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…

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

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.

> 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.

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).

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.

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.

Also, the equipment either needs to be made to work in vacuum or have to maintain atmosphere for it.

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.

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)

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?

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.

Use robots instead of humans maybe.

> 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...

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. :)

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.

yes, really my first question is not "how do we make chip fabs?", but "how do we make insulated wire?"

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...

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.