How are 3D printers likely to be used on the Moon or Mars?
They will print helmets and games.
They will print housing and labs.
They will print jetpacks and fuel.
They will print spacesuits and food.
They will be used to produce spare parts and tools for equipment and vehicles.
They could also be used to create structures and infrastructure, such as roads and shelters.
In addition, 3D printers could be used to create medical supplies and equipment, as well as personal items for astronauts living on these planets.