Mitsubishi Electric has developed an on-orbit additive-manufacturing technology that uses photosensitive resin and solar ultraviolet light for the 3D printing of satellite antennas in the vacuum of outer space. This novel technology enables structures to be fabricated in space using a 3D printer that extrudes a custom ultraviolet-curable resin that is stable in a vacuum environment through a low-power process that utilizes the sun’s ultraviolet to trigger crosslinking and polymerization. The technology specifically addresses the challenge of equipping small, inexpensive spacecraft buses with large structures, such as high-gain antenna reflectors. This eliminates the need for an antenna structure that can withstand vibrations and shocks during launch and contributes to the reduction in satellite weight and launch costs.