ball, you can occasionally turn it on to maintain the exact speed you need for that orbit. If you use the rocket engine to make the ball go faster, you can raise the orbit. Rotate the ball 180deg and now you can use the rocket engine to slow the ball to lower the orbit.
Astronauts in space constantly have gravity on them but they are moving at such high speeds that gravity is not able to change their altitude. They are always "falling" just like the ball but never land. They float around inside their spacecraft because those too are falling constantly.
IOW orbital mechanics is the art of falling whilst constantly missing the ground
Wouldn't delivery of products from factories in space to customers on Earth start to warm the atmosphere beyond our desired range directly - or at least as you begin to scale?
Slightly related: SMBC's guys have recently published a book on related topics, claiming it's got a lot of bibliographical research in it (disclaimer: haven't read it yet.) http://www.acityonmars.com/
It would be awesome to have space elevators all over the globe and create a LEO network for factories and logistics.
A man can dream.
A man can dream.
LEO is not accessible by space elevator at all. If you got off at ISS height you would just fall down.
Good for basejumping though. And no you wouldn't even need heatshield, just rugged EVA suite.
The elevator itself would need to extend past LEO into geostationary orbit, but you should be able to get off the elevator in LEO space.
As you're going up the space elevator, you would also be picking up horizontal velocity as you ascend. At ISS altitudes there would be enough atmospheric particles to slow you down once you got off, but it would take a while; probably on the order of years. Base jumping would not be a good idea.
As you're going up the space elevator, you would also be picking up horizontal velocity as you ascend. At ISS altitudes there would be enough atmospheric particles to slow you down once you got off, but it would take a while; probably on the order of years. Base jumping would not be a good idea.
I have always wondered if one could be strapped into a Falcon 9 fairing half and ride that down in an EVA suit. Coolest ride I can imagine.
"This is the missing piece to speed up development for the exciting Star Trek-like future."
Unbelievable misunderstanding of ST to think markets, or 'economic drivers' in their terms, would lead to anything like ST... The whole point of ST is that they are in communism or anarchism even. Nobody on the Enterprise was getting paid
Unbelievable misunderstanding of ST to think markets, or 'economic drivers' in their terms, would lead to anything like ST... The whole point of ST is that they are in communism or anarchism even. Nobody on the Enterprise was getting paid
Show me a prototype that works in Arizona desert, then I believe it.
How is that comparable? I apologize for this bit of sarcasm, but last I checked, Arizona has both air and gravity.
I think he's saying that if you can't do it in the desert then you shouldn't be talking about trying to do it in orbit. Work through the problems before you add in the launch costs and all of the other complications.
This is also what I say to people who propose a permanent Mars colony. They should be re-creating the Biosphere project right now and making it a success before the rocket is ready to go. There are a lot of problems that are seemingly still unaddressed with the whole project.
This is also what I say to people who propose a permanent Mars colony. They should be re-creating the Biosphere project right now and making it a success before the rocket is ready to go. There are a lot of problems that are seemingly still unaddressed with the whole project.
Fair enough. But with a biosphere, that makes sense. Mars has gravity and an atmosphere, so a biosphere on Earth is a smart project to resume.
I'm not saying we shouldn't test everything we can. We should, absolutely. But we also have to accept that the absence of gravity and operating in a vacuum are two major factors we could never adequately test on Earth.
I'm not saying we shouldn't test everything we can. We should, absolutely. But we also have to accept that the absence of gravity and operating in a vacuum are two major factors we could never adequately test on Earth.
Love the idea of factories in space. We need to separate the human from the supply chain interaction with raw and noxious materials and if we can do that in space we absolutely can terrestrially.
Totally expected this to be AI generated photos of factories floating in space before I clicked the link.
Similar vibe to cats on keyboards in space, you know?
https://www.knowyourmeme.com/memes/cat-on-a-keyboard-in-spac...
Similar vibe to cats on keyboards in space, you know?
https://www.knowyourmeme.com/memes/cat-on-a-keyboard-in-spac...
I was hoping it was a new game in the Factorio / Satisfactory genre :-)
Just in case you weren't aware, Dyson Sphere Program (https://store.steampowered.com/app/1366540/Dyson_Sphere_Prog...) is Factorio in space and I actually prefer it for reasons I can't exactly articulate. It's labeled as Early Access but my experience is that it's more stable an fun than some "production" games I've played
Oh my God please no. Zero-G Factorio would ruin my life, lose me my job and probably result in complete breakdown of human relationships.
Well there's Factorio Space Exploration mod which can easily take months to go through https://mods.factorio.com/mod/space-exploration
Sorry
Sorry
Pretty cool website and concept, but unfortunately mostly a delusional pipe dream until we develop fusion-based propulsion that makes orbital travel dirt cheap.
Here's a good summary of why it's mostly pipe dreams at the current tech level:
https://www.nasa.gov/mission_pages/station/expeditions/exped...
Here's a good summary of why it's mostly pipe dreams at the current tech level:
https://www.nasa.gov/mission_pages/station/expeditions/exped...
> until we develop fusion-based propulsion that makes orbital travel dirt cheap…here's a good summary
The tyranny of the rocket equation describes the exponential fuel cost of lifting propellant, with propellant, out of a gravity well.
One workaround is non-propellant launch [1], e.g. an orbital rail gun. (Fusion propulsion is still tyrannical because you’re carrying your propellant.) The other is in-situ resource utilisation, i.e. not lifting out of a gravity well.
[1] https://en.m.wikipedia.org/wiki/Non-rocket_spacelaunch
The tyranny of the rocket equation describes the exponential fuel cost of lifting propellant, with propellant, out of a gravity well.
One workaround is non-propellant launch [1], e.g. an orbital rail gun. (Fusion propulsion is still tyrannical because you’re carrying your propellant.) The other is in-situ resource utilisation, i.e. not lifting out of a gravity well.
[1] https://en.m.wikipedia.org/wiki/Non-rocket_spacelaunch
Ah, yes.
The response that just hand-waves a bunch of really hard problems or invents tech that doesn't exist.
I get it, HN has a lot of tech-optimists, but these responses are very tiring. Has there been legitimate significant progress on orbital guns or space elevators since 2012?
The response that just hand-waves a bunch of really hard problems or invents tech that doesn't exist.
I get it, HN has a lot of tech-optimists, but these responses are very tiring. Has there been legitimate significant progress on orbital guns or space elevators since 2012?
Wasn't the "super cheap fusion launch" predicated on discovering a non-Newtonian rocket engine? As long as you're suffering under the third law the idea of a super cheap launch is a pipe dream. This is also why concepts of reaching distant solar systems by maintaining 1G of thrust for the entire trip don't work. Plug the numbers for that into the rocket equation and even with absurd ISP values it requires more mass than is available in our solar system for a trip to even just Proxima Centauri.
The only maybe possible exception would be to pump so much energy into your reaction mass that it gains a significant amount of mass from relativity, but even that is engineering in the "it's probably easier to build a space elevator" realm.
The only maybe possible exception would be to pump so much energy into your reaction mass that it gains a significant amount of mass from relativity, but even that is engineering in the "it's probably easier to build a space elevator" realm.
> response that just hand-waves a bunch of really hard problems or invents tech that doesn't exist
The tyranny of the rocket equation is irrelevant to the problem of extraterrestrial manufacturing, at least in the short term. It’s all ISRU.
> Has there been legitimate significant progress on orbital guns or space elevators since 2012
Actually, yes. I’m sceptical of SpinLaunch. But they are making real progress on the technology, even if they aren’t the ones to complete the package to orbital delivery.
The tyranny of the rocket equation is irrelevant to the problem of extraterrestrial manufacturing, at least in the short term. It’s all ISRU.
> Has there been legitimate significant progress on orbital guns or space elevators since 2012
Actually, yes. I’m sceptical of SpinLaunch. But they are making real progress on the technology, even if they aren’t the ones to complete the package to orbital delivery.
Bezos does not expect to live long enough to see it happen, but he claims to want to put the building blocks in place.
https://en.wikipedia.org/wiki/Gerard_K._O%27Neill