Space is indifferent to your suffering. It doesn't care that it'll freeze you to death unless you're wearing a fancy suit, or that even before freezing you'll suffocate in its vacuum. And it certainly doesn't care how difficult it is for humans to get stuff done in the void: practical things like screwing in bolts and drinking water and 3-D printing replacement parts.

But a company called Made in Space is indifferent to space's indifference. In a first, it's showed that it can 3-D print in a thermal vacuum chamber, which simulates the nastiness of space. It's a milestone in the outfit's ambitious Archinaut program, which hopes to launch a 3-D printer with robot arms into orbit. You know, to build things like satellites and telescopes and stuff.

This 3-D printer works like one you'd buy for yourself, extruding layer upon layer of polymer to build a structure. The difference being, this (deep breath...) Extended Structure Additive Manufacturing Machine is encased for thermal control, just like the components of a communications satellite would be to protect the electronics. "Our tactic has been, let's control the environment that's inside the printer, because we can't do anything about what's outside," says Eric Joyce, project manager of Archinaut.

The challenge is that Archinaut will have to print out tubes far larger than itself—which means the machine needs an aperture to spit out its creations. But that would expose its insides to the freezing vacuum as it's printing. So Joyce and the team selected components that are low outgassing, meaning they don't lose material in a vacuum. "There's nothing proprietary in our selection process," Joyce says. "Just good engineering." If all goes according to plan, one day Archinaut's robotic arms will use machine vision to grab printed parts as they leave the machine, then piece them together into satellites or dishes.