The goal of 3-D printing is to take this capability to microgravity for use on the International Space Station. In space, whatever astronauts have available on orbit is what they have to use — but just like on Earth, parts break or get lost. When that happens, there’s a wait for replacement parts, or the need to have multiple spares that have to be launched. The ability to conduct 3-D printing in space could change all of that.