system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: What are the benefits that zero-G environments provide to science or manufacturing?
gpt
At the moment its mainly for science. Not much commercial activity in space yet, outside of communication and observation satellites.

The main things that benefit from zero G are things to do with crystal formation, like alloys. Say you have a big pot of molten metal alloy. As it solidifies, some alloys form tiny crystals called dendrites. The way these dendrites overlap and intertwine determines the properties of the resulting alloy. In gravity dendrites are subjected to all kinds of convection currents, density fluctuations etc. As such, they grow in very irregular shapes and break before they grow too large. Therefore it is very hard to make an alloy that lives up to its theoretical properties. In space all these flows and currents are drastically reduced, or eliminated entirely. As such you get a much better alloy.

Same thing for many other things relating to crystal formation. Zero G allows for bigger, purer crystals.

If we look a few decades into the future, there are many things that could benefit from a space environment (provided launch costs go down, or we use materials readily available in space). Zero-G means you don't need to worry about support. This allows for much more versatile manufacturing methods. For example, right now silicium wafers used for semiconductor manufacturing are 300mm in diameter. Any bigger than that and the wafer flexes too much. In space the wafer won't flex due to gravity, as such you could conceivably have wafers tens of meters in diameter. Space is also a fantastic vacuum, which would really benefit semiconductor manufacture.

Another cool thing about space is that liquid droplets will quickly form perfect spheres thanks to surface tension. This is pretty useful for several industrial processes.

Zero G also allows you to mix normally unmixable gasses/liquids. Oil and water don't mix on earth, because the oil floats on top of water. In space they'll form a great emulsion for long periods of time. This allows for chemistry that's difficult or impossible on earth.

Space is also a great place for dangerous processes. If some industrial accident leaks thousands of tonnes of neurotoxics into the environment its a terrible disaster on earth. In space nobody would give a shit, outside of lost profit.

All in all, space manufacture would be pretty useful. But only if launch costs come waaaaay down, or we start exploiting asteroids and set up a nearly independent industry in space.