Amid much fanfare, SpaceX started landing its Falcon 9 rockets in 2015, and it began reusing them less than two years later. The first stage of the Falcon 9 rocket, with nine engines and the bulk of the mass, accounts for about half of the cost of manufacturing a rocket, so this represents a considerable savings in time and money for SpaceX.

However, as with most other boosters, there are two other main components of the Falcon 9 rocket. There is the second stage, which boosts a payload into orbit, and, for most missions, a payload fairing that protects the satellite during its transit through the atmosphere. SpaceX briefly studied recovering the second stage of the Falcon 9 but concluded it was not feasible without major modifications that would have greatly reduced the rocket’s payload capacity.

But what about the payload fairing? These are built in two pieces through a laborious process of laying down composite materials, not dissimilar to papier-mâché. The manufacture of fairings is time-consuming, and it costs about $6 million to produce both halves.