Scientists have experimented with manufacturing in microgravity for decades, especially aboard the ISS, which has mainly served as a test kitchen and is scheduled to be retired around 2030.
For drugmakers, crystal size, shape and arrangement can affect how easily medicines dissolve, how stable they are and how they can be given. In some cases that could let drugs now given by intravenous infusion be reformulated as more convenient injections.
The free-flying craft hitch rides into orbit on SpaceX rockets and carry miniature laboratories that process materials without astronauts. When experiments finish, a capsule separates, plunges through the atmosphere and parachutes to an uninhabited region.
Microgravity is a main reason to manufacture certain materials in space. On Earth, gravity makes particles in liquids settle and density differences create currents; both can interfere with crystal growth.
Inside one capsule, tiny crystals of a potential cancer drug were being grown in microgravity. The others were testing heat-protection materials and navigation systems for re-entry at hypersonic speeds.
Varda is among the furthest advanced in the approach, having already returned several capsules from orbit. The company is edging closer to operating a fleet of orbiting pharmaceutical factories.
Other materials, including semiconductors used in smartphones and electric vehicles, could also benefit. Microgravity and the absence of air could help produce purer crystals with fewer defects.
Several companies are developing commercial space stations to replace the ISS, while others design specialist laboratories and equipment for experiments aboard them.
ForgeStar-1 recently demonstrated some processes needed to manufacture semiconductor seed wafers, though it has yet to produce finished material and return it to Earth.
“Theoretically, it is this incredible material, but in practice you get a whole lot of defects in the crystals,” one account of the problem said. Reducing defects could yield much higher-performing material.